Inducible liver-specific knockdown of protein tyrosine phosphatase 1B improves glucose and lipid homeostasis in adult mice

AIMS/HYPOTHESIS

Protein tyrosine phosphatase 1B (PTP1B) is a key negative regulator of insulin signalling. Hepatic PTP1B deficiency, using the Alb-Cre promoter to drive Ptp1b deletion from birth in mice, improves glucose homeostasis, insulin sensitivity and lipid metabolism. The aim of this study was to investigate the therapeutic potential of decreasing liver PTP1B levels in obese and insulin-resistant adult mice.

METHODS

Inducible Ptp1b liver-specific knockout mice were generated using SA-Cre-ER(T2) mice crossed with Ptp1b floxed (Ptp1b(fl/fl)) mice. Mice were fed a high-fat diet (HFD) for 12 weeks to induce obesity and insulin resistance. Tamoxifen was administered in the HFD to induce liver-specific deletion of Ptp1b (SA-Ptp1b(-/-) mice). Body weight, glucose homeostasis, lipid homeostasis, serum adipokines, insulin signalling and endoplasmic reticulum (ER) stress were examined.

RESULTS

Despite no significant change in body weight relative to HFD-fed Ptp1b(fl/fl) control mice, HFD-fed SA-Ptp1b(-/-) mice exhibited a reversal of glucose intolerance as determined by improved glucose and pyruvate tolerance tests, decreased fed and fasting blood glucose and insulin levels, lower HOMA of insulin resistance, circulating leptin, serum and liver triacylglycerols, serum NEFA and decreased HFD-induced ER stress. This was associated with decreased glycogen synthase, eukaryotic translation initiation factor-2α kinase 3, eukaryotic initiation factor 2α and c-Jun NH2-terminal kinase 2 phosphorylation, and decreased expression of Pepck.

CONCLUSIONS/INTERPRETATION

Inducible liver-specific PTP1B knockdown reverses glucose intolerance and improves lipid homeostasis in HFD-fed obese and insulin-resistant adult mice. This suggests that knockdown of liver PTP1B in individuals who are already obese/insulin resistant may have relatively rapid, beneficial therapeutic effects.

Type 1 diabetes structured education: What are the core self-management behaviours?

AIMS

Study aims were to (1) describe and compare the way diabetes structured education courses have evolved in the UK, (2) identify and agree components of course curricula perceived as core across courses and (3) identify and classify self-care behaviours in order to develop a questionnaire assessment tool.

METHODS

Structured education courses were selected through the Type 1 diabetes education network. Curricula from five courses were examined and nine educators from those courses were interviewed. Transcripts were analysed using framework analysis. Fourteen key stakeholders attended a consensus meeting, to identify and classify Type 1 diabetes self-care behaviours.

RESULTS

Eighty-three courses were identified. Components of course curricula perceived as core by all diabetes educators were: carbohydrate counting and insulin dose adjustment, hypoglycaemia management, group work, goal setting and empowerment, confidence and control. The broad areas of self-management behaviour identified at the consensus meeting were carbohydrate counting and awareness, insulin dose adjustment, self-monitoring of blood glucose, managing hypoglycaemia, managing equipment and injection sites; and accessing health care. Specific self-care behaviours within each area were identified.

CONCLUSIONS

Planned future work will develop an updated questionnaire tool to access self-care behaviours. This will enable assessment of the effectiveness of existing structured education programmes at producing desired changes in behaviour. It will also help people with diabetes and their healthcare team identify areas where additional support is needed to initiate or maintain changes in behaviour. Provision of such support may improve glycaemia and reduce diabetes-related complications and severe hypoglycaemia.

The Tayside insulin management course: an effective education programme in type 1 diabetes

AIMS

The Tayside insulin management (TIM) course is an intensive insulin management programme for adults with type 1 diabetes. The aim was to assess its effectiveness.

METHODS

Haemoglobin A1c (HbA1c) and body mass index (BMI) from individuals with type 1 diabetes were collected 3 months before, and 6 and 24 months after the programme. The programme involved a full day of education per week for 4 weeks in a row. Quality of life was assessed using the standardised Audit of Diabetes-Dependent Quality of Life (ADDQoL) questionnaire completed both before and 3 months after the course. Subjects were also asked to complete a pre- and postcourse questionnaire gathering information about aspects of their diabetes management. In addition, individual satisfaction with course content and delivery was recorded.

RESULTS

Participants had a median reduction in haemoglobin A1c (HbA1c) of 4 mmol/mol (0.4%) after 6 months and 5 mmol/mol (0.5%) 2 years after the course (p < 0.001). Mean daily dose of short-acting insulin decreased from 31.5 (1.9) units to 27.3 (1.9, p < 0.001). There was no significant change in BMI. There was an improvement in all 18 domains of the ADDQoL questionnaire. There was a decrease in hypoglycaemia unawareness from 34.3 ± 47.8% of patients to 8.6 ± 28% (p < 0.001), and a decrease in self-reported lipohypertrophy from 27.8% to 11.1% (p = 0.001). There was a significant reduction in the mean number of diabetic ketoacidosis and severe hypoglycaemic episodes. The number of blood glucose checks changed from 2.8 ± 2.1 to 3.2 ± 1.1 (p = 0.058) per day. Participant satisfaction with all aspects of course content and delivery was high.

CONCLUSIONS

TIM is an effective intensive education programme for patients with type 1 diabetes.

Pilot project and evaluation of delivering diabetes work-based education using video conferencing

CONTEXT

Diabetes is a chronic long-term disease with an increasing incidence. There is a need to increase access to effective care and to ensure such care is delivered as locally as possible. The geographical spread of NHS Highland Scotland presents additional challenges to ensuring a skilled workforce given education is normally work-based tuition and assessment. The aim of this pilot project was to deliver teleconferenced diabetes training to healthcare and allied healthcare professionals who provide basic level care for, and management of, people with diabetes and to evaluate this training.

ISSUE

Work-based diabetes education was designed to be delivered by a diabetes educator through videoconferencing or face to face (F2F) for healthcare professionals in peripheral settings in the Scottish Highlands region over two half-days. The education covered theoretical and practical training in diabetes. The evaluation of the project was through post-course questionnaires and assessment instruments to capture views of the content and delivery mode, as well as student performance.

LESSONS LEARNED

Feedback from participants indicated that the educational content was relevant and that the use of videoconferencing (VC) could provide accessibility to training where distance, cost and other issues may make access difficult. Student performance on the assessment instruments did not differ between those who received the training through video conferencing and those who received the training through F2F delivery. Video conferencing can counteract the difficulties of accessing training for clinical peripherally based professionals. Training through VC did not compromise student acquisition of learning outcomes. Feedback indicates that VC can reduce the interactive nature of the learning and teaching experience.

Sexual coercion prior to imprisonment: prevalence, demographic and behavioural correlates

Little is known about experiences of sexual coercion among prisoners prior to incarceration. Prisoner populations are routinely excluded from national surveys of sexual health which also tend to under-represent marginalized groups. We surveyed 2351 randomly selected men and women, aged 18–64 years, in New South Wales and Queensland prisons who participated in a computer-assisted telephone interview. Around 60% of women and 14% of men self-reported having been sexually coerced prior to incarceration, with 60% of these experiences occurring before the age of 16 years. Factors independently associated with a self-reported history of sexual coercion were: homosexual and bisexual identity, being unable to work, separated marital status, higher level of education (among women), having been paid for sex, a past sexually transmissible infection (among men), drug use (among women) and a history of mental health problems. Prior sexual coercion was associated with unwanted sexual contact and physical assault while in prison. The high prevalence of sexual coercion reported by prisoners and its association with a range of factors indicates a need for a greater acknowledgement of the potential consequences of this within the criminal justice system. This could entail providing counselling and support services within the correctional setting.

Facing the future: the effects of the impending financial drought on NHS finances and how UK radiology services can contribute to expected efficiency savings

The recent turmoil within the banking sector has led to the development of the most significant recession since the "great depression" of the 1930s. Although the coalition government has promised to "guarantee that health spending increases in real terms in each year of Parliament", this may still not be enough to meet future needs over the coming years due to increasing demand and cost pressures. The expected mismatch between actual National Health Service (NHS) funding post-2011 and that required to satisfy increasing demand has been estimated by the Department of Health to require efficiency savings representing up to one-fifth of the overall NHS budget. This paper explains the reasons behind the anticipated slowdown in the growth of real NHS funding, and how, as a discipline, radiology can increase the efficiency of the services it provides in anticipation of future financial austerity within the NHS.

Knowledge of sexually transmissible infections: a comparison of prisoners and the general population

The World Health Organization (WHO) has identified a failure to provide education for vulnerable populations such as prisoners as a contributing factor to the epidemic of sexually transmissible infections (STIs). Despite this recognition, little is known about prisoners' level of knowledge of STIs compared with the general population. Using computer-assisted telephone interviews, we compared a representative sample of 2289 Australian prisoners, aged 18–59 years from New South Wales and Queensland prisons with a representative community sample of 3536 participants from these two states. Prisoners had significantly better knowledge than the general community of chlamydia-related questions, while knowledge of herpes (genital and oral) was slightly better in the community sample. Prisoners who were aged over 25 years, not married, female, self-identified as either homosexual or bisexual and reported a history of STIs tended to have better STI knowledge levels. Despite their more disadvantaged backgrounds, prisoners demonstrated relatively good health literacy in relation to STIs. Ongoing education about the transmission risks of STIs for prisoners and the general community is needed.

The value of postoperative/preadjuvant chemotherapy computed tomography in the management of patients with ovarian cancer

OBJECTIVE

The objectives of the study were to compare the operative assessment of residual disease with the postoperative computed tomography (CT) findings in patients with ovarian cancer who underwent primary surgical cytoreduction or interval debulking surgery to residual disease 1 cm or less and to assess the effect of potential prognostic factors on patient survival.

METHODS

Patients scheduled for surgery and with an available postoperative CT were eligible for the study. Images were retrospectively analyzed in consensus by 2 radiologists.A 5-point qualitative scoring system was used to evaluate the CT findings (1 = tumor definitely absent, 2 = tumor probably absent, 3 = tumor possibly present, 4 = tumor probably present, 5 = tumor definitely present).

RESULTS

Between September 2005 and December 2008, 206 consecutive patients were enrolled; 51 were eligible. In 30 cases (59%), the postoperative CT findings correlated with the surgeon's assessment of residual disease. For the univariate analyses, the only significant prognostic factors associated with overall survival were no residual disease versus residual disease of less than 1 cm as assessed by the surgeon (hazard ratio [HR], 3.06; 95%confidence interval [CI], 1.29--7.27; P = 0.011) and no residual disease versus residual disease greater than 1 cm on CT (HR, 2.57; 95% CI, 1.02--6.48; P = 0.045). The interaction of surgical residual disease and stage 3 was significant (HR, 3.40; 95% CI, 1.42--8.16;P = 0.006) in the multivariate Cox model.

CONCLUSIONS

There was only 59% correlation between the surgical assessment and post operative CT findings of residual disease in patients reported to have undergone optimal surgery. Stage and residual disease as assessed by the surgeon were significant prognostic factors for overall survival. The value for postoperative CT may lie in those cases with small-volume residual disease (visible but reported as G1 cm) at surgery.

Visceral abdominal obesity--is there an increased prevalence in men presenting with testicular teratoma?

BACKGROUND

There is evidence to suggest a link between the accumulation of visceral abdominal adipose tissue and an increased incidence of prostate, endometrial, breast, and colonic cancer.

PURPOSE

To investigate whether an increase in ratio of visceral to subcutaneous abdominal adipose tissue is demonstrated in patients with testicular teratoma.

MATERIAL AND METHODS

Following ethical approval, 22 male patients who had undergone staging computed tomography (CT) between 2004 and 2007 for testicular teratoma were identified from our database. Abdominal adipose tissue distribution for these 22 patients was compared with that of 22 control patients, standardized for age, sex, and body mass index. Visceral and subcutaneous adipose tissue volumes were calculated from a single axial CT slice at the level of the umbilicus. A two-sample t test for the difference in volume ratio between the two groups was used. A P value of < 0.05 was considered statistically significant.

RESULTS

There was a statistically significant difference in the mean ratio of visceral to subcutaneous volumes between the teratoma patients and controls (P=0.02). The ratio in teratoma patients was 1.56 times greater than seen in control patients.

CONCLUSION

Patients with testicular teratoma have a relatively greater proportion of abdominal visceral adipose tissue compared with controls. This is concordant with published literature for other malignancies.

A review of the biological and potential therapeutic actions ofHarpagophytum procumbens

Harpagophytum procumbens (Hp), commonly known as Devil's Claw is a perennial plant which thrives in arid conditions. For centuries, it has been used as a traditional treatment for a variety of illnesses, including fevers, skin complaints, arthritis and diseases of the digestive tract as well as an appetite stimulant. Since its introduction to Europe in the early twentieth century, it has become a popular antiinflammatory and analgesic preparation amongst herbalists for supportive or adjuvant treatment of degenerative joint diseases, tendonitis, headache, backache and menstrual pain. The validity of Hp as an effective antiinflammatory and analgesic preparation, particularly in the relief of arthritic symptoms, has been investigated in numerous animal, clinical and in vitro studies. Although some contradictory evidence exists, the majority of animal studies appear to indicate Hp as an effective antiinflammatory and analgesic preparation in the treatment of acute and subacute inflammation. Clinical trials support Hp as a beneficial treatment for the alleviation of pain and improvement of mobility in a variety of musculoskeletal conditions. Analysis of the in vitro and ex vivo studies that currently exist, indicate that Hp has significant effects on numerous proinflammatory markers. However, the exact mechanism(s) by which Hp may reduce inflammation remain to be elucidated.

Extreme cause-specific mortality in a cohort of adult prisoners—1988 to 2002: a data-linkage study

OBJECTIVES

Describe the standardized mortality ratio (SMR) and its trend in adults who have served time in prison.

DESIGN

A retrospective cohort study of 85,203 adults imprisoned in New South Wales (NSW), Australia, between 1 January 1988 and 31 December 2002.

METHODS

We obtained information on deaths by record linkage with the Australian National Death Index (NDI). Mortality rates were estimated using the person-time method. SMRs were calculated using sex, age, and calendar-specific death rates from the NSW population. Time trends in SMRs were assessed using the test for linear trends.

RESULTS

The median overall follow-up of the cohort was 7.7 years. We identified 5137 deaths (4714 men, 423 women) among the cohort of which the vast majority (4834, 94%) occurred following release from custody. All-cause SMR was 3.7 (95% CI: 3.6-3.8) in men and 7.8 (95% CI: 7.1-8.5) in women. SMRs were substantially raised for deaths due to mental and behavioural disorders (men: 13.2, 95% CI: 12.3-14.0; women: 62.8, 95% CI: 52.7-74.9) and drug-related deaths (men: 12.8, 95% CI: 12.2-13.5; women: 50.3, 95% CI: 43.7-57.8). The SMR for death by homicide was 10.2 (95% CI: 8.9-11.7) in men and 26.3 (95% CI: 17.8-39.0) in women. Aboriginal men were 4.8 times, and Aboriginal women 12.6 times, more likely to die than the general NSW population. Over the study period on average all-cause SMR decreased significantly in men (p = 0.003) and women (p = 0.05) largely due to the decline in SMRs for drug-related deaths and suicide.

CONCLUSION

In the largest study so far reported, mortality of male and female offenders was far greater than expected for all major causes, especially deaths caused by drug overdose. Despite some indication of a reduction in excess mortality in recent years, there remains an overwhelming need for enhanced responses to mental health and drug problems for people who have been in prison.

Selected fruits reduce azoxymethane (AOM)-induced aberrant crypt foci (ACF) in Fisher 344 male rats

Phytochemicals contribute to the vibrant colors of fruits and it is suggested that the darker the fruit the higher the antioxidative or anticarcinogenic properties. In this study we investigated the possible effects of blueberries (BLU), blackberries (BLK), plums (PLM), mangoes (MAN), pomegranate juice (POJ), watermelon juice (WMJ) and cranberry juice (CBJ) on azoxymethane (AOM)-induced aberrant crypt foci (ACF) in Fisher 344 male rats. Forty-eight male Fisher 344 rats were randomly assigned to eight groups (n=6). The groups were fed AIN-93G as a control (C) diet, the rats fed fruits received AIN-93G+5% fruits and the groups that were given fruits juices received 20% fruit juice instead of water. The rats received subcutaneous injections of AOM at 16 mg/kg body weight at seventh and eighth weeks of age. At 17th week of age, the rats were killed by CO(2) asphyxiation. Total ACF numbers (mean+/-SEM) in the rats fed CON, BLU, BLK, PLM, MNG, POJ, WMJ and CBJ were 171.67+/-5.6, 11.33+/-2.85, 24.0+/-0.58, 33.67+/-0.89, 28.67+/-1.33, 15.67+/-1.86, 24.33+/-3.92 and 39.0+/-15.31. Total glutathione-S-transferase (GST) activity (mICROmol/mg) in the liver of the rats fed fruits (except BLK) and fruit juices were significantly (p<0.05) higher in the rats fed fruits and fruit juices compared with the control. Our findings suggest that among the fruits and fruit juices, BLU and POJ contributed to significant (P<0.05) reductions in the formation of AOM-induced ACF.

Weight loss and long-term follow-up of severely obese individuals treated with an intense behavioral program

OBJECTIVE

To review weight loss and maintenance for severely obese individuals enrolled in intensive behavioral weight loss program using very-low or low-energy diets.

DESIGN

Chart review of consecutively treated patients between 1995 and 2002 seen at three weight loss centers.

SUBJECTS

One thousand five hundred and thirty one patients with severe obesity (>or=40 kg/m(2)) treated in three cities ('Study Group'). Of these, 1100 completed the 12-week core curriculum ('Completer Group'). Weight loss >or=100 lbs (>45 kg) was seen in 268 patients ('100-Pound Group').

MEASUREMENTS

Charts were reviewed for baseline characteristics, weekly weights, follow-up weights and side effects.

RESULTS

In the Study Group, average weight loss+/-s.e. for 998 women was 23.9+/-0.6 kg (18.5% of initial body weight (IBW)) and for 533 men was 36.0+/-1.0 kg (22.5%) over 30 weeks. For Completers, average weight loss for women was 30.8+/-0.6 kg (23.9%) and for men was 42.6+/-1.1 kg (26.7%) over 39 weeks. In the 100-Pound Group, average weight loss for women was 58.2+/-1.2 kg (41.5%) in 65 weeks and for men was 65.7+/-1.5 kg (37.5%) in 51 weeks. Side effects, assessed in 100 patients losing >45 kg, were mild to moderate in severity. Severe adverse events unrelated to the diet were noted in 5% of patients and during weight loss 1% had elective cholecystectomies. Follow-up weights were available for 86% of Completers at an average of 72 weeks with average maintenance of 23 kg or 59% of weight loss; follow-up weights were available for 94% of the 100-Pound Group at an average of 95 weeks with average maintenance of 41 kg or 65% of weight loss maintained.

CONCLUSIONS

Intensive behavioral treatment with meal replacements is a safe and effective weight-loss strategy for selected severely obese individuals.

Confirmation of CHD7 as a cause of CHARGE association identified by mapping a balanced chromosome translocation in affected monozygotic twins

BACKGROUND

CHARGE syndrome has an estimated prevalence of 1/10,000. Most cases are sporadic which led to hypotheses of a non-genetic aetiology. However, there was also evidence for a genetic cause with reports of multiplex families with presumed autosomal dominant, possible autosomal recessive inheritance and concordant twin pairs. We identified a monozygotic twin pair with CHARGE syndrome and a de novo balanced chromosome rearrangement t(8;13)(q11.2;q22).

METHODS

Fluorescence in situ hybridisation was performed with BAC and PAC probes to characterise the translocation breakpoints. The breakpoint on chromosome 8 was further refined using 10 kb probes we designed and produced using sequence data for clone RP11 33I11, the Primer3 website, and a long range PCR kit.

RESULTS

BAC and PAC probe hybridisation redefined the breakpoints to 8q12.2 and 13q31.1. Probe RP11 33I11 spanned the breakpoint on chromosome 8. Using our 10 kb probes we demonstrated that the chromodomain gene CHD7 was disrupted by the translocation between exons 3 and 8.

DISCUSSION

Identifying that the translocation breakpoint in our patients occurred between exons 3 and 8 of CHD7 suggests that disruption of this gene is the cause of CHARGE syndrome in the twins and independently confirms the role of CHD7 in CHARGE syndrome.

Validation of a test model of induced dysmenorrhea

BACKGROUND

The myometrial hyperactivity and reduced uterine blood flow of primary dysmenorrhea is to a large extent caused by increased vasopressin secretion. A new therapeutic approach for this condition is to develop antagonists of uterine vasopressin V1a receptors. We studied a test model of vasopressin-induced dysmenorrhea in healthy, sterilized women and compared responses against those in dysmenorrheic subjects.

METHODS

Eight women with primary dysmenorrhea and eight sterilized, healthy women participated in recordings of intrauterine pressure and experienced pain on days 1-2 of two menstruations. We tried to identify biochemical markers in plasma of uterine ischemia. Furthermore, the effects of repeated bolus injections of 10 pmol/kg b w of vasopressin or placebo on these parameters were assessed.

RESULTS

The vasopressin injections caused statistically significant increases in the area under the intrauterine pressure curve (AUC) in both healthy volunteers and patients with dysmenorrhea, the overall responses being greater in healthy volunteers. The experienced pain measured by visual analog scale in individual dysmenorrheic subjects tended to show higher maximal post-dose scores for the vasopressin injections than for placebo. Maximum visual analog scale scores and maximum AUCs in individual subjects tended to be related. Mean creatine kinase MB levels were higher in women with dysmenorrhea than in healthy subjects both before and after vasopressin administration, the converse being observed for C-reactive protein levels.

CONCLUSIONS

The present model appears to be useful for evaluating new drugs for the treatment of primary dysmenorrhea.