Using the AR-V7 biomarker to determine treatment in metastatic castrate resistant prostate cancer, a feasibility randomised control trial, conclusions from the VARIANT trial

Background

Prostate cancer is the most commonly diagnosed malignancy in the UK. Castrate resistant prostate cancer (CRPC) can be difficult to manage with response to next generation hormonal treatment variable. AR-V7 is a protein biomarker that can be used to predict response to treatment and potentially better inform management in these patients. Our aim was to establish the feasibility of conducting a definitive randomised controlled trial comparing the clinical utility of AR-V7 biomarker assay in personalising treatments for patients with metastatic CRPC within the United Kingdom (UK) National Health Service (NHS). Due to a number of issues the trial was not completed successfully, we aim to discuss and share lessons learned herein.

Methods

We conducted a randomised, open, feasibility trial, which aimed to recruit 70 adult men with metastatic CRPC within three secondary care NHS trusts in the UK to be run over an 18-month period. Participants were randomised to personalised treatment based on AR-V7 status (intervention) or standard care (control). The primary outcome was feasibility, which included: recruitment rate, retention and compliance. Additionally, a baseline prevalence of AR-V7 expression was to be estimated.

Results

Fourteen participants were screened and 12 randomised with six into each arm over a nine-month period. Reliability issues with the AR-V7 assay meant prevalence was not estimated. Due to limited recruitment the study did not complete to target.

Conclusions

Whilst the trial did not complete to target, we have ascertained that men with advanced cancer are willing to take part in trials utilising biomarker guided treatment. A number of issues were identified that serve as important learning points in future clinical trials.

Greater Transplant-Free Survival in Patients Receiving Obeticholic Acid for Primary Biliary Cholangitis in a Clinical Trial Setting Compared to Real-World External Controls

BACKGROUND & AIMS

The Primary Biliary Cholangitis (PBC) Obeticholic Acid (OCA) International Study of Efficacy (POISE) randomized, double-blind, placebo-controlled trial demonstrated that OCA reduced biomarkers associated with adverse clinical outcomes (ie, alkaline phosphatase, bilirubin, aspartate aminotransferase, and alanine aminotransferase) in patients with PBC. The objective of this study was to evaluate time to first occurrence of liver transplantation or death in patients with OCA in the POISE trial and open-label extension vs comparable non-OCA-treated external controls.

METHODS

Propensity scores were generated for external control patients meeting POISE eligibility criteria from 2 registry studies (Global PBC and UK-PBC) using an index date selected randomly between the first and last date (inclusive) on which eligibility criteria were met. Cox proportional hazards models weighted by inverse probability of treatment assessed time to death or liver transplantation. Additional analyses (Global PBC only) added hepatic decompensation to the composite end point and assessed efficacy in patients with or without cirrhosis.

RESULTS

During the 6-year follow-up, there were 5 deaths or liver transplantations in 209 subjects in the POISE cohort (2.4%), 135 of 1381 patients in the Global PBC control (10.0%), and 281 of 2135 patients in the UK-PBC control (13.2%). The hazard ratios (HRs) for the primary outcome were 0.29 (95% CI, 0.10-0.83) for POISE vs Global PBC and 0.30 (95% CI, 0.12-0.75) for POISE vs UK-PBC. In the Global PBC study, HR was 0.20 (95% CI, 0.03-1.22) for patients with cirrhosis and 0.31 (95% CI, 0.09-1.04) for those without cirrhosis; HR was 0.42 (95% CI, 0.21-0.85) including hepatic decompensation.

CONCLUSIONS

Patients treated with OCA in a trial setting had significantly greater transplant-free survival than comparable external control patients.

Photobiomodulation in the management of oral mucositis for adult head and neck cancer patients receiving irradiation: the LiTEFORM RCT

BACKGROUND

Oral mucositis is a debilitating and painful complication of head and neck cancer irradiation that is characterised by inflammation of the mucous membranes, erythema and ulceration. Oral mucositis affects 6000 head and neck cancer patients per year in England and Wales. Current treatments have not proven to be effective. International studies suggest that low-level laser therapy may be an effective treatment.

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of low-level laser therapy in the management of oral mucositis in head and neck cancer irradiation. To identify barriers to and facilitators of implementing low-level laser therapy in routine care.

DESIGN

Placebo-controlled, individually randomised, multicentre Phase III superiority trial, with an internal pilot and health economic and qualitative process evaluations. The participants, outcome assessors and therapists were blinded.

SETTING

Nine NHS head and neck cancer sites in England and Wales.

PARTICIPANTS

A total of 87 out of 380 participants were recruited who were aged ≥ 18 years and were undergoing head and neck cancer irradiation with ≥ 60 Gy.

INTERVENTION

Random allocation (1 : 1 ratio) to either low-level laser therapy or sham low-level laser therapy three times per week for the duration of irradiation. The diode laser had the following specifications: wavelength 660 nm, power output 75 mW, beam area 1.5 cm², irradiance 50 mW/cm², exposure time 60 seconds and fluence 3 J/cm². There were 20-30 spots per session. Sham low-level laser therapy was delivered in an identical manner.

MAIN OUTCOME MEASURE

The mean Oral Mucositis Weekly Questionnaire-Head and Neck Cancer score at 6 weeks following the start of irradiation. Higher scores indicate a worse outcome.

RESULTS

A total of 231 patients were screened and, of these, 87 were randomised (low-level laser therapy arm, n = 44; sham arm, n = 43). The mean age was 59.4 years (standard deviation 8.8 years) and 69 participants (79%) were male. The mean Oral Mucositis Weekly Questionnaire-Head and Neck Cancer score at 6 weeks was 33.2 (standard deviation 10) in the low-level laser therapy arm and 27.4 (standard deviation 13.8) in the sham arm.

LIMITATIONS

The trial lacked statistical power because it did not meet the recruitment target. Staff and patients willingly participated in the trial and worked hard to make the LiTEFORM trial succeed. However, the task of introducing, embedding and sustaining new low-level laser therapy services into a complex care pathway proved challenging. Sites could deliver low-level laser therapy to only a small number of patients at a time. The administration of low-level laser therapy was viewed as straightforward, but also time-consuming and sometimes uncomfortable for both patients and staff, particularly those staff who were not used to working in a patient's mouth.

CONCLUSIONS

This trial had a robust design but lacked power to be definitive. Low-level laser therapy is relatively inexpensive. In contrast with previous trials, some patients found low-level laser therapy sessions to be difficult. The duration of low-level laser therapy sessions is, therefore, an important consideration. Clinicians experienced in oral cavity work most readily adapt to delivering low-level laser therapy, although other allied health professionals can be trained. Blinding the clinicians delivering low-level laser therapy is feasible. There are important human resource, real estate and logistical considerations for those setting up low-level laser therapy services.

FUTURE WORK

Further well-designed randomised controlled trials investigating low-level laser therapy in head and neck cancer irradiation are needed, with similar powered recruitment targets but addressing the recruitment challenges and logistical findings from this research.

TRIAL REGISTRATION

This trial is registered as ISRCTN14224600.

FUNDING

This project was funded by the National Institute for Health and Care Research ( NIHR ) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 46. See the NIHR Journals Library website for further project information.

Clinical characteristics with inflammation profiling of long COVID and association with 1-year recovery following hospitalisation in the UK: a prospective observational study

BACKGROUND

No effective pharmacological or non-pharmacological interventions exist for patients with long COVID. We aimed to describe recovery 1 year after hospital discharge for COVID-19, identify factors associated with patient-perceived recovery, and identify potential therapeutic targets by describing the underlying inflammatory profiles of the previously described recovery clusters at 5 months after hospital discharge.

METHODS

The Post-hospitalisation COVID-19 study (PHOSP-COVID) is a prospective, longitudinal cohort study recruiting adults (aged ≥18 years) discharged from hospital with COVID-19 across the UK. Recovery was assessed using patient-reported outcome measures, physical performance, and organ function at 5 months and 1 year after hospital discharge, and stratified by both patient-perceived recovery and recovery cluster. Hierarchical logistic regression modelling was performed for patient-perceived recovery at 1 year. Cluster analysis was done using the clustering large applications k-medoids approach using clinical outcomes at 5 months. Inflammatory protein profiling was analysed from plasma at the 5-month visit. This study is registered on the ISRCTN Registry, ISRCTN10980107, and recruitment is ongoing.

FINDINGS

2320 participants discharged from hospital between March 7, 2020, and April 18, 2021, were assessed at 5 months after discharge and 807 (32·7%) participants completed both the 5-month and 1-year visits. 279 (35·6%) of these 807 patients were women and 505 (64·4%) were men, with a mean age of 58·7 (SD 12·5) years, and 224 (27·8%) had received invasive mechanical ventilation (WHO class 7-9). The proportion of patients reporting full recovery was unchanged between 5 months (501 [25·5%] of 1965) and 1 year (232 [28·9%] of 804). Factors associated with being less likely to report full recovery at 1 year were female sex (odds ratio 0·68 [95% CI 0·46-0·99]), obesity (0·50 [0·34-0·74]) and invasive mechanical ventilation (0·42 [0·23-0·76]). Cluster analysis (n=1636) corroborated the previously reported four clusters: very severe, severe, moderate with cognitive impairment, and mild, relating to the severity of physical health, mental health, and cognitive impairment at 5 months. We found increased inflammatory mediators of tissue damage and repair in both the very severe and the moderate with cognitive impairment clusters compared with the mild cluster, including IL-6 concentration, which was increased in both comparisons (n=626 participants). We found a substantial deficit in median EQ-5D-5L utility index from before COVID-19 (retrospective assessment; 0·88 [IQR 0·74-1·00]), at 5 months (0·74 [0·64-0·88]) to 1 year (0·75 [0·62-0·88]), with minimal improvements across all outcome measures at 1 year after discharge in the whole cohort and within each of the four clusters.

INTERPRETATION

The sequelae of a hospital admission with COVID-19 were substantial 1 year after discharge across a range of health domains, with the minority in our cohort feeling fully recovered. Patient-perceived health-related quality of life was reduced at 1 year compared with before hospital admission. Systematic inflammation and obesity are potential treatable traits that warrant further investigation in clinical trials.

FUNDING

UK Research and Innovation and National Institute for Health Research.

'Persistent throat symptoms' versus 'laryngopharyngeal reflux': a cross-sectional study refining the clinical condition

Objective

Many patients are assessed for chronic symptoms including: dysphonia, ‘globus’, throat clearing, postnasal secretions and cough; commonly grouped together and attributed to ‘laryngopharyngeal reflux’. This study aimed to explore a clinical trial’s baseline dataset for patterns of presenting symptoms, which might provide a more rational basis for treatment.

Design

Baseline data were analysed for participants entering the Trial Of Proton-Pump Inhibitors in Throat Symptoms: age, body mass index, Reflux Symptom Index, Comprehensive Reflux Symptom Score, Laryngopharyngeal Reflux-Health-related Quality of Life questionnaire and Reflux Finding Score (RFS-endoscopic examination). The relationships between the questionnaires and demographic factors were assessed. Exploratory factor analysis (EFA) was conducted on individual symptom items in the combined questionnaires. The EFA factors were applied to a Cluster Analysis of participants, to explore the presence of identifiable patient.

Results

Throat clearing and globus were the highest ranked scores in the 344 participants. Increasing age was inversely associated with symptom severity (p<0.01). There was no relationship between the RFS and any of the three questionnaires. EFA resulted in a seven-factor model with clinically meaningful labels: voice, cough, gastrointestinal symptoms, airway symptoms and dysphagia, throat clearing, lump in throat, and life events. Cluster analysis failed to demonstrate any clinically meaningful clusters of patients.

Conclusion

This study offers a framework for future research and demonstrates that individual symptoms cannot be used to group patients. The analysis supports the use of a broad ‘umbrella’ term such as persistent throat symptoms.

Trial registration number

ISRCTN38578686.

Multidrug-resistant Uro-associated Escherichia coli Populations and Recurrent Urinary Tract Infections in Patients Performing Clean Intermittent Self-catheterisation

Background

The AnTIC trial linked continuous low-dose antibiotic prophylaxis treatments to a lower incidence of symptomatic urinary tract infections (UTIs) among individuals performing clean intermittent self-catheterisation (CISC).

Objective

To explore potential mechanisms underlying the protective effects of low-dose antibiotic prophylaxis treatments, blood and urine samples and uro-associated Escherichia coli isolates from AnTIC participants were analysed.

Design, setting, and participants

Blood samples (n = 204) were analysed for TLR gene polymorphisms associated with UTI susceptibility and multiple urine samples (n = 558) were analysed for host urogenital responses. E.coli sequence data for 45 temporal isolates recovered from the urine samples of 16 trial participants in the prophylaxis (n = 9) and no-prophylaxis (n = 7) study arms, and characterised by multidrug resistance (MDR), were used to classify individual strains.

Outcome measurements and statistical analysis

TLR polymorphism data were analysed using Poisson regression. Concentrations of urine host defence markers were analysed using linear mixed-effects models, which accounted for repeated urine samples.

Results and limitations

Urine samples from CISC users, irrespective of antibiotic treatment regimens, were associated with robust urothelial innate responses. No links were identified between TLR genotype and CISC user susceptibility to recurrent UTIs. Microbiological study data were limited to the predominant MDR E. coli population; participants prescribed low-dose prophylactic antibiotics were predominantly colonised by a single uro-associated E. coli strain, while participants given acute antibiotic treatments were each colonised by more than one E. coli strain.

Conclusions

Antibiotic treatments did not impact urogenital responses to infection in CISC users. Host genetics in terms of TLR polymorphisms played no role in determining CISC user susceptibility to or protection from recurrent UTIs. Prophylactic antibiotic treatments associated with MDR E. coli were associated with colonisation by stable uro-associated E. coli genotypes.

Patient summary

Our findings show that the natural urogenital defences of clean intermittent self-catheterisation (CISC) users were not impacted by antibiotic treatments. For some CISC users, prophylaxis with low-dose antibiotics selected for a stable, predominantly, Esherichia coli rich uromicrobiota.

Reproducibility of 19 F-MR ventilation imaging in healthy volunteers

Purpose

To assess the reproducibility of percentage ventilated lung volume (%VV) measurements in healthy volunteers acquired by fluorine (¹⁹F)‐MRI of inhaled perfluoropropane, implemented at two research sites.

Methods

In this prospective, ethically approved study, 40 healthy participants were recruited (May 2018‐June 2019) to one of two research sites. Participants underwent a single MRI scan session on a 3T scanner, involving periodic inhalation of a 79% perfluoropropane/21% oxygen gas mixture. Each gas inhalation session lasted about 30 seconds, consisting of three deep breaths of gas followed by a breath‐hold. Four ¹⁹F‐MR ventilation images were acquired per participant, each separated by approximately 6 minutes. The value of %VV was determined by registering separately acquired ¹H images to ventilation images before semi‐automated image segmentation, performed independently by two observers. Reproducibility of %VV measurements was assessed by components of variance, intraclass correlation coefficients, coefficients of variation (CoV), and the Dice similarity coefficient.

Results

The MRI scans were well tolerated throughout, with no adverse events. There was a high degree of consistency in %VV measurements for each participant (CoV_observer1 = 0.43%; CoV_observer2 = 0.63%), with overall precision of %VV measurements determined to be within ± 1.7% (95% confidence interval). Interobserver agreement in %VV measurements revealed a high mean Dice similarity coefficient (SD) of 0.97 (0.02), with only minor discrepancies between observers.

Conclusion

We demonstrate good reproducibility of %VV measurements in a group of healthy participants using ¹⁹F‐MRI of inhaled perfluoropropane. Our methods have been successfully implemented across two different study sites, supporting the feasibility of performing larger multicenter clinical studies.

How applicable is the TNM 8 staging for human papillomavirus (HPV) related oropharyngeal squamous cell carcinoma (OPSCC) to a UK population of 106 patients? : A cohort comparison of the TNM 7 and TNM8 staging systems for HPV positive oropharyngeal cancer in a UK population

PURPOSE

TNM8 introduced a new staging system for HPV positive oropharyngeal squamous cell carcinoma (OPSCC). This study aimed to investigate whether the changes made in TNM8 offer the perceived benefit in prognostication when compared to TNM7 in a specific patient population in the North East of England.

METHODS

A retrospective cohort comparison study of all patients with HPV positive OPSCC (n = 106) through the Newcastle Head and Neck MDT between January 2012 to December 2014. Overall survival (OS) and Disease specific survival (DSS) data at 3 years was gathered for both TNM7 and TNM8. Log rank test was used to compare survival curves. Harrell's C-index adjusted for age and smoking status was used to assess prognostic ability of the two staging methods.

RESULTS

TNM8 downstages disease (TNM7 stage IV patients n = 74, TNM8 stage IV patients n = 2) but gives a more even distribution of patients across disease stages. Survival for TNM8 stage II and III is similar. In our small cohort, the log-rank test detected differences in OS between stages for both scoring methods (TNM7 p = 0.006, TNM8 p < 0.001) and similarly for DSS (TNM7 p = 0.001, TNM8 p < 0.001). Harrell's C-index was similar for both models for OS (TNM7 0.71, TNM8 0.71) and DSS (TNM7 0.74, TNM8 0.70).

CONCLUSION

TNM8 downstages disease and prognosticates well for stage I disease but does not differentiate between stage II and III disease when compared to TNM7. Further adaptation is required to address this to make TNM8 a more accurate prognostic tool.

Prostate cancer androgen receptor splice variant 7 biomarker study - a multicentre randomised feasibility trial of biomarker-guided personalised treatment in patients with advanced prostate cancer (the VARIANT trial) study protocol

INTRODUCTION

Prostate cancer is the most common male cancer with one in four developing non-curable metastatic disease. Initial treatment responses to hormonal therapies are transient and further management options lie between (1) further hormone therapy or (2) a non-hormonal approach involving additional chemotherapy or molecular radiotherapy (radium-223). There is no clear rationale for choosing between these mechanistically different treatment approaches. The biology of hormone resistance is driven through abnormal androgen receptor activity and we can assay this through a blood test measuring androgen receptor variant 7 (AR-V7) expression in circulating tumour cells. Despite increasing evidence supporting AR-V7's role as a prognostic marker, the clinical utility of such measures remains unknown in helping personalise treatment decisions.

METHODS AND DESIGN

The VARIANT feasibility trial is a pragmatic design, to be run over 18 months with participants randomised into the intervention arm receiving biomarker (AR-V7) guided clinical treatment and participants randomised into the control arm with conventional standard management (no biomarker guidance). AR-V7 positive participants (likely to be insensitive to further hormone treatment) will receive chemotherapy or in other cases radium-223 (where routinely available). Seventy male ≥18 years old participants with metastatic castrate resistant prostate cancer clinically indicated to proceed to further hormone therapy or chemotherapy, will be recruited from three National Health Service Trusts based in England, Scotland and Wales. The feasibility primary outcome is willingness of patients to be randomised and clinicians to recruit to a biomarker-based treatment strategy, with trial data informing the basis of a definitive and appropriately powered randomised control trial.

ETHICS AND DISSEMINATION

Formal ethics review was undertaken with a favourable opinion, through Wales NRES Committee 2 18/WA/0419. Findings to be disseminated through patient and professional organisations that have expressed their support, media outlets and peer-reviewed journal publication.

TRIAL REGISTRATION NUMBER

ISRCTN10246848; pre-results.

Pruritus Is Common and Undertreated in Patients With Primary Biliary Cholangitis in the United Kingdom

BACKGROUND AND AIMS

Little is known about the prevalence or treatment of pruritus associated with primary biliary cholangitis (PBC). We analyzed data from patients with PBC recruited from all clinical centers in the United Kingdom (UK) to characterize the prevalence, severity, progression, and treatment of pruritus.

METHODS

We performed cross-sectional and longitudinal studies of patients in the UK-PBC cohort to assess trajectories of pruritus. Data on pruritus frequency, severity, and therapy were collected via paper questionnaires completed by 2194 patients at their initial assessment in 2011 and then again in 2014 and 2017. Self-reported treatment data were validated against the prescription record of PBC cohort in the Clinical Practice Research Datalink, a primary care database. We defined persistent pruritus as itch that occurs frequently or all the time and severe pruritus as PBC-40 pruritus domain scores of 12 or more, throughout their disease course. Latent class mixed models were used to study pruritus trajectories and identify factors associated with high pruritus.

RESULTS

At initial assessment, 1613 (73.5%) patients had experienced pruritus at some point since their development of PBC-persistent pruritus was reported by 34.5% of the patients and severe pruritus by 11.7%. Only 37.4% of patients with persistent pruritus and 50% with severe pruritus reported ever receiving cholestyramine. Frequencies of rifampicin use were 11% in patients with persistent pruritus and 23% in patients with severe pruritus. Comparison of 2011 and 2014 surveys (comprising 1423 patients) showed consistent self-reported data on pruritus. Proportions of patients in the UK-PBC cohort treated with cholestyramine or naltrexone (37.4% and 4.4%) did not differ significantly from proportions treated in the Clinical Practice Research Datalink cohort (30.4% and 4.4%) (P = .07 for cholestyramine and P = .32 for naltrexone). Latent class mixed models (n = 1753) identified 3 different groups of pruritus. Multivariable analysis identified younger age at diagnosis and higher level of alkaline phosphatase at 12 months after diagnosis as factors significantly associated with persistent high pruritus.

CONCLUSIONS

In a large national cohort study of patients with PBC, we found a high prevalence of pruritus and inadequate guideline-recommended therapy. Patient-reported data used to determine pruritus prevalence and treatment are reliable. Younger age and levels of higher alkaline phosphatase were associated with persistent pruritus. We need to increase awareness and management of pruritus in PBC in the UK.

Continuous low-dose antibiotic prophylaxis to prevent urinary tract infection in adults who perform clean intermittent self-catheterisation: the AnTIC RCT

BACKGROUND

People carrying out clean intermittent self-catheterisation (CISC) to empty their bladder often suffer repeated urinary tract infections (UTIs). Continuous once-daily, low-dose antibiotic treatment (antibiotic prophylaxis) is commonly advised but knowledge of its effectiveness is lacking.

OBJECTIVE

To assess the benefit, harms and cost-effectiveness of antibiotic prophylaxis to prevent UTIs in people who perform CISC.

DESIGN

Parallel-group, open-label, patient-randomised 12-month trial of allocated intervention with 3-monthly follow-up. Outcome assessors were blind to allocation.

SETTING

UK NHS, with recruitment of patients from 51 sites.

PARTICIPANTS

Four hundred and four adults performing CISC and predicted to continue for ≥ 12 months who had suffered at least two UTIs in the previous year or had been hospitalised for a UTI in the previous year.

INTERVENTIONS

A central randomisation system using random block allocation set by an independent statistician allocated participants to the experimental group [once-daily oral antibiotic prophylaxis using either 50 mg of nitrofurantoin, 100 mg of trimethoprim (Kent Pharmaceuticals, Ashford, UK) or 250 mg of cefalexin (Sandoz Ltd, Holzkirchen, Germany); n = 203] or the control group of no prophylaxis (n = 201), both for 12 months.

MAIN OUTCOME MEASURES

The primary clinical outcome was relative frequency of symptomatic, antibiotic-treated UTI. Cost-effectiveness was assessed by cost per UTI avoided. The secondary measures were microbiologically proven UTI, antimicrobial resistance, health status and participants' attitudes to antibiotic use.

RESULTS

The frequency of symptomatic antibiotic-treated UTI was reduced by 48% using prophylaxis [incidence rate ratio (IRR) 0.52, 95% confidence interval (CI) 0.44 to 0.61; n = 361]. Reduction in microbiologically proven UTI was similar (IRR 0.49, 95% CI 0.39 to 0.60; n = 361). Absolute reduction in UTI episodes over 12 months was from a median (interquartile range) of 2 (1-4) in the no-prophylaxis group (n = 180) to 1 (0-2) in the prophylaxis group (n = 181). The results were unchanged by adjustment for days at risk of UTI and the presence of factors giving higher risk of UTI. Development of antimicrobial resistance was seen more frequently in pathogens isolated from urine and Escherichia coli from perianal swabs in participants allocated to antibiotic prophylaxis. The use of prophylaxis incurred an extra cost of £99 to prevent one UTI (not including costs related to increased antimicrobial resistance). The emotional and practical burden of CISC and UTI influenced well-being, but health status measured over 12 months was similar between groups and did not deteriorate significantly during UTI. Participants were generally unconcerned about using antibiotics, including the possible development of antimicrobial resistance.

LIMITATIONS

Lack of blinding may have led participants in each group to use different thresholds to trigger reporting and treatment-seeking for UTI.

CONCLUSIONS

The results of this large randomised trial, conducted in accordance with best practice, demonstrate clear benefit for antibiotic prophylaxis in terms of reducing the frequency of UTI for people carrying out CISC. Antibiotic prophylaxis use appears safe for individuals over 12 months, but the emergence of resistant urinary pathogens may prejudice longer-term management of recurrent UTI and is a public health concern. Future work includes longer-term studies of antimicrobial resistance and studies of non-antibiotic preventative strategies.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN67145101 and EudraCT 2013-002556-32.

FUNDING

This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in Health Technology Assessment Vol. 22, No. 24. See the NIHR Journals Library website for further project information.

Continuous low-dose antibiotic prophylaxis for adults with repeated urinary tract infections (AnTIC): a randomised, open-label trial

BACKGROUND

Repeated symptomatic urinary tract infections (UTIs) affect 25% of people who use clean intermittent self-catheterisation (CISC) to empty their bladder. We aimed to determine the benefits, harms, and cost-effectiveness of continuous low-dose antibiotic prophylaxis for prevention of recurrent UTIs in adult users of CISC.

METHODS

In this randomised, open-label, superiority trial, we enrolled participants from 51 UK National Health Service organisations. These participants were community-dwelling (as opposed to hospital inpatient) users of CISC with recurrent UTIs. We randomly allocated participants (1:1) to receive either antibiotic prophylaxis once daily (prophylaxis group) or no prophylaxis (control group) for 12 months by use of an internet-based system with permuted blocks of variable length. Trial and laboratory staff who assessed outcomes were masked to allocation but participants were aware of their treatment group. The primary outcome was the incidence of symptomatic, antibiotic-treated UTIs over 12 months. Participants who completed at least 6 months of follow-up were assumed to provide a reliable estimate of UTI incidence and were included in the analysis of the primary outcome. Change in antimicrobial resistance of urinary and faecal bacteria was monitored as a secondary outcome. The AnTIC trial is registered at ISRCTN, number 67145101; and EudraCT, number 2013-002556-32.

FINDINGS

Between Nov 25, 2013, and Jan 29, 2016, we screened 1743 adult users of CISC for eligibility, of whom 404 (23%) participants were enrolled between Nov 26, 2013, and Jan 31, 2016. Of these 404 participants, 203 (50%) were allocated to receive prophylaxis and 201 (50%) to receive no prophylaxis. 1339 participants were excluded before randomisation. The primary analysis included 181 (89%) adults allocated to the prophylaxis group and 180 (90%) adults in the no prophylaxis (control) group. 22 participants in the prophylaxis group and 21 participants in the control group were not included in the primary analysis because they were missing follow-up data before 6 months. The incidence of symptomatic antibiotic-treated UTIs over 12 months was 1·3 cases per person-year (95% CI 1·1-1·6) in the prophylaxis group and 2·6 (2·3-2·9) in the control group, giving an incidence rate ratio of 0·52 (0·44-0·61; p<0·0001), indicating a 48% reduction in UTI frequency after treatment with prophylaxis. Use of prophylaxis was well tolerated: we recorded 22 minor adverse events in the prophylaxis group related to antibiotic prophylaxis during the study, predominantly gastrointestinal disturbance (six participants), skin rash (six participants), and candidal infection (four participants). However, resistance against the antibiotics used for UTI treatment was more frequent in urinary isolates from the prophylaxis group than in those from the control group at 9-12 months of trial participation (nitrofurantoin 12 [24%] of 51 participants from the prophylaxis group vs six [9%] of 64 participants from the control group with at least one isolate; p=0·038), trimethoprim (34 [67%] of 51 vs 21 [33%] of 64; p=0·0003), and co-trimoxazole (26 [53%] of 49 vs 15 [24%] of 62; p=0·002).

INTERPRETATION

Continuous antibiotic prophylaxis is effective in reducing UTI frequency in CISC users with recurrent UTIs, and it is well tolerated in these individuals. However, increased resistance of urinary bacteria is a concern that requires surveillance if prophylaxis is started.

FUNDING

UK National Institute for Health Research.

Cavitation Threshold with Respect to Dp/Dt: Evaluation in 29 Mm Bileaflet, Pyrolitic Carbon Heart Valves

A total of 15 bileaflet mechanical heart valves were studied in a pulse duplicator at the Helmholtz Institute (Aachen, Germany) under conditions approximating first, a physiological pressure curve and subsequently, a sinusoidal pressure curve. In this study Edwards-Duromedics valves of the modified specification were compared with the earlier version of the Edwards-Duromedics valve as well as with St. Jude Medical valves. Each valve was tested at a series of nine (9) conditions. At each condition, without altering the valve installation or the systemic conditions, each valve was filmed by two separate video systems: the Helmholtz Institute strobe light system and a high speed video recording system. All data, as recorded by each system, was then independently analyzed by both of the two contributing groups and subsequently compared. In this manner, it was possible to objectively verify not only the consistency of the data obtained, but to also determine the relative reliability of the methods for cavitation threshold detection.

Prescribing in pregnancy for women with diabetes: use of potential teratogenic drugs and contraception

AIMS

To describe contraception use and the prescription of drugs that are either not recommended in pregnancy or are potentially teratogenic by diabetes type in women of child-bearing age.

METHODS

Retrospective, cross-sectional chart review undertaken in 22 general practices in Warwickshire, UK. Demographic, anthropometric, medical history, medication and contraception data were extracted from women aged 14 to 49 years with pre-existing diabetes. Independent sample t-test, Mann-Whitney test and χ(2) -test were used to test for univariable associations and multiple logistic regression was used to adjust for confounders.

RESULTS

Four hundred and seventy eligible women were identified; the majority had a diagnosis of Type 2 diabetes (67%). Thirty-six per cent and 64% of women with Type 1 and Type 2 diabetes, respectively, were prescribed drugs not recommended for use in pregnancy (P < 0.001). Less than half were using concomitant contraception (P < 0.001). No significant difference of contraception use was observed between women who were and were not taking drugs not recommended for use in pregnancy (40 vs. 41%, P = 0.4).

CONCLUSIONS

Use of drugs not recommended during pregnancy in women with diabetes of child-bearing age is common but is not associated with increased use of contraception. There is need to identify and overcome barriers to effective contraception use for this population group in order to facilitate optimal management of cardiovascular risk.

The experiences, needs, and Internet use of women recently diagnosed with HIV

Women constitute an increasing proportion of persons diagnosed with HIV in the United States. From September 2007 through June 2008, in-depth interviews were conducted with 20 women diagnosed with HIV in the previous 12 months to explore their experiences immediately following their diagnoses. Most women had at least a high school education (90%) and were African American (45%) or Hispanic (15%). Analysis of transcripts showed that: (a) many women were surprised by the diagnosis because they did not fit the profile of people at high risk for HIV, (b) obtaining social support immediately after an HIV diagnosis was a primary need, and (c) HIV had an impact on a woman's role in her family. We concluded that strategies are urgently needed to identify women at risk for HIV in a timely manner, and addressing the unique experiences and needs of women recently diagnosed with HIV is critical to their well-being.

Online resources for persons recently diagnosed with HIV/AIDS: an analysis of HIV-related webpages

The Internet is a major source of HIV-related information and resources for persons recently diagnosed with HIV/AIDS (PRDHA). This study examined the types of HIV-related websites that appear as a result of HIV-related keyword searches and the extent to which website information targets PRDHA. The first page of HIV-related webpages from 18 keyword searches was coded. Among 137 webpages meeting inclusion criteria, 63% represented HIV-informational websites, 31% targeted HIV-positive individuals, and over half contained or provided access to HIV prevention, treatment, and transmission information. Thirty-three percent of webpages contained or provided access to PRDHA-targeted information, with a greater percentage of those webpages having mobile, non-English, and "Ask the Expert" features compared with non-PRDHA targeted webpages. Implications for PRDHA include the following: (1) they should explore HIV-related websites to gain insight into the credibility of the information contained on those sites; (2) PRDHA must be aware that HIV-related websites have the potential to elicit dated, emotionally distressing, or irrelevant information; and (3) to obtain information that relates to their demographic and situational profile, they may wish to use specific key terms (e.g., "HIV women") rather than attempting to navigate webpages that arise from general search terms (e.g., "HIV"). Recommendations for future development of online resources for PRDHA include providing HIV-relevant information in a stepwise fashion, providing demographically targeted HIV information, and greater utilization of mobile technology.

Perceptions of HIV-related websites among persons recently diagnosed with HIV

Many HIV-positive persons use the Internet to address at least some of their needs for HIV-specific information and support. The aim of this multimethod study was to understand how a diverse sample of persons who were recently diagnosed with HIV (PRDH) used the Internet after an HIV diagnosis and their perceptions of online HIV-related information and resources. HIV-positive persons (N = 63) who had been diagnosed since the year 2000 were recruited primarily through HIV-related websites and HIV medical clinics. One third of participants (33%, n = 21) were gay or bisexual men, 25% (n = 16) were heterosexual men, 32% (n = 20) were heterosexual women, and 10% (n = 6) were transgender women (male to female). Semistructured interviews and brief postinterview surveys were used to collect qualitative and quantitative data. Qualitative findings suggested that the most appealing websites to PRDH included those that: (1) provided usable information on topics of immediate concern; (2) used accessible formats that were easy to navigate; (3) were perceived as trustworthy, and (4) provided access to diverse perspectives of persons living with HIV/AIDS. Topics that PRDH found most useful included various medical treatment-related issues, tools for coping with depression and fear, and learning how others cope with HIV. Incorporating the perspectives of HIV-positive persons into the design and content of HIV-related websites is important to enhance their appeal for this diverse and growing population.

Using the Internet to provide care for persons living with HIV

There are no published reports on ways in which caregivers use the Internet to support people living with HIV/AIDS (PLWHA). Five hundred caregivers were recruited in a 5-week period to complete an online survey of demographic characteristics, Internet use, online health-seeking self-efficacy, and ways they used the Internet to support PLWHA. Caregivers were on average 39 years old, white, heterosexual, highly educated, and Internet-savvy. Most provided informal care only (e.g., as a friend; 78%), with the remainder divided among those who provided care exclusively as part of their job (11%) or in both informally and professionally (11%). Most (72%) respondents visited a general medical website for HIV information, and 44% shared information from the Internet with PLWHA. Compared to informal caregivers, caregivers whose roles were both informal and professional had greater odds of recently sharing information from the Internet with PLWHA (odds ratio [OR] = 2.03) and ever printing off information from a website to give to PLWHA (odds ratio [OR] = 3.87). Professional caregivers had higher odds of ever printing off information from a website to give to PLWHA (OR = 1.87), but lower odds of sending an e-mail with a website link (OR = 0.32) than informal caregivers. These findings suggest that websites providing HIV-related resources should consider the various ways in which caregivers use their content, and how utilization differs by role. More research is needed to understand how people providing care for PLWHA share information and support each other and the impact that doing so has on caregiver burden and treatment outcomes for PLWHA.

Ethnicity, social disadvantage and psychotic-like experiences in a healthy population based sample

OBJECTIVE

We sought to investigate the prevalence and social correlates of psychotic-like experiences in a general population sample of Black and White British subjects.

METHOD

Data were collected from randomly selected community control subjects, recruited as part of the AESOP study, a three-centre population based study of first-episode psychosis.

RESULTS

The proportion of subjects reporting one or more psychotic-like experience was 19% (n = 72/372). These were more common in Black Caribbean (OR 2.08) and Black African subjects (OR 4.59), compared with White British. In addition, a number of indicators of childhood and adult disadvantage were associated with psychotic-like experiences. When these variables were simultaneously entered into a regression model, Black African ethnicity, concentrated adult disadvantage, and separation from parents retained a significant effect.

CONCLUSION

The higher prevalence of psychotic-like experiences in the Black Caribbean, but not Black African, group was explained by high levels of social disadvantage over the life course.

Self-reported childhood trauma correlates with schizotypal measures in schizophrenia but not bipolar pedigrees

BACKGROUND

Strong evidence supports the association between childhood trauma and psychotic disorders. In two different high-risk populations, we looked for a correlation between the magnitude of schizotypal dimensions and the importance of self-reported childhood trauma.

METHOD

A sample of 138 unaffected first-degree relatives was recruited (67 relatives of schizophrenic probands and 71 relatives of bipolar probands). The relationship between schizotypal dimensions and childhood trauma scores was analyzed by partial correlations.

RESULTS

A positive correlation was found between childhood trauma scores and total schizotypal scores in first-degree relatives of schizophrenic subjects but not in first-degree relatives of bipolar probands. This correlation was primarily due to a strong association with the positive dimension of schizotypy.

CONCLUSIONS

The significant correlation between childhood trauma and schizotypal dimensions in subjects at high genetic risk for schizophrenia suggests that susceptibility genes for schizophrenia may interact with childhood trauma to induce the emergence of schizotypal dimensions, mainly positive psychotic features.

Cognitive-behavioural interventions for preventing youth gang involvement for children and young people (7-16)

BACKGROUND

Many studies document a robust and consistent relationship between gang membership and elevated delinquency, with gang members disproportionately involved in crime compared to non-gang peers. Research also indicates that both delinquent youth and youth who join gangs often show a wide range of deficient or distorted social-cognitive processes compared to non-delinquent peers. Cognitive-behavioural interventions are designed to address cognitive deficits in order to reduce maladaptive or dysfunctional behaviour, and studies have documented their positive impact on a number of behavioural and psychological disorders among children and youth.

OBJECTIVES

To determine the effectiveness of cognitive-behavioural interventions for preventing youth gang involvement for children and young people (ages 7-16).

SEARCH STRATEGY

Electronic searches of ASSIA, CINAHL, CJA, Cochrane Library, Dissertations Abstracts A, EMBASE, ERIC, IBSS, LILACs, LexisNexis Butterworths, MEDLINE, NCJR Service Abstracts Database, PsycINFO, and Sociological Abstracts, to April 2007. Reviewers contacted relevant organisations, individuals, and list-servs and searched pertinent websites and reference lists.

SELECTION CRITERIA

All randomised controlled trials or quasi-randomised controlled trials of interventions with a cognitive-behavioural intervention as the majority component, delivered to youth and children aged 7-16 not involved in a gang.

DATA COLLECTION AND ANALYSIS

Searching yielded 2,284 unduplicated citations, 2,271 of which were excluded as irrelevant based on title and abstract. One was excluded following personal communication with investigators. One citation, of a large randomised prevention trial, awaits assessment; personal communication with study authors yielded unpublished reports addressing gang outcomes, but insufficient detail precluded determining inclusion status. Seven remaining reports were excluded as irrelevant because they were narrative reviews or descriptions of programs without evaluations, did not address a gang prevention programme, or did not address a gang prevention program that included a cognitive-behavioural intervention. The remaining four full-text reports excluded because of study design, leading to 0 included studies.

MAIN RESULTS

No randomised controlled trials or quasi-randomised controlled trials were identified.

AUTHORS' CONCLUSIONS

No evidence from randomised controlled trials or quasi-randomised controlled trials exists regarding the effectiveness of cognitive-behavioural interventions for gang prevention. Four evaluations of Gang Resistance Education and Training (GREAT) have been conducted, two of which were part of a US national evaluation, but all were excluded based on study design. Reviewers conclude there is an urgent need for rigorous primary evaluations of cognitive-behavioural interventions for gang prevention to develop this research field and guide future gang prevention programmes and policies.

Potential of modern technologies for improvement of in vivo calibration

In the frame of IDEA project, a research programme has been carried out to study the potential of the reconstruction of numerical anthropomorphic phantoms based on personal physiological data obtained by computed tomography (CT) and Magnetic Resonance Imaging (MRI) for calibration in in vivo monitoring. As a result, new procedures have been developed taking advantage of recent progress in image processing codes that allow, after scanning and rapidly reconstructing a realistic voxel phantom, to convert the whole measurement geometry into computer file to be used on line for MCNP (Monte Carlo N-Particule code) calculations. The present paper overviews the major abilities of the OEDIPE software studies made in the frame of the IDEA project, on the examples of calibration for lung monitoring as well as whole body counting of a real patient.

Alterations in alcohol consumption, withdrawal seizures, and monoamine transmission in rats treated with phentermine and 5-hydroxy-L-tryptophan

We have previously shown that coadministration of the dopamine (DA) agonist phentermine plus the serotonergic agonist fenfluramine suppresses alcohol intake and withdrawal seizures in rats. In the present study, phentermine and the serotonin (5-HT) precursor, 5-hydroxy-L-tryptophan (5-HTP), were administered alone, or in combination, to rats fed on a 6% alcohol-containing diet or an isocaloric control diet. Following a 9-h withdrawal period from the alcohol-containing diet, phentermine enhanced the effects of 5-HTP on both reduction of alcohol withdrawal seizures as well as changes in striatal serotonin. Food intake was monitored for 24 h after drug treatment, and neurochemical measures were examined at various time points. Phentermine alone reduced food intake in all diet conditions, but this anorectic effect was followed by hyperphagia in control rats. Phentermine plus 5-HTP reduced the consumption of the alcohol-containing diet, while its effects on consumption of control diets were mixed. In vivo microdialysis in rat nucleus accumbens revealed that phentermine increased extracellular DA, whereas 5-HTP caused marked elevations in extracellular 5-HT. Coadministration of phentermine and 5-HTP evoked simultaneous elevations in extracellular DA and 5-HT that mirrored the effects of each drug alone. Collectively, these findings show that coadministered phentermine plus 5-HTP is effective in reducing alcohol intake and suppressing alcohol withdrawal seizures. These therapeutic actions may be related to elevations in synaptic DA and 5-HT in critical brain regions.

Role of monoamine oxidase inhibition and monoamine depletion in fenfluramine-induced neurotoxicity and serotonin release

The role of both monoamine synthesis and monoamine oxidase inhibition in mediating the fenfluramine-induced damage to serotonin neurones was examined; as pretreatment agents, both alpha-methyl-para-tyrosine (AMPT) and parachlorophenylalanine (PCPA) were used to deplete dopamine and serotonin, respectively, while clorgyline and deprenyl were used to inhibit monoamine oxidase types A and B. While both AMPT and deprenyl did not alter fenfluramine induced serotonin or 5-hydroxyindoleacetic acid (5-HIAA) depletion in any area, PCPA did partially reduce the serotonin depletion in the hippocampus and hypothalamus. Although pretreatment with clorgyline did not significantly alter fenfluramine-induced serotonin depletion, it did produce a 65% mortality rate in animals treated with both drugs. Both PCPA and clorgyline significantly increased the depletion of striatal 5-HIAA concentration consequent to fenfluramine; however, these drugs also produced a long-term depletion of striatal 5-HIAA when administered alone, therefore, the changes seen after the coadministration with fenfluramine may be viewed as additive. Finally, acute PCPA pretreatment attenuated the rapid rise in 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (homovanillic acid) induced by fenfluramine, and acute clorgyline reversed the drop in serotonin and rise in 5-HIAA induced by fenfluramine. These results indicate that the rapid increase in dopamine activity induced by fenfluramine is partially dependent on serotonin concentration and release and that the mechanism of fenfluramine-induced toxicity is unlike that of the other substituted amphetamines.

Monoaminergic changes associated with audiogenic seizures in ethanol-dependent rats

1. A previous report demonstrated the efficacy of combining dopaminergic and serotonergic agonists in suppressing audiogenic seizures induced in ethanol-dependent rats undergoing withdrawal. Moreover, an increase in dopamine and a reduction in serotonin levels in the striatum were associated with such seizures. 2. The present study was designed to examine neurochemical changes in the striatum associated with repeated episodes of ethanol withdrawal seizures in untreated ethanol-dependent rats as well as in those treated with amphetamine and fenfluramine in combination. 3. Ethanol-dependent rats undergoing audiogenic seizures exhibited an increase in striatal dopamine and a reduction in striatal serotonin as compared to control and ethanol-dependent rats not undergoing seizures. Amphetamine and fenfluramine in combination effectively suppressed the audiogenic seizures by reversing the neurochemical changes in the striatum in ethanol-dependent rats. However, increased dopamine but decreased serotonin levels in the striatum were observed in rats undergoing one episode of ethanol withdrawal, but not in those experiencing multiple episodes of ethanol withdrawal. 4. Thus, alterations in striatal dopamine and serotonin levels were, at best, necessary but not sufficient to predispose audiogenic seizure susceptibility in ethanol-dependent rats.

Modulation of the SNARE core complex by dopamine

Communication between nerve cells in the brain occurs primarily through specialized junctions called synapses. Recently, many details of synaptic transmission have emerged. The identities of specific proteins important for synaptic vesicle release have now been established. We have investigated three synaptic proteins, VAMP (vesicle associated membrane protein; also called synaptobrevin), syntaxin, and SNAP25 (synaptosomal associated protein of 25kDa) as possible targets in the dopamine-mediated modulation of synaptic function in rat striatal slices. These three proteins form a SNARE (soluble N-ethylmalemide-sensitive factor attachment protein receptors) core complex that is known to be essential for synaptic transmission. Although it is envisioned that the SNAREs undergo dynamic and cyclic interactions to elicit synaptic vesicle release, their precise functions in neurotransmission remains unknown. We have examined SNARE complexes in intact rat striatal slices. Cellular proteins were solubilized, separated electrophoretically by SDS-PAGE, and then identified immunologically. Application of dopamine to striatal slices results in SNAREs favoring the SNARE core complex, a complex which forms spontaneously in the absence of crosslinking agents, rather than the monomer form. In addition, rapid crosslinking of dopamine-treated striatal slices demonstrates that the SNARE complex is increased 4 fold in dopamine treated striatal slices compared with control slices. Haloperidol blocked the dopamine-induced change in the core complex. These results suggest that changes in the activities of SNAREs may be involved in the underlying cellular mechanisms(s) of dopamine-regulated synaptic plasticity of the striatum.

First, build the foundations: practical considerations in general practitioner-mental health service liaison

The co-working relationship between general practitioners and local mental health services lies at the heart of the success of recent changes in mental health care. These changes have seen large-scale deinstitutionalisation, a shift to primary and community care, and a government policy of prevention and partnerships. This article outlines a liaison project developed jointly by the South-East New South Wales Division of General Practice and the Southern Area Mental Health Service to address these issues. We describe the development of a protocol of basic standards which were practical, pragmatic and possible and, when fully established, would be the foundation of effective, efficient and efficacious shared care in mental health.

A new remote-controlled endoscope positioning system for endoscopic solo surgery. The FIPS endoarm

In the field of endoscopic solo surgery, the assistance received by the surgeon from ergonomical positioning devices is extremely important. They aid in both the retracting of instruments and the positioning of the endoscope. However, passive systems derived from open surgery have not proved satisfactory. Therefore, we set out to develop a remote-controlled arm capable of moving a rigid endoscope with about four degrees of freedom, while maintaining an invariant point of constraint motion coincident with the trocar puncture site through the abdominal wall. The system is driven by means of speaker-independent voice control or a finger-ring joystick clipped onto the instrument shaft close to the handle. When the joystick is used, the motion of the endoscope is controlled by the fingertip of the operating surgeon, which is inserted into the small ring of the controller in such a way as to make the motion of the fingertip correspond directly to the motion of the tip of the endoscope. A study was performed to compare the two different interfaces available for the system. With both interfaces, the guiding system allows for transparent and intuitive operation. Its set-up is easy; it is safe and reliable to use during the intervention; and it is faster than human assistance. With its improved ergonomy, this new generation of remote-controlled endoscope positioning system represents a further step toward the diffusion of solo surgery techniques in minimally invasive therapy. In our opinion, this prototype creates a valid compromise between human and robotic control of rigid endoscopes.

Effects of phentermine and fenfluramine on alcohol consumption and alcohol withdrawal seizures in rats

The drug combination of phentermine plus fenfluramine has been used clinically in both the treatment of obesity and alcoholism. The aim of the current study was to assess the interaction of the two drugs on consumption of both an alcohol-containing and a nonalcoholic diet. Furthermore, the efficacy of the drug combination on suppression of withdrawal seizures was determined. Animals were either maintained on a 6% alcohol-containing diet, free-fed an isocaloric control, or pair-fed the control diet. It was observed that, with regard to body weight growth curves, alcohol provides about 2.5 kcal/g. Both phentermine and fenfluramine caused a decrease in consumption 1 h after administration; however, during the next 23 h, 4 mg/kg phentermine significantly increased consumption of all diets. At doses of 1 and 2 mg/kg, fenfluramine selectively reduced consumption of the alcohol-containing diet as compared to the isocaloric diets. Lower doses of fenfluramine blocked the increases in consumption induced by phentermine. Furthermore, in animals fed the nonalcoholic diet, the drug combination of 2 mg/kg fenfluramine plus 8 mg/kg phentermine produced a 63-82% reduction in consumption, an effect not seen when either drug was administered alone. This greater than additive effect was also seen in the earlier time periods in animals pair-fed the control diet. Neurochemical analysis from these animals revealed that the alcohol-dependent animals displayed a significant reduction of DOPAC and 5-HIAA levels in the striatum, frontal cortex, and hypothalamus after a 9-h withdrawal period, further implicating the serotonergic and dopaminergic systems in mediation of withdrawal symptoms and alcohol craving. Finally, 8 mg/kg phentermine plus 8 mg/kg fenfluramine completely abolished alcohol withdrawal seizures, compared to a 78% rate in saline treated rats. In conclusion, the coadministration of phentermine plus fenfluramine produced a moderate reduction of alcohol consumption and was completely effective at reducing alcohol withdrawal seizures.

A genetically engineered spleen necrosis virus-derived retroviral vector that displays the HIV type 1 glycoprotein 120 envelope peptide

We reported that SNV-derived retroviral vectors, which display single-chain antibodies on the viral surface, enable cell type-specific gene delivery into various human cells. In particular, the SNV cell type-specific gene delivery vector system appears to be well suited to transduce genes into cells of the human hematopoietic system (Jiang et al., J. Virol. 72:10148-10156, 1998). Here, we report the construction of SNV vector particles that display the complete gp120 surface unit of the envelope protein of human immunodeficiency virus type 1 (HIV-1) on the viral surface. The complete gp120-coding region of a T cell-tropic HIV-1 strain (LAI/BRU) was fused to a short peptide spacer coding region [(Gly4Ser)3] linking it to the SNV TM-coding region. The corresponding protein was expressed as a single 145-kDa peptide as expected. This peptide was nontoxic and could be stably expressed in dog D17 SNV-derived packaging cells. Particles harvested from stable packaging lines infected CD4+ human hematopoietic cells with titers exceeding 10(5) CFU/ml supernatant tissue culture medium. Titers in other, CD4- cell lines expressing various coreceptors of HIV-1 were 100-fold lower than titers obtained in CD4+ cells. Specificity of infection was demonstrated by antibody inhibition assays or by preincubating cells with SDF-1alpha, the ligand, which binds to the CXCR4 coreceptor, to which this gp120 binds. Our data indicate that binding of the HIV-1 gp120 to either CD4 or CXCR4 is sufficient to enable infection of human cells with SNV vector particles. We constructed retroviral vector particles that display chimeric HIV-1-SU-SNV-TM proteins plus wild-type SNV envelope on the viral surface. Such particles allowed efficient infection of CD4-positive human T lymphocytes, and, at a lower efficiency, also cells expressing CXCR4 without CD4. These data coincide with our earlier hypothesis that the chimeric envelope is required only to bind the vector particle to a cell surface receptor of the target cell, while membrane fusion is mediated by wild-type Env, which alone is not sufficient to enable infection of human cells.

Dose-dependent up-regulation of rat pulmonary, renal, and hepatic cytochrome P-450 (CYP) 1A expression by nicotine feeding

In a previous study in which a single 2.5 mg/kg (15.4 micromol/kg) s. c. dose of nicotine effected a transient, lung-specific induction of cytochrome P-450 (CYP) 1A1 in the rat, a dose-response study and assessment of the lung specificity of the induction was limited by toxicity of the acute parenteral nicotine exposure. In the present study, we examined the dose-CYP1A1/2 induction response relationship and the tissue specificity of the induction by orally administered nicotine, which lacks the toxicity of the parenterally administered drug. Nicotine, administered in a nutritionally balanced liquid diet, at a level of 20 (low), 60 (medium), or 200 (high) mg/kg of diet, induced CYP1A1 in the lung and kidney in a dose-dependent manner and in the liver at the high nicotine dose only, whereas CYP1A2 was induced in the liver dose-dependently and in the kidney at the high nicotine dose only. The high nicotine dose up-regulated mRNA level in the three tissues examined, but with the lung being the most responsive to the up-regulation. Induction of the CYP1A1-preferential activity ethoxyresorufin O-deethylase by the low, medium, and high nicotine diets was 1.9-, 4.9-, and 21.6-fold, respectively, in the lung, 1.4-, 1.7-, and 15.9-fold, respectively, in the kidney, and 1.7-, 2.9-, and 5.1-fold, respectively, in the liver. Similarly, albeit to lower extents, the dietary alkaloid induced the CYP1A2-preferential activity methoxyresorufin O-demethylase in all three tissues dose-dependently. Plasma nicotine concentration correlated neither with the dietary nor intake dose of the alkaloid nor with tissue levels of CYP1A, especially with the high-dose diet. Plasma nicotine levels at which CYP1A induction was maximal were comparable to those reported in smokers, suggesting that nicotine may induce CYP1A1 in humans.

Efficacy of providing nicotine in a liquid diet to rats

To determine if rats would consume nicotine at psychoactive levels, a nutritionally balanced diet with 0, 20, 60, or 200 mg of nicotine tartrate per kg of diet was provided. Diet consumption and body weight differences were recorded for 14 days after which, following 16 hr of withdrawal, animals were given access to a two-bottle choice of the previously presented diet and a nicotine-free diet. Spontaneous horizontal motor activity was recorded 8, 16, and 24 hr after withdrawal. By Day 14, all animals showed a significant increase in diet consumption and significant weight gain compared to Day 1. Animals consumed an average of 2.1, 6.8, or 19.5 mg/kg/day of nicotine on the low, medium, and high-nicotine diets, respectively. However, animals receiving the high-nicotine diet consumed less diet and gained less weight than the control, low, and medium nicotine groups. During only the first 4 hr of the two-bottle choice (16-20 hr postwithdrawal), the high-nicotine group consumed significantly higher amounts of nicotine base than the other groups, but also consumed more of the control diet during the first 2 hr. In a replicate experiment, animals receiving the medium-nicotine diet showed an increased consumption of the nicotine diet and increased preference for nicotine following a 14-day exposure compared to the control-fed animals and compared to a baseline preference test. Also, this group showed differences in locomotor activity consistent with other studies using an injection regimen or subcutaneuos pumps to induce dependence. Finally, animals in all three groups exhibited high plasma nicotine and cotinine (a major nicotine metabolite) levels. Because animals in all groups tolerated the diet well, gained weight, selected the nicotine diet in a choice test, and showed withdrawal symptoms, we conclude that the liquid diet proved to be a satisfactory method of inducing nicotine dependence in rats.

Differential effects of monoaminergic agonists on alcohol intake in rats fed a tryptophan-enhanced diet

The goal of the present study was to determine if enhancement of tryptophan levels in a nutritionally balanced liquid diet would affect alcohol intake in a two-bottle choice procedure. Furthermore. the monoaminergic agonists amphetamine, phentermine (dopaminergic- and noradrenergic-releasing drugs), and fenfluramine (a serotonin releaser) were administered to determine if these drugs reduced alcohol intake in animals fed the tryptophan-enhanced diet compared to those fed an alcohol-containing diet without added tryptophan. Amphetamine 0.5 and 2 mg/kg and phentermine 4 mg/kg selectively reduced alcohol intake in animals fed the tryptophan-enhanced diet; higher doses also reduced alcohol intake in animals fed the control alcohol diet. Three hours after drug administration, phentermine 2 and 4 mg/kg produced increases in consumption of the nonalcoholic diet in animals fed the control diet without affecting consumption in animals fed the tryptophan-enhanced diet. Finally, animals in the tryptophan-enhanced group gained less weight than those animals fed an identical diet without the added tryptophan. Neurochemical analysis revealed that the tryptophan-fed groups showed increased 5-HIAA concentrations and serotonin turnover in the striatum. hypothalamus, and frontal cortex compared to animals fed the control diet. The tryptophan-alcohol group also showed almost double the tryptophan levels in the hypothalamus compared to the tryptophan-isocaloric group. These results indicate that, whereas increasing tryptophan levels by itself was not sufficient to alter consumption of an alcohol-containing diet, the administration of monoaminergic agonists significantly interacted with tryptophan in a dose-dependent manner to reduce intake of an alcohol-containing diet without reducing intake of an isocaloric diet.