Gastrointestinal factors regulating lipid droplet formation in the intestine

Cytoplasmic lipid droplets (CLD) are considered as neutral lipid reservoirs, which protect cells from lipotoxicity. It became clear that these fascinating dynamic organelles play a role not only in energy storage and metabolism, but also in cellular lipid and protein handling, inter-organelle communication, and signaling among diverse functions. Their dysregulation is associated with multiple disorders, including obesity, liver steatosis and cardiovascular diseases. The central aim of this review is to highlight the link between intra-enterocyte CLD dynamics and the formation of chylomicrons, the main intestinal dietary lipid vehicle, after overviewing the morphology, molecular composition, biogenesis and functions of CLD.

Erratum: (1) Pediatric Obesity and Cardiometabolic Disorders: Risk Factors and Biomarkers

[This corrects the article on p. 6 in vol. 28, PMID: 28439216.].

Revealing the Topology of Quasicrystals with a Diffraction Experiment

Topological properties of crystals and quasicrystals is a subject of recent and growing interest. This Letter reports an experiment where, for certain quasicrystals, these properties can be directly retrieved from diffraction. We directly observe, using an interferometric approach, all of the topological invariants of finite-length Fibonacci chains in their diffraction pattern. We also quantitatively demonstrate the stability of these topological invariants with respect to structural disorder.

Incidence and Effect of Thromboembolic Events in Radical Cystectomy Patients Undergoing Preoperative Chemotherapy for Muscle-invasive Bladder Cancer

BACKGROUND

We evaluated the incidence and effect of thromboembolic events (TEEs) in patients with muscle-invasive bladder cancer treated with preoperative chemotherapy (POC) and radical cystectomy (RC) with pelvic lymph node dissection (PLND).

PATIENTS AND METHODS

We performed a retrospective review of all patients who had undergone POC followed by RC plus PLND for muscle-invasive bladder cancer from June 2000 to January 2013 (n = 357). The chemotherapy type (neoadjuvant vs. induction), incidence and timing of TEE diagnosis (preoperatively vs. ≤ 90 days postoperatively), and effect of TEEs on clinical outcomes were recorded.

RESULTS

Overall, 79 patients (22%; 95% confidence interval [CI], 18%-27%) experienced a TEE: 57 (16%) occurred during POC and 22 (6.2%) were diagnosed postoperatively. Forty patients (11%; 95% CI, 8.1%-15%) required an inferior vena cava filter. We found no significant differences in neoadjuvant versus induction chemotherapy and the risk of TEEs (difference, 3.3%; 95% CI, -5% to 12%; P = .5). No significant difference were found in the rates of POC completion according to the presence of a TEE (difference, 1.0%; 95% CI, -11% to 13%; P = .9). The occurrence of TEE did not significantly affect other perioperative outcomes. The risk of recurrence and overall survival were not associated with TEE on multivariable analysis.

CONCLUSION

We found a high incidence of TEEs (22%) in patients undergoing POC before RC plus PLND, with a 16% incidence in the preoperative period. TEEs in the POC setting leads to invasive procedures; however, we did not find a significant effect on POC completion or postoperative complication risk. Further research is required to determine whether preventative TEE measures during POC can improve clinical outcomes.

Validation of an expanded neoantigen identification platform for therapeutic and diagnostic use in immuno-oncology

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Background: Neoantigen identification is increasingly critical for clinical immuno-oncology applications including predicting immunotherapy response and neoantigen-based personalized cancer vaccines. Although standard research pipelines have been developed to aid neoantigen identification, building a robust, validated neoantigen identification platform suitable for clinical applications has been challenging due to the complex processes involved. Methods: To improve neoantigen identification, we extended standard sequencing and informatics methods. We developed an augmented and content enhanced (ACE) exome sequenced at 200X to increase sensitivity to SNPs and indels used for neoantigen identification as well as HLA performance. To accurately identify fusions and variants from RNA, we optimized our ACE transcriptome for FFPE tissue. To improve neoantigen pipelines based on MHC binding algorithms, we developed peptide phasing, high accuracy HLA typing, TCR interaction predictors, and transcript isoform estimation tools to detect neoantigens from indel and fusion events. We performed comprehensive analytical validation of the platform including the ACE Exome, somatic SNV/indel calls, RNA based variant and fusion calls, and HLA typing. This was followed by an overall in silico validation of neoantigen identification using 23 experimentally validated immunogenic neoepitopes spiked into exome data. Results: Analytical validation of our ACE exome platform showed > 97% sensitivity for small variants with a specificity of > 98% at minor allele frequency > 10%. From the ACE transcriptome we achieved a fusion sensitivity of > 99% and RNA based variant calls sensitivity of > 97%. Our ACE exome based HLA typing was 98% and 95% concordant with Class I and II HLA results (respectively) from clinical testing. Our in silico validation of neoantigen predictions resulted in identification of 22 out of 23 immunogenic neoepitopes. Conclusions: We developed sequencing and informatics improvements to standard approaches that can enhance neoantigen identification and demonstrated a comprehensive validation approach that may support neoantigen use in future clinical settings.

The Nrf2/Interleukin-17D axis as a novel target for cancer immune therapy

The oxidative stress-sensing transcription factor Nrf2 has been studied by cancer researchers as a double-edged sword that can either promote or inhibit cancer. Previous findings have shown that Nrf2 can act as a tumor suppressor by detoxifying carcinogens. Paradoxically, when cancer cells express Nrf2, they are protected from oxidative stress and certain chemotherapies, thus explaining why some cancer cells constitutively activate Nrf2 as a tumor promoter. We recently found that the cytokine Interleukin (IL)-17D mediates the recruitment of natural killer (NK) cells to tumor sites, thereby leading to tumor rejection. Here, we show that Nrf2 induced IL-17D in primary tumors and tumor cell lines. Moreover, the known Nrf2-activator tBHQ induced Nrf2 and IL-17D simultaneously, without creating harmful oxidative stress. Applying a tBHQ-containing skin cream to established tumors led to NK cell-mediated tumor regression, and this depended on IL-17D and Nrf2. We propose that the use of tBHQ or other Nrf2 activators can intiate a tumor surveillance pathway involving IL-17D and NK cells, thus mediating cancer regression and bearing potential for cancer immune therapy.

Pediatric Obesity and Cardiometabolic Disorders: Risk Factors and Biomarkers

Obesity remains the most prevailing disorder in childhood males and females worldwide. Its high prevalence markedly predisposes children to insulin resistance, hypertension, hyperlipidemia and liver disorders while enhancing the risk of type 2 diabetes and cardiovascular diseases. In this review, the relationship of obesity with genetic and environmental factors will be described and the underlined causes will briefly be reported. As obesity in children constitutes an increasingly health concern, important potential biomarkers have been discussed for the diagnosis, treatment and follow-up of the wide range of overweight-related complications. Awareness about the applicability and limitations of these preventive and predictive biomarkers will intensify the research and medical efforts for new developments in order to efficiently struggle against childhood obesity.

Whole genome sequencing of an African American family highlights toll like receptor 6 variants in Kawasaki disease susceptibility

Kawasaki disease (KD) is the most common acquired pediatric heart disease. We analyzed Whole Genome Sequences (WGS) from a 6-member African American family in which KD affected two of four children. We sought rare, potentially causative genotypes by sequentially applying the following WGS filters: sequence quality scores, inheritance model (recessive homozygous and compound heterozygous), predicted deleteriousness, allele frequency, genes in KD-associated pathways or with significant associations in published KD genome-wide association studies (GWAS), and with differential expression in KD blood transcriptomes. Biologically plausible genotypes were identified in twelve variants in six genes in the two affected children. The affected siblings were compound heterozygous for the rare variants p.Leu194Pro and p.Arg247Lys in Toll-like receptor 6 (TLR6), which affect TLR6 signaling. The affected children were also homozygous for three common, linked (r² = 1) intronic single nucleotide variants (SNVs) in TLR6 (rs56245262, rs56083757 and rs7669329), that have previously shown association with KD in cohorts of European descent. Using transcriptome data from pre-treatment whole blood of KD subjects (n = 146), expression quantitative trait loci (eQTL) analyses were performed. Subjects homozygous for the intronic risk allele (A allele of TLR6 rs56245262) had differential expression of Interleukin-6 (IL-6) as a function of genotype (p = 0.0007) and a higher erythrocyte sedimentation rate at diagnosis. TLR6 plays an important role in pathogen-associated molecular pattern recognition, and sequence variations may affect binding affinities that in turn influence KD susceptibility. This integrative genomic approach illustrates how the analysis of WGS in multiplex families with a complex genetic disease allows examination of both the common disease–common variant and common disease–rare variant hypotheses.

Monitoring the efficacy of omega-3 supplementation on liver steatosis and carotid intima-media thickness: a pilot study

Purpose

To determine the effects of omega‐3 supplementation on liver fat and carotid intima–media thickness (IMT) and to assess accuracy of ultrasound (US) for grading liver steatosis.

Materials and Methods

In this one‐way crossover pilot study, we assigned children with obesity and liver steatosis to receive 1.2 g daily of omega‐3 supplementation vs. inactive sunflower oil for 24 or 12 weeks. Liver fat content was assessed by magnetic resonance spectroscopy (MRS), magnetic resonance imaging (MRI) and US, and common carotid IMT by US. Statistical analysis included Chi‐square, Student's t‐tests, ANOVA tests and receiver operating characteristic (ROC) curves.

Results

Omega‐3 supplementation was associated with a trend towards decrease in MRS‐determined liver fat fraction (0.7% and 2.1% decrease in the 24‐week and 12‐week omega‐3 group, respectively) compared with the sunflower oil group (1.0% increase). These changes were not significant, whether assessed by MRS (P = 0.508), MRI (P = 0.508) or US (P = 0.678). Using US, the area under the ROC curves were 0.964, 0.817 and 0.783 for distinguishing inferred steatosis grades 0 vs. 1–2–3, 0–1 vs. 2–3 and 0–1–2 vs. 3, respectively, indicating good accuracy of US‐based fat grading. Omega‐3 supplementation was associated with a decrease in US‐determined IMT (0.05‐mm decrease in the 24‐week omega‐3 group. A 0.015‐mm increase was found in the 12‐week omega‐3 group, and a 0.007‐mm decrease in the sunflower oil group (P = 0.003).

Conclusion

Omega‐3 supplementation had no significant effect on liver fat fraction, but led to carotid IMT decrease in children with obesity and liver steatosis.

Usutu virus, Belgium, 2016

During late summer 2016, in a northwest European region extending over Belgium, the Netherlands and the eastern border of the German state of North Rhine Westphalia, an outbreak of wild bird deaths occurred similar to those reported on the continent since 1996. Dead birds were necropsied and examined by complementary methods. Pathologic and immunohistological investigations strongly suggested an infection by Usutu virus. Subsequently, genomic segments of the said virus were detected, the virus was isolated and its complete genome was sequenced. The strain, designated Usutu-LIEGE, is a close phylogenetic relative of those isolated in Germany which form a distinct group within the USUV phylogeny, the so-called Europe_3 lineage. Should this outbreak recapitulate the characteristics of those in southwest Germany in 2011 and in/around Vienna (Austria) in 2001, it is expected that specific avian populations in the affected area will face a significant reduction in size for a few years.

Contrasting Influences of Geographic Range and Distribution of Populations on Patterns of Genetic Diversity in Two Sympatric Pilbara Acacias

The influence of geographic range on species persistence has long been of interest and there is a need for a better understanding of the genetic consequences for species with restricted distributions, particularly with the increasing rate of global species extinctions. However, the genetic effects of restricted range are often confounded by the impacts of population distribution. We compared chloroplast and nuclear genetic diversity and differentiation in two acacias, the restricted, patchily distributed Acacia atkinsiana and the widespread, semi-continuously distributed A. ancistrocarpa. Lower intra-population diversity and higher differentiation between populations were seen in A. atkinsiana compared to its widespread congener, A. ancistrocarpa. There was little evidence of geographical influences on population genetic structure in A. ancistrocarpa whereas A. atkinsiana exhibited nuclear genetic structure with isolation by distance, differentiation of near-coastal populations from those in the ranges, and differentiation of peripheral populations from those in the centre of the distribution. These results are consistent with expectations of the effect of geographic range and population distribution on genetic diversity, but indicate that distribution of populations rather than geographic range has influenced the observed genetic structure. The contrasting patterns observed here demonstrate that conservation approaches for species management and ecological restoration need to consider the distribution of populations in geographically restricted species.

Risk Factors for Ischemic Complications following Pipeline Embolization Device Treatment of Intracranial Aneurysms: Results from the IntrePED Study

BACKGROUND AND PURPOSE

Risk factors for acute ischemic stroke following flow-diverter treatment of intracranial aneurysms are poorly understood. Using the International Retrospective Study of Pipeline Embolization Device (IntrePED) registry, we studied demographic, aneurysm, and procedural characteristics associated with postoperative acute ischemic stroke following Pipeline Embolization Device (PED) treatment.

MATERIALS AND METHODS

We identified patients in the IntrePED registry with post-PED-treatment acute ischemic stroke. The rate of postoperative acute ischemic stroke was determined by demographics, comorbidities, aneurysm characteristics, and procedure characteristics (including anticoagulation use, platelet testing, number of devices used, sheaths, and so forth). Categoric variables were compared with χ(2) testing, and continuous variables were compared with the Student t test. Odds ratios and 95% confidence intervals were obtained by using univariate logistic regression. Multivariate logistic regression analysis was used to determine which factors were independently associated with postoperative stroke.

RESULTS

Of 793 patients with 906 aneurysms, 36 (4.5%) patients had acute ischemic stroke. Twenty-six (72.2%) strokes occurred within 30 days of treatment (median, 3.5 days; range, 0-397 days). Ten patients died, and the remaining 26 had major neurologic morbidity. Variables associated with higher odds of acute ischemic stroke on univariate analysis included male sex, hypertension, treatment of MCA aneurysms, treatment of fusiform aneurysms, treatment of giant aneurysms, and use of multiple PEDs. However, on multivariate analysis, the only one of these variables independently associated with stroke was treatment of fusiform aneurysms (OR, 2.74; 95% CI, 1.11-6.75; P = .03). Fusiform aneurysms that were associated with stroke were significantly larger than those not associated with stroke (mean, 24.5 ± 12.5 mm versus 13.6 ± 6.8 mm; P < .001).

CONCLUSIONS

Ischemic stroke following PED treatment is an uncommon-but-devastating complication. Fusiform aneurysms were the only variable independently associated with postoperative stroke.

Nrf2 Induces IL-17D to Mediate Tumor and Virus Surveillance

Cells undergoing xenobiotic or oxidative stress activate the transcription factor nuclear factor erythroid-derived 2-like 2 (Nrf2), which initiates an intrinsic "stress surveillance" pathway. We recently found that the cytokine IL-17D effects a form of extrinsic stress surveillance by inducing antitumor immunity, but how IL-17D is regulated remains unknown. Here, we show that Nrf2 induced IL-17D in cancer cell lines. Moreover, both Nrf2 and IL-17D were induced in primary tumors as well as during viral infection in vivo. Expression of IL-17D in tumors and virally infected cells is essential for optimal protection of the host as il17d(-/-) mice experienced a higher incidence of tumors and exacerbated viral infections compared to wild-type (WT) animals. Moreover, activating Nrf2 to induce IL-17D in established tumors led to natural killer cell-dependent tumor regression. These data demonstrate that Nrf2 can initiate both intrinsic and extrinsic stress surveillance pathways and highlight the use of Nrf2 agonists as immune therapies for cancer and infection.

Longitudinal circulating concentrations of long-chain polyunsaturated fatty acids in the third trimester of pregnancy in gestational diabetes

AIM

Gestational diabetes mellitus is a common complication of pregnancy. Long-chain polyunsaturated fatty acids (LCPUFA) are essential for fetal neurodevelopment. Docosahexaenoic acid (DHA) is the predominant n-3 LCPUFA in the brain and retina. Circulating absolute concentrations of total n-3 and n-6 LCPUFAs rise during normal pregnancy. It remains unclear whether gestational diabetes may affect the normal rise in circulating concentrations of LCPUFAs in the third trimester of pregnancy - a period of rapid fetal neurodevelopment. This study aimed to address this question.

METHODS

In a prospective singleton pregnancy cohort, fatty acids in fasting plasma total lipids were measured at 24-28 and 32-35 weeks of gestation in women with (n = 24) and without gestational diabetes mellitus (n = 116). Fatty acid desaturase activity indices were estimated by relevant product-to-precursor fatty acid ratios. Dietary nutrient intakes were estimated by a food frequency questionnaire.

RESULTS

Plasma absolute concentrations of total n-6 LCPUFAs rose significantly between 24-28 and 32-35 weeks of gestation in women with or without gestational diabetes, whereas total n-3 LCPUFAs and DHA concentrations rose significantly only in women without gestational diabetes (all P < 0.01). Delta-5 desaturase indices (20:4n-6/20:3n-6) were similar, but delta-6 desaturase indices (18:3n-6/18:2n-6) were significantly lower in women with gestational diabetes at 32-35 weeks of gestation. Dietary intakes of all fatty acids were comparable.

CONCLUSION

The normal rise in circulating absolute concentrations of DHA and total n-3 LCPUFAs in the third trimester of pregnancy may be compromised in gestational diabetes, probably due to impaired synthesis or mobilization rather than dietary intake difference.

Modulation of tumor eIF4E by antisense inhibition: A phase I/II translational clinical trial of ISIS 183750-an antisense oligonucleotide against eIF4E-in combination with irinotecan in solid tumors and irinotecan-refractory colorectal cancer

The eukaryotic translation initiation factor 4E (eIF4E) is a potent oncogene that is found to be dysregulated in 30% of human cancer, including colorectal carcinogenesis (CRC). ISIS 183750 is a second-generation antisense oligonucleotide (ASO) designed to inhibit the production of the eIF4E protein. In preclinical studies we found that EIF4e ASOs reduced expression of EIF4e mRNA and inhibited proliferation of colorectal carcinoma cells. An additive antiproliferative effect was observed in combination with irinotecan. We then performed a clinical trial evaluating this combination in patients with refractory cancer. No dose-limiting toxicities were seen but based on pharmacokinetic data and tolerability the dose of irinotecan was reduced to 160 mg/m(2) biweekly. Efficacy was evaluated in 15 patients with irinotecan-refractory colorectal cancer. The median time of disease control was 22.1 weeks. After ISIS 183750 treatment, peripheral blood levels of eIF4E mRNA were decreased in 13 of 19 patients. Matched pre- and posttreatment tumor biopsies showed decreased eIF4E mRNA levels in five of nine patients. In tumor tissue, the intracellular and stromal presence of ISIS 183750 was detected by IHC in all biopsied patients. Although there were no objective responses stable disease was seen in seven of 15 (47%) patients who were progressing before study entry, six of whom were stable at the time of the week 16 CT scan. We were also able to confirm through mandatory pre- and posttherapy tumor biopsies penetration of the ASO into the site of metastasis.

TICI and Age: What's the Score?

BACKGROUND AND PURPOSE

Previous studies have suggested that advanced age predicts worse outcome following mechanical thrombectomy. We assessed outcomes from 2 recent large prospective studies to determine the association among TICI, age, and outcome.

MATERIALS AND METHODS

Data from the Solitaire FR Thrombectomy for Acute Revascularization (STAR) trial, an international multicenter prospective single-arm thrombectomy study and the Solitaire arm of the Solitaire FR With the Intention For Thrombectomy (SWIFT) trial were pooled. TICI was determined by core laboratory review. Good outcome was defined as an mRS score of 0-2 at 90 days. We analyzed the association among clinical outcome, successful-versus-unsuccessful reperfusion (TICI 2b-3 versus TICI 0-2a), and age (dichotomized across the median).

RESULTS

Two hundred sixty-nine of 291 patients treated with Solitaire in the STAR and SWIFT data bases for whom TICI and 90-day outcome data were available were included. The median age was 70 years (interquartile range, 60-76 years) with an age range of 25-88 years. The mean age of patients 70 years of age or younger was 59 years, and it was 77 years for patients older than 70 years. There was no significant difference between baseline NIHSS scores or procedure time metrics. Hemorrhage and device-related complications were more common in the younger age group but did not reach statistical significance. In absolute terms, the rate of good outcome was higher in the younger population (64% versus 44%, P < .001). However, the magnitude of benefit from successful reperfusion was higher in the 70 years of age and older group (OR, 4.82; 95% CI, 1.32-17.63 versus OR 7.32; 95% CI, 1.73-30.99).

CONCLUSIONS

Successful reperfusion is the strongest predictor of good outcome following mechanical thrombectomy, and the magnitude of benefit is highest in the patient population older than 70 years of age.

I don't want the money, I just want your time: How moral identity overcomes the aversion to giving time to prosocial causes

Four studies show that moral identity reduces people's aversion to giving time-particularly as the psychological costs of doing so increase. In Study 1, we demonstrate that even when the cost of time and money are held equivalent, a moral cue enhances the expected self-expressivity of giving time-especially when it is given to a moral cause. We found that a moral cue reduces time aversion even when giving time was perceived to be unpleasant (Study 2), or when the time to be given was otherwise seen to be scarce (Study 3). Study 4 builds on these studies by examining actual giving while accounting for the real costs of time. In this study, we found that the chronic salience of moral identity serves as a buffer to time aversion, specifically as giving time becomes increasingly costly. These findings are discussed in terms of the time-versus-money literature and the identity literature. We also discuss policy implications for prosocial cause initiatives. (PsycINFO Database Record

Plasma fatty acid composition in French-Canadian children with non-alcoholic fatty liver disease: Effect of n-3 PUFA supplementation

Non-alcoholic fatty liver disease (NAFLD) represents one of the most common causes of liver disease worldwide. As the NAFLD pathogenesis is associated with diet and lifestyle, the aims of the present work are to assess fatty acid (FA) composition in NAFLD young French-Canadian, to determine whether treatment with n-3 FA improves the plasma FA profile, and to define the time on the effectiveness of n-3 FA supplementation. Baseline characteristics of the NAFLD subjects show increased, anthropometric and biochemical parameters. Their plasma FA composition is characterized by a percent increase in total n-6 FA and a high proportion of saturated and total monounsaturated FA, as well as a decrease in Δ5 and increase in Δ6 desaturases. In conclusion, our results document for the first time the composition of plasma FAs in NAFLD young French Canadian and the efficacy of 3-month supplementation to improve the proportion of n-3 FA in their plasma.