Protein supplementation changes gut microbial diversity and derived metabolites in subjects with type 2 diabetes

High-protein diets are promoted for individuals with type 2 diabetes (T2D). However, effects of dietary protein interventions on (gut-derived) metabolites in T2D remains understudied. We therefore performed a multi-center, randomized-controlled, isocaloric protein intervention with 151 participants following either 12-week high-protein (HP; 30Energy %, N = 78) vs. low-protein (LP; 10 Energy%, N = 73) diet. Primary objectives were dietary effects on glycemic control which were determined via glycemic excursions, continuous glucose monitors and HbA1c. Secondary objectives were impact of diet on gut microbiota composition and -derived metabolites which were determined by shotgun-metagenomics and mass spectrometry. Analyses were performed using delta changes adjusting for center, baseline, and kidney function when appropriate. This study found that a short-term 12-week isocaloric protein modulation does not affect glycemic parameters or weight in metformin-treated T2D. However, the HP diet slightly worsened kidney function, increased alpha-diversity, and production of potentially harmful microbiota-dependent metabolites, which may affect host metabolism upon prolonged exposure.

Effects of the COVID-19 pandemic and lockdown on the mental and physical health of adults with Prader-Willi syndrome

Background

Prader-Willi syndrome (PWS) is a neurodevelopmental disorder with hypothalamic dysfunction leading to obesity and behavioral disabilities, including eating disorders (EDs). We evaluated the effects of the COVID-19 infection and lockdown on mental and physical health in PWS. At the end of April, 85 adults with PWS completed a self-administered questionnaire, including lockdown conditions, physical activity (PA), ED, and medical and behavioral outcomes. Body weight was measured at home and self-reported.

Results

Patients (52.9% women, 44.8% disomic) were assessed, with a mean age of 28.05 ± 8.73 years and body mass index (BMI) of 36.76 ± 10.74 kg/m². Seventy percent lived in the Paris region (France) and were confined with their parents. The mean weight change was 0.96 ± 3.28 kg. We compared patients showing weight loss (n = 39, − 3.30 ± 2.93 kg) to patients showing weight gain (n = 22, + 2.35 ± 1.54 kg): the BMI was lower (34.60 ± 9.18 versus 40.45 ± 9.45 kg/m², p = 0.02), PA increased (25.6% versus 4.5%, p = 0.04), and EDs improved (51.3% versus 13.6%, p = 0.005). Behavioral disorders increased for 12.9% of the cohort. Three individuals (3.5%) were diagnosed with non-severe COVID-19.

Conclusion

Lockdown during the COVID-19 pandemic was associated with positive effects for most French adults with PWS, with weight loss probably associated with a more favourable environment during this period. We observed no severe forms of COVID-19.

COVID-19 and its Severity in Bariatric Surgery-Operated Patients

OBJECTIVE

Obesity is a major risk factor for severe forms of coronavirus disease (COVID-19), but little is known about the post-bariatric surgery (BS) setting. The prevalence of likely COVID-19 and its risk factors in patients followed up after BS was assessed.

METHODS

A total of 738 patients who underwent BS and were followed up at a university medical center were surveyed. A retrospective comparison of characteristics at baseline, 1 year after BS, and at the time of lockdown was performed between patients with COVID-19-likely events (CL) based on a combination of reported symptoms and those for whom COVID-19 was unlikely.

RESULTS

CL occurred in 62 (8.4%) patients, among whom 4 (6.4%) had a severe form requiring hospitalization and 1 (1.6%) died. The CL group had a higher proportion of persistent type 2 diabetes (T2D) at last follow-up (36.2% vs. 20.3%, P = 0.01). BMI at the time of lockdown was lower in the CL group (30.2 ± 5.1 vs. 32.8 ± 6.5 kg/m² ; P < 0.01) with higher percent weight loss since BS in the CL group. Severe forms of COVID-19 requiring hospitalization were associated with persistent T2D at the last follow-up visit.

CONCLUSIONS

In BS patients, CL were associated with persistent T2D and lower BMI.

P4592Total arterial revascularization in severe coronary artery disease: a 25-years single-center experience

Objective

To evaluate very long-term survival of Total Arterial Revascularization (TAR) in patients with severe coronary artery disease (CAD) undergoing Coronary Artery Bypass Grafting (CABG).

Methods

Between January 1992 and December 2017, 13798 patients aged 70 years or less underwent primary isolated CABG with at least two grafts in our department. Patients receiving TAR were matched by propensity-score analysis to the rest of the population. All pre- and peri-operative data were collected prospectively in our institutional database. Long-term survival was assessed using provincial vital statistics data. The primary outcome was very-long time survival, secondary outcomes were operative mortality and early complications.

Results

Propensity-score matching identified 602 pairs with similar preoperative characteristics. In the matched control group, 65.4% and 30.9% of patients received 1 and 2 arterial grafts, respectively, whereas 3 or more arterial grafts were used in 3.6%. Less distal anastomoses (2.57±0.77 vs 3.39±0.97, p<0.0001) were performed in TAR patients, who therefore had a shorter cross-clamping time (44.2±14.7 vs 52.9±19.6, p<0.0001). Operative mortality was similar (0.5% vs 1.0%, p=0.51) and there was no difference in the rate of mediastinitis (2.5% vs 0.8%, p=0.28)for the TAR and matched control groups, respectively. TAR patients were less likely to receive blood transfusions (34.9% vs 40.7%, p=0.04). The average follow-up was 13.4±6.7 years. Cox-adjusted survival was significantly better in patients receiving TAR compared to the matched population, up to 25 years postoperatively (HR 0.87 [0.86–0.88], p<0.0001, Figure 1).

Figure 1

Conclusion

Total arterial revascularization is not associated with increased perioperative risk of complications and provides long-term survival benefits up to 25 years postoperatively.

Localization of multiple neurotransmitters in surgically derived specimens of human atrial ganglia

Dysfunction of the intrinsic cardiac nervous system is implicated in the genesis of atrial and ventricular arrhythmias. While this system has been studied extensively in animal models, far less is known about the intrinsic cardiac nervous system of humans. This study was initiated to anatomically identify neurotransmitters associated with the right atrial ganglionated plexus (RAGP) of the human heart. Biopsies of epicardial fat containing a portion of the RAGP were collected from eight patients during cardiothoracic surgery and processed for immunofluorescent detection of specific neuronal markers. Colocalization of markers was evaluated by confocal microscopy. Most intrinsic cardiac neuronal somata displayed immunoreactivity for the cholinergic marker choline acetyltransferase and the nitrergic marker neuronal nitric oxide synthase. A subpopulation of intrinsic cardiac neurons also stained for noradrenergic markers. While most intrinsic cardiac neurons received cholinergic innervation evident as punctate immunostaining for the high affinity choline transporter, some lacked cholinergic inputs. Moreover, peptidergic, nitrergic, and noradrenergic nerves provided substantial innervation of intrinsic cardiac ganglia. These findings demonstrate that the human RAGP has a complex neurochemical anatomy, which includes the presence of a dual cholinergic/nitrergic phenotype for most of its neurons, the presence of noradrenergic markers in a subpopulation of neurons, and innervation by a host of neurochemically distinct nerves. The putative role of multiple neurotransmitters in controlling intrinsic cardiac neurons and mediating efferent signaling to the heart indicates the possibility of novel therapeutic targets for arrhythmia prevention.

Phase-matched excitation of whispering-gallery-mode resonances by a fiber taper

We show that high-Q whispering-gallery modes in fused-silica microspheres can be efficiently excited by an optical fiber taper. By adjusting the taper diameter to match the ropagation constant of the mode in the taper with that of the resonant mode of interest, one can couple more than 90% of the light into the sphere. This represents a significant improvement in excitation efficiency compared with other methods and is, we believe, the most efficient excitation of a high- Q microcavity resonance by a monomode optical fiber yet demonstrated.

Molecular cloning and immunolocalization of two variants of the major basic nuclear protein (HCc) from the histone-less eukaryote Crypthecodinium cohnii (Pyrrhophyta)

Two clones that encode variants (HCc1 and HCc2) of the major basic nuclear protein of the dinoflagellate Crypthecodinium cohnii, were identified by immunoscreening of a cDNA expression library. The first clone carries a full-length cDNA with an open reading frame (HCc1) encoding 113 amino acids. The cDNA from the second clone lacks some of the 5' end, and the coding sequence is only 102 residues. The two proteins display 77% sequence similarity and their NH2-ends are homologous to the NH2-peptide of the HCc protein determined by P. Rizzo. The amino acid composition, which confirms the basic nature of lysine-rich HCc proteins, differs markedly from other known DNA-binding proteins such as histones, HMGs or prokaryotic histone-like proteins. No convincing homology was found with other proteins. HCc antigens were localized on C. cohnii by immunofluorescence, and by electron microscopy (EM) with immunogold labelling. HCc proteins are mainly detected at the periphery of the permanently condensed chromosomes, where active chromatin is located, as well as in the nucleolar organizing region (NOR). This suggests that these basic, non-histone proteins, with a moderate affinity for DNA, are involved at some level in the regulation of gene expression.

Basic nuclear proteins of the histone-less eukaryote Crypthecodinium cohnii (Pyrrhophyta): two-dimensional electrophoresis and DNA-binding properties

Unlike typical eukaryotes, the Dinoflagellate Crypthecodinium cohnii does not contain histones but six major basic, low molecular weight nuclear proteins which represent only 10% of the DNA mass and differ from histones in their electrophoretic and DNA-binding properties. These proteins are resolved in two-dimensional electrophoresis (AUT-PAGE x SDS-PAGE). Three proteins with an apparent molecular mass of 16, 16.5 and 17 kDa (p16, p16.5 and p17) are present in addition to the major 14 kDa basic nuclear component (HCc). HCc itself is resolved in three proteins (alpha, beta and gamma). When the proteins are not reduced with 2-mercaptoethanol before 2D-PAGE, the migration of HCc alpha, beta and gamma is modified in a way which suggests the formation of both inter- and intramolecular disulfide bridges and thus, the presence of at least two cysteines. The amino-acid analysis of HCc proteins resolved in 2D gels confirms that they are lysine-rich. HCc alpha, beta and gamma as well as p16, p16.5 and p17 are removed from isolated chromatin with 0.6 M NaCl, indicating that their affinity for DNA in vivo is lower than that of core histones. Furthermore, in vitro, they bind more tightly to single-stranded than to double-stranded DNA.