The Diabetes Excess Weight Loss (DEWL) Trial: a randomised controlled trial of high-protein versus high-carbohydrate diets over 2 years in type 2 diabetes

Aims/hypothesis  

To compare the effectiveness of low-fat high-protein and low-fat high-carbohydrate dietary advice on weight loss, using group-based interventions, among overweight people with type 2 diabetes.     

Timing of climate variability and grassland productivity

Future climates are forecast to include greater precipitation variability and more frequent heat waves, but the degree to which the timing of climate variability impacts ecosystems is uncertain. In a temperate, humid grassland, we examined the seasonal impacts of climate variability on 27 y of grass productivity. Drought and high-intensity precipitation reduced grass productivity only during a 110-d period, whereas high temperatures reduced productivity only during 25 d in July. The effects of drought and heat waves declined over the season and had no detectable impact on grass productivity in August. If these patterns are general across ecosystems, predictions of ecosystem response to climate change will have to account not only for the magnitude of climate variability but also for its timing.     

Methanobrevibacter smithii Is the Predominant Methanogen in Patients with Constipation-Predominant IBS and Methane on Breath

Purpose

Among irritable bowel syndrome (IBS) patients, breath methane producers overwhelmingly have constipation predominance (C-IBS). Although the most common methanogen in humans is Methanobrevibacter smithii, incidence and type of methanogenic bacteria in C-IBS patients are unknown.

Methods

By use of a questionnaire and lactulose breath testing, subjects with Rome II C-IBS and methane (>3?ppm) were selected (n?=?9). The control group included subjects with IBS who had no breath methane (n?=?10). Presence of bacterial DNA was assessed in a stool sample of each subject by quantitative-PCR using universal 16S rDNA primer. M. smithii was quantified by use of a specific rpoB gene primer.

Results

M. smithii was detected in both methane and non-methane subjects. However, counts and relative proportion of M. smithii were significantly higher for methane-positive than for methane-negative subjects (1.8?×?10⁷?±?3.0?×?10⁷ vs 3.2?×?10⁵?±?7.6?×?10⁵?copies/g wet stool, P?<?0.001; and 7.1?±?6.3?% vs 0.24?±?0.47?%, P?=?0.02 respectively). The minimum threshold of M. smithii resulting in positive lactulose breath testing for methane was 4.2?×?10⁵?copies/g wet stool or 1.2?% of total stool bacteria. Finally, area-under-curve for breath methane correlated significantly with both absolute quantity and percentage of M. smithii in stool (R?=?0.76; P?<?0.001 and R?=?0.77; P?<?0.001 respectively).

Conclusions

M. smithii is the predominant methanogen in C-IBS patients with methane on breath testing. The number and proportion of M. smithii in stool correlate well with amount of breath methane.     

Response to catecholamine stimulation of polymorphisms of the Beta-1 and Beta-2 adrenergic receptors

Previous studies have demonstrated that β-adrenergic receptor polymorphisms affect outcomes in patients with heart failure or after an acute coronary syndrome. Whether β-adrenergic polymorphisms influence catecholamine responses in patients with cardiovascular disease is not known. Cardiovascular responses to the β1-receptor agonist dobutamine and the β2-receptor agonist terbutaline were studied using gated blood pool scintigraphy in 21 patients on long-term β-blocker therapy. Heart rate (HR), stroke volume (SV), and cardiac output (CO) increased, and end-systolic volume decreased with dobutamine and terbutaline. Changes in HR and CO with dobutamine were higher for those with ≥1 β1 Arg389 allele than those homozygous for the Gly389 allele (change in HR 15 vs 1 beat/min, p = 0.02; change in CO 2.4 vs 1.0 L/min, p = 0.02). Increases in HR, CO, and SV with terbutaline were greater for those homozygous for the β2 Glu27 allele than those with ≥1 Gln27 allele (change in HR 13.7 vs 4.8 beats/min, p = 0.048; change in CO 3.1 vs 1.6 L/min, p = 0.034; change in SV 28.3 vs 14.8 ml, p = 0.045). Changes in CO and volume with terbutaline were greater in those with an ejection fraction <40% than in those with an ejection fraction ≥40%. In conclusion, β-receptor gene variants significantly influence inotropic and chronotropic responses to β-agonist exposure in patients on β-blocker therapy.     

Revisional Bariatric Surgery for Unsuccessful Weight Loss and Complications

Background

There are growing numbers of patients who require revisional bariatric surgery due to the undesirable results of their primary procedures. The aim of this study was to review our experience with bariatric patients undergoing revisional surgery.

Methods

We conducted a retrospective analysis to review the indications for revisional bariatric procedures and assess their postoperative outcomes.

Results

From 04/04 to 01/11, 2,918 patients underwent bariatric surgery at our institution. A total of 154 patients (5.3 %) of these cases were coded as revisional procedures. The mean age at revision was 49.1?±?11.3 and the mean BMI was 44.0?±?13.7 kg/m². Revisional surgery was performed laparoscopically in 121 patients (78.6 %). Laparoscopic revisions had less blood loss, shorter length of hospital stay, and fewer complications compared to open revisions. Two groups (A and B) were defined by the indication for revision: patients with unsuccessful weight loss (group A, n?=?106) and patients with complications of their primary procedures (group B, n?=?48). In group A, 74.5 % of the patients were revised to a bypass procedure and 25.5 % to a restrictive procedure. Mean excess weight loss was 53.7?±?29.3 % after revision of primary restrictive procedures and 37.6?±?35.1 % after revision of bypass procedures at >1-year follow-up (p?<?0.05). In group B, the complications prompting revision were effectively treated by revisional surgery.

Conclusions

Revisional bariatric surgery effectively treated the undesirable results from primary bariatric surgery. Laparoscopic revisional surgery can be performed after both failed open and laparoscopic bariatric procedures without a prohibitive complication rate. Carefully selected patients undergoing revision for weight regain have satisfactory additional weight loss.