Autophagy Modulation and Its Implications on Glioblastoma Treatment.

Autophagy is a vital cellular process that functions to degrade and recycle damaged organelles into basic metabolites. This allows a cell to adapt to a diverse range of challenging conditions. Autophagy assists in maintaining homeostasis, and it is tightly regulated by the cell. The disruption of autophagy has been associated with many diseases, such as neurodegenerative disorders and cancer. This review will center its discussion on providing an in-depth analysis of the current molecular understanding of autophagy and its relevance to brain tumors. We will delve into the current literature regarding the role of autophagy in glioma pathogenesis by exploring the major pathways of JAK2/STAT3 and PI3K/AKT/mTOR and summarizing the current therapeutic interventions and strategies for glioma treatment. These treatments will be evaluated on their potential for autophagy induction and the challenges associated with their utilization. By understanding the mechanism of autophagy, clinical applications for future therapeutics in treating gliomas can be better targeted.

Perianal Fistulas Are Associated with Persistently Higher Direct Health Care Costs in Crohn's Disease: A Population-Based Study.

BACKGROUND: The economic impact of perianal fistulas in Crohn's disease (CD) has not been formally assessed in population-based studies in the biologic era. AIM: To compare direct health care costs in persons with and without perianal fistulas. METHODS: We performed a longitudinal population-based study using administrative data from Ontario, Canada. Adults (> 17 years) with CD were identified between 2007 and 2013 using validated algorithms. Perianal fistula positive "cases" were matched to up to 4 "controls" with CD without perianal fistulas based on age, sex, geographic region, year of CD diagnosis and duration of follow-up. Direct health care costs, excluding drug costs from private payers, were estimated annually beginning 5 years before (lookback) and up to 9 years after perianal fistula diagnosis (study completion) for cases and a standardized date for matched controls. RESULTS: A total of 581 cases were matched to 1902 controls. The annual per capita direct cost for cases was similar at lookback compared to controls ($2458 ± 6770 vs $2502 ± 10,752; p = 0.952), maximally greater in the first year after perianal fistulas diagnosis ($16,032 ± 21,101 vs $6646 ± 13,021; p < 0.001) and remained greater at study completion ($11,358 ± 17,151 vs $5178 ± 9792; p < 0.001). At perianal fistula diagnosis, the cost difference was driven primarily by home care cost (tenfold greater), publicly-covered prescription drugs (threefold greater) and hospitalizations (twofold greater), whereas at study completion, prescription drugs were the dominant driver (threefold greater). CONCLUSION: In our population-based cohort, perianal fistulas were associated with significantly higher direct healthcare costs at the time of perianal fistulas diagnosis and sustained long-term.

MXene-Supported, Atomic-Layered Iridium Catalysts Created by Nanoparticle Re-Dispersion for Efficient Alkaline Hydrogen Evolution.

Tailoring the structure of metal components and interaction with their anchored substrates is essential for improving the catalytic performance of supported metal catalysts; the ideal catalytic configuration, especially down to the range of atomic layers, clusters, and even single atoms, remains a subject under intensive study. Here, an Ir-on-MXene (Mo2 TiC2 Tx ) catalyst with controlled morphology changing from nanoparticles down to flattened atomic layers, and finally ultrathin layers and single atoms dispersed on MXene nanosheets at elevated temperature, is presented. The intermediate structure, consisting of mostly Ir atomic layers, shows the highest activity toward the hydrogen evolution reaction (HER) under industry-compatible alkaline conditions. In addition, the better HER activity of Ir atomic layers than that of single atoms suggests that the former serves as the main active sites. Detailed mechanism analysis reveals that the nanoparticle re-dispersion process and Ir atomic layers with a moderate interaction to the substrate associate with unconventional electron transfer from MXene to Ir, leading to suitable H* adsorption. The results indicate that the structural design is important for the development of highly efficient catalysts.

Fluoroscopy-Guided High-Intensity Focused Ultrasound Neurotomy of the Lumbar Zygapophyseal Joints: A Clinical Pilot Study.

OBJECTIVE: To investigate the safety and feasibility of a fluoroscopy-guided, high-intensity focused ultrasound system for zygapophyseal joint denervation as a treatment for chronic low back pain. METHODS: The clinical pilot study was performed on 10 participants diagnosed with lumbar zygapophyseal joint syndrome. Each participant had a documented positive response to a diagnostic block or a previous, clinically beneficial radiofrequency ablation. For a descriptive study, the primary outcome was the safety question. All device- or procedure-related adverse events were collected. Secondary outcome variables included the average numeric rating scale for pain, the Roland-Morris Disability Questionnaire, the Brief Pain Inventory, the Patient Global Impression of Change, the morphine equivalent dose, and the finding of the neurological examination. RESULTS: All participants tolerated the procedure well with no significant device- or procedure-related adverse events; there was one episode of transient pain during the procedure. The average numeric rating scale score for pain decreased from 6.2 at baseline to 2.1 (n = 10) after 1 month, 4.9 (n = 9) after 3 months, 3.0 (n = 8) after 6 months, and 3.0 (n = 6) after 12 months. The ratio of participants who were considered a treatment success was 90% at 1 month, 50% at 3 months, 60% at 6 months, and 40% at 12 months. CONCLUSIONS: The first clinical pilot study using a noninvasive, fluoroscopy-guided, high-intensity focused ultrasound lumbar zygapophyseal neurotomy resulted in no significant device- or procedure-related adverse events and achieved clinical success comparable with that of routine radiofrequency ablation.

Hope and fear in the experience of suspense.

The topic of mixed emotions has received considerable attention in recent years. However, two limitations in this research are the lack of (a) theoretical prediction regarding the types of conditions likely to cause one emotion to yield to another, and (b) attention given to the moment-to-moment (MTM) experience of mixed emotions. Using the empirical context of competitive contests, the mixed emotions state of suspense was manipulated in a series of studies designed to address these shortcomings. The results indicate that the most appropriate emotion pair to describe suspense is hope and fear. In addition, we find that the juxtaposition of these two emotions over the temporal sequence relies on viewers' interpretation of observed events relative to a preferred outcome. The results indicate a prevalence of bipolarity between hope and fear at lower levels of suspense and bivariance at higher levels. Given a high-suspense episode, both hope and fear are activated; whereas when suspense is low, hope (fear) is ascendant and fear (hope) declines when it becomes obvious a preferred competitor will ultimately win (lose).

Carbon Nitride-Based Ruthenium Single Atom Photocatalyst for CO2 Reduction to Methanol.

With increasing concerns for global warming, the solar-driven photocatalytic reduction of CO2 into chemical fuels like methanol is a propitious route to enrich energy supplies, with concomitant reduction of the abundant CO2  stockpiles. Herein, a novel single atom-confinement and a strategy are reported toward single ruthenium atoms dispersion over porous carbon nitride surface. Ruthenium single atom character is well confirmed by EXAFS absorption spectrometric analysis unveiling the cationic coordination environment for the single-atomic-site ruthenium center, that is formed by Ru-N/C intercalation in the first coordination shell, attaining synergism in N-Ru-N connection and interfacial carrier transfer. From time resolved fluorescence decay spectra, the average carrier lifetime of the RuSA-mC3 N4 system is found to be higher compared to m-C3 N4 ; the fact uncovering the crucial role of single Ru atoms in promoting photocatalytic reaction system. A high yield of methanol (1500 µmol g-1 cat. after 6 h of the reaction) using water as an electron donor and the reusability of the developed catalyst without any significant change in the efficiency represent the superior aspects for its potential application in real industrial technologies.

Single Co-Atoms as Electrocatalysts for Efficient Hydrazine Oxidation Reaction.

Single-atom catalysts (SACs) have aroused great attention due to their high atom efficiency and unprecedented catalytic properties. A remaining challenge is to anchor the single atoms individually on support materials via strong interactions. Herein, single atom Co sites have been developed on functionalized graphene by taking advantage of the strong interaction between Co2+ ions and the nitrile group of cyanographene. The potential of the material, which is named G(CN)Co, as a SAC is demonstrated using the electrocatalytic hydrazine oxidation reaction (HzOR). The material exhibits excellent catalytic activity for HzOR, driving the reaction with low overpotential and high current density while remaining stable during long reaction times. Thus, this material can be a promising alternative to conventional noble metal-based catalysts that are currently widely used in HzOR-based fuel cells. Density functional theory calculations of the reaction mechanism over the material reveal that the Co(II) sites on G(CN)Co can efficiently interact with hydrazine molecules and promote the NH bond-dissociation steps involved in the HzOR.

Applications of WaterControl to TOCSY and COSY experiments.

WaterControl is a solvent suppression method based on WATERGATE and PGSTE and is very efficient in selectively reducing the solvent signal in 1D pulse-acquire and 2D NOESY of protein solutions. In this study, the WaterControl technique was appended to two common 2D NMR methods used in resonance assignment of proteins, namely TOCSY and CLIP-COSY. Similar to that observed in regular 1D pulse-acquire and 2D NOESY, the incorporation of WaterControl in these 2D methods led to excellent solvent suppression superior to that obtained using W3- or W5-based WATERGATE sequences. The water signal was essentially eliminated in the TOCSY and CLIP-COSY with WaterControl while useful cross peaks around the water resonance at ω2 were preserved. This is in contrast to the 2D spectra obtained from the corresponding WATERGATE containing sequences, where these cross peaks in the ω2 region are usually suppressed together with the water resonance. These new WaterControl sequences provide significantly improved water suppression thereby facilitating protein NMR studies.

Thiol-water proton exchange of glutathione, cysteine, and N-acetylcysteine: Implications for CEST MRI.

Amide-, amine-, and hydroxyl-water proton exchange can generate MRI contrast through chemical exchange saturation transfer (CEST). In this study, we show that thiol-water proton exchange can also generate quantifiable CEST effects under near-physiological conditions (pH = 7.2 and 37°C) through the characterization of the pH dependence of thiol proton exchange in phosphate-buffered solutions of glutathione, cysteine, and N-acetylcysteine. The spontaneous, base-catalyzed, and buffer-catalyzed exchange contributions to the thiol exchange were analyzed. The thiol-water proton exchange of glutathione and cysteine was found to be too fast to generate a CEST effect around neutral pH due to significant base catalysis. The thiol-water proton exchange of N-acetylcysteine was found to be much slower, yet still in the fast-exchange regime with significant base and buffer catalysis, resulting in a 9.5% attenuation of the water signal at pH 7.2 in a slice-selective CEST NMR experiment. Furthermore, the N-acetylcysteine thiol CEST was also detectable in human serum albumin and agarose phantoms.

Diffusion-Limited Formation of Nonequilibrium Intermetallic Nanophase for Selective Dehydrogenation.

Nonequilibrium intermetallic phases in the nanoscale were realized by diffusion-controlled solid-state transformation, forming SiO2 supported NPs with Pd core and a CsCl type Pd1M1 shell, where M is Sn or Sb. The core-shell geometry is identified from scanning transmission electron microscopy and infrared spectroscopy and the crystal structure is confirmed from in situ synchrotron X-ray diffraction and X-ray absorption spectroscopy. The highly symmetric Pd1M1 intermetallic phase has not been reported previously and contains catalytic ensembles with high selectivity toward dehydrogenation of propane. The kinetically limited solid-state reaction is generally applicable to nanoparticle synthesis and could produce materials with desired structures and properties beyond conventional structural limits.

A new phase modulated binomial-like selective-inversion sequence for solvent signal suppression in NMR.

A new 8-pulse Phase Modulated binomial-like selective inversion pulse sequence, dubbed '8PM', was developed by optimizing the nutation and phase angles of the constituent radio-frequency pulses so that the inversion profile resembled a target profile. Suppression profiles were obtained for both the 8PM and W5 based excitation sculpting sequences with equal inter-pulse delays. Significant distortions were observed in both profiles because of the offset effect of the radio frequency pulses. These distortions were successfully reduced by adjusting the inter-pulse delays. With adjusted inter-pulse delays, the 8PM and W5 based excitation sculpting sequences were tested on an aqueous lysozyme solution. The 8 PM based sequence provided higher suppression selectivity than the W5 based sequence. Two-dimensional nuclear Overhauser effect spectroscopy experiments were also performed on the lysozyme sample with 8PM and W5 based water signal suppression. The 8PM based suppression provided a spectrum with significantly increased (~ doubled) cross-peak intensity around the suppressed water resonance compared to the W5 based suppression. Copyright © 2016 John Wiley & Sons, Ltd.

In vivo imaging of microfluidic-produced microbubbles.

Microfluidics-based production of stable microbubbles for ultrasound contrast enhancement or drug/gene delivery allows for precise control over microbubble diameter but at the cost of a low production rate. In situ microfluidic production of microbubbles directly in the vasculature may eliminate the necessity for high microbubble production rates, long stability, or small diameters. Towards this goal, we investigated whether microfluidic-produced microbubbles directly administered into a mouse tail vein could provide sufficient ultrasound contrast. Microbubbles composed of nitrogen gas and stabilized with 3 % bovine serum albumin and 10 % dextrose were injected for 10 seconds into wild type C57BL/6 mice, via a tail-vein catheter. Short-axis images of the right and left ventricle were acquired at 12.5 MHz and image intensity over time was analyzed. Microbubbles were produced on the order of 10(5) microbubbles/s and were observed in both the right and left ventricles. The median rise time, duration, and decay time within the right ventricle were 2.9, 21.3, and 14.3 s, respectively. All mice survived the procedure with no observable respiratory or heart rate distress despite microbubble diameters as large as 19 µm.

MRI Detection of Hepatic N-Acetylcysteine Uptake in Mice.

This proof-of-concept study looked at the feasibility of using a thiol-water proton exchange (i.e., CEST) MRI contrast to detect in vivo hepatic N-acetylcysteine (NAC) uptake. The feasibility of detecting NAC-induced glutathione (GSH) biosynthesis using CEST MRI was also investigated. The detectability of the GSH amide and NAC thiol CEST effect at B0 = 7 T was determined in phantom experiments and simulations. C57BL/6 mice were injected intravenously (IV) with 50 g L-1 NAC in PBS (pH 7) during MRI acquisition. The dynamic magnetisation transfer ratio (MTR) and partial Z-spectral data were generated from the acquisition of measurements of the upfield NAC thiol and downfield GSH amide CEST effects in the liver. The 1H-NMR spectroscopy on aqueous mouse liver extracts, post-NAC-injection, was performed to verify hepatic NAC uptake. The dynamic MTR and partial Z-spectral data revealed a significant attenuation of the mouse liver MR signal when a saturation pulse was applied at -2.7 ppm (i.e., NAC thiol proton resonance) after the IV injection of the NAC solution. The 1H-NMR data revealed the presence of hepatic NAC, which coincided strongly with the increased upfield MTR in the dynamic CEST data, providing strong evidence that hepatic NAC uptake was detected. However, this MTR enhancement was attributed to a combination of NAC thiol CEST and some other upfield MT-generating mechanism(s) to be identified in future studies. The detection of hepatic GSH via its amide CEST MRI contrast was inconclusive based on the current results.

The Androgen Regulated lncRNA NAALADL2-AS2 Promotes Tumor Cell Survival in Prostate Cancer.

Castration resistance is the leading cause of death in men with prostate cancer. Recent studies indicate long noncoding RNAs (lncRNAs) to be important drivers of therapy resistance. The aim of this study was to identify differentially expressed lncRNAs in castration-resistant prostate cancer (CRPC) and to functionally characterize them in vitro. Tumor-derived RNA-sequencing data were used to quantify and compare the expression of 11,469 lncRNAs in benign, primary prostate cancer, and CRPC samples. CRPC-associated lncRNAs were selected for semi-quantitative PCR validation on 68 surgical tumor specimens. In vitro functional studies were performed by antisense-oligonucleotide-mediated lncRNA knockdown in hormone-sensitive prostate cancer (HSPC) and CRPC cell line models. Subsequently, cell proliferation, apoptosis, cell cycle, transcriptome and pathway analyses were performed using the appropriate assays. Transcriptome analysis of a prostate cancer tumor specimens unveiled NAALADL2-AS2 as a novel CRPC-upregulated lncRNA. The expression of NAALADL2-AS2 was found to be particularly high in HSPC in vitro models and to increase under androgen deprived conditions. NAALADL2-AS2 knockdown decreased cell viability and increased caspase activity and apoptotic cells. Cellular fractionization and RNA fluorescent in situ hybridization identified NAALADL2-AS2 as a nuclear transcript. Transcriptome and pathway analyses revealed that NAALADL2-AS2 modulates the expression of genes involved with cell cycle control and glycogen metabolism. We hypothesize that the nuclear lncRNA, NAALADL2-AS2, functions as a pro-survival signal in prostate cancer cells under pressure of targeted hormone therapy.

OxLDL-mediated survival of macrophages does not require LDL internalization or signalling by major pattern recognition receptors.

Macrophages play a key role in the pathogenesis of atherosclerosis, in part by destabilizing plaques. We and others have shown that low concentrations of oxidized LDL (oxLDL) inhibit macrophage apoptosis. As oxLDL is present in lesions, this may be a mechanism by which macrophage populations in the intima are expanded. We have previously shown that oxLDL activates prosurvival signalling pathways such as the phosphoinositide 3-kinase (PI3K) pathway in bone marrow derived macrophages (BMDMs). However, little is known about more upstream signalling events especially at the receptor level. The endocytic pattern recognition receptors (PRRs), scavenger receptor A (SR-A) and CD36, are the main receptors on macrophages for uptake of oxLDL and are therefore important in foam cell formation. The signalling PRRs such as toll-like receptor (TLR) 2 and 4 also bind some types of oxLDL. This study was done to determine if any of the known PRRs are required for the anti-apoptotic effects of oxLDL in BMDMs. To do this, we tested the effect of oxLDL on viability of BMDMs lacking both SR-A and CD36 or lacking TLR2, TLR4, CD14, FcγRIIb, or RAGE. Our results indicate that none of these receptors are essential for activating the oxLDL prosurvival pathway. Furthermore, we show that the anti-apoptotic effect is not dependent on the uptake of oxLDL.

Tolerability and Feasibility of X-ray Guided Non-Invasive Ablation of the Medial Branch Nerve with Focused Ultrasound: Preliminary Proof of Concept in a Pre-clinical Model.

Four to six million patients a year in the United States suffer from chronic pain caused by facet joint degeneration. Thermal ablation of the affected facet joint's sensory nerve using radiofrequency electrodes is the therapeutic standard of care. High-intensity focused ultrasound (HIFU) is a novel technology enabling image-guided non-invasive thermal ablation of tissue. Six pigs underwent fluoroscopy-guided HIFU of the medial branch nerve and were followed up for 1 wk (two pigs), 1 mo (two pigs) and 3 mo (two pigs). At the end of each follow-up period, the animals were sacrificed, and targeted tissue was excised and evaluated with computed tomography scans as well as by macro- and micropathology. No significant adverse events were recorded during the procedure or follow-up period. All targets were successfully ablated. X-Ray-guided HIFU is a feasible and promising alternative to radiofrequency ablation of the lumbar facet joint sensory nerve.

Onset of High Methane Combustion Rates over Supported Palladium Catalysts: From Isolated Pd Cations to PdO Nanoparticles.

Industrial low-temperature methane combustion catalyst Pd/Al2O3 suffers from H2O-induced deactivation. It is imperative to design Pd catalysts free from this deactivation and with high atomic efficiency. Using a small-pore zeolite SSZ-13 as support, herein we report well-defined Pd catalysts with dominant active species as finely dispersed Pd cations, uniform PdO particles embedded inside the zeolite framework, or PdO particles decorating the zeolite external surface. Through detailed reaction kinetics and spectroscopic and microscopic studies, we show that finely dispersed sites are much less active than PdO nanoparticles. We further demonstrate that H2O-induced deactivation can be readily circumvented by using zeolite supports with high Si/Al ratios. Finally, we provide a few rational catalyst design suggestions for methane oxidation based on the new knowledge learned in this study.

Sphingosine kinase regulates oxidized low density lipoprotein-mediated calcium oscillations and macrophage survival.

We recently reported that oxidized LDL (oxLDL) induces an oscillatory increase in intracellular calcium ([Ca(2+)](i)) levels in macrophages. Furthermore, we have shown that these [Ca(2+)](i) oscillations mediate oxLDL's ability to inhibit macrophage apoptosis in response to growth factor deprivation. However, the signal transduction pathways by which oxLDL induces [Ca(2+)](i) oscillations have not been elucidated. In this study, we show that these oscillations are mediated in part by intracellular mechanisms, as depleting extracellular Ca(2+) did not completely abolish the effect. Inhibiting sarco-endoplasmic reticulum ATPase (SERCA) completely blocked [Ca(2+)](i) oscillations, suggesting a role for Ca(2+) reuptake by the ER. The addition of oxLDL resulted in an almost immediate activation of sphingosine kinase (SK), which can increase sphingosine-1-phosphate (S1P) levels by phosphorylating sphingosine. Moreover, S1P was shown to be as effective as oxLDL in blocking macrophage apoptosis and producing [Ca(2+)](i) oscillations. This suggests that the mechanism in which oxLDL generates [Ca(2+)](i) oscillations may be 1) activation of SK, 2) SK-mediated increase in S1P levels, 3) S1P-mediated Ca(2+) release from intracellular stores, and 4) SERCA-mediated Ca(2+) reuptake back into the ER.

Oxidized LDL-mediated macrophage survival involves elongation factor-2 kinase.

OBJECTIVE: Macrophage survival and proliferation is believed to be a contributing factor in the development of early atherosclerotic lesions. Oxidized low density lipoprotein (oxLDL), a key mediator in the pathogenesis of this disease, has been shown to block apoptosis in macrophages deprived of growth factor. In this report, we investigate the mechanism of oxLDL-mediated macrophage survival. METHODS AND RESULTS: OxLDL, but not native LDL (nLDL), induces an immediate and oscillatory increase in intracellular calcium ([Ca(2+)](i)). We also show that the calcium/calmodulin dependent kinase, eukaryotic elongation factor-2 kinase (eEF2 kinase), is activated in response to oxLDL, an effect that can be blocked by inhibiting calcium mobilization. Furthermore, selective inhibition of eEF2 kinase reverses the prosurvival effect of oxLDL and results in cellular apoptosis. p38 MAP kinase, a negative regulator of eEF2 kinase, is activated on growth factor withdrawal, a response that can be inhibited by oxLDL. Finally, we show that oxLDL, by activating eEF2 kinase, phosphorylates and therefore inhibits eEF2, resulting in an overall decrease in protein synthesis. CONCLUSIONS: These results indicate a novel signaling pathway in which oxLDL can block macrophage apoptosis by mobilizing calcium and activating eEF2 kinase.

LOX-1 augments oxLDL uptake by lysoPC-stimulated murine macrophages but is not required for oxLDL clearance from plasma.

Oxidized LDL (oxLDL) promotes lipid accumulation as well as growth and survival signaling in macrophages. OxLDL uptake is mainly due to scavenger receptors SR-AI/II and CD36. However, other scavenger receptors such as lectin-like oxLDL receptor-1 (LOX-1) may also play a role. We used mice with targeted inactivation of the LOX-1 gene to define the role of this receptor in the uptake of oxLDL and in activation of survival pathways. There was no difference in uptake or degradation of 125I-oxLDL in unstimulated macrophages from wild-type and LOX-1 knockout mice and no difference in the rate of clearance of oxLDL from plasma in vivo. However, when expression of LOX-1 was induced with lysophosphatidylcholine, oxLDL uptake and degradation increased 2-fold in wild-type macrophages but did not change in LOX-1 knockout macrophages. Macrophages lacking LOX-1 showed the same stimulation of PKB phosphorylation and enhancement of survival by oxLDL as wild-type cells. These data show that LOX-1 does not alter the uptake of oxLDL in unstimulated macrophages and is not essential for the pro-survival effect of oxLDL in these cells. However, LOX-1 expression is highly inducible by lysophosphatidylcholine and pro-inflammatory cytokines, and if that occurred in macrophages within atheromas, LOX-1 could substantially increase oxLDL uptake by lesion macrophages.