Differential Impact In Vivo of Pf4-ΔCre-Mediated and Gp1ba-ΔCre-Mediated Depletion of Cyclooxygenase-1 in Platelets in Mice

BACKGROUND

Low-dose aspirin is widely used for the secondary prevention of cardiovascular disease. The beneficial effects of low-dose aspirin are attributable to its inhibition of platelet Cox (cyclooxygenase)-1-derived thromboxane A2. Until recently, the use of the Pf4 (platelet factor 4) Cre has been the only genetic approach to generating megakaryocyte/platelet ablation of Cox-1 in mice. However, Pf4-ΔCre displays ectopic expression outside the megakaryocyte/platelet lineage, especially during inflammation. The use of the Gp1ba (glycoprotein 1bα) Cre promises a more specific, targeted approach.

METHODS

To evaluate the role of Cox-1 in platelets, we crossed Pf4-ΔCre or Gp1ba-ΔCre mice with Cox-1flox/flox mice to generate platelet Cox-1-/- mice on normolipidemic and hyperlipidemic (Ldlr-/-) backgrounds.

RESULTS

Ex vivo platelet aggregation induced by arachidonic acid or adenosine diphosphate in platelet-rich plasma was inhibited to a similar extent in Pf4-ΔCre Cox-1-/-/Ldlr-/- and Gp1ba-ΔCre Cox-1-/-/Ldlr-/- mice. In a mouse model of tail injury, Pf4-ΔCre-mediated and Gp1ba-ΔCre-mediated deletions of Cox-1 were similarly efficient in suppressing platelet prostanoid biosynthesis. Experimental thrombogenesis and attendant blood loss were similar in both models. However, the impact on atherogenesis was divergent, being accelerated in the Pf4-ΔCre mice while restrained in the Gp1ba-ΔCres. In the former, accelerated atherogenesis was associated with greater suppression of PGI2 biosynthesis, a reduction in the lipopolysaccharide-evoked capacity to produce PGE2 and PGD2, activation of the inflammasome, elevated plasma levels of IL-1β, reduced plasma levels of HDL-C, and a reduction in the capacity for reverse cholesterol transport. By contrast, in the latter, plasma HDL-C and α-tocopherol were elevated, and MIP-1α (macrophage inflammatory protein-1α) and MCP-1 (monocyte chemoattractant protein 1) were reduced.

CONCLUSIONS

Both approaches to Cox-1 deletion similarly restrain thrombogenesis, but a differential impact on Cox-1-dependent prostanoid formation by the vasculature may contribute to an inflammatory phenotype and accelerated atherogenesis in Pf4-ΔCre mice.

Age-regulated cycling metabolites are relevant for behavior

Circadian cycles of sleep:wake and gene expression change with age in all organisms examined. Metabolism is also under robust circadian regulation, but little is known about how metabolic cycles change with age and whether these contribute to the regulation of behavioral cycles. To address this gap, we compared cycling of metabolites in young and old Drosophila and found major age-related variations. A significant model separated the young metabolic profiles by circadian timepoint, but could not be defined for the old metabolic profiles due to the greater variation in this dataset. Of the 159 metabolites measured in fly heads, we found 17 that cycle by JTK analysis in young flies and 17 in aged. Only four metabolites overlapped in the two groups, suggesting that cycling metabolites are distinct in young and old animals. Among our top cyclers exclusive to young flies were components of the pentose phosphate pathway (PPP). As the PPP is important for buffering reactive oxygen species, and overexpression of glucose-6-phosphate dehydrogenase (G6PD), a key component of the PPP, was previously shown to extend lifespan in Drosophila, we asked if this manipulation also affects sleep:wake cycles. We found that overexpression in circadian clock neurons decreases sleep in association with an increase in cellular calcium and mitochondrial oxidation, suggesting that altering PPP activity affects neuronal activity. Our findings elucidate the importance of metabolic regulation in maintaining patterns of neural activity, and thereby sleep:wake cycles.

Sleep deprivation and aging are metabolically linked across tissues

STUDY OBJECTIVES

Insufficient sleep is a concerning hallmark of modern society because sleep deprivation (SD) is a risk factor for neurodegenerative and cardiometabolic disorders. SD imparts an aging-like effect on learning and memory, although little is known about possible common molecular underpinnings of SD and aging. Here, we examine this question by profiling metabolic features across different tissues after acute SD in young adult and aged mice.

METHODS

Young adult and aged mice were subjected to acute SD for 5 hours. Blood plasma, hippocampus, and liver samples were subjected to UPLC-MS/MS-based metabolic profiling.

RESULTS

SD preferentially impacts peripheral plasma and liver profiles (e.g. ketone body metabolism) whereas the hippocampus is more impacted by aging. We further demonstrate that aged animals exhibit SD-like metabolic features at baseline. Hepatic alterations include parallel changes in nicotinamide metabolism between aging and SD in young animals. Overall, metabolism in young adult animals is more impacted by SD, which in turn induces aging-like features. A set of nine metabolites was classified (79% correct) based on age and sleep status across all four groups.

CONCLUSIONS

Our metabolic observations demonstrate striking parallels to previous observations in studies of learning and memory and define a molecular metabolic signature of sleep loss and aging.

Glucose Challenge Uncovers Temporal Fungibility of Metabolic Homeostasis Throughout the Day

Rhythmicity is a central feature of behavioral and biological processes including metabolism, however, the mechanisms of metabolite cycling are poorly understood. A robust oscillation in a network of key metabolite pathways downstream of glucose is described in humans, then these pathways mechanistically probed through purpose-built 13C6-glucose isotope tracing in Drosophila every 4h. A temporal peak in biosynthesis was noted by broad labelling of pathways downstream of glucose in wild-type flies shortly following lights on. Krebs cycle labelling was generally increased in a hyperactive mutant (fumin) along with glycolysis labelling primarily observed at dawn. Surprisingly, neither underlying feeding rhythms nor the presence of food explains the rhythmicity of glucose processing across genotypes. These results are consistent with clinical data demonstrating detrimental effects of mis-timed energy intake. This approach provides a window into the dynamic range of metabolic processing ability through the day and mechanistic basis for exploring circadian metabolic homeostasis in disease states.

Altered Metabolism During the Dark Period in Drosophila Short Sleep Mutants

Sleep is an almost universally required state in biology. Disrupted sleep has been associated with adverse health risks including metabolic perturbations. Sleep is in part regulated via circadian mechanisms, however, metabolic dysfunction at different times of day arising from sleep disruption is unclear. We used targeted liquid chromatography-mass spectrometry to probe metabolic alterations using high-resolution temporal sampling of two Drosophila short sleep mutants, fumin and sleepless, across a circadian day. Discriminant analyses revealed overall distinct metabolic profiles for mutants when compared to a wild type dataset. Altered levels of metabolites involved in nicotinate/nicotinamide, alanine, aspartate, and glutamate, glyoxylate and dicarboxylate metabolism, and the TCA cycle were observed in mutants suggesting increased energetic demands. Furthermore, rhythmicity analyses revealed fewer 24 hr rhythmic metabolites in both mutants. Interestingly, mutants displayed two major peaks in phases while wild type displayed phases that were less concerted. In contrast to 24 hr rhythmic metabolites, an increase in the number of 12 hr rhythmic metabolites was observed in fumin while sleepless displayed a decrease. These results support that decreased sleep alters the overall metabolic profile with short sleep mutants displaying altered metabolite levels associated with a number of pathways in addition to altered neurotransmitter levels.

Deep phenotyping of the lipidomic response in COVID-19 and non-COVID-19 sepsis

BACKGROUND

Lipids may influence cellular penetrance by viral pathogens and the immune response that they evoke. We deeply phenotyped the lipidomic response to SARs-CoV-2 and compared that with infection with other pathogens in patients admitted with acute respiratory distress syndrome to an intensive care unit (ICU).

METHODS

Mass spectrometry was used to characterise lipids and relate them to proteins, peripheral cell immunotypes and disease severity.

RESULTS

Circulating phospholipases (sPLA2, cPLA2 (PLA2G4A) and PLA2G2D) were elevated on admission in all ICU groups. Cyclooxygenase, lipoxygenase and epoxygenase products of arachidonic acid (AA) were elevated in all ICU groups compared with controls. sPLA2 predicted severity in COVID-19 and correlated with TxA2, LTE4 and the isoprostane, iPF2α-III, while PLA2G2D correlated with LTE4. The elevation in PGD2, like PGI2 and 12-HETE, exhibited relative specificity for COVID-19 and correlated with sPLA2 and the interleukin-13 receptor to drive lymphopenia, a marker of disease severity. Pro-inflammatory eicosanoids remained correlated with severity in COVID-19 28 days after admission. Amongst non-COVID ICU patients, elevations in 5- and 15-HETE and 9- and 13-HODE reflected viral rather than bacterial disease. Linoleic acid (LA) binds directly to SARS-CoV-2 and both LA and its di-HOME products reflected disease severity in COVID-19. In healthy marines, these lipids rose with seroconversion. Eicosanoids linked variably to the peripheral cellular immune response. PGE2, TxA2 and LTE4 correlated with T cell activation, as did PGD2 with non-B non-T cell activation. In COVID-19, LPS stimulated peripheral blood mononuclear cell PGF2α correlated with memory T cells, dendritic and NK cells while LA and DiHOMEs correlated with exhausted T cells. Three high abundance lipids - ChoE 18:3, LPC-O-16:0 and PC-O-30:0 - were altered specifically in COVID. LPC-O-16:0 was strongly correlated with T helper follicular cell activation and all three negatively correlated with multi-omic inflammatory pathways and disease severity.

CONCLUSIONS

A broad based lipidomic storm is a predictor of poor prognosis in ARDS. Alterations in sPLA2, PGD2 and 12-HETE and the high abundance lipids, ChoE 18:3, LPC-O-16:0 and PC-O-30:0 exhibit relative specificity for COVID-19 amongst such patients and correlate with the inflammatory response to link to disease severity.

Customized Surface Design to Increase Throughput of Ambient Ionization Mass Spectrometry Lipidomics

Increased access to cheap and rapid mass spectrometry testing of biofluids is desirable for the analysis of disorders and diseases that may be linked to alterations in metabolite or lipid levels. The objective of this study is to establish an easily customized high-throughput workflow for the analysis of biological samples using desorption electrospray ionization-mass spectrometry (DESI-MS). The guiding principles of this workflow are the use of low-cost, open-source, and readily accessible materials with high-throughput and reproducibility. The design consists of 3 steps: (1) PARAFILM surface customization of size, shape, and depth of features on PARAFILM via 3D printed molds; (2) sample spotting via high-throughput robotics using the relatively inexpensive and open-source Opentrons platform to reduce variability and increase reliability of sample spotting; and (3) an open-source point-and-click graphical user interface (MSI.EAGLE) for data analysis via the R statistical language building on the Cardinal package. Here we describe this workflow and test optimal surface ionization characteristics by comparison of serum extracts spotted on PARAFILM and on PTFE (porous and nonporous). Untargeted analysis across three surfaces suggests that they are all suitable for ionization of a wide range of metabolites and lipids, with 3983 m/z features detected. Differential analysis of polar vs nonpolar serum extracts suggests that ∼80% of ions are desorbed preferentially from different surfaces. PARAFILM is less impacted by the interference of background ions derived from the surface. The developed system allows for a wide range of researchers to access custom surface design workflows and high-throughput analyses in a highly cost-effective manner.

Early Perturbations in Red Blood Cells in Response to Murine Malarial Parasite Infection: Proof-of-Concept 1H NMR Metabolomic Study

BACKGROUND

The major focus of metabolomics research has been confined to the readily available biofluids-urine and blood serum. However, red blood cells (RBCs) are also readily available, and may be a source of a wealth of information on vertebrates. However, the comprehensive metabolomic characterization of RBCs is minimal although they exhibit perturbations in various physiological states. RBCs act as the host of malarial parasites during the symptomatic stage. Thus, understanding the changes in RBC metabolism during infection is crucial for a better understanding of disease progression.

METHODS

The metabolome of normal RBCs obtained from Swiss mice was investigated using 1H NMR spectroscopy. Several 1 and 2-dimensional 1H NMR experiments were employed for this purpose. The information from this study was used to investigate the changes in the RBC metabolome during the early stage of infection (~1% infected RBCs) by Plasmodium bergheii ANKA.

RESULTS

We identified over 40 metabolites in RBCs. Several of these metabolites were quantitated using 1H NMR spectroscopy. The results indicate changes in the choline/membrane components and other metabolites during the early stage of malaria.

CONCLUSIONS

The paper reports the comprehensive characterization of the metabolome of mouse RBCs. Changes during the early stage of malarial infection suggest significant metabolic alteration, even at low parasite content (~1%).

GENERAL SIGNIFICANCE

This study should be of use in maximizing the amount of information available from metabolomic experiments on the cellular components of blood. The technique can be directly applied to real-time investigation of infectious diseases that target RBCs.

Deep Phenotyping of the Lipidomic Response in COVID and non-COVID Sepsis

Lipids may influence cellular penetrance by pathogens and the immune response that they evoke. Here we find a broad based lipidomic storm driven predominantly by secretory (s) phospholipase A 2 (sPLA 2 ) dependent eicosanoid production occurs in patients with sepsis of viral and bacterial origin and relates to disease severity in COVID-19. Elevations in the cyclooxygenase (COX) products of arachidonic acid (AA), PGD 2 and PGI 2 , and the AA lipoxygenase (LOX) product, 12-HETE, and a reduction in the high abundance lipids, ChoE 18:3, LPC-O-16:0 and PC-O-30:0 exhibit relative specificity for COVID-19 amongst such patients, correlate with the inflammatory response and link to disease severity. Linoleic acid (LA) binds directly to SARS-CoV-2 and both LA and its di-HOME products reflect disease severity in COVID-19. AA and LA metabolites and LPC-O-16:0 linked variably to the immune response. These studies yield prognostic biomarkers and therapeutic targets for patients with sepsis, including COVID-19. An interactive purpose built interactive network analysis tool was developed, allowing the community to interrogate connections across these multiomic data and generate novel hypotheses.

Sexual dimorphism in the response to chronic circadian misalignment on a high-fat diet

Longitudinal studies associate shiftwork with cardiometabolic disorders but do not establish causation or elucidate mechanisms of disease. We developed a mouse model based on shiftwork schedules to study circadian misalignment in both sexes. Behavioral and transcriptional rhythmicity were preserved in female mice despite exposure to misalignment. Females were protected from the cardiometabolic impact of circadian misalignment on a high-fat diet seen in males. The liver transcriptome and proteome revealed discordant pathway perturbations between the sexes. Tissue-level changes were accompanied by gut microbiome dysbiosis only in male mice, biasing toward increased potential for diabetogenic branched chain amino acid production. Antibiotic ablation of the gut microbiota diminished the impact of misalignment. In the United Kingdom Biobank, females showed stronger circadian rhythmicity in activity and a lower incidence of metabolic syndrome than males among job-matched shiftworkers. Thus, we show that female mice are more resilient than males to chronic circadian misalignment and that these differences are conserved in humans.

Attaining freshwater and estuarine-water soil saturation in an ecosystem-scale coastal flooding experiment

Coastal upland forests are facing widespread mortality as sea-level rise accelerates and precipitation and storm regimes change. The loss of coastal forests has significant implications for the coastal carbon cycle; yet, predicting mortality likelihood is difficult due to our limited understanding of disturbance impacts on coastal forests. The manipulative, ecosystem-scale Terrestrial Ecosystem Manipulation to Probe the Effects of Storm Treatments (TEMPEST) experiment addresses the potential for freshwater and estuarine-water disturbance events to alter tree function, species composition, and ecosystem processes in a deciduous coastal forest in MD, USA. The experiment uses a large-unit (2000 m²), un-replicated experimental design, with three 50 m × 40 m plots serving as control, freshwater, and estuarine-water treatments. Transient saturation (5 h) of the entire soil rooting zone (0-30 cm) across a 2000 m² coastal forest was attained by delivering 300 m³ of water through a spatially distributed irrigation network at a rate just above the soil infiltration rate. Our water delivery approach also elevated the water table (typically ~ 2 m belowground) and achieved extensive, low-level inundation (~ 8 cm standing water). A TEMPEST simulation approximated a 15-cm rainfall event and based on historic records, was of comparable intensity to a 10-year storm for the area. This characterization was supported by showing that Hurricane Ida's (~ 5 cm rainfall) hydrologic impacts were shorter (40% lower duration) and less expansive (80% less coverage) than those generated through experimental manipulation. Future work will apply TEMPEST treatments to evaluate coastal forest resilience to changing hydrologic disturbance regimes and identify conditions that initiate ecosystem state transitions.

Coexistent diabetes is associated with the presence of adverse phenotypic features in patients with hypertrophic cardiomyopathy

Background

Type 2 diabetes mellitus (DM) is associated with worsened clinical outcomes in hypertrophic cardiomyopathy (HCM) patients. The reasons for this adverse prognostic association are incompletely understood. Although distinct entities both HCM and DM share common features of impaired myocardial energetics and coronary microvascular function.

Purpose

We sought to test the hypothesis that co-existent diabetes is associated with greater reductions in myocardial energetics and perfusion, and higher scar burden in HCM.

Research design and methods

Seventy-five age- and sex-matched participants with concomitant HCM and DM (HCM-DM, n=20), isolated HCM (n=20), isolated DM (n=20) and healthy volunteers (HV, n=15) underwent 31phosphorus magnetic resonance spectroscopy and cardiovascular magnetic resonance imaging. The HCM groups were matched for HCM phenotype. The DM groups were matched for diabetes treatment, duration, HbA1c, body mass index and hypertension comorbidity.

Results

ESC sudden cardiac death risk scores were comparable between the HCM groups (HCM: 2.2±1.5%, HCM-DM: 1.9±1.2%; p=NS) and sarcomeric mutations were equally common. HCM-DM had the highest NT-proBNP levels (HV: 42 ng/L [IQR: 35–66], DM: 118 ng/L [IQR: 53–187], HCM: 298 ng/L [IQR: 157–837], HCM-DM: 726 ng/L [IQR: 213–8695]; p<0.0001). Left-ventricular ejection fraction, mass and wall thickness were similar between the HCM groups. HCM-DM displayed a greater degree of fibrosis burden with higher scar percentage, and lower global longitudinal strain compared to the isolated HCM. PCr/ATP was similarly decreased in the HCM-DM and DM (HV: 2.17±0.49, DM: 1.61±0.23, HCM: 1.93±0.38, HCM-DM: 1.54±0.27; p=0.0003). HCM-DM had the lowest stress myocardial blood flow (HV: 2.06±0.42 ml/min/g, DM: 1.78±0.45 ml/min/g, HCM: 1.74±0.44 ml/min/g, HCM-DM: 1.39±0.42 ml/min/g; p=0.004).

Conclusions

We show for the first time that HCM patients with DM comorbidity display greater reductions in myocardial energetics, perfusion, contractile function and higher myocardial scar burden and serum NT-proBNP levels compared to patients with isolated HCM despite similar LV mass and wall thickness and presence of sarcomeric mutations. These adverse phenotypic features may be important components of the adverse clinical manifestation attributable to a combined presence of HCM and DM.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): Diabetes UK

Influence of sex on cardiovascular outcomes in RBM20 variant carriers

Background

Variants in the RBM20 gene cause dilated cardiomyopathy and may be associated with a poor prognosis.

Objectives

To determine disease penetrance, the risk of adverse events and the influence of sex on outcomes in RBM20 variant carriers.

Methods

Consecutive probands and relatives carrying pathogenic or likely pathogenic RBM20 variants were retrospectively recruited from 12 cardiomyopathy units. The primary endpoint was a composite of malignant ventricular arrhythmia (MVA) and end-stage heart failure (ESHF). MVA and ESHF endpoints were also analysed separately and males and females compared.

Results

Longitudinal follow-up data were available for 163 RBM20 variant carriers (82 male, median age 36.5 years, median follow-up 77.6 months). 10/163 had an MVA event at baseline. 30/153 without baseline MVA (19.6%) reached the primary endpoint with a trend towards worse outcomes in males (p=0.08). 16/153 (10.5%) had new MVA with no difference between males and females (p=0.92). 20/163 (12.2%) developed ESHF (17 males and 3 females; p<0.001).

By the end of follow-up, 114 patients (70%) had either left ventricular systolic dysfunction (LVSD) or had experienced MVA. 22 patients received a first diagnosis of LVSD during follow-up. Disease penetrance in individuals over 40 years of age was 78.5% by last evaluation.

Eleven patients that reached the MVA endpoint had a left ventricular ejection fraction (LVEF) available within 6 months of the event. Median [IQR] contemporary LVEF was 30% [23.75, 40%]. 5/11 patients had a contemporary LVEF >35%. 1/11 had a contemporary LVEF >45% (a female, 1st degree relative presenting with sustained ventricular tachycardia and an LVEF of 65%).

Conclusions

RBM20 variants are highly penetrant. The risk of MVA in male and female RBM20 variant carriers is similar but male sex is strongly associated with ESHF. MVA events occur in patients with LVEF >35%.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation Clinical Research Training Fellowship

Abstract 3178: A stromal integrated stress response activates perivascular cancer-associated fibroblasts to drive angiogenesis and tumor progression

Despite recent advances in prevention and treatment, including immune checkpoint inhibitors, malignant melanoma remains a particularly aggressive and deadly malignancy, which is partly attributed to its highly heterogeneous TME. However, malignant cells exhibit altered signaling pathways, which enables them to adapt to both cell-intrinsic and extrinsic stressors within TME. The activating transcription factor 4 (ATF4) is a master transcriptional effector of the Integrated Stress Response (ISR), a homeostatic mechanism coupling cell growth and survival to bioenergetic demands. We and others have established a critical tumor cell-intrinsic role of ATF4 which culminates in the promotion of primary tumor growth and in the establishment of micro- and macro-metastases in xenograft, allograft and transgenic models. However, the potential roles of the ISR and particularly of ATF4-mediated responses in host-dependent, tumor-related processes, have not been yet extensively investigated. Using novel conditional knockout ATF4 mouse models, we show that global loss of host ATF4 results in deficient tumor vascularization and a pronounced tumor growth delay in syngeneic melanoma and pancreatic tumor models. Immunofluorescence analysis revealed a severely impaired angiogenic phenotype in tumors grown in ATF4 KO mice which was accompanied by deficiencies in markers of CAF activation. Single-cell transcriptomic analysis of B16F10 melanoma tumors further localized this defect to a distinct CAF population, previously identified as vascular CAFs (vCAFs), and revealed a significant reduction in the expression of extracellular matrix components, primarily type I collagen, in tumors grown in ATF4 KO mice. Intriguingly, we identified a multifaceted impairment of the collagen biosynthetic pathway with the ATF4 to directly regulate the expression of the Col1a1 gene as well as the intracellular levels of glycine and proline, the major amino acids comprising collagen fibers. Moreover, we showed that the ATF4-deficient vCAFs secrete significantly lower levels of angiogenic factors (i.e., VEGF, SDF-1 etc.) in the perivascular area leading to an abnormal angiogenesis and significant attenuation of tumor growth. Specific deletion of ATF4 in the fibroblast compartment (Col1a1 promoter) produced a similar tumor growth delay as in the global ATF4 KO mice, and notably, co-injection of fibroblasts from ATF4-proficient mice led to significant recovery of tumor growth rates in ATF4-deficient mice. Finally, analysis of human melanoma and pancreatic tumor samples revealed a strong correlation between ATF4 and collagen levels and between an ISR gene signature and expression of collagen and CAF activation genes. Our findings uncover a novel role of stromal ATF4 in shaping CAF functionality, a key driver of disease progression, metastasis, and therapy resistance.

Citation Format: Ioannis I. Verginadis, Harris Avgousti, Kyle Kim, Giorgos Skoufos, Frank Chinga, Nektaria Maria Leli, Ilias V. Karagounis, Brett I. Bell, Anastasia Velalopoulou, Victoria S. Wu, Yang Li, Jiangbin Ye, David A. Scott, Andrei L. Osterman, Arjun Sengupta, Aalim Weljie, Artemis G. Hatzigeorgiou, Sandra Ryeom, Alan J. Diehl, Serge Y. Fuchs, Ellen Puré, Constantinos Koumenis. A stromal integrated stress response activates perivascular cancer-associated fibroblasts to drive angiogenesis and tumor progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3178.

0426 Shallower sleep depth in the laboratory is not related to insomnia severity

Introduction

In insomnia, classical sleep scoring parameters are often uncorrelated with symptom severity and may not fully capture more subtle alterations in the polysomnogram (PSG) that could contribute to clinical symptoms. The odds ratio product (ORP) is a well-validated, continuous index of sleep depth (range 0=deep sleep; 2.5=full wakefulness) that offers an alternative to traditional staging. It is unknown whether ORP is related to self-reported insomnia severity. We hypothesized that individuals with insomnia would exhibit higher ORP values than healthy controls (reflecting less deep sleep) which would be associated with greater insomnia severity.

Methods

This is a secondary analysis of data from a study in which n=15 participants with chronic insomnia disorder and n=15 age- and sex-matched healthy controls completed an in-laboratory protocol (N=30; 66% female; 36±8 years; 63% White). Participants had their sleep monitored with in-lab PSG. The Insomnia Severity Index (ISI) was used to estimate sleep disturbance severity. PSG were used to calculate classical sleep scoring parameters as well as the average ORP in each sleep stage. Independent samples t-tests compared means between the insomnia and healthy control groups and Pearson’s correlations assessed relations between PSG/ORP outcome measures and ISI scores.

Results

The insomnia group’s mean (SD) ISI score was 14.13 (6.00) and significantly higher than the control group’s (1.73 (2.37); corrected p < 0.001). There were no statistically significant between-group differences for classically-scored sleep parameters or average ORP values after correcting for multiple comparisons. Interestingly, means for the insomnia group’s average ORP values tended to be higher than those of the control group’s. ISI scores were not significantly associated with average ORP values across or within groups.

Conclusion

Insomnia does not appear to be associated with alterations in global sleep depth when measured in a laboratory setting, but there is a need to conduct more detailed analyses on patterns across the night.

Support (If Any)

Merck, Inc. Investigator Studies Program

The cancellation heuristic in intertemporal choice shifts people's time preferences

Building on past research in risky decision making, the present research investigated whether the cancellation heuristic is evident in intertemporal choice. Specifically, the cancellation heuristic posits that whenever choice options are partitioned into multiple components, people ignore seemingly identical components and compare the non-identical components. We nudged people to employ the cancellation heuristic by partitioning both the smaller earlier reward and the larger later reward into a seemingly identical component and a non-identical component. Given diminishing marginal utility, we hypothesized that people would perceive an identical difference between the smaller earlier reward and the larger later reward as being subjectively greater when both amounts are smaller in magnitude, thereby increasing the relative attractiveness of the larger later reward in the partition condition. We conducted four studies, including two incentive-compatible lab experiments, one incentive-compatible lab-in-the-field experiment, and one survey study using choices among both gains and losses. We consistently found that this choice architecture intervention significantly increased people's likelihood of choosing the larger later reward. Furthermore, we provide evidence of the underlying mechanism-people's intertemporal decisions shifted to a greater extent in the cancellation condition, particularly if their marginal utility diminished faster. The findings indicate that two features of human psychology-diminishing marginal utility and the cancellation heuristic-can be simultaneously utilized to nudge people to make decisions that would be better for them in the long run.

Optimization of external (in air) particle induced gamma-ray emission (PIGE) methodology for rapid, non-destructive, and simultaneous quantification of fluorine, sodium, and phosphorus in nuclear waste immobilization matrices

External (in air) PIGE methodology has been optimized for rapid quantification of fluorine, sodium, and phosphorus in fluorapatite waste immobilization matrices for Molten Salt Reactor (MSR).

Effect of Nanoparticle Synthetic Conditions on Ligand Coating Integrity and Subsequent Nano-Biointeractions

Most current nanoparticle formulations have relatively low clearance efficiency, which may hamper their likelihood for clinical translation. Herein, we sought to compare the clearance and cellular distribution profiles between sub-5 nm, renally-excretable silver sulfide nanoparticles (Ag₂S-NPs) synthesized via either a bulk, high temperature, or a microfluidic, room temperature approach. We found that the thermolysis approach led to significant ligand degradation, but the surface coating shell was unaffected by the microfluidic synthesis. We demonstrated that the clearance was improved for Ag₂S-NPs with intact ligands, with less uptake in the liver. Moreover, differential distribution in hepatic cells was observed, where Ag₂S-NPs with degraded coatings tend to accumulate in Kupffer cells and those with intact coatings are more frequently found in hepatocytes. Therefore, understanding the impact of synthetic processes on ligand integrity and subsequent nano-biointeractions will aid in designing nanoparticle platforms with enhanced clearance and desired distribution profiles.

Treatment of Insomnia with Zaleplon in HIV+ Significantly Improves Sleep and Depression

More than 50% of individuals who are HIV positive report insomnia, which can reduce HIV treatment adherence, impair quality of life, and contribute to metabolic dysfunction. Major depressive disorder is also highly comorbid in this population, leading to further impairment. There is evidence that treating insomnia may improve not only sleep, but depression and metabolic function, as well. The present study aimed to examine the effects of pharmacotherapeutic treatment of insomnia on sleep, depression, and metabolic functioning in individuals with HIV. 20 individuals with asymptomatic seropositive HIV and comorbid insomnia and depression were administered zaleplon for 6 weeks. Insomnia severity was assessed using the Insomnia Severity Index and Epworth Sleepiness Scale, and depression severity was assessed using the Quick Inventory of Depression, both prior to treatment and 6 weeks post treatment. Metabolomic changes were assessed using a comprehensive platform measuring ~2000 lipid features and polar metabolites. Linear mixed effects models demonstrated that 6 weeks of treatment with zaleplon significantly improved symptoms of both insomnia and depression. Metabolomic analyses also demonstrated that changes in insomnia severity were associated with significant changes in key branched chain amino acid metabolites. Our results show that improvement in insomnia is associated with reduced depressive symptoms and beneficial metabolomic changes. Additionally, changes in key branched chain amino acid metabolites following treatment may serve as useful biomarkers of treatment response.

Detrimental immediate and long-term clinical effects of right ventricular pacing in patients with myocardial fibrosis

Funding Acknowledgements

Type of funding sources: None.

Background

Long-term right ventricular (RV) pacing leads to heart failure or a decline in left ventricular (LV) function in up to a fifth of patients.

Objectives

We aimed to establish whether patients with focal fibrosis detected on late gadolinium enhancement cardiovascular magnetic resonance (CMR) have deterioration in LV function after RV pacing.

Methods

We recruited 110 patients (84 in final analysis) into two observational CMR studies. Patients (n = 34) with a dual chamber device and preserved atrioventricular (AV) conduction underwent CMR in two asynchronous pacing modes (AOO & DOO) to compare intrinsic conduction with RV pacing. Patients (n = 50) with high-grade AV block underwent CMR before and 6 months after pacemaker implantation to investigate the long-term effects of RV pacing.

Results: The three key findings were

1) Initiation of RV pacing in patients with fibrosis, compared to those without, was associated with greater immediate changes in both LV end-systolic volume index (LVESVi) (5.3 ± 3.5 vs 2.1 ± 2.4 mL/m2; p < 0.01) and LV ejection fraction (LVEF) (-5.7 ± 3.4% vs -3.2 ± 2.6%; p = 0.02); 2) Long-term RV pacing in patients with fibrosis, compared to those without, was associated with greater changes in LVESVi (8.0 ± 10.4 vs -0.6 ± 7.3 mL/m2; p = 0.008) and LVEF (-12.3 ± 7.9 vs -6.7 ± 6.2%; p = 0.012); 3) Patients with fibrosis did not experience an improvement in quality of life, biomarkers or functional class after pacemaker implantation.

Conclusions

Fibrosis detected on CMR is associated with immediate and long-term deterioration in LV function following RV pacing and could be used to identify those at risk of heart failure prior to pacemaker implantation.

Characteristics before and after pacing Study 1 No fibrosis (n = 16) Fibrosis (n = 18) AOO DOO p-value AOO DOO p-value LVEDVi - mL/m² 66 ± 13 66 ± 12 0.67 78 ± 14 79 ± 13 0.34 LVESVi - mL/m² 30 ± 10 32 ± 9 0.003 38 ± 11 43 ± 12 <0.001 LVEF - % 56 ± 6 53 ± 5 <0.001 52 ± 8 47 ± 9 <0.001 Mechanical Dyssynchrony index - ms 61 ± 17 71 ± 25 0.07 81 ± 18 89 ± 21 0.04 Study 2 No fibrosis (n = 19) Fibrosis (n = 31) Pre-PPM Post-PPM p-value Pre-PPM Post-PPM p-value LVEDVi -mL/m² 88 ± 21 73 ± 14 <0.001 90 ± 18 83 ± 21 0.007 LVESVi -mL/m² 35 ± 9 34 ± 9 0.71 41 ± 14 49 ± 21 0.001 LVEF - % 60 ± 5 54 ± 7 <0.001 56 ± 8 43 ± 12 <0.001 Mechanical Dyssynchrony index - ms 70 ± 29 81 ± 22 0.15 84 ± 30 98 ± 31 0.03 Abstract Figure. Mechanism for heart failure after pacing

Tinnitus: A Tingling Mystery to be Decrypted

Tinnitus is a hearing disorder that causes ringing, buzzing or hissing sensation to the patient’s auditory senses. It has become a very common complaint over the years affecting around 7-8% of the human population all over the world. The disorder causes the patients to feel irritable, annoyed, depressed, and distressed. As a result, it obstructs their sense of relaxation, enjoyment, and even their sleep - thus forcing them to avoid any social gatherings. There has been a substantial amount of work that has been carried out pertinent to this disorder. This paper reviews existing research and work done regarding Tinnitus effects, causes, and diagnosis. The numerous ways in which Tinnitus could affect an individual have been depicted. From the plethora of probable causes of this disorder, the most conceivable ones are highlighted. Moreover, this paper documents and reviews the attempts at treating Tinnitus, relevant engineering breakthroughs, and the various ways in which Tinnitus noise is suppressed – such as Tinnitus Retraining Therapy, Neuromodulation, and Signal processing approach. The manuscripts highlight the pros and cons of these methods. Over 45 research articles and other reliable internet medical sources were reviewed and these pieces of work were contrasted. These findings should help in understanding both – the disorder, as well as the situation of the patients suffering from it. Through this manuscript, an attempt was made to spread awareness about the mysterious disorder.

0054 Metabolite Profiles of Obstructive Sleep Apnea Distinguishes Cases from Controls and Improve With CPAP

Introduction

Obstructive sleep apnea (OSA) is a common sleep breathing disorder with significant public health consequences. Despite this, no clinically available objective molecular biomarkers to diagnose, risk stratify and quantify treatment efficiency exist. To this end, high-throughput metabolomics data could serve as a valuable quantitative tool.

Methods

We designed a pilot study to investigate the metabolomic effects of OSA and CPAP treatment. Blood serum samples were collected from OSA patients and healthy controls matched with respect to age (±5 years), BMI (±2.5 kg/m2) and gender (N = 20/group). Samples from OSA patients were obtained before and after continuous positive airway pressure (CPAP) treatment. Polar metabolites were analyzed using a targeted ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) metabolomics technique.

Results

Supervised multivariate analysis using serum metabolic values of OSA patients and healthy controls showed a significantly different overall metabolic profile between the two groups (orthogonal partial least squares discriminant analysis [OPLS-DA] Q2=0.25, p=0.04). Acetylornithine, choline, cytidine, dodecenoylcarnitine, methionine sulfoxide and 3-indoxylsulfate were among the most perturbed metabolites. Major metabolic pathways altered in the OSA patients were methionine and phospholipid metabolism, as well as gut microbial co-metabolism. Lysophosphatidylcholine (16:0), a phospholipid metabolite, demonstrated significant linear association with improved oxygen saturation nadir post CPAP treatment (R2 = 0.57), suggesting the metabolic features may be used as prognostic clinical biomarkers.

Conclusion

These results suggest that OSA significantly impacts blood metabolites, which could potentially be used to establish OSA biomarkers. Moreover, specific metabolic features are associated with post CPAP improvement, such as phospholipids, suggesting a functional association of these metabolites that may help us understand the heterogeneity of OSA. Overall, these results demonstrate the potential of metabolic profiling to develop quantitative molecular markers of OSA. Further studies are underway to validate these findings and investigate the utility of metabolic profiles to objectively measure CPAP efficacy.

Support

The work was supported by the program project grant P01 HL094307.

0346 Metabolic Aging and Sleep Loss: Metabolite Signatures Link Sleep Deprivation and Aging Across Tissues

Introduction

Insufficient sleep is a hallmark of modern society, and sleep deprivation (SD) is a risk factor for neurodegenerative and cardiometabolic disorders. The interactions of aging with systemic and local metabolic alterations induced by sleep deprivation are essentially unexplored. In this study, we demonstrate a shared metabolic imprint of SD and aging in plasma, liver, and hippocampus.

Methods

Young (2 - 4 months) and aged (22 - 24 months) mice were sleep deprived (N = 10/group) for 5 hours followed by collection of blood plasma, liver and hippocampus. The samples were extracted and subjected to UPLC-MS/MS based targeted metabolomics analysis.

Results

Young animals displayed greater sensitivity to SD induced metabolic changes with >40% more metabolites perturbed in each sample type measured compared to aged animals. Enrichment analysis based on known disease-associated metabolites suggests that plasma change in young animals are of pathological relevance, but not in aged animals. A common hepatic signature of sleep-loss across the two age groups consisted of ketosis and urea cycle perturbation. Approximately 20-30% of measured metabolites exhibit similar changes when the sleep deprivation induced signature is compared with the aging metabolic imprint in a tissue-dependent manner. Central energetics, urea cycle and aromatic amino acid metabolism highlight the common pathways altered by sleep and aging in the periphery. In the hippocampus, choline and acetylcholine pools were depleted, potentially providing insight into the changes in metabolism that accompany analogous defects in memory consolidation.

Conclusion

These results support the notion that SD makes the ‘young seem old’. The results further connect neurobehavioral observations tying together aging and sleep loss, by implicating molecular mechanisms at the level of metabolism.

Support

This work was supported by NIH grant R21AG052905 (AMW, AS), P50AG017628 (TA; A.I. Pack, PI) and R01AG062398 (TA, JT). TA was supported by the Brush Family Chair in Biology at Penn and is currently supported by the Roy J. Carver Chair of Neuroscience at Iowa.

Reduced Global Efficiency and Random Network Features in Patients with Relapsing-Remitting Multiple Sclerosis with Cognitive Impairment

BACKGROUND AND PURPOSE

Graph theory uses structural similarity to analyze cortical structural connectivity. We used a voxel-based definition of cortical covariance networks to quantify and assess the relationship of network characteristics to cognition in a cohort of patients with relapsing-remitting MS with and without cognitive impairment.

MATERIALS AND METHODS

We compared subject-specific structural gray matter network properties of 18 healthy controls, 25 patients with MS with cognitive impairment, and 55 patients with MS without cognitive impairment. Network parameters were compared, and predictive value for cognition was assessed, adjusting for confounders (sex, education, gray matter volume, network size and degree, and T1 and T2 lesion load). Backward stepwise multivariable regression quantified predictive factors for 5 neurocognitive domain test scores.

RESULTS

Greater path length (r = -0.28, P < .0057) and lower normalized path length (r = 0.36, P < .0004) demonstrated a correlation with average cognition when comparing healthy controls with patients with MS. Similarly, MS with cognitive impairment demonstrated a correlation between lower normalized path length (r = 0.40, P < .001) and reduced average cognition. Increased normalized path length was associated with better performance for processing (P < .001), learning (P < .001), and executive domain function (P = .0235), while reduced path length was associated with better executive (P = .0031) and visual domains. Normalized path length improved prediction for processing (R ² = 43.6%, G² = 20.9; P < .0001) and learning (R ² = 40.4%, G² = 26.1; P < .0001) over a null model comprising confounders. Similarly, higher normalized path length improved prediction of average z scores (G² = 21.3; P < .0001) and, combined with WM volume, explained 52% of average cognition variance.

CONCLUSIONS

Patients with MS and cognitive impairment demonstrate more random network features and reduced global efficiency, impacting multiple cognitive domains. A model of normalized path length with normal-appearing white matter volume improved average cognitive z score prediction, explaining 52% of variance.

Metabolism of sleep and aging: Bridging the gap using metabolomics

Sleep is a conserved behavior across the evolutionary timescale. Almost all known animal species demonstrate sleep or sleep like states. Despite extensive study, the mechanistic aspects of sleep need are not very well characterized. Sleep appears to be needed to generate resources that are utilized during the active stage/wakefulness as well as clearance of waste products that accumulate during wakefulness. From a metabolic perspective, this means sleep is crucial for anabolic activities. Decrease in anabolism and build-up of harmful catabolic waste products is also a hallmark of aging processes. Through this lens, sleep and aging processes are remarkably parallel- for example behavioral studies demonstrate an interaction between sleep and aging. Changes in sleep behavior affect neurocognitive phenotypes important in aging such as learning and memory, although the underlying connections are largely unknown. Here we draw inspiration from the similar metabolic effects of sleep and aging and posit that large scale metabolic phenotyping, commonly known as metabolomics, can shed light to interleaving effects of sleep, aging and progression of diseases related to aging. In this review, data from recent sleep and aging literature using metabolomics as principal molecular phenotyping methods is collated and compared. The present data suggests that metabolic effects of aging and sleep also demonstrate similarities, particularly in lipid metabolism and amino acid metabolism. Some of these changes also overlap with metabolomic data available from clinical studies of Alzheimer's disease. Together, metabolomic technologies show promise in elucidating interleaving effects of sleep, aging and progression of aging disorders at a molecular level.

Diagnostic efficacy of cone beam computed tomography in paediatric dentistry: a systematic review

Purpose

To determine in which clinical situations it is indicated or contra-indicated to prescribe cone beam computed tomography (CBCT) for paediatric patients.

Methods

Systematic review of in vivo paediatric research studies of diagnostic efficacy using CBCT, with supplementary searches for guideline documents on CBCT and for systematic reviews permitting inclusion of ex vivo and adult studies.

Results

After screening, 190 publications were included, mostly case studies. No systematic reviews were found of in vivo paediatric research. Fourteen studies of diagnostic efficacy were identified. The supplementary searches found 18 guideline documents relevant to the review and 26 systematic reviews. The diagnostic efficacy evidence on CBCT was diverse and often of limited quality. There was ex vivo evidence for diagnostic accuracy being greater using CBCT than radiographs for root fractures. The multiplanar capabilities of CBCT are advantageous when localising dental structures for surgical planning. Patient movement during scanning is more common in children which could reduce diagnostic efficacy.

Conclusions

No strong recommendations on CBCT are possible, except that it should not be used as a primary diagnostic tool for caries. Guidelines on use of CBCT in the paediatric age group should be developed cautiously, taking into account the greater radiation risk and the higher economic costs compared with radiography. CBCT should only be used when adequate conventional radiographic examination has not answered the question for which imaging was required. Clinical research in paediatric patients is required at the higher levels of diagnostic efficacy of CBCT.

Electronic supplementary material

The online version of this article (10.1007/s40368-019-00504-x) contains supplementary material, which is available to authorized users.

NMR Spectroscopy-Based Metabolic Profiling of Biospecimens

Metabolomics refers to study of metabolites in biospecimens such as blood serum, tissues, and urine. Nuclear magnetic resonance (NMR) spectroscopy and ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS; mass spectrometry coupled with liquid chromatography) are most frequently employed to analyze complex biological/clinical samples. NMR is a relatively insensitive tool compared to UPLC-MS/MS but offers straightforward quantification and identification and easy sample processing. One-dimensional ¹ H NMR spectroscopy is inherently quantitative and can be readily used for metabolite quantification without individual metabolite standards. Two-dimensional spectroscopy is most commonly used for identification of metabolites but can also be used quantitatively. Although NMR experiments are unbiased regarding the chemical nature of the analyte, it is crucial to adhere to the proper metabolite extraction protocol for optimum results. Selection and implementation of appropriate NMR pulse programs are also important. Finally, employment of the correct metabolite quantification strategy is crucial as well. In this unit, step-by-step guidance for running an NMR metabolomics experiment from typical biospecimens is presented. The unit describes an optimized metabolite extraction protocol, followed by implementation of NMR experiments and quantification strategies using the so-called "targeted profiling" technique. This approach relies on an underlying basis set of metabolite spectra acquired under similar conditions. Some strategies for statistical analysis of the data are also presented. Overall, this set of protocols should serve as a guide for anyone who wishes to enter the world of NMR-based metabolomics analysis. © 2019 by John Wiley & Sons, Inc. Basic Protocol 1: Metabolite extraction from different biospecimens Basic Protocol 2: Preparation of dried upper fraction for NMR analysis Alternate Protocol: Preparation of urine samples for NMR analysis Basic Protocol 3: NMR experiments Basic Protocol 4: Spectral processing and quantification of metabolites Basic Protocol 5: Statistical analysis of the data.

Real-world Effectiveness and Safety of Vedolizumab for the Treatment of Inflammatory Bowel Disease: The Scottish Vedolizumab Cohort

BACKGROUND & AIMS

Vedolizumab is an anti-a4b7 monoclonal antibody that is licensed for the treatment of moderate to severe Crohn's disease and ulcerative colitis. The aims of this study were to establish the real-world effectiveness and safety of vedolizumab for the treatment of inflammatory bowel disease.

METHODS

This was a retrospective study involving seven NHS health boards in Scotland between June 2015 and November 2017. Inclusion criteria included: a diagnosis of ulcerative colitis or Crohn's disease with objective evidence of active inflammation at baseline (Harvey-Bradshaw Index[HBI] ≥5/Partial Mayo ≥2 plus C-reactive protein [CRP] >5 mg/L or faecal calprotectin ≥250 µg/g or inflammation on endoscopy/magnetic resonance imaging [MRI]); completion of induction; and at least one clinical follow-up by 12 months. Kaplan-Meier survival analysis was used to establish 12-month cumulative rates of clinical remission, mucosal healing, and deep remission [clinical remission plus mucosal healing]. Rates of serious adverse events were described quantitatively.

RESULTS

Our cohort consisted of 180 patients with ulcerative colitis and 260 with Crohn's disease. Combined median follow-up was 52 weeks (interquartile range [IQR] 26-52 weeks). In ulcerative colitis, 12-month cumulative rates of clinical remission, mucosal healing, and deep remission were 57.4%, 47.3%, and 38.5%, respectively. In Crohn's disease, 12-month cumulative rates of clinical remission, mucosal healing, and deep remission were 58.4%, 38.9%, and 28.3% respectively. The serious adverse event rate was 15.6 per 100 patient-years of follow-up.

CONCLUSIONS

Vedolizumab is a safe and effective treatment for achieving both clinical remission and mucosal healing in ulcerative colitis and Crohn's disease.

Altered diurnal states in insomnia reflect peripheral hyperarousal and metabolic desynchrony: a preliminary study

Study Objectives

Insomnia is a common sleep disorder that is associated with a range of adverse outcomes. Patients with insomnia exhibit hyperarousal in multiple domains, including an elevated metabolic rate, but specific metabolic molecular perturbations are unknown. Furthermore, objective clinical markers of insomnia are not available and current assessment of pathological extent relies on self-report. Here, we provide preliminary evidence that chronic insomnia is remarkably reflected in the periphery through detailed metabolic assessments.

Methods

Serum from confirmed patients with insomnia and matched good sleepers (n = 15 per group) was sampled at high temporal resolution (every 2 hr over 48 hr). Food intake was controlled by providing hourly isocaloric snacks, and sleep architecture was assessed by overnight polysomnography. Quantitative metabolic assessments were conducted using nuclear magnetic resonance spectroscopy.

Results

Global metabolic profiles differentiated patients with insomnia from healthy controls, with elevated amino acid and energy metabolites and reduced branched-chain amino acid catabolic products. Strikingly, branched-chain amino acid catabolism was found to be specifically altered during the night with ~10 per cent increased accumulation of glucose in insomnia patients. Rhythmicity analysis revealed 11 metabolites that cycled diurnally across both groups, with phase advances noted for acetone and delays for lactate and branched-chain amino acids and their products.

Conclusions

These preliminary observations suggest that insomnia is associated with quantitative metabolic dysregulation and supports the hyperarousal hypothesis. Furthermore, we posit that these changes lead to a state of metabolic desynchrony in insomnia that is involved in the pathophysiology of the disorder and/or mediates its impact on health outcomes.

Clinical Trials Registration

NCT01957111.

AN EXPERIMENTAL ANALYSIS AND VALIDATION OF ELECTRICAL IMPEDANCE TOMOGRAPHY TECHNIQUE FOR MEDICAL OR INDUSTRIAL APPLICATION

Electrical impedance tomography is a recently established technique by which impedance of an object (medical or nonmedical applications) is measured data from the surface of the object, and a numerically simulated reconstruction of the object internal shape of the image can be obtained. This imaging technique based on boundary or surface voltage is measured when the different current pattern is injected into it. For current pulse, we are creating a voltage controlled current source, which is based on the different RC circuits, according to current amplitude and frequency values. The current source used in inject the current pulse of the various phantoms. The current position and measuring voltage is controlled by the created control unit or programmable system on chip (PSOC) of the proposed EIT system. After that image reconstruction of the cross-sectional image of resistivity requires sufficient data collection from used phantoms, which is based on finite element method (FEM) method and Tikhonov regularization method with helps of graphical user interface (GUI) on MatLab. The objective of the GUI was to produce an image (2D/3D), impedance distribution graph, and the FEM mesh model according to used electrode combinations from the various phantoms. EIT system has a great potential for imaging modality, is non-invasive, radiation-free, and inexpensive for medical applications.

Metabolomic changes in vertebrate host during malaria disease progression

Metabolomics refers to top-down systems biological analysis of metabolites in biological specimens. Phenotypic proximity of metabolites makes them interesting candidates for studying biomarkers of environmental stressors such as parasitic infections. Moreover, the host-parasite interaction directly impinges upon metabolic pathways since the parasite uses the host metabolite pool as a biosynthetic resource. Malarial infection, although not recognized as a classic metabolic disorder, often leads to severe metabolic changes such as hypoglycemia and lactic acidosis. Thus, metabolomic analysis of the infection has become an invaluable tool for promoting a better understanding of the host-parasite interaction and for the development of novel therapeutics. In this review, we summarize the current knowledge obtained from metabolomic studies of malarial infection in rodent models and human patients. Metabolomic analysis of experimental rodent malaria has provided significant insights into the mechanisms of disease progression including utilization of host resources by the parasite, sexual dimorphism in metabolic phenotypes, and cellular changes in host metabolism. Moreover, these studies also provide proof of concept for prediction of cerebral malaria. On the other hand, metabolite analysis of patient biofluids generates extensive data that could be of use in identifying biomarkers of infection severity and in monitoring disease progression. Through the use of metabolomic datasets one hopes to assess crucial infection-specific issues such as clinical severity, drug resistance, therapeutic targets, and biomarkers. Also discussed are nascent or newly emerging areas of metabolomics such as pre-erythrocytic stages of the infection and the host immune response. This review is organized in four broad sections-methodologies for metabolomic analysis, rodent infection models, studies of human clinical specimens, and potential of immunometabolomics. Data summarized in this review should serve as a springboard for novel hypothesis testing and lead to a better understanding of malarial infection and parasite biology.

Imaging of pure spin-valley diffusion current in WS2-WSe2 heterostructures

Transition metal dichalcogenide (TMDC) materials are promising for spintronic and valleytronic applications because valley-polarized excitations can be generated and manipulated with circularly polarized photons and the valley and spin degrees of freedom are locked by strong spin-orbital interactions. In this study we demonstrate efficient generation of a pure and locked spin-valley diffusion current in tungsten disulfide (WS₂)-tungsten diselenide (WSe₂) heterostructures without any driving electric field. We imaged the propagation of valley current in real time and space by pump-probe spectroscopy. The valley current in the heterostructures can live for more than 20 microseconds and propagate over 20 micrometers; both the lifetime and the diffusion length can be controlled through electrostatic gating. The high-efficiency and electric-field-free generation of a locked spin-valley current in TMDC heterostructures holds promise for applications in spin and valley devices.

ATP-Citrate Lyase Controls a Glucose-to-Acetate Metabolic Switch

Mechanisms of metabolic flexibility enable cells to survive under stressful conditions and can thwart therapeutic responses. Acetyl-coenzyme A (CoA) plays central roles in energy production, lipid metabolism, and epigenomic modifications. Here, we show that, upon genetic deletion of Acly, the gene coding for ATP-citrate lyase (ACLY), cells remain viable and proliferate, although at an impaired rate. In the absence of ACLY, cells upregulate ACSS2 and utilize exogenous acetate to provide acetyl-CoA for de novo lipogenesis (DNL) and histone acetylation. A physiological level of acetate is sufficient for cell viability and abundant acetyl-CoA production, although histone acetylation levels remain low in ACLY-deficient cells unless supplemented with high levels of acetate. ACLY-deficient adipocytes accumulate lipid in vivo, exhibit increased acetyl-CoA and malonyl-CoA production from acetate, and display some differences in fatty acid content and synthesis. Together, these data indicate that engagement of acetate metabolism is a crucial, although partial, mechanism of compensation for ACLY deficiency.

SOFAST-HMQC-an efficient tool for metabolomics

Nuclear magnetic resonance (NMR)-based metabolomics relies mostly on 1D NMR; however, the technique is limited by overlap of the signals from the metabolites. In order to circumvent this problem, 2D ¹H-¹³C correlation spectroscopy techniques are often used. However owing to poorer natural abundance and gyromagnetic ratio of ¹³C, the acquisition time for 2D ¹H-¹³C heteronuclear single quantum coherence spectroscopy (HSQC) is long. This makes it almost impossible to be used in high throughput study. We have reported the application of selective optimized flip angle short transient (SOFAST) technique coupled to heteronuclear multiple quantum correlation (HMQC) along with nonlinear sampling (NUS) in urine and serum samples. This technique takes sevenfold less experimental time than the conventional ¹H-¹³C HSQC experiment with retention of almost all molecular information. Hence, this can be used for high throughput study. Graphical abstract SOFAST-HMQC is a two-dimensional NMR technique that significantly decreases experimental time without loss of information. This technique is applied in complex biofluid samples that are used for high throughput metabolomics studies and shows promise of better information recovery than conventional two-dimensional NMR technique in shorter time.

Host metabolic responses to Plasmodium falciparum infections evaluated by 1H NMR metabolomics

The human malarial parasite Plasmodium falciparum causes the most severe forms of malarial infections, which include cerebral malaria and various organ dysfunctions amongst adults in India. So far no dependable clinical descriptor is available that can distinguish cerebral malaria from other symptomatically similar diseases such as sepsis and encephalitis. This study aims at evaluating the differential metabolic features of plasma samples from P. falciparum patients with varying severities, and patients suffering from symptomatically similar diseases. ¹H Nuclear Magnetic Resonance (NMR) based metabolic profiling of the plasma of the infected individuals and the control population was performed. The differences in the plasma profiles were evaluated through multivariate statistical analyses. The results suggest malaria-specific elevation of plasma lipoproteins. Such an increase was absent in control populations. In addition, cerebral malaria patients exhibited a decrease in plasma glycoproteins; such a reduction was not observed in malarial patients without cerebral symptoms. The data presented here indicates that the metabolism and/or transport of the plasma lipids is specifically perturbed by malarial infections. The differential perturbation of the plasma glycoprotein levels in cerebral malaria patients may have important implications in the diagnosis of cerebral malaria.

Efficacy and Safety of Mycobacterium indicus pranii as an adjunct therapy in Category II pulmonary tuberculosis in a randomized trial

Prolonged treatment of tuberculosis (TB) often leads to poor compliance, default and relapse, converting primary TB patients into category II TB (Cat IITB) cases, many of whom may convert to multi-drug resistant TB (MDR-TB). We have evaluated the immunotherapeutic potential of Mycobacterium indicus pranii (MIP) as an adjunct to Anti-Tubercular Treatment (ATT) in Cat II pulmonary TB (PTB) patients in a prospective, randomized, double blind, placebo controlled, multicentric clinical trial. 890 sputum smear positive Cat II PTB patients were randomized to receive either six intra-dermal injections (2 + 4) of heat-killed MIP at a dose of 5 × 10⁸ bacilli or placebo once in 2 weeks for 2 months. Sputum smear and culture examinations were performed at different time points. MIP was safe with no adverse effects. While sputum smear conversion did not show any statistically significant difference, significantly higher number of patients (67.1%) in the MIP group achieved sputum culture conversion at fourth week compared to the placebo (57%) group (p = 0.0002), suggesting a role of MIP in clearance of the bacilli. Since live bacteria are the major contributors for sustained incidence of TB, the potential of MIP in clearance of the bacilli has far reaching implications in controlling the spread of the disease.