Cardiac Substrate Utilization and Relationship to Invasive Exercise Hemodynamic Parameters in HFpEF.

The authors conducted transcardiac blood sampling in healthy subjects and subjects with heart failure with preserved ejection fraction (HFpEF) to compare cardiac metabolite and lipid substrate use. We demonstrate that fatty acids are less used by HFpEF hearts and that lipid extraction is influenced by hemodynamic factors including pulmonary pressures and cardiac index. The release of many products of protein catabolism is apparent in HFpEF compared to healthy myocardium. In subgroup analyses, differences in energy substrate use between female and male hearts were identified.

Identification of aberrant luminal progenitors and mTORC1 as a potential breast cancer prevention target in BRCA2 mutation carriers.

Inheritance of a BRCA2 pathogenic variant conveys a substantial life-time risk of breast cancer. Identification of the cell(s)-of-origin of BRCA2-mutant breast cancer and targetable perturbations that contribute to transformation remains an unmet need for these individuals who frequently undergo prophylactic mastectomy. Using preneoplastic specimens from age-matched, premenopausal females, here we show broad dysregulation across the luminal compartment in BRCA2mut/+ tissue, including expansion of aberrant ERBB3lo luminal progenitor and mature cells, and the presence of atypical oestrogen receptor (ER)-positive lesions. Transcriptional profiling and functional assays revealed perturbed proteostasis and translation in ERBB3lo progenitors in BRCA2mut/+ breast tissue, independent of ageing. Similar molecular perturbations marked tumours bearing BRCA2-truncating mutations. ERBB3lo progenitors could generate both ER+ and ER- cells, potentially serving as cells-of-origin for ER-positive or triple-negative cancers. Short-term treatment with an mTORC1 inhibitor substantially curtailed tumorigenesis in a preclinical model of BRCA2-deficient breast cancer, thus uncovering a potential prevention strategy for BRCA2 mutation carriers.

A dual-channel fluorescence probe for simultaneously visualizing cysteine and viscosity during drug-induced hepatotoxicity.

Cysteine (Cys), one of the important participants in protecting cells from oxidative stress, is closely associated with the occurrence and development of various diseases. Moreover, cell viscosity as a pivotal microenvironmental parameter has recently attracted increasing attention due to its dominant role in governing intracellular signal transduction and diffusion of reactive metabolites. Thus, simultaneous detection of Cys and viscosity is imperative for investigating their pathophysiological functions and cross-link. Herein we present a mitochondria-targetable dual-channel fluorescence probe ABDSP by grafting the acrylate modified pyridinium unit to dimethylaminobenzene. Whilst the probe is a seemingly simple, it could simultaneously discriminate Cys and viscosity in a fashion of distinguishable signals. Furthermore, the probe was successfully employed for visualizing mitochondrial Cys and viscosity, and probe into their cross-link during acetaminophen-induced hepatotoxicity.

Neither random nor censored: estimating intensity-dependent probabilities for missing values in label-free proteomics.

MOTIVATION: Mass spectrometry proteomics is a powerful tool in biomedical research but its usefulness is limited by the frequent occurrence of missing values in peptides that cannot be reliably quantified (detected) for particular samples. Many analysis strategies have been proposed for missing values where the discussion often focuses on distinguishing whether values are missing completely at random (MCAR), missing at random (MAR) or missing not at random (MNAR). RESULTS: Statistical models and algorithms are proposed for estimating the detection probabilities and for evaluating how much statistical information can or cannot be recovered from the missing value pattern. The probability that an intensity is detected is shown to be accurately modeled as a logit-linear function of the underlying intensity, showing that missing value process is intermediate between MAR and censoring. The detection probability asymptotes to 100% for high intensities, showing that missing values unrelated to intensity are rare. The rule applies globally to each dataset and is appropriate for both high and lowly expressed peptides. A probability model is developed that allows the distribution of unobserved intensities to be inferred from the observed values. The detection probability model is incorporated into a likelihood-based approach for assessing differential expression and successfully recovers statistical power compared to omitting the missing values from the analysis. In contrast, imputation methods are shown to perform poorly, either reducing statistical power or increasing the false discovery rate to unacceptable levels. AVAILABILITY AND IMPLEMENTATION: Data and code to reproduce the results shown in this article are available from https://mengbo-li.github.io/protDP/.

A DFT study of plasma-catalytic ammonia synthesis: the effect of electric fields, excess electrons and catalyst surfaces on N2 dissociation.

Plasma catalytic synthesis of ammonia has the advantages of flexible on-off and environmental friendliness, making ammonia a potential vector for renewable energy storage. The synergistic interaction between plasmas and catalyst surfaces remains unclear. In this work, we develop a quantum chemical model based on density functional theory where the plasma environment is simplified. The effect of electric fields and surface electrons on N2 adsorption and dissociation is studied on the typical catalysts (Ru and Ni) with different surface morphologies. The combined effect of the electric fields and excess electrons will promote the adsorption of N2 and the weakening of the NN triple bond. It is shown that the electron distribution on the surface is optimized, and the electrostatic interaction between surface atoms and adsorbates is strengthened. The marginal effect has been observed, and the promotion effect on the catalysts with better performance in thermal-catalytic N2 dissociation is weaker.

Effect of chronic exercise in healthy young male adults: a metabolomic analysis.

AIMS: To examine the metabolic adaptation to an 80-day exercise intervention in healthy young male adults where lifestyle factors such as diet, sleep, and physical activities are controlled. METHODS AND RESULTS: This study involved cross-sectional analysis before and after an 80-day aerobic and strength exercise intervention in 52 young, adult, male, newly enlisted soldiers in 2015. Plasma metabolomic analyses were performed using liquid chromatography, tandem mass spectrometry. Data analyses were performed between March and August 2019. We analysed changes in metabolomic profiles at the end of an 80-day exercise intervention compared to baseline, and the association of metabolite changes with changes in clinical parameters. Global metabolism was dramatically shifted after the exercise training programme. Fatty acids and ketone body substrates, key fuels used by exercising muscle, were dramatically decreased in plasma in response to increased aerobic fitness. There were highly significant changes across many classes of metabolic substrates including lipids, ketone bodies, arginine metabolites, endocannabinoids, nucleotides, markers of proteolysis, products of fatty acid oxidation, microbiome-derived metabolites, markers of redox stress, and substrates of coagulation. For statistical analyses, a paired t-test was used and Bonferroni-adjusted P-value of <0.0004 was considered to be statistically significant. The metabolite dimethylguanidino valeric acid (DMGV) (recently shown to predict lack of metabolic response to exercise) tracked maladaptive metabolic changes to exercise; those with increases in DMGV levels had increases in several cardiovascular risk factors; changes in DMGV levels were significantly positively correlated with increases in body fat (P = 0.049), total and LDL cholesterol (P = 0.003 and P = 0.007), and systolic blood pressure (P = 0.006). This study was approved by the Departments of Defence and Veterans' Affairs Human Research Ethics Committee and written informed consent was obtained from each subject. CONCLUSION: For the first time, the true magnitude and extent of metabolic adaptation to chronic exercise training are revealed in this carefully designed study, which can be leveraged for novel therapeutic strategies in cardiometabolic disease. Extending the recent report of DMGV's predictive utility in sedentary, overweight individuals, we found that it is also a useful marker of poor metabolic response to exercise in young, healthy, fit males.

Plasma levels of trimethylamine-N-oxide can be increased with 'healthy' and 'unhealthy' diets and do not correlate with the extent of atherosclerosis but with plaque instability.

AIMS: The microbiome-derived metabolite trimethylamine-N-oxide (TMAO) has attracted major interest and controversy both as a diagnostic biomarker and therapeutic target in atherothrombosis. METHODS AND RESULTS: Plasma TMAO increased in mice on 'unhealthy' high-choline diets and notably also on 'healthy' high-fibre diets. Interestingly, TMAO was found to be generated by direct oxidation in the gut in addition to oxidation by hepatic flavin-monooxygenases. Unexpectedly, two well-accepted mouse models of atherosclerosis, ApoE-/- and Ldlr-/- mice, which reflect the development of stable atherosclerosis, showed no association of TMAO with the extent of atherosclerosis. This finding was validated in the Framingham Heart Study showing no correlation between plasma TMAO and coronary artery calcium score or carotid intima-media thickness (IMT), as measures of atherosclerosis in human subjects. However, in the tandem-stenosis mouse model, which reflects plaque instability as typically seen in patients, TMAO levels correlated with several characteristics of plaque instability, such as markers of inflammation, platelet activation, and intraplaque haemorrhage. CONCLUSIONS: Dietary-induced changes in the microbiome, of both 'healthy' and 'unhealthy' diets, can cause an increase in the plasma level of TMAO. The gut itself is a site of significant oxidative production of TMAO. Most importantly, our findings reconcile contradictory data on TMAO. There was no direct association of plasma TMAO and the extent of atherosclerosis, both in mice and humans. However, using a mouse model of plaque instability we demonstrated an association of TMAO plasma levels with atherosclerotic plaque instability. The latter confirms TMAO as being a marker of cardiovascular risk.

Core functional nodes and sex-specific pathways in human ischaemic and dilated cardiomyopathy.

Poor access to human left ventricular myocardium is a significant limitation in the study of heart failure (HF). Here, we utilise a carefully procured large human heart biobank of cryopreserved left ventricular myocardium to obtain direct molecular insights into ischaemic cardiomyopathy (ICM) and dilated cardiomyopathy (DCM), the most common causes of HF worldwide. We perform unbiased, deep proteomic and metabolomic analyses of 51 left ventricular (LV) samples from 44 cryopreserved human ICM and DCM hearts, compared to age-, gender-, and BMI-matched, histopathologically normal, donor controls. We report a dramatic reduction in serum amyloid A1 protein in ICM hearts, perturbed thyroid hormone signalling pathways and significant reductions in oxidoreductase co-factor riboflavin-5-monophosphate and glycolytic intermediate fructose-6-phosphate in both; unveil gender-specific changes in HF, including nitric oxide-related arginine metabolism, mitochondrial substrates, and X chromosome-linked protein and metabolite changes; and provide an interactive online application as a publicly-available resource.

miR-185 inhibits prostate cancer angiogenesis induced by the nodal/ALK4 pathway.

BACKGROUND: Inhibition of angiogenesis in prostatic cancer could be a brand-new method to suppress tumour progression. Nodal/ALK4 has been associated with vascularization in many cancers. However, the relationship between and role of Nodal/ALK4 and miR-185 in human prostatic cancer is still unknown. METHODS: Prostatic cancer DU145 cells and LNCaP cells were used to investigate the angiogenic effect induced by Nodal and the anti-angiogenic roles of miR-185. Colony formation assay, MTT assay, transwell assay and tube formation assay were used to explore cell proliferation, migration and tube-forming ability, respectively. A luciferase reporter assay confirmed the binding relationship between miR-185 and ALK4. The expression levels of miR-185, ALK4 and VEGF were detected by qRT-PCR and Western blotting. The effects of miR-185 and Nodal in prostate cancer were also investigated in animal experiments. RESULTS: VEGF expression was increased in DU145 cells and LNCaP cells after Nodal incubation, and Nodal activated the proliferation ability of prostatic cancer cells and the migration and tube-forming ability of human umbilical vein endothelial cells (HUVECs), which were all inhibited by treatment with the Nodal inhibitor SB431524. Bioinformatics analysis and luciferase assay were used to verify miR-185 as a target of ALK4. Prostatic cancer cell proliferation was inhibited by overexpression of miR-185, which was shown to regulate the migration and angiogenesis of HUVECs by targeting ALK4 for suppression. miR-185 also showed a significant inverse correlation with Nodal treatment and reversed the angiogenic effects induced by Nodal. More importantly, for the first time, xenograft experiments indicated that overexpression of miR-185 suppressed tumour development. CONCLUSION: The Nodal/ALK4 pathway is important in the angiogenesis of prostate cancer and can be inhibited by targeting miR-185 to downregulate ALK4. These findings provide a new perspective on the mechanism of prostate cancer formation.

Metabolites downstream of predicted loss-of-function variants inform relationship to disease.

A small minority (< 3%) of protein-coding genetic variants are predicted to lead to loss of protein function. However, these predicted loss-of-function (pLOF) variants can provide insight into mode of transcriptional effect. To examine how these changes are propagated to phenotype, we determined associations with downstream metabolites. We performed association analyses of 37 pLOF variants - previously reported to be significantly associated with disease in >400,000 subjects in UK Biobank - with metabolites. We conducted these analyses in three community-based cohorts: the Framingham Heart Study (FHS) Offspring Cohort, FHS Generation 3, and the KORA F4 cohort. We identified 19 new low-frequency or rare (minor allele frequency (MAF) <5%) pLOF variant-metabolite associations, and 12 new common (MAF > 5%) pLOF variant-metabolite associations. Rare pLOF variants in the genes BTN3A2, ENPEP, and GEM that have been associated with blood pressure in UK Biobank, were associated with vasoactive metabolites indoxyl sulfate, asymmetric dimethylarginine (ADMA), and with niacinamide, respectively. A common pLOF variant in gene CCHCR1, associated with asthma in UK Biobank, was associated with histamine and niacinamide in FHS Generation 3, both reported to play a role in this disease. Common variants in olfactory receptor gene OX4C11 that associated with blood pressure in UK Biobank were associated with the nicotine metabolite cotinine, suggesting an interaction between altered olfaction, smoking behaviour, and blood pressure. These findings provide biological validity for pLOF variant-disease associations, and point to the effector roles of common metabolites. Such an approach may provide novel disease markers and therapeutic targets.

The incidence and prevalence of medical device-related pressure ulcers in intensive care: a systematic review.

OBJECTIVE: The objective of this review was to synthesise the literature and evaluate the incidence, prevalence and severity of medical device-related pressure ulcers (MDRPU) in adult intensive care patients. METHOD: Electronic databases and additional grey literature were searched for publications between 2000 and 2017. Outcome measures included cumulative incidence or incidence rate, point prevalence or period prevalence as a primary outcome and the severity and location of the pressure ulcer (PU) as secondary outcome measures. Included studies were assessed for risk of bias using a nine-item checklist for prevalence studies. The heterogeneity was evaluated using 12 statistic. RESULTS: We included 13 studies in this review. Prevalence was reported more frequently than incidence. Pooled data demonstrated a high variation in the incidence and prevalence rates ranging from 0.9% to 41.2% in incidence and 1.4% to 121% in prevalence. Heterogeneity was high. Mucosal pressure injuries were the most common stage reported in the incidence studies whereas category II followed by category I were most commonly reported in the prevalence studies. In the incidence studies, the most common location was the ear and in the prevalence studies it was the nose. CONCLUSION: While MDRPU are common in intensive care patients, it is an understudied area. Inconsistency in the staging of MDRPU, along with variations in data collection methods, study design and reporting affect the reported incidence and prevalence rates. Standardisation of data reporting and collection method is essential for pooling of future studies.

Significant association of PD-L1 expression with human papillomavirus positivity and its prognostic impact in oropharyngeal cancer.

BACKGROUND: The programmed death pathway plays a role in persistent human papillomavirus (HPV) infection as well as in resistance to immune elimination during malignant progression. In this study, we examined PD-L1 expression by immunohistochemistry and tumour infiltrating lymphocytes (TIL) in 214 patients with oropharyngeal squamous cell cancer (OPSCC) to assess its clinical significance. RESULTS: HPV-positive OPSCC were significantly more likely to express PD-L1 than HPV-negative OPSCC (85.2% vs 57.1%, p < 0.05). PD-L1 staining was more likely to be associated with TILs in HPV-positive OPSCC (67.9% vs 49.6%, p = 0.01). Relative to those patients with HPV-positive/PD-L1-positive OPSCC, patients with HPV negative/PD-L1 negative OPSCC were 6.4 times more likely to develop a local recurrence, 5.8 times more likely to develop an event and 6.5 times more likely to die. Within the HPV positive cases, PD-L1 expression also significantly impacted on the outcomes with PD-L1 negative cases more likely to develop a locoregional recurrence (HR 4.16), to have an event (HR 2.5) and to die (HR 3.16). Evidence of an interaction between HPV status and PD-L1 expression was found for overall survival (p < 0.005). CONCLUSION: Our findings suggested that different immune profiles in oropharyngeal cancer by HPV status and the effect of HPV on the outcomes is modified by PD-L1 expression.

Molecular cloning and characterization of two genes encoding peroxiredoxins from freshwater bivalve Anodonta woodiana: Antioxidative effect and immune defense.

Members of Prx family function as an important players in host defense against oxidative stress, and modulate immune responses. In the current study, two complete Prx sequences were isolated from bivalve Anodonta woodiana and respectively named AwPrx4a and AwPrx4b. Regulative characterizations of AwPrx4a and AwPrx4b derived from perfluorooctanesulfonate (PFOS), perfluoroocanoic acid (PFOA), lipopolysaccharide (LPS) and polyinosinic:polycytidylic (Poly I:C) challenge in hepatopancreas, gill and hemocytes were measured by quantitative real-time PCR, respectively. The full-length cDNA of AwPrx4a had an open reading frame ORF of 588 bp encoding 196 amino acids. Two highly conserved Prxs signature motifs were observed in deduced amino acid sequence, one was FYPLDFTFACPTEI, and the other was GEVCPA. Complete cDNA sequence of AwPrx4b was comprised of a 5' untranslated region (UTR) of 120 nucleotides, a 426 bp ORF which was encoded 142 amino acids, and a long 3'-UTR of 412 nucleotides. Expressions of AwPrx4a and AwPrx4b showed a significant up-regulation pattern in groups at lower concentration treatment of PFOS and PFOA, a biphasic profile in groups with a higher concentration treatment. Compared with that of control group, expressions of AwPrx4a and AwPrx4b were significantly induced by LPS and Poly I:C treatment in the hepatopancreas, gill and hemocytes. These results indicate up-regulations of AwPrx4a and AwPrx4b expression are associated with eliminating oxidative stress derived from PFOS and PFOA administration as well as enhancing immune defense against LPS and Poly I:C challenge.