Impaired skeletal muscle mitochondrial function in morbidly obese patients is normalized one year after bariatric surgery

BackgroundObesity and type 2 diabetes are associated with impaired skeletal muscle mitochondrial metabolism. As an intrinsic characteristic of an individual, skeletal muscle mitochondrial dysfunction could be a risk factor for weight gain and obesity-associated co-morbidities, such as type 2 diabetes. On the other hand, impaired skeletal muscle metabolism could be a consequence of obesity. We hypothesize that marked weight loss after bariatric surgery recovers skeletal muscle mitochondrial function.MethodsSkeletal muscle mitochondrial function as assessed by high-resolution respirometry was measured in 8 morbidly obese patients (body mass index [BMI], 41.3±4.7 kg/m²; body fat, 48.3%±5.2%) before and 1 year after bariatric surgery (mean weight loss: 35.0±8.6 kg). The results were compared with a lean (BMI 22.8±1.1 kg/m²; body fat, 15.6%±4.7%) and obese (BMI 33.5±4.2 kg/m²; body fat, 34.1%±6.3%) control group.ResultsBefore surgery, adenosine diphosphate (ADP)-stimulated (state 3) respiration on glutamate/succinate was decreased compared with lean patients (9.5±2.4 versus 15.6±4.4 O₂ flux/mtDNA; P<.05). One year after surgery, mitochondrial function was comparable to that of lean controls (after weight loss, 12.3±5.5; lean, 15.6±4.4 O₂ flux/mtDNA). In addition, we observed an increased state 3 respiration on a lipid substrate after weight loss (10.0±3.2 versus 14.0±6.6 O₂ flux/mtDNA; P< .05).ConclusionWe conclude that impaired skeletal muscle mitochondrial function is a consequence of obesity that recovers after marked weight loss.     

The experimental design of postmortem studies: the effect size and statistical power

Purpose

The aim is of this study was to show the poor statistical power of postmortem studies. Further, this study aimed to find an estimate of the effect size for postmortem studies in order to show the importance of this parameter. This can be an aid in performing power analysis to determine a minimal sample size.

Methods

GPower was used to perform calculations on sample size, effect size, and statistical power. The minimal significance (α) and statistical power (1 ? β) were set at 0.05 and 0.80 respectively. Calculations were performed for two groups (Student’s t-distribution) and multiple groups (one-way ANOVA; F-distribution).

Results

In this study, an average effect size of 0.46 was found (n = 22; SD = 0.30). Using this value to calculate the statistical power of another group of postmortem studies (n = 5) revealed that the average statistical power of these studies was poor (1 ? β < 0.80).

Conclusion

The probability of a type-II error in postmortem studies is considerable. In order to enhance statistical power of postmortem studies, power analysis should be performed in which the effect size found in this study can be used as a guideline.

     

The framing of alcohol in (non-)sponsored movies: A comparative content analysis of alcohol advertising and portrayals in sponsored and non-sponsored Dutch movies

Aims: Alcohol advertising, in the form of product placement, has been shown to influence the viewer’s alcohol consumption. However, it is not just the portrayal itself that affects behavioural outcomes; the particular message that is conveyed in an alcohol portrayal may actually influence consumer behaviour in a manner known as “framing”. Therefore, the prevalence and framing of alcohol portrayals in movies was investigated by focussing on product placement strategies, several portrayal characteristics and compliance with relevant guidelines/laws. Furthermore, a comparison is made between movies sponsored by an alcohol brand and non-sponsored movies.

Methods: Sixteen Dutch movies (of which 50% were sponsored) underwent content analysis using a four-category, 21-item coding scheme. Alcohol was present in every movie and a total of 937 alcohol portrayals were analysed.

Findings: The results show that the alcohol portrayals were predominantly positive. In the sponsored movies, more liquor was consumed and alcohol portrayals had a lower plot connection.

Conclusions: In general, the differences between alcohol portrayals in movies sponsored by an alcohol brand compared with non-sponsored movies were rather small. However, the portrayals sometimes offend the legislation regarding regular alcohol commercials, and given the effects of alcohol portrayals on young viewers, this needs attention.     

Clinical- and surgery-specific risk factors for post-operative sepsis: a systematic review and meta-analysis of over 30 million patients

Surgery Today - Post-operative sepsis is a severe complication of surgery, which often worsens the clinical outcomes. While several risk factors have been identified, the importance of others...     

A More Than 20% Increase in Deceased-Donor Organ Procurement and Transplantation Activity After the Use of Donation After Circulatory Death

Background

Organ procurement and transplant activity from controlled donation after circulatory death (DCD) was evaluated over an 11-year period to determine whether this program influenced the transplant and donation after brain death (DBD) activities.

Material and Methods

Deceased donor (DD) procurement and transplant data were prospectively collected in a local database for retrospective review.

Results

There was an increasing trend in the potential and actual DCD numbers over time. DCD accounted for 21.9% of the DD pool over 11 years, representing 23.7% and 24.2% of the DD kidney and liver pool, respectively. The DBD retrieval and transplant activity increased during the same time period. Mean conversion rate turning potential into effective DCD donors was 47.3%. Mean DCD donor age was 54.6 years (range, 3–83). Donors ≥60 years old made up 44.1% of the DCD pool. Among referred donors, reasons for nondonation were medical contraindications (33.7%) and family refusals (19%). Mean organ yield per DCD donor was 2.3 organs. Mean total procurement warm ischemia time was 19.5 minutes (range, 6–39). In 2012, 17 DCD and 37 DBD procurements were performed in the Liege region, which has slightly >1 million inhabitants.

Conclusions

This DCD program implementation enlarged the DD pool and did not compromise the development of DBD programs. The potential DCD pool might be underused and seems to be a valuable organ donor source.     

Effects of caffeinated vs. non-caffeinated alcoholic beverage on next-day hangover incidence and severity,perceived sleep quality,and alertness

Aims

Beliefs about the effects of mixing caffeine and alcohol on hangover or sleep may play a role in motivation to consume these mixtures; therefore, information is needed about actual effects. We investigated whether intoxication with caffeinated vs. non-caffeinated beer differentially affected perceived sleep quality, sleepiness, and hangover incidence and severity the next morning.

Methods

University students (89%) and recent graduate drinkers were randomized to receive: (1) beer with the equivalent of 69 mg caffeine/12 oz glass of regular beer (n = 28) or (2) beer without caffeine (n = 36), in sufficient quantity to attain a BrAC of 0.12 g%. After an 8-h supervised sleep period, participants completed measures of hangover, sleep quality, sleep latency and time asleep, and sleepiness.

Results

While caffeinated beer improved perceived sleep quality, effect sizes were greater for morning alertness than for quality while sleeping, with no effect on sleep latency or total sleep time. No effects were seen on hangover incidence or severity.

Conclusions

Mixing caffeine and alcohol does not significantly impair amount of sleep or sleep latency, hangover, or sleepiness the morning after drinking to intoxication in this population.     

A graphene-based hybrid material with quantum bits prepared by the double Langmuir–Schaefer method

The scalability and stability of molecular qubits deposited on surfaces is a crucial step for incorporating them into upcoming electronic devices. Herein, we report on the preparation and characterisation of a molecular quantum bit, copper(ii)dibenzoylmethane [Cu(dbm)₂], deposited by a modified Langmuir–Schaefer (LS) technique onto a graphene-based substrate. A double LS deposition was used for the preparation of a few-layer-graphene (FLG) on a Si/SiO₂ substrate with subsequent deposition of the molecules. Magnetic properties were probed by high-frequency electron spin resonance (HF-ESR) spectroscopy and found maintained after deposition. Additional spectroscopic and imaging techniques, such as Raman spectroscopy (RS), X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM) were performed to characterise the deposited sample. Our approach demonstrated the possibility to utilise a controlled wet-chemistry protocol to prepare an array of potential quantum bits on a disordered graphene-based substrate. The deployed spectroscopic techniques showed unambiguously the robustness of our studied system with a potential to fabricate large-scale, intact, and stable quantum bits.

Graphene-based hybrid material with array of copper(ii)-based quantum bits was prepared by a wet-chemistry protocol and characterised by HF-ESR, XPS, Raman, and AFM.