REduced-Carbohydrate intervention for managing Obesity and Reduction of gestational Diabetes (RECORD): A randomized controlled feasibility trial

AIM

To test the feasibility and acceptability of a reduced-carbohydrate dietary program, intended to reduce the risk of gestational diabetes.

MATERIALS AND METHODS

Fifty-one pregnant women at <20 weeks' gestation, with body mass index ≥30 kg/m2 , and a normal baseline oral glucose tolerance test (OGTT), were randomized 2:1 to an intervention or control group and followed-up until delivery. The dietary intervention aimed at providing 130-150 g carbohydrate/day. Feasibility outcomes assessed at 24-28 weeks' gestation, included adoption of the reduced-carbohydrate diet by the intervention group, and retention of all participants, assessed by completion of a second OGTT. Changes in glycemia, weight gain and dietary intake, and the maternal and neonatal outcomes were also assessed. Participants were interviewed about their experience of the intervention and the study.

RESULTS

Forty-nine of 51 participants attended the follow-up OGTT, a retention rate of 96% (95% confidence interval [CI] 86.8%-98.9%). In the intervention group, carbohydrate intake at follow-up was 190.4 (95% CI 162.5-215.6) g/day, a reduction of -24.6 (95% CI -51.5-2.4) g/day from baseline. Potentially favourable effects of the intervention on glucose control, weight gain and blood pressure were observed, but the study was not powered to detect significant differences in these. Participants found the intervention acceptable, and were content with the study processes, but some reported barriers to sustained adherence, mainly pertaining to competing priorities.

CONCLUSIONS

Retention was high, suggesting the study processes are feasible, but the carbohydrate reduction in the intervention group was small, and did not meet progression criteria, limiting the likelihood of achieving the desired goal to prevent gestational diabetes.

TRIAL REGISTRATION NUMBER

ISRCTN16235884.

Dietary intervention in gestational diabetes: a qualitative study of the acceptability and feasibility of a novel whole-diet intervention in healthcare professionals

Gestational diabetes is treated with medical nutrition therapy, delivered by healthcare professionals; however, the optimal diet for affected women is unknown. Randomised controlled trials, such as the DiGest (Dietary Intervention in Gestational Diabetes) trial, will address this knowledge gap, but the acceptability of whole-diet interventions in pregnancy is unclear. Whole-diet approaches reduce bias but require high levels of participant commitment and long intervention periods to generate meaningful clinical outcomes. We aimed to assess healthcare professionals' views on the acceptability of the DiGest dietbox intervention for women with gestational diabetes and to identify any barriers to adherence which could be addressed to support good recruitment and retention to the DiGest trial. Female healthcare professionals (n 16) were randomly allocated to receive a DiGest dietbox containing 1200 or 2000 kcal/d including at least one weeks' food. A semi-structured interview was conducted to explore participants' experience of the intervention. Interviews were audio-recorded, transcribed verbatim and analysed thematically using NVivo software. Based on the findings of qualitative interviews, modifications were made to the dietboxes. Participants found the dietboxes convenient and enjoyed the variety and taste of the meals. Factors which facilitated adherence included participants having a good understanding of study aims and sufficient organisational skills to facilitate weekly meal planning in advance. Barriers to adherence included peer pressure during social occasions and feelings of deprivation or hunger (affecting both standard and reduced calorie groups). Healthcare professionals considered random allocation to a whole-diet replacement intervention to be acceptable and feasible in a clinical environment and offered benefits to participants including convenience.

Dietary approaches to the management of type 2 diabetes (DIAMOND) in primary care: A protocol for a cluster randomised trial

INTRODUCTION

There is strong evidence that type 2 diabetes (T2D) remission can be achieved by adopting a low-energy diet achieved through total dietary replacement products. There is promising evidence that low-carbohydrate diets can achieve remission of T2D. The Dietary Approaches to the Management of type 2 Diabetes (DIAMOND) programme combines both approaches in a behaviourally informed low-energy, low-carbohydrate diet for people with T2D, delivered by nurses in primary care. This trial compares the effectiveness of the DIAMOND programme to usual care in inducing remission of T2D and in reducing risk of cardiovascular disease.

METHODS AND ANALYSIS

We aim to recruit 508 people in 56 practices with T2D diagnosed within 6 years, who are demographically representative of the UK population. We will allocate general practices, based on ethnicity and socioeconomic status, to provide usual care for diabetes or offer the DIAMOND programme. Participants in practices offering DIAMOND will see the nurse seven times over 6 months. At baseline, 6 months, and 1 year we will measure weight, blood pressure, HbA1c, lipid profile and risk of fatty liver disease. The primary outcome is diabetes remission at 1 year, defined as HbA1c < 48 mmol/mol and off glucose-lowering medication for at least 6 months. Thereafter, we will assess whether people resume treatment for diabetes and the incidence of microvascular and macrovascular disease through the National Diabetes Audit. Data will be analysed using mixed-effects generalised linear models. This study has been approved by the National Health Service Health Research Authority Research Ethics Committee (Ref: 22/EM/0074).

TRIAL REGISTRATION NUMBER

ISRCTN46961767.

Study protocol: use of a smartphone application to support the implementation of a complex physical activity intervention (+Stay Active) in women with gestational diabetes mellitus-protocol for a non-randomised feasibility study

INTRODUCTION

Physical activity (PA) interventions have a promising role in the management of gestational diabetes mellitus (GDM). Digital technologies can support PA at scale and remotely. The protocol describes a study designed to determine the feasibility and acceptability of a complex intervention; known as +Stay Active. +Stay Active combines motivational interviewing with a bespoke behaviour change informed smartphone application (Stay-Active) to augment PA levels in women with GDM.

METHODS AND ANALYSIS

This is a non-randomised feasibility study using a mixed methods approach. Participants will be recruited from the GDM antenatal clinic at the Women Centre, John Radcliffe Hospital, Oxford. Following baseline assessments (visit 1) including self-reported and device determined PA assessment (wearing a wrist accelerometer), women will be invited to participate in an online motivational interview, then download and use the Stay-Active app (Android or iOS) (visit 2). Women will have access to Stay-Active until 36 weeks gestation, when engagement and PA levels will be reassessed (visit 3). The target sample size is 60 women. Primary outcomes are recruitment and retention rates, compliance and assessment of participant engagement and acceptability with the intervention. Secondary outcomes are assessment of blood glucose control, self-reported and device determined assessment of PA, usage and structured feedback of participant's attitudes to +Stay Active, assessment of health costs and description of maternal and neonatal outcomes. This study will provide key insights into this complex intervention regarding engagement in smartphone technology and the wearing of accelerometers. These data will inform the development of a randomised controlled trial with refinements to intervention implementation.

ETHICS AND DISSEMINATION

The study has received a favourable opinion from South Central-Hampshire B Research Ethics Committee; REC reference: 20/SC/0342. Written informed consent will be obtained from all participants. Findings will be disseminated through peer-reviewed journals, conferences and seminar presentations.

TRIAL REGISTRATION NUMBER

ISRCTN11366562.

The Harry Keen Rank Nutrition Lecture 2022. Nutritional guidelines for diabetes management: Where do they come from and do they work?

Nutritional guidelines for diabetes are designed to support those living with diabetes in achieving optimal glycaemic control, reducing the risk of cardiovascular disease and maintaining quality of life. Historically, guidelines reflected current opinion and clinical practice and only relatively recently have evidence-based recommendations been published. Current nutritional guidelines for type 1 and type 2 diabetes are based on high-quality evidence including data from randomised controlled trials and prospective cohort studies and are graded by the strength of evidence. There is no evidence to support one specific dietary strategy for people with diabetes, and this is particularly true for weight reduction in those with type 2 diabetes living with overweight or obesity, where the evidence suggests that different strategies are equally successful. As a result, the emphasis of modern guidelines is on individualised, person-centred approaches. Some barriers to successful implementation include lack of dietary education and knowledge in health professionals supporting people with diabetes, and a so-called obesogenic environment that impedes dietary change. Initiatives such as education and training programmes for health professionals, and population-based interventions that promote both structural and policy change are recommended to enable those with diabetes to support dietary change and improve health.

Development and testing of a reduced carbohydrate intervention for the management of obesity and reduction of gestational diabetes (RECORD): protocol for a feasibility randomised controlled trial

INTRODUCTION

Previous trials of dietary interventions to prevent gestational diabetes mellitus (GDM) have yielded only limited success. Low-carbohydrate diets have shown promise for the treatment of type 2 diabetes, but there is no evidence to support their use in pregnancy. The aim of this study is to explore the feasibility of a moderately reduced-carbohydrate dietary intervention delivered from mid-pregnancy alongside routine antenatal care.

METHODS AND ANALYSIS

This is a feasibility randomised controlled trial (RCT) with embedded qualitative study. Sixty women who are pregnant <20 weeks' gestation, with body mass index ≥30 kg/m2 at their antenatal booking appointment, will be randomised 2:1 intervention or control (usual care) and followed up until delivery. The intervention is a moderately reduced-carbohydrate diet (~130-150 g total carbohydrate/day), designed to be delivered alongside routine antenatal appointments. Primary outcomes are measures of adoption of the diet and retention of participants. Secondary outcomes include incidence of GDM, change in markers of glycaemic control, gestational weight gain, total carbohydrate and energy intake. Process outcomes will examine resources and management issues. Exploratory outcomes include further dietary changes, quality of life, maternal and neonatal outcomes, and qualitative measures.

ETHICS AND DISSEMINATION

This trial was reviewed and approved by the South-Central Oxford B Research Ethics Committee NHS National Research Ethics Committee and the Health Research Authority (Reference: 20/SC/0442). The study results will inform whether to progress to a full-scale RCT to test the clinical effectiveness of the RECORD programme to prevent GDM in women at high risk. The findings will be published in peer-reviewed journals and presented at conferences.

TRIAL REGISTRATION NUMBER

ISRCTN16235884.

The Prembion® pre-biotic improves the impact of anti-CTLA4 immune checkpoint inhibitor in a murine model of malignant pleural mesothelioma

Objective

Immune checkpoint inhibition (ICI) therapy has revolutionized the outcome of certain cancers such as malignant pleural mesothelioma (MPM). However, patient responsiveness to this treatment remains unpredictable. Recently, a role for the gut microbiota composition has emerged for patients to generate a robust immune response against their tumors, following immunotherapy. Here, we studied the impact of Prembion®, a pre-biotic and modulator of the gut microbiota, on tumor control and lymphocyte infiltration in a murine MPM model treated by ICI.

Methods

Prembion® (diluted into drinking water) was administrated to BALBc mice for 14 days. These animals were then inoculated orthotopically with a syngeneic MPM cell line (AB12-luc cells injected in the pleura) and followed by bioluminescence imaging. We determined the tumor growth and mouse survival in different groups: untreated control, Prembion®, IgG control, anti-PDL-1, anti-CTLA4, Prembion®+anti-PDL-1 and Prembion®+anti-CTLA4. A correlation between tumor response/animal survival and MPM infiltration with CD8+ lymphocytes was also performed by immunohistochemistry.

Results

Prembion® was well tolerated and did not affect animal weight or activity. Interestingly, Prembion® was as effective as anti-PDL1 and anti-CTLA4 monotherapy on tumor control, prolonging survival by 4.0 ± 1.1 days compared to controls (p&lt;0.05). Moreover Prembion® potentiated anti-CTLA4 efficacy with a significant improvement in mouse survival of the Prembion®+anti-CTLA4 compared to controls (3.6 ± 1.1 days, p&lt;0.05). Additionally, this finding correlated with enhanced MPM infiltration by CD8+ lymphocytes compared to controls (p&lt;0.05).

Conclusion

Prembion® positively regulated the adaptive immune response against MPM and helped to improve the impact of anti-CTLA4 ICI on MPM. Further work focusing on the gut microbiome changes induced by Prembion® are ongoing to better understand the mechanisms involved.

Intrapleural hyperthermic chemotherapy induces pro-immunogenic e-selectin expression in the vasculature of malignant pleural mesothelioma

Objective

Malignant pleural mesothelioma (MPM) is a deadly disease with dismal prognosis. Prior studies combining surgery with intrapleural hyperthermic chemotherapy (IPHC) have shown improved survivals in selected patients with MPM. However, the mechanisms by which IPHC acts on MPM and its microenvironment remains unknown. Here we focus on tumor endothelial adhesion molecule expression patterns.

Methods

First, we determined the impact of IPHC on MPM tumor and vascular compartments in vitro using a novel bioincubater for hyperthermic cell culture. The cytotoxicity of normo (37 °C) / hyperthermic (42 °C for 60 minutes) cisplatin/carboplatin therapies were evaluated on four MPM (MSTO211H, H-Meso, AE17 and AB12) and one endothelial (EC-RF24) cell lines at a minimum of 24 hours using a presto-blue assay. Second, we treated endothelial cells with IPHC (60 min, 42 °C at optimized cytotoxic concentrations) and determined its impact on pro-immunogenic adhesion molecule (E-selectin, VE-cadherin, VCAM and Connexin-43) expression at 24 hours by Western blot.

Results

Tumor and endothelial cell viability decreased with increasing doses of both chemotherapeutics but was not affected by hyperthermia (IC50 with or without hyperthermia of each cell line at 24 hours reported in Figure 1A). Interestingly, endothelial cell line IC50 was much higher than that of MPM tumor cells for both chemotherapeutics (Figure 1A). Pro-immunogenic adhesion molecule E-Selectin was increased at 24 hours by IPHC with both chemotherapeutics while VE-Cadherin, VCAM and Connexin-43 were not affected (Figure 1B).

Conclusion

Hyperthermia adds no cytotoxicity to intrapleural chemotherapy. However, IPHC favors pro-immunogenic endothelial E-selectin expression. The latter could help induce patient immunity against their MPM and improve survival. Confirmation of these findings in vivo is mandatory.

The influence of nutritional state on the fatty acid composition of circulating lipid fractions: implications for their use as biomarkers of dietary fat intake

BACKGROUND

The fatty acid (FA) composition of blood can be used as an objective biomarker of dietary FA intake. It remains unclear how the nutritional state influences the FA composition of plasma lipid fractions, and thus their usefulness as biomarkers in a non-fasted state.

OBJECTIVES

To investigate the associations between palmitate, oleate and linoleate in plasma lipid fractions and self-reported dietary FA intake, and assess the influence of meal consumption on the relative abundance of these FA in plasma lipid fractions (i.e. triglyceride [TG], phospholipids [PLs] and cholesterol esters [CEs]).

DESIGN

Analysis was performed in plasma samples collected from 49 (34 males and 15 females) participants aged 26-57 years with a body mass index (BMI) between 21.6 and 34.2 kg/m², all of whom had participated in multiple study visits, thus a pooled cohort of 98 data sets was available for analysis. A subset (n = 25) had undergone nutritional interventions and was therefore used to investigate the relationship between the FA composition of plasma lipid fractions and dietary fat intake.

RESULTS

Significant (P < 0.05) positive associations were observed between dietary polyunsaturated fat and linoleate abundance in plasma CE. When investigating the influence of meal consumption on postprandial FA composition, we found plasma TG palmitate significantly (P < 0.05) decreased across the postprandial period, whereas oleate and linoleate increased. A similar pattern was observed in plasma PL, whereas linoleate abundance decreased in the plasma CE.

CONCLUSION

Our data demonstrate that the FA composition of plasma CE may be the lipid fraction to utilise as an objective biomarker when investigating recent (i.e. previous weeks-months) dietary FA intakes. In addition, we show that the consumption of a high-fat meal influences the FA composition of plasma TG, PL and CE over the course of the postprandial period, and therefore, suggest that fasting blood samples should be utilised when using FA composition as a biomarker of dietary FA intake.

Intrahepatic Fat and Postprandial Glycemia Increase After Consumption of a Diet Enriched in Saturated Fat Compared With Free Sugars

OBJECTIVE

Debate continues regarding the influence of dietary fats and sugars on the risk of developing metabolic diseases, including insulin resistance and nonalcoholic fatty liver disease (NAFLD). We investigated the effect of two eucaloric diets, one enriched with saturated fat (SFA) and the other enriched with free sugars (SUGAR), on intrahepatic triacylglycerol (IHTAG) content, hepatic de novo lipogenesis (DNL), and whole-body postprandial metabolism in overweight males.

RESEARCH DESIGN AND METHODS

Sixteen overweight males were randomized to consume the SFA or SUGAR diet for 4 weeks before consuming the alternate diet after a 7-week washout period. The metabolic effects of the respective diets on IHTAG content, hepatic DNL, and whole-body metabolism were investigated using imaging techniques and metabolic substrates labeled with stable-isotope tracers.

RESULTS

Consumption of the SFA diet significantly increased IHTAG by mean ± SEM 39.0 ± 10.0%, while after the SUGAR diet IHTAG was virtually unchanged. Consumption of the SFA diet induced an exaggerated postprandial glucose and insulin response to a standardized test meal compared with SUGAR. Although whole-body fat oxidation, lipolysis, and DNL were similar following the two diets, consumption of the SUGAR diet resulted in significant (P < 0.05) decreases in plasma total, HDL, and non-HDL cholesterol and fasting β-hydroxybutyrate plasma concentrations.

CONCLUSIONS

Consumption of an SFA diet had a potent effect, increasing IHTAG together with exaggerating postprandial glycemia. The SUGAR diet did not influence IHTAG and induced minor metabolic changes. Our findings indicate that a diet enriched in SFA is more harmful to metabolic health than a diet enriched in free sugars.

A food-based, low-energy, low-carbohydrate diet for people with type 2 diabetes in primary care: A randomized controlled feasibility trial

AIM

To examine the feasibility of a food-based, low-energy, low-carbohydrate diet with behavioural support delivered by practice nurses for patients with type 2 diabetes.

MATERIALS AND METHODS

People with type 2 diabetes and a body mass index (BMI) of ≥30 kg/m² were randomized 2:1 to intervention or control (usual care) and assessed at 12 weeks. The intervention comprised an 800-1000 kcal/day, food-based, low-carbohydrate (<26% energy) diet for 8 weeks, followed by a 4-week weight maintenance period and four 15-20-minute appointments with a nurse. Primary outcomes were feasibility of recruitment, fidelity of intervention delivery and retention of participants at 12 weeks. Secondary outcomes included change in weight and HbA1c. Focus groups explored the intervention experience.

RESULTS

Forty-eight people were screened, 33 enrolled and 32 followed-up. Mean (±SD) weight loss in the intervention group was 9.5 kg (± 5.4 kg) compared with 2 kg (± 2.5 kg) in the control group (adjusted difference - 7.5 kg [-11.0 to -4.0, P < 0.001]). Mean reduction in HbA1c in the intervention group was 16.3 mmol/mol (± 13.3 mmol/mol) compared with 0.7 mmol/mol (±4.5 mmol/mol) in the control group (difference - 15.7 mmol/mol [-24.1 to -7.3, P < 0.001]).

CONCLUSIONS

It is feasible to recruit participants to a food-based, low-energy, low-carbohydrate intervention, for practice nurses to deliver the programme in primary care, and to retain participants in both groups. There is evidence of clinically significant short-term improvements in weight and glycaemic control.

James Lind Alliance research priorities: what role do carbohydrates, fats and proteins have in the management of Type 2 diabetes, and are there risks and benefits associated with particular approaches?

AIMS

To assess the role played by carbohydrates, fat and proteins in the management of Type 2 diabetes.

BACKGROUND

Diabetes research tends to reflect the interests of academics or the pharmaceutical industry, rather than those of people living with Type 2 diabetes. The James Lind Alliance and Diabetes UK addressed this issue by defining the research priorities of people living with Type 2 diabetes. Three of the top 10 research priority questions focused on lifestyle.

METHODS

A narrative review was undertaken with a structured search strategy using three databases. Search terms included the three macronutrients and Type 2 diabetes. No restrictions were placed on macronutrient quantity or length of study follow-up. Outcomes included changes in HbA_1c , body weight, insulin sensitivity and cardiovascular risk.

RESULTS

There is no strong evidence that there is an optimal ratio of macronutrients for improving glycaemic control or reducing cardiovascular risk. Challenges included defining the independent effect of macronutrient manipulation and identifying the effects of macronutrients, independent of foods and dietary patterns. Extreme intakes of macronutrients may be associated with health risks.

CONCLUSIONS

It is challenging to formulate food-based guidelines from studies based on macronutrient manipulation. Structured education should be offered to support individuals in discovering their optimal, individual dietary approach. Recommendations for dietary guidelines should be expressed in terms of foods and not macronutrients.

Dietary Approaches to the Management Of type 2 Diabetes (DIAMOND): protocol for a randomised feasibility trial

INTRODUCTION

Some clinicians have observed that low-carbohydrate, low-energy diets can improve blood glucose control, with reports of remission from type 2 diabetes in some patients. In clinical trials, support for low-carbohydrate, low-energy diets has been provided by specialist staff and these programmes are unsuitable for widespread deployment in routine primary care. The aim of this trial is to test whether a newly developed behavioural support programme can effectively deliver a low-energy, low-carbohydrate diet in a primary care setting.

METHODS AND ANALYSIS

This is a feasibility randomised controlled trial (RCT) with embedded qualitative study. Thirty adult patients with type 2 diabetes and body mass index ≥30 kg/m² in 2-4 general practices will be randomised 2:1 intervention or control and followed up over 12 weeks. The intervention diet comprises 8 weeks of a low-carbohydrate food-based diet providing around 800 kcal/day, followed by 4 weeks of weight maintenance. This programme will be delivered by practice nurses, who will also support patients through goal-setting, motivation and self-monitoring across four appointments, and provide a self-help booklet with recipes, shopping lists and other behavioural support. Primary outcome measures of feasibility will be met if CIs do not cross the following proportions: that 60% of intervention group participants attempt the dietary intervention, healthcare professionals conduct the intervention delivery session with at least 60% of essential elements present and 60% of participants attend the final follow-up session. Secondary outcome measures will assess process and qualitative measures, as well as exploratory outcomes including change in haemoglobin A1c and change in weight.

ETHICS AND DISSEMINATION

This study has been granted ethical approval by the National Research Ethics Service, South Central Oxford B Research Ethics Committee (ref: 18/SC/0071). The study results will inform whether to progress to a full-scale RCT to test the efficacy of offering this programme for patients with type 2 diabetes in primary care.

TRIAL REGISTRATION NUMBER

ISRCTN62452621; Pre-results.

Low Carbohydrate Diets and Type 2 Diabetes: What is the Latest Evidence?

INTRODUCTION

Low carbohydrate diets are again in the spotlight and have been identified as particularly appropriate for people with type 2 diabetes. There is confusion amongst both health professionals and people with diabetes about the suitability of these diets. This review aims to provide an overview of the latest evidence and to explore the role of low carbohydrate diets for people with type 2 diabetes.

METHODS

An electronic search of English language articles was performed using MEDLINE (2010-May 2015), EMBASE (2010-May 2015), and the Cochrane Central Register of Controlled Trials (2010-May 2015). Only randomized controlled trials comparing interventions evaluating reduced carbohydrate intake with higher carbohydrate intake in people with diagnosed type 2 diabetes were included. Primary outcomes included weight, glycated hemoglobin, and lipid concentrations.

RESULTS

Low carbohydrate diets in people with type 2 diabetes were effective for short-term improvements in glycemic control, weight loss, and cardiovascular risk, but this was not sustained over the longer term. Overall, low carbohydrate diets failed to show superiority over higher carbohydrate intakes for any of the measures evaluated including weight loss, glycemic control, lipid concentrations, blood pressure, and compliance with treatment.

CONCLUSION

Recent studies suggest that low carbohydrate diets appear to be safe and effective over the short term, but show no statistical differences from control diets with higher carbohydrate content and cannot be recommended as the default treatment for people with type 2 diabetes.

Alcohol health literacy in young adults with type 1 diabetes and its impact on diabetes management

AIMS

To investigate the knowledge of alcohol and carbohydrate content of commonly consumed alcoholic drinks among young adults with Type 1 diabetes and to explore alcohol consumption while identifying diabetes self-management strategies used to minimize alcohol-associated risk.

METHOD

We conducted an open-access, multiple-choice web survey to investigate knowledge of alcohol and carbohydrate content of typical alcoholic drinks using images. Respondents to the survey also recorded their current alcohol consumption and diabetes self-management strategies when drinking.

RESULTS

A total of 547 people aged 18-30 years responded to the survey (341 women; 192 men; mean (sd) age 24.5 (3.7) years), of whom 365 (66.7%) drank alcohol. In all, 84 (32.9%) women and 31 (22.6%) men scored higher than the cut-off score for increased-risk drinking. Knowledge accuracy of alcohol units was poor: only 7.3% (n = 40) correctly identified the alcohol content of six or more out of 10 drinks. Knowledge of carbohydrate content was also poor: no respondent correctly identified the carbohydrate content of six or more out of 10 drinks. Various and inconsistent strategies to minimize alcohol-associated risk were reported.

CONCLUSIONS

Alcohol consumption was common among the survey respondents, but knowledge of alcohol and carbohydrate content was poor. Greater alcohol-related health literacy is required to minimize alcohol-associated risk. Further research should help develop effective strategies to improve health literacy and support safe drinking for young adults with Type 1 diabetes.

Biochemical markers of bone metabolism and risk of dorsal metacarpal disease in 2-year-old Thoroughbreds

REASONS FOR PERFORMING STUDY

Dorsal metacarpal disease (DMD) is a common problem in 2-year-old racehorses and results in loss of a significant number of days from training. Biochemical markers of bone cell activity measured early in the training season could have value for identifying 2-year-old Thoroughbred racehorses that develop DMD.

OBJECTIVES

To determine the association between serum concentrations of osteocalcin, the carboxyterminal propeptide of type I collagen (PICP) and the carboxyterminal cross-linked telopeptide of type I collagen (ICTP) measured early in the training season and the risk of DMD.

METHODS

Blood samples were collected from 165 two-year-old Thoroughbreds during late November/early December. Osteocalcin and PICP were measured as markers of bone formation, and ICTP as a marker of bone resorption. Training and veterinary records for each horse were monitored over the following training/racing season (10 months). Cases were defined as an episode where signs of DMD were sufficiently severe for a horse to miss at least 5 consecutive days of training. Classification tree and logistic regression analysis were used to identify the most important factors suitable for prediction of DMD risk.

RESULTS

There were 24 cases of DMD during the season (14.6% cumulative incidence), with an average time to recognition of approximately 6 months (May). The earliest recognised case was in February and the latest in September. Osteocalcin and ICTP concentrations in the early stages of the training season were significantly higher in horses that subsequently developed DMD (P = 0.017 and 0.019, respectively). DMD cases were also significantly older compared to noncases (21.04 vs. 20.44 months, P = 0.023). Using a multivariable logistic regression model, it was possible to postulate a set of diagnostic rules to predict the likelihood of DMD injury during the season. This suggested that horses with ICTP concentrations above 12365 ug/l and older than 20.5 months are 2.6 times more likely to develop DMD.

CONCLUSIONS

The measurement of the bone resorption marker ICTP could be useful for identification of 2-year-olds at increased risk of developing DMD.

POTENTIAL RELEVANCE

These findings, together with other strategies such as modification of training regimens, e.g. early introduction of short distances of high-speed exercise into the training programme, could help reduce the days lost to training as a result of DMD.

Circulating fibroblast growth factor 21 is induced by peroxisome proliferator-activated receptor agonists but not ketosis in man

CONTEXT

Murine fibroblast growth factor (FGF) 21 is a nutritionally regulated hormone secreted by the liver principally in response to peroxisome proliferator-activated receptor-alpha (PPAR alpha) activation, which plays a critical role in regulating metabolism during ketosis. FGF21 is also a PPAR gamma target gene in mouse adipose tissue. Little information is available on FGF21 functions in humans.

OBJECTIVE

The aim of the study was to measure plasma FGF21 during fasting, ketogenic diet, and PPAR agonist treatment in humans.

DESIGN AND SETTING

We conducted a prospective study involving three patient groups at two university hospitals.

PATIENTS

Eight healthy male volunteers underwent a 48-h period of starvation followed by 24-h refeeding (group 1); seven obese individuals were allocated to a low-carbohydrate diet for 3 months (group 2); and three groups of healthy, overweight or obese male volunteers received treatment with a PPAR alpha (20 microg/d GW590735) (n=6), PPAR delta (10 mg/d GW501516) (n=6), or PPAR gamma agonist (rosiglitazone) (n=10) for 2 wk (group 3).

MAIN OUTCOME MEASURES

Fasting plasma FGF21 and serum 3-hydroxybutyrate were measured.

RESULTS

There was no significant variation in human plasma FGF21 during fasting and refeeding. A 3-month ketogenic diet was associated with a 42% decline in plasma FGF21 levels. Circulating FGF21 increased significantly in response to treatment with PPAR alpha (39%) and PPAR delta (32%), but not PPAR gamma agonists.

CONCLUSION

FGF21 does not play a major role in regulating the fasting response or ketosis in man. However, plasma FGF21 is elevated in response to pharmacological activation of PPAR alpha and PPAR delta and may contribute to the beneficial metabolic effects observed in response to pharmacotherapy with these compounds.

Insulin for type 2 diabetes: choosing a second-line insulin regimen

Guidance has been published on the choice of initial insulin regimen for patients with type 2 diabetes [NPH (isophane) insulin or a long-acting insulin analogue] but not on how to choose a second regimen when glycaemic control becomes unsatisfactory.

AIMS

To develop pragmatic clinical guidance for choosing a second-line insulin regimen tailored to the individual needs of patients with type 2 diabetes after failure of first-line insulin therapy.

METHODS

Formulation of a consensus by expert panel based on published evidence and best clinical practice, taking into account patient preferences, lifestyle and functional capacity.

RESULTS

Six patient-dependent factors relevant to the choice of second-line insulin regimen and three alternative insulin regimens (twice-daily premixed, basal-plus and basal-bolus) were identified. The panel recommended one or more insulin regimens compatible with each factor, emphasising the fundamental importance of a healthy lifestyle that includes exercise and weight reduction. These recommendations were incorporated into an algorithm to provide pragmatic guidance for clinicians.

CONCLUSION

The three alternative insulin regimens offer different benefits and drawbacks and it is important to make the right choice to optimise outcomes for patients.

Hybrid Lumbar Fusion: A clinical and radiological review at 2 years

We report on our first 20 patients treated with hybrid lower lumbar stabilization, in which one or more segments were treated with caged interbody fusion by PLIF technique and one or more adjacent segments were stabilized using GRAF instrumentation.

The indications for interbody fusion included spondylolysis; previous failed disc surgery, and primary discopathy with positive discography and/or active modic signal on MRI.

The indication for flexible stabilization of adjacent segments was for disc degeneration on MRI scanning with or without evidence of posterior annular tear.

This was a prospective study with clinical evaluation using VAS pain scales and Oswestry disability score. All patients were reviewed by an independent consultant radiologist to assess integrity of the implant after two years and underwent CT scanning to assess progression of the caged fusion. There were no instances of failed fusion in this group and no cases of implant failure.

Long-term follow up of sequential mobilisation and autologous transplantation with CD34-selected cells in multiple myeloma: a multimodality approach

BACKGROUND

Even after high dose chemotherapy (HDT) and autologous haemopoietic stem cell transplantation, the majority of patients with multiple myeloma eventually relapse.

AIM

The aim of the present study was to study the -feasibility and outcome of delivering a regimen including in vivo and in vitro purging and double HDT in patients with multiple myeloma.

METHODS

Thirty-four patients with advanced multiple myeloma were enrolled in a program of vincristine, doxorubicin and dexamethasone chemotherapy, high dose cyclophosphamide/granulocyte macrophage colony stimulating factor (GM-CSF) stem cell mobilisation, CD34 selection of harvested stem cells (in vitro purging), double HDT (cyclophosphamide/epirubicin in the first, busulphan/melphalan in the second) rescued by CD34(+)-selected cells, the second rescue using cells harvested following the first HDT (in vivo purging) and interferon maintenance.

RESULTS

Forty-four per cent of patients completed the program. Fifty-three per cent of withdrawals were as a result of insufficient stem cells. This correlated to previous chemotherapy. Therapy-related mortality was 6%. CD34(+) selection achieved more than a 2-log reduction of CD38(++) cells; in vivo purging achieved 80%. Although similar numbers of CD34(+) cells were reinfused at both HDT, platelet recovery was slower after the second HDT. Additional complete remissions were achieved after each phase of therapy, 3% at the end of vincristine, doxorubicin and dexamethasone and 33% after completing planned HDT. Factors associated with longer overall survival included age less than 60 years (P = 0.044), serum beta-2-microglobulin below 3 micro gamma/L at entry (P = 0.042) and less than 2 months between the two HDT (P = 0.024). The only factor associated with a longer event-free survival was less than 2 months between HDT on study (P = 0.038).

CONCLUSIONS

(i) dose intensification with two HDT delivered within 2 months might be associated with a better patient outcome, (ii) early mobilisation should be incorporated in multiple myeloma HDT programs and (iii) higher CD34(+) doses may be required for tandem transplants.

Selected CD34 blood cell allografts for older patients: low transplant-related mortality, graft failure and acute GvHD

BACKGROUND

Early transplant mortality is related to acute GvHD, which this study in older patients (40 to 60 years) decreased by reducing the graft T-cell number while maintaining a high CD34 cell number--by positive CD34 cell selection. Potential increased risk of relapse is addressed by giving donor leucocyte infusion (DLI) post-transplant.

METHODS

CD34 cells selected by Isolex devices from leukophereses obtained from Filgrastim-treated matched sibling donors were transplanted and DLI given later if there was no GvHD.

RESULTS

Selection of CD34 cells achieved a median of 5.2 million cells/kg, with minimum target for transplantation achieved in 17 of 21 donors. Median CD3 cell number was 0.24 million/kg. Engraftment was rapid and graft failure rare. Transplant-related mortality was low (6% at 3 months). Acute GvHD of >or=Grade 2 occurred in only two patients (12.5%). DLI were given to only six patients who had resolved Grade 1 or no GvHD. Eight of the 17 patients relapsed, including three of the six who had DLI. Extensive chronic GvHD developed in six of 12 evaluable patients, two of these had received DLI. Seven of the 17 patients (41%) are alive at median follow-up of 56 months.

CONCLUSION

CD34 selection allows transplantation of high numbers of CD34 cells with low CD3 cell count, reducing early mortality in patients 40-60 years old because of rapid hemopoietic reconstitution and low acute GvHD incidence. Administration of DLI was often precluded by low-grade acute GvHD.

Nutrition and diabetes control: advice for non-dietitians

Diabetes mellitus affects 2-4% of the UK population and its prevalence is predicted to double by 2010. It has been widely acknowledged that dietary therapy can reduce the risk of complications in people with diabetes. However, as there are insufficient diabetes specialist dietitians to deliver dietary advice to all people with diabetes, the burden of care will fall on the primary care team. Dietary advice given to people with diabetes by healthcare professionals needs to be consistent. As recommendations change with new evidence, professionals have a duty to update their knowledge. This article reviews current nutritional recommendations from the UK, Europe and the USA and offers suggestions for translating dietary theory into practice. It emphasizes the importance of an individual approach, taking into account usual eating patterns, lifestyle, age, culture and medication.

Novel post-replicative DNA modification in Streptomyces: analysis of the preferred modification site of plasmid pIJ101

Both Streptomyces lividans and Streptomyces avermitilis have the ability to site specifically modify their DNA, rendering it susceptible to in vitro Tris-dependent double-strand cleavage. We have cloned a 160 bp fragment containing the preferred modification site of plasmid pIJ101 and, employing an in vitro primer extension assay, determined that the modifications occur at guanine residues on either strand separated by 3 bp. These guanines are located within a 6 bp palindromic 'core' sequence. A cloned copy of a 35 bp region of the plasmid containing this core sequence was not recognized by the modifying activity in vivo. To further investigate the nature of the site specificity a set of deletion mutants of the 160 bp sequence were analysed. This revealed that a substantial portion of this sequence is essential for authentic modification. The essential region contains three 13 bp direct repeats, the central one containing the core sequence, while the left-hand and right-hand copies overlap two potential stem-loop structures. Deletion of either left- or right-hand repeat structures abolishes modification within the core sequence, although the left-hand deletion resulted in modification at a secondary site within the right-hand direct repeat. These data support a post-replicative mechanism of modification, underlined by the observation that the modifications are not detected in single-stranded plasmid replication intermediates.

Myeloma stem cells in autografting in multiple myeloma

Autologous transplantation has been used increasingly over the last 10 years for the treatment of multiple myeloma. As is the case in other cancers treated by high-dose therapy and stem cell rescue, the contribution of occult tumor cells in the graft to relapse posttransplant remains to be resolved. In this report, we review the biology and differentiation of plasma cells in the context of their significance as an origin of relapse in multiple myeloma.

An incremental response to high-dose therapy in multiple myeloma

Results of conventional chemotherapy for multiple myeloma are disappointing. High-dose chemoradiotherapy with auto-transplantation is increasingly reported and some results are encouraging. We report the results of peripheral blood stem cell transplantation (PBSCT) for multiple myeloma at a single institution over a 6-year period. Forty patients, including 18 de novo patients, received debulking chemotherapy consisting of vincristine, adriamycin, and dexamethasone or methyl-prednisolone followed by stem cell mobilization with high-dose cyclophosphamide. Twenty-nine patients received PBSCT following high-dose chemoradiotherapy. Following PBSCT 92% of evaluable patients obtained at least a partial remission and 29% reached complete remission. Objective treatment responses, defined as at least a 50% reduction in serum paraprotein or marrow plasma cells, were observed following each treatment step of debulking chemotherapy, mobilization and PBSCT in 50, 42 and 71% of patients, respectively. The median overall survival from diagnosis in patients transplanted was 50 months and the median overall and progression-free survivals following transplant were 26 and 18 months, respectively. Median follow-up was 28 months. Overall treatment-related mortality was 20% but was significantly lower in de novo vs previously treated patients at 6 and 33% respectively (P = 0.027). De novo patients were more likely to obtain complete remission and had a longer overall survival following transplant but overall survival from diagnosis was similar to previously treated patients. A low serum B2M before mobilization predicted a longer progression-free survival. PBSCT needs to be considered early following diagnosis to maximise treatment response and reduce the high treatment-related mortality seen in heavily pretreated patients. In this treatment program a dose response effect in multiple myeloma was observed possibly suggesting that more intensive therapy than a single transplant may effect greater disease response.

Inducible transposition in Streptomyces lividans of insertion sequence IS6100 from Mycobacterium fortuitum

Transposition of IS6100, originally isolated as part of the compound transposon Tn610 from Mycobacterium fortuitum, was tested in the related actinomycete Streptomyces lividans. Cointegrate formation was observed, as expected for this IS6-related element, and involved apparent random integration of the temperature-sensitive vector carrying IS6100 and concomitant duplication of the insertion sequence. This establishes that a single copy of the insertion sequence can promote transposition and is a precedent for the functioning of a heterologous transposable element in Streptomyces. Transposition could be induced 100-fold by external transcription emanating from a copy of the thiostrepton-inducible promoter ptipA located outwith the insertion sequence and resulting in overexpression of the transposase gene. Thus, in contrast to other prokaryotic transposable elements, IS6100 appears to have no effective means of protecting itself from external activation.

Wound healing on the lower leg after radiotherapy or cryotherapy of Bowen's disease and other malignant skin lesions

To investigate lower leg wound healing after treatment of skin tumours, the results of external beam radiotherapy were assessed for 141 lesions in 91 patients. Poor healing or failure to heal occurred in 33%, and was related to the age of the patients, the diameter of the radiotherapy field, and the dose and energy of radiotherapy used. No effect of fractionation on healing was apparent, but only 14% of patients were exposed to regimens with a nominal standard dose of over 1800 rets. Age > 90 years, field diameter > 4 cm and dose > 3000 cGy were all associated with a risk of impaired healing of over 50%. The most frequent single diagnosis (59 lesions) in the radiotherapy patients was Bowen's disease. The results of wound healing in these patients were compared with the results of cryotherapy to 82 lower leg Bowen's disease lesions in 49 dermatology patients. Only 2% of the cryotherapy lesions failed to heal compared with 20% of the radiotherapy wounds, although 6% of cryotherapy cases had local recurrence compared with none in the radiotherapy group. Serial overlapping cryotherapy fields of up to 2 cm diameter were shown to be a valid treatment option for Bowen's disease, as no patients had therapy-related failure to heal. To avoid the requirement for potentially more difficult post-radiotherapy salvage surgery, intra-epidermal non-invasive skin tumours > 4 cm in diameter on the lower leg are probably initially best treated by a primary surgical procedure or by staged cryotherapy. Invasive carcinoma of > 4 cm diameter is best treated by surgical excision.(ABSTRACT TRUNCATED AT 250 WORDS)

Tris-dependent oxidative DNA strand scission during electrophoresis

The DNA of two Streptomyces species contains site-specific labile modifications. During gel electrophoresis the DNA can undergo Tris-dependent strand scission at the positions of these modifications. Our investigations into the nucleolytic activity which reacts with the modifications implicate a peracid derivative of Tris formed at the anode; the kinetics of production and decay of this activity were followed using both a DNA cleavage assay and a reduced methyl viologen assay to measure oxidant. Anode activation could be chemically mimicked by addition of peracetic acid to Tris buffers. We tested the DNA cleavage activity of several other compounds after anode or chemical activation; we used an analogue of Tris lacking a primary amine group and also several reagents known to promote DNA strand cleavage by amine-catalysis at abasic sites. Anode generation of oxidant could be detected for compounds containing either hydroxyl or carboxyl groups. However, DNA cleavage activity correlated with oxidant formation only for those compounds also containing primary amine groups. These results support a mechanism of DNA strand scission at modification sites via concerted peracid-mediated oxidative and amine-catalysed reactions. The novel finding of Tris-dependent formation of a long-lived reactive oxidant at the anode suggests that this compound is unsuited as an electrophoresis buffer for certain biological macromolecules.

Characterization of a Streptomyces-lividans-type site-specific DNA modification system in the avermectin-producer Streptomyces avermitilis permits investigation of two novel giant linear plasmids, pSA1 and pSA2

The degradation of Streptomyces avermitilis DNA samples analysed by conventional pulsed-field gel electrophoresis was shown to be due to Tris-dependent, double-strand cleavage. Using alternative electrophoretic conditions, separation of intact DNA molecules was achieved, permitting the identification of two novel giant linear plasmids: the 100 kb pSA1 and 250 kb pSA2. Use of pSA2 DNA as a probe showed that pSA1 does not cross-hybridize, indicating that the plasmids are not closely related. The site-specificity of the DNA modifications, which render the DNA susceptible to Tris-dependent cleavage, was found to be essentially identical to that of similar modifications found in the DNA of S. lividans.

Carotid artery stenosis following adjuvant radiotherapy for a parotid pleomorphic adenoma

Carotid artery stenosis following radiotherapy for head and neck cancer is probably underdiagnosed. We report a symptomatic case and suggest that greater awareness of the condition should result in suitable investigation and appropriate medical or surgical treatment.

Spinal cord compression: prognosis and implications for treatment fractionation

A review of 158 cases of metastatic extradural spinal cord compression referred to three radiotherapy departments shows that the median survival time is less than 3 months, that recovery of motor and sphincter function is uncommon, and that low fraction (2-5) regimens have a similar clinical outcome to more protracted regimens.

Tris-dependent site-specific cleavage of Streptomyces lividans DNA

During conventional gel electrophoresis, Streptomyces lividans DNA undergoes site-specific double-strand cleavage at the positions of closely opposed unstable modifications introduced into the DNA in vivo. We investigated this electrophoretic instability and demonstrated that it was dependent on Tris. Tris buffer was activated at the anode to generate a nucleolytic species; prior to activation, Tris was not able to cleave the DNA. The nucleolytic species was shown to react with thiourea, which could thus protect the DNA from strand cleavage. Non-degradative electrophoresis of the DNA could also be achieved in an alternative buffer such as Hepes.

Genetic instability and DNA amplification in Streptomyces lividans 66

Streptomyces lividans 66 exhibits genetic instability, involving sequential loss of resistance to chloramphenicol (Cams) and subsequent mutation of argG. Associated with this instability is the amplification of a 5.7-kilobase (kb) amplified DNA sequence (ADS). We have characterized a second, independent pathway of genetic instability, involving sequential loss of resistance to tetracycline (Tets) followed by mutation in nitrogen assimilation (Ntr). We detected DNA amplification in many of these mutant strains, as well as other reiterations coresident with the 5.7-kb ADS in Cams Arg mutants. However, in contrast to the 5.7-kb ADS, none of the novel elements were observed to amplify at high frequency. The mutation of argG is due to a deletion, one endpoint of which is defined by the 5.7-kb ADS. This amplification derives from a structure, the tandemly duplicated amplifiable unit of DNA (AUD), present in the wild-type genome. We found that progenitor strains containing just a single-copy AUD failed to reproducibly generate amplification of this element in Cams argG mutants, and DNA deletion endpoints proximal to the element were found to be unspecific. These results suggest that a duplicated AUD structure is required for high-frequency amplification and that this reiteration can subsequently buffer the extent of deletion formation in the relevant chromosomal region.

Relationship of an unstable argG gene to a 5.7-kilobase amplifiable DNA sequence in Streptomyces lividans 66

The relationship between an unstable argG gene and a 5.7-kilobase (kb) amplifiable DNA sequence in Streptomyces lividans 66 was investigated. Spontaneous, high-frequency Arg mutants deleted for this gene typically contain 200 to 300 copies of the tandemly reiterated sequence. A library of S. lividans 66 (strain 1326) wild-type genomic DNA was prepared in the vector lambda Charon 35. Chromosome walking over 44 kb established that argG is located 25 kb distant from a duplicated amplifiable DNA structure. A sequence was characterized, located farther distal from the amplifiable structure, containing strong homology with an internal sequence of the amplifiable DNA, which may have a role in the deletion of argG. Genetic mapping showed that argG and the 5.7-kb amplifiable sequence are linked to another unstable gene, determining chloramphenicol resistance (Camr) and that together these genes may be located in a silent chromosomal arc.

Transposon-encoded site-specific recombination: nature of the Tn3 DNA sequences which constitute the recombination site res

The tnpR gene of transposon Tn3 encodes a site-specific recombination enzyme that acts at res, a DNA region adjacent to tnpR, to convert co-integrate intermediates of interreplicon transposition to the normal transposition end-products. We have used two complementary approaches to study the nature of the Tn3 recombination region, res. Firstly, the DNA-binding sites for tnpR protein were determined in DNase I protection experiments. These identified a 120-bp region between the tnpA and tnpR genes that can be subdivided into three separate protein-binding sites. Genetic dissection experiments indicate that few, if any, other sequences in addition to this 120-bp region are required for res function. Moreover, we have shown that the two directly repeated res regions within a molecule are unequal partners in the recombination reaction: a truncated res region, which is unable to recombine with a second identical res region, can recombine efficiently with an intact res region. This demonstration, along with the observation that tnpR/res recombination acts efficiently on directly repeated res regions within a molecule but inefficiently both on inverted res regions in the same molecule and in the fusion reaction between res regions in different molecules, leads us to propose that one-dimensional diffusion (tracking) of tnpR protein along DNA is used to locate an initial res region, and then to bring a second directly repeated res region into a position that allows recombination between the res regions.