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Reaction of the normal isomer of [[[B.sub.20][H.sub.18]].sup.2-] and the protected thiol anion, [[SC(O)OC[(C[H.sub.3]).sub.3]].sup.-], produces an unexpected isomer of [[[B.sub.20][H.sub.17]SC(O)OC[(C[H.sub.3]).sub.3]].sup.4-] directly and in good yield. The isomer produced under mild conditions is characterized by an apical-apical boron atom intercage connection as well as the location of the thiol substituent on an equatorial belt adjacent to the terminal boron apex. Although the formation of this isomer from nucleophilic attack of the normal isomer of [[[B.sub.20][H.sub.18]].sup.2-] has not been reported previously, the isomeric assignment has been unambiguously confirmed by one-dimensional and two-dimensional 11B NMR spectroscopy. Deprotection of the thiol substituent under acidic conditions produces a protonated intermediate, [[[B.sub.20][H.sub.18]SH].sup.3-], which can be deprotonated with a suitable base to yield the desired product, [[[B.sub.20][H.sub.17]SH].sup.4-]. The sodium salt of the resulting [[[B.sub.20][H.sub.17]SH].sup.4-] ion has been encapsulated in small, unilamellar liposomes, which are capable of delivering their contents selectively to tumors in vivo, and investigated as a potential agent for boron neutron capture therapy. The biodistribution of boron was determined after intravenous injection of the liposomal suspension into BALB/c mice bearing EMT6 mammary adenocarcinoma. At low injected doses, the tumor boron concentration increased throughout the time-course experiment, resulting in a maximum observed boron concentration of 46.7 [[micro]gram] of B per g of tumor at 48 h and a tumor to blood boron ratio of 7.7. The boron concentration obtained in the tumor corresponds to 22.2% injected dose (i.d.) per g of tissue, a value analogous to the most promising polyhedral borane anions investigated for liposomal delivery and subsequent application in boron neutron capture therapy.

Abstract Background Hundreds of thousands of volunteers take part in medical research, but many will never hear from researchers about what the study revealed. There is a growing demand for the results of randomised trials to be fed back to research participants both for ethical research practice and for ensuring their co-operation in a trial. This study aims to determine participants' preferences for type of leaflet (short versus long) used to summarise the findings of a randomised trial; and to test whether certain characteristics explained participants' preferences. Methods 553 participants in a randomised trial about General Practitioners' access to Magnetic Resonance Imaging for patients presenting with suspected internal derangement of the knee were asked in the final follow-up questionnaire whether they would like to be fed back the results of the trial. Participants who agreed to this were included in a postal questionnaire survey asking about their preference, if any, between a short and a long leaflet and what it was about the leaflet that they preferred. Multinomial logistic regression was used to test whether certain demographics of responding participants along with treatment group explained whether a participant had a preference for type of leaflet or no preference. Results Of the participants who returned the final follow-up questionnaire, 416 (88%) agreed to receive the results of the trial. Subsequently 132 (32%) participants responded to the survey. Most participants preferred the longer leaflet (55%) and the main reasons for this were the use of technical information (94%) and diagrams (89%). There was weak evidence to suggest that gender might explain whether participants have a preference for type of leaflet or not (P = 0.084). Conclusions Trial participants want to receive feed back about the results and appear to prefer a longer leaflet. Males and females might require information to be communicated to them differently and should be the focus of further research. Trial registration The trial is registered with http://www.isrctn.org/ and ID is ISRCTN76616358.

Abstract Background There is a wealth of evidence regarding the detrimental impact of excessive alcohol consumption. In older populations excessive alcohol consumption is associated with increased risk of coronary heart disease, hypertension, stroke and a range of cancers. Alcohol consumption is also associated with an increased risk of falls, early onset of dementia and other cognitive deficits. Physiological changes that occur as part of the ageing process mean that older people experience alcohol related problems at lower consumption levels. There is a strong evidence base for the effectiveness of brief psychosocial interventions in reducing alcohol consumption in populations identified opportunistically in primary care settings. Stepped care interventions involve the delivery of more intensive interventions only to those in the population who fail to respond to less intensive interventions and provide a potentially resource efficient means of meeting the needs of this population. Methods/design The study design is a pragmatic prospective multi-centre two arm randomised controlled trial. The primary hypothesis is that stepped care interventions for older hazardous alcohol users reduce alcohol consumption compared with a minimal intervention at 12 months post randomisation. Potential participants are identified using the AUDIT questionnaire. Eligible and consenting participants are randomised with equal probability to either a minimal intervention or a three step treatment approach. The step treatment approach incorporates as step 1 behavioural change counselling, step 2 three sessions of motivational enhancement therapy and step 3 referral to specialist services. The primary outcome is measured using average standard drinks per day and secondary outcome measures include the Drinking Problems Index, health related quality of life and health utility. The study incorporates a comprehensive economic analysis to assess the relative cost-effectiveness of the interventions. Discussion The paper presents a protocol for the first pragmatic randomised controlled trial evaluating the effectiveness and cost-effectiveness of stepped care interventions for older hazardous alcohol users in primary care. Trial registration ISRCTN52557360

Abstract Background Poor response rates to postal questionnaires can introduce bias and reduce the statistical power of a study. To improve response rates in our trial in primary care we tested the effect of introducing an unconditional direct payment of £5 for the completion of postal questionnaires. Methods We recruited patients in general practice with knee problems from sites across the United Kingdom. An evidence-based strategy was used to follow-up patients at twelve months with postal questionnaires. This included an unconditional direct payment of £5 to patients for the completion and return of questionnaires. The first 105 patients did not receive the £5 incentive, but the subsequent 442 patients did. We used logistic regression to analyse the effect of introducing a monetary incentive to increase the response to postal questionnaires. Results The response rate following reminders for the historical controls was 78.1% (82 of 105) compared with 88.0% (389 of 442) for those patients who received the £5 payment (diff = 9.9%, 95% CI 2.3% to 19.1%). Direct payments significantly increased the odds of response (adjusted odds ratio = 2.2, 95% CI 1.2 to 4.0, P = 0.009) with only 12 of 442 patients declining the payment. The incentive did not save costs to the trial – the extra cost per additional respondent was almost £50. Conclusion The direct payment of £5 significantly increased the completion of postal questionnaires at negligible increase in cost for an adequately powered study.

Abstract Background Though new technologies like Magnetic Resonance Imaging (MRI) may be accurate, they often diffuse into practice before thorough assessment of their value in diagnosis and management, and of their effects on patient outcome and costs. MRI of the knee is a common investigation despite concern that it is not always appropriate. There is wide variation in general practitioners (GPs) access to, and use of MRI, and in the associated costs. The objective of this study was to resolve uncertainty whether GPs should refer patients with suspected internal derangement of the knee for MRI or to an orthopaedic specialist in secondary care. Methods/Design The design consisted of a pragmatic multi-centre randomised trial with two parallel groups and concomitant economic evaluation. Patients presenting in general practice with suspected internal derangement of the knee and for whom their GP was considering referral to an orthopaedic specialist in secondary care were eligible for inclusion. Within practices, GPs or practice nurses randomised eligible and consenting participants to the local radiology department for an MRI examination, or for consultation with an orthopaedic specialist. To ensure that the waiting time from GP consultation to orthopaedic appointment was similar for both trial arms, GPs made a provisional referral to orthopaedics when requesting the MRI examination. Thus we evaluated the more appropriate sequence of events independent of variations in waiting times. Follow up of participants was by postal questionnaires at six, twelve and 24 months after randomisation. This was to ensure that the evaluation covered all events up to and including arthroscopy. Discussion The DAMASK trial should make a major contribution to the development of evidence-based partnerships between primary and secondary care professionals and inform the debate when MRI should enter the diagnostic pathway.

Background: Poor response rates to postal questionnaires can introduce bias and reduce the statistical power of a study. To improve response rates in our trial in primary care we tested the effect of introducing an unconditional direct payment of £5 for the completion of postal questionnaires. Methods: We recruited patients in general practice with knee problems from sites across the United Kingdom. An evidence-based strategy was used to follow-up patients at twelve months with postal questionnaires. This included an unconditional direct payment of £5 to patients for the completion and return of questionnaires. The first 105 patients did not receive the £5 incentive, but the subsequent 442 patients did. We used logistic regression to analyse the effect of introducing a monetary incentive to increase the response to postal questionnaires. Results: The response rate following reminders for the historical controls was 78.1% (82 of 105) compared with 88.0% (389 of 442) for those patients who received the £5 payment (diff = 9.9%, 95% CI 2.3% to 19.1%). Direct payments significantly increased the odds of response (adjusted odds ratio = 2.2, 95% CI 1.2 to 4.0, P = 0.009) with only 12 of 442 patients declining the payment. The incentive did not save costs to the trial - the extra cost per additional respondent was almost £50. Conclusion: The direct payment of £5 significantly increased the completion of postal questionnaires at negligible increase in cost for an adequately powered study. [ABSTRACT FROM AUTHOR]