Loneliness,Social Integration and Consumption of Sugar-Containing Beverages: Testing the Social Baseline Theory

Objective

Social Baseline Theory (SBT) proposes that close relationships aid in metabolic resource management and that individuals without significant relationships may experience more demands on their own neural metabolic resources on a daily basis when solving problems, remaining vigilant against potential threats and regulating emotional responses. This study tests a hypothesised consequence derived from SBT: relative social isolation leads to increased levels of sugar intake.

Methods

Based on cross-sectional, self-reported data from the Norwegian Mother and Child Cohort Study (N = 90 084), information on social integration and the consumption of both sugar-sweetened and artificially sweetened sodas and juices was obtained from a large number of women in early pregnancy. Multiple regression analyses were conducted to assess whether loneliness, marital status, relationship satisfaction, advice from others than partner, and cohesion at work is associated with consumption of sodas and juices.

Results

Perceived loneliness was associated with elevated intake of all sugary beverages, while relationship satisfaction was negatively associated with all sugary beverages. Being married or cohabitating, having supportive friends, and having a sense of togetherness at work were associated with lower intake of two out of three sugar-containing beverages. These associations were significant, even after controlling for factors such as body mass index, weight related self-image, depression, physical activity, educational level, age and income. In comparison, a statistically significant relationship emerged between relationship satisfaction and artificially sweetened cola. No other predictor variables were significantly associated with any type of artificially sweetened beverage.

Conclusions

This study indicates that loneliness and social integration influence the level of consumption of sugary beverages. The results support the hypothesis derived from the Social Baseline Theory that relative social isolation leads to increased levels of sugar intake.     

Cytotoxic activity of 6-alkynyl- and 6-alkenylpurines

6-Alkynyl- and 6-alkenylpurines have been screened for cytotoxic activity against a human chronic myelogenous leukemia cell line; K-562 cells using a [(3)H]-thymidine incorporation assay. Most alkynes displayed cytotoxicity comparable to, or better than, the known anticancer drugs 6-mercaptopurine and fludarabine. The 6-alkenylpurines, which are promising plant growth stimulators and 15-lipoxygenase inhibitors, exhibited only low toxicity.     

Species tree inference in a recent radiation of orioles (Genus Icterus): multiple markers and methods reveal cytonuclear discordance in the northern oriole group

Recent computational advances provide novel opportunities to infer species trees based on multiple independent loci. Thus, single gene trees no longer need suffice as proxies for species phylogenies. Several methods have been developed to deal with the challenges posed by incomplete and stochastic lineage sorting. In this study, we employed four Bayesian methods to infer the phylogeny of a clade of 11 recently diverged oriole species within the genus Icterus. We obtained well-resolved and mostly congruent phylogenies using a set of seven unlinked nuclear intron loci and sampling multiple individuals per species. Most notably, Bayesian concordance analysis generally agreed well with concatenation; the two methods agreed fully on eight of nine nodes. The coalescent-based method ^∗BEAST further supported six of these eight nodes. The fourth method used, BEST, failed to converge despite exhaustive efforts to optimize the tree search. Overall, the results obtained by new species tree methods and concatenation generally corroborate our findings from previous analyses and data sets. However, we found striking disagreement between mitochondrial and nuclear DNA involving relationships within the northern oriole group. Our results highlight the danger of reliance on mtDNA alone for phylogenetic inference. We demonstrate that in spite of low variability and incomplete lineage sorting, multiple nuclear loci can produce largely congruent phylogenies based on multiple species tree methods, even for very closely-related species.     

Depletion of murine intestinal microbiota: effects on gut mucosa and epithelial gene expression

Background

Inappropriate cross talk between mammals and their gut microbiota may trigger intestinal inflammation and drive extra-intestinal immune-mediated diseases. Epithelial cells constitute the interface between gut microbiota and host tissue, and may regulate host responses to commensal enteric bacteria. Gnotobiotic animals represent a powerful approach to study bacterial-host interaction but are not readily accessible to the wide scientific community. We aimed at refining a protocol that in a robust manner would deplete the cultivable intestinal microbiota of conventionally raised mice and that would prove to have significant biologic validity.

Methodology/Principal Findings

Previously published protocols for depleting mice of their intestinal microbiota by administering broad-spectrum antibiotics in drinking water were difficult to reproduce. We show that twice daily delivery of antibiotics by gavage depleted mice of their cultivable fecal microbiota and reduced the fecal bacterial DNA load by 400 fold while ensuring the animals'' health. Mice subjected to the protocol for 17 days displayed enlarged ceca, reduced Peyer''s patches and small spleens. Antibiotic treatment significantly reduced the expression of antimicrobial factors to a level similar to that of germ-free mice and altered the expression of 517 genes in total in the colonic epithelium. Genes involved in cell cycle were significantly altered concomitant with reduced epithelial proliferative activity in situ assessed by Ki-67 expression, suggesting that commensal microbiota drives cellular proliferation in colonic epithelium.

Conclusion

We present a robust protocol for depleting conventionally raised mice of their cultivatable intestinal microbiota with antibiotics by gavage and show that the biological effect of this depletion phenocopies physiological characteristics of germ-free mice.     

Randomised controlled trial of smoking cessation intervention after admission for coronary heart disease

Objective To determine whether a nurse led smoking cessation intervention affects smoking cessation rates in patients admitted for coronary heart disease.Design Randomised controlled trial.Setting Cardiac ward of a general hospital, Norway.Participants 240 smokers aged under 76 years admitted for myocardial infarction, unstable angina, or cardiac bypass surgery. 118 were randomly assigned to the intervention and 122 to usual care (control group).Intervention The intervention was based on a booklet and focused on fear arousal and prevention of relapses. The intervention was delivered by cardiac nurses without special training. The intervention was initiated in hospital, and the participants were contacted regularly for at least five months.Main outcome measure Smoking cessation rates at 12 months determined by self report and biochemical verification.Results 12 months after admission to hospital, 57% (n = 57/100) of patients in the intervention group and 37% (n = 44/118) in the control group had quit smoking (absolute risk reduction 20%, 95% confidence interval 6% to 33%). The number needed to treat to get one additional person who would quit was 5 (95% confidence interval, 3 to 16). Assuming all dropouts relapsed at 12 months, the smoking cessation rates were 50% in the intervention group and 37% in the control group (absolute risk reduction 13%, 0% to 26%).Conclusion A smoking cessation programme delivered by cardiac nurses without special training, significantly reduced smoking rates in patients 12 months after admission to hospital for coronary heart disease.     

Loss of heterozygosity at the FLCN locus in early renal cystic lesions in dogs with renal cystadenocarcinoma and nodular dermatofibrosis

Small, macroscopically visible cysts on the surface of the kidneys were observed in eight 6–8-week-old puppies diagnosed with renal cystadenocarcinoma and nodular dermatofibrosis (RCND). Histologic examination of the renal cortices in these puppies reveals numerous small cystic tubular changes. Hyperplastic change of the epithelial lining of cysts is frequently observed. By laser-capture microdissection we have sampled epithelial cells from such early renal cystic lesions in eight paternal half-sibs diagnosed with RCND. DNA was obtained from the laser-captured material, and all coding exons of the germline-mutated FLCN gene were sequenced to detect putative second hits. Samples from 31 independent hyperplastic epithelial cell sections of tubular microcysts of the RCND siblings were examined as well as normal control samples of the tissue sections. Loss of heterozygosity was detected in 35% of the transformed samples. The frequently observed loss of heterozygosity at the FLCN locus in atypical epithelial cells lining the cysts suggests that loss of heterozygosity/function of the FLCN gene may contribute to neoplastic transformation of renal epithelial cells at a very early age of RCND-affected dogs. The transformed renal epithelial cells seem to grow slowly in young puppies, which indicates that other mutational events are required for the development of tumors in adult dogs.     

The importance of plant relatedness for host utilization among phytophagous insects

Current methods for measuring similarity among phytophagous insect communities fail to consider the phylogenetic relationship between host plants. We analysed this relation based on 3580 host observations of 1174 beetle species associated with 100 species of angiosperms in two different forest types in Panama. We quantified the significance of genetic distance as well as taxonomic rank among angiosperms in relation to species overlap in beetle assemblages. A logarithmic model describing the decrease in beetle species similarity between host-plant species of increasing phylogenetic distance explains 35% of the variation. Applied to taxonomic rank categories the results imply that except for the ancient branching of monocots from dicots, only adaptive radiations of plants on the family and genus level are important for host utilization among phytophagous beetles. These findings enable improvements in estimating host specificity and species richness through correction for phylogenetic relatedness between hosts and consideration of the host-specific fauna associated with monocots.     

Do hyraxes benefit from human presence in Serengeti?

Understanding the factors affecting a species’ population size is crucial for conservation initiatives. Hyraxes are small, gregarious animals, predominantly found on kopjes (rock outcrops) and thus form metapopulation communities. In Tanzania, two species of hyraxes inhabit Serengeti National Park, the rock hyrax Procavia capensis johnstoni and bush hyrax Heterohyrax brucei. This study focuses on the factors that affect hyrax population size, including factors such as human presence, habitat type, kopje size and kopje height. We found that larger and taller kopjes tended to have more hyraxes than smaller ones, while kopjes in wooded grassland had more hyraxes than kopjes in grassland. Human presence often affects species negatively, but in the case of hyraxes, we found that kopjes with human presence had larger populations than kopjes without humans. We discuss possible explanations for this and suggest that human presence is related to fewer predators and higher food availability.     

Proteogenomics approaches for studying cancer biology and their potential in the identification of acute myeloid leukemia biomarkers

Introduction: Mass spectrometry (MS)-based proteomics has become an indispensable tool for the characterization of the proteome and its post-translational modifications (PTM). In addition to standard protein sequence databases, proteogenomics strategies search the spectral data against the theoretical spectra obtained from customized protein sequence databases. Up to date, there are no published proteogenomics studies on acute myeloid leukemia (AML) samples.

Areas covered: Proteogenomics involves the understanding of genomic and proteomic data. The intersection of both datatypes requires advanced bioinformatics skills. A standard proteogenomics workflow that could be used for the study of AML samples is described. The generation of customized protein sequence databases as well as bioinformatics tools and pipelines commonly used in proteogenomics are discussed in detail.

Expert commentary: Drawing on evidence from recent cancer proteogenomics studies and taking into account the public availability of AML genomic data, the interpretation of present and future MS-based AML proteomic data using AML-specific protein sequence databases could discover new biological mechanisms and targets in AML. However, proteogenomics workflows including bioinformatics guidelines can be challenging for the wide AML research community. It is expected that further automation and simplification of the bioinformatics procedures might attract AML investigators to adopt the proteogenomics strategy.