Substrate Depletion Research Articles

Graham Wood. 6 February 1934—4 November 2016

Graham Wood was a world-leading corrosion scientist who bridged both the aqueous (electrochemical) corrosion and high-temperature oxidation branches of the subject. His analytical predictions of depletion and enrichment profiles in substrate and scale during preferential oxidation have long been confirmed in practice. He also demonstrated that transient oxides can be vital solid lubricants in oxidative friction and wear processes. He elucidated ionic transport in amorphous anodic films, leading to precise models of pore initiation, development and closure, thus allowing the strict design of anodic films for practical application. He set up, and headed, the Corrosion and Protection Centre at the University of Manchester Institute of Science and Technology (UMIST) and was instrumental in initiating the Corrosion and Protection Centre Industrial Service, which, respectively, became the world's largest academic centre on the study of materials degradation and the world's largest corrosion consulting organization. While keeping active in research, he held increasingly senior administrative roles, where he established a specialist graduate school and helped prepare UMIST to full independence from the Victoria University of Manchester.

Early oral nutritional supplementation with a tgf-β2 enriched formula for Covid-19 patients: a new possible strategy to modulate inflammation?

Rationale: During COVID-19 infection substrate depletion and catabolism occur; SARS-COV 2, acting on intestinal permeability and microbiota balance, leads to pro-inflammatory cytokines production up to cytokine storm. Deregulated immune response and gastrointestinal clinical symptoms resemble IBD in their manifestation. In the evidence for a gut-lung axis, where gut barrier integrity plays a major role in adapting and regulating the immune response, aim of this on-going multicentric study is to investigate efficacy and safety of a specific nutritional formula enriched in TGF-β2, in fighting malnutrition and reducing systemic inflammation.

CC-92480 Enhances Cell-Autonomous Cytotoxicity through Blockade of G 2/M Transition When Combined with Bortezomib/Dexamethasone in Pre-Clinical Multiple Myeloma

Background: Pomalidomide (POM) is an established agent in relapsed/refractory (R/R) multiple myeloma (MM). CC-92480, a novel cereblon E3 ligase modulator (CELMoD ®) agent, is being investigated in R/R MM patients in combination with the proteasome inhibitor (PI) bortezomib (BTZ) and steroid dexamethasone (DEX) (NCT03374085/NCT03989414). Previously, we showed mechanistic synergy of POM/BTZ/DEX in MM cell line models (Bjorklund et al). Here we analyzed the cell autonomous cytotoxic activities of CC-92480 or POM alone and in combination with BTZ/DEX to compare and differentiate their mechanisms of action (MOA).Results:Comparative analysis of the anti-proliferative activity against H929 and MM1.S cell lines revealed that CC-92480 demonstrated a more potent inhibition of proliferation by 100-fold lower dose compared to POM. Combination experiments utilizing a titration of POM or CC-92480 in combination with a 1 hr BTZ pulse, to mimic the clinical pharmacokinetics (+/- DEX co-treatment) showed an enhancement of antiproliferative capacity in both doublet and triplet combinations compared to single agents. Combination indices for POM/BTZ/DEX or CC-92480/BTZ/DEX resulted in values <1 for most combinations indicating a synergistic effect. Additionally, POM or CC-92480 in combination with BTZ or DEX, or in triplet combinations increased induction of apoptosis (>90% for each triplet compared to POM (20%) and CC-92480 (40%). Flow cytometric analysis of Aiolos and Ikaros protein level in MM cells treated with POM/BTZ/DEX or CC-92480/BTZ/DEX resulted in a slight kinetic delay in substrate depletion at early time points (1-4 hr), where the effect is less apparent with CC-92480, and indistinguishable at 24 hr compared to single agent POM or CC-92480 in the clinically relevant concentrations.We performed transcriptomic analyses of H929 cells treated with POM/BTZ/DEX or CC-92480/BTZ/DEX for 24 hrs to identify key pathways responsible for the observed synergistic combination effect. Common pathways dysregulated by POM or CC-92480 included previously identified interferon, protein homeostasis and proliferation gene sets. Gene set enrichment analysis (GSEA) showed many significant pathway differences when comparing the triplets, including general cell cycle progression, cell division and chromatin segregation. Interestingly, genes involved in negative regulation of G 2/M transition were identified as one of the most significant differences between POM/BTZ/DEX and CC-92480/BTZ/DEX.To understand how these pathways contributed to cell cycle effects and apoptosis, we assessed DNA fragmentation by TUNEL in conjunction with cell cycle flow cytometry to examine cell cycle specific apoptotic induction. Temporal assessment (6, 12, 18, 24, and 48 hr treatments) demonstrated accumulation of BrdU incorporation in all cell cycle phases when treated with POM/BTZ/DEX or CC-92480/BTZ/DEX indicating cell death was occurring within all phases. However, there was a marked enhancement of G 2/M BrdU incorporation (80% vs. 40% of G 2/M population) at 18-24 hr when treated with CC-92480/BTZ/DEX compared to POM/BTZ/DEX, or other single agent treatments. Additionally, G 2/M transition-dependent cyclins A and B were shown to be dysregulated by CC-92480. These data indicate that CC-92480 potentiates a G 2/M arrest in combination with BTZ in MM cells.Conclusions: These results demonstrate that CC-92480 alone or in combination with BTZ/DEX elicits a more potent cytotoxic effect on MM cells compared to POM. Importantly, the combination of either POM or CC-92480 with a PI, like BTZ, does not appreciatively affect single agent MOA. We have also identified a key differentiating mechanism of cell autonomous activity for CC-92480 in combination with BTZ/DEX where MM cells enhance apoptotic induction at the G 2/M stage compared to POM. Clinically, this added mechanistic difference suggests a more cytotoxic response in patients treated with CC-92480/BTZ/DEX compared to POM/BTZ/DEX. DisclosuresBjorklund: BMS: Current Employment, Current equity holder in publicly-traded company. Amatangelo: Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company. Kang: BMS: Current equity holder in publicly-traded company. Chiu: Bristol Myers Squibb: Current Employment, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company. Pourdehnad: Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company, Patents & Royalties: No royalty. Hagner: BMS: Current Employment, Current equity holder in publicly-traded company. Thakurta: Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company.

Pre-Clinical and Clinical Immunomodulatory Effects of Pomalidomide or CC-92480 in Combination with Bortezomib in Multiple Myeloma

▪Background: Pomalidomide (POM) is an established agent in relapsed/refractory (R/R) multiple myeloma (MM) with direct cytotoxicity against MM cells and immunostimulatory activities in multiple cell types including T cells and NK cells. CC-92480 is a novel Aiolos/Ikaros degrading cereblon E3 ligase modulator (CELMoD ®) agent is currently being investigated in combination with the proteasome inhibitor (PI) bortezomib (BTZ) and corticosteroid dexamethasone (DEX), or with DEX only in R/R MM (CC-92480-MM-002 and CC-92480-MM-001). Previous results indicate that triplet combination of POM/BTZ/DEX may enhance some T, B and NK cell subpopulations, overcoming immunosuppression when compared to BTZ/DEX-only treated patients (Rao et al, 2019). Mechanisms of action (MOA) of CC-92480- and POM-mediated substrate depletion occurs via ubiquitination and proteasome degradation, where BTZ has been speculated as potentially antagonistic as a PI. Here, we report pre-clinical and clinical observations of an immune MOA of CC-92480 or POM in combination with BTZ.Results: To mimic the clinical pharmacokinetics, BTZ was utilized as a high-dose pulse method alone and in combination with POM or CC-92480, followed by flow cytometric measurements of Aiolos and Ikaros protein abundance in healthy donor (HD) T cells. The addition of BTZ modestly delayed CRBN-dependent substrate depletion compared to single agent POM or CC-92480; however, this effect was only apparent at early time points (1-6 hr) where the effect was negligible by 24 hr.To understand the functional implications of BTZ combination, we conducted CD3-stimulated PBMC-mediated cytotoxicity assay against H929 MM target cells in a co-culture model. The efficiency of POM or CC-92480 induced PBMC-mediated killing in a dose dependent manner (~65% increase compared to DMSO) were similar at a 100-fold lower dose range of CC-92480 compared to POM, with the effect not being altered by co-treatment with BTZ. These data were replicated with a POM or CC-92480 treated supernatant stimulation of purified NK cells co-culture, which induced an 80% reduction in target cell viability with the BTZ combination having no negative effects on CELMoD-mediated activity. Cytokine analysis on PBMC supernatants treated with either POM or CC-92480 in the absence or presence of BTZ-pulse showed a dose-dependent increase in IL-2 (>2.4-fold) and Granzyme B (>3.1-fold), which were not impacted by BTZ co-treatment.As a secondary readout on activation status, we measured multiple signaling molecules and activation markers on the cell surface of T and NK cell subsets in CD3 stimulated HD PBMCs treated with dose-dependent POM or CC-92480 with or without co-treatment of BTZ. Compared to DMSO controls, elevated expression levels of CD25 (IL2RA), CD278 (ICOS), Granzyme B, CD134 (OX40R) and HLA-DR were observed with both POM and CC-92480 on CD4, CD8 and NK cells demonstrating a CELMoD-mediated increase in immune activation. These effects were not impacted by the co-treatment of BTZ.Examination of peripheral blood samples from MM patients enrolled in the CC-92480-MM-001/002 (NCT03374085/NCT03989414) clinical trials revealed that CC-92480 promoted potent immunomodulation when administered in combination with DEX and with BTZ/DEX. These data included increased numbers of activated and central memory T cells, as well as increased Ki67+ proliferating T and NK cell populations compared to samples collected during the screening period before any drugs had been administered, consistent with earlier observation of POM in combination with BTZ/DEX treated patients.Conclusions: Taken together, these data demonstrate that POM and CC-92480 are potent immunomodulatory agents with enhanced induction of PBMC and NK mediated cell killing of MM tumor cells and activation of T and NK cells, at 100-fold lower concentrations of CC-92480 compared to POM. Additionally, we showed that combination with BTZ in preclinical assays and in the clinical setting did not antagonistically affect the immunostimulatory ability of POM or CC-92480. DisclosuresBjorklund: BMS: Current Employment, Current equity holder in publicly-traded company. Amatangelo: Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company. Chiu: Bristol Myers Squibb: Current Employment, Current holder of individual stocks in a privately-held company, Current holder of stock options in a privately-held company. Kang: BMS: Current equity holder in publicly-traded company. Civardi: Bristol Myers Squibb: Current Employment. Katz: Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company. Maciag: Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company. Hagner: BMS: Current Employment, Current equity holder in publicly-traded company. Pourdehnad: Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company, Patents & Royalties: No royalty. Bahlis: Pfizer: Consultancy, Honoraria; Amgen: Consultancy, Honoraria; Genentech: Consultancy; BMS/Celgene: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Abbvie: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; GlaxoSmithKline: Consultancy, Honoraria; Sanofi: Consultancy, Honoraria; Karyopharm: Consultancy, Honoraria. Richardson: Oncopeptides: Consultancy, Research Funding; Celgene/BMS: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; Karyopharm: Consultancy, Research Funding; Protocol Intelligence: Consultancy; Janssen: Consultancy; Sanofi: Consultancy; Secura Bio: Consultancy; GlaxoSmithKline: Consultancy; Regeneron: Consultancy; AstraZeneca: Consultancy; AbbVie: Consultancy; Jazz Pharmaceuticals: Consultancy, Research Funding. Thakurta: Bristol Myers Squibb: Current Employment, Current equity holder in publicly-traded company, Patents & Royalties.

Pulseless Electrical Activity: Echocardiographic Explanation of a Perplexing Phenomenon.

Pulseless electrical activity (PEA) is considered an enigmatic phenomenon in resuscitation research and practice. Finding individuals with no consciousness or pulse but with continued electrocardiographic (EKG) complexes obviously raises the question of how they got there. The development of monitors that can display the underlying rhythm has allowed us to differentiate between VF, asystole, and PEA. Lack of clear understanding of the emergence of PEA has limited the research and development of interventions that might improve the low rates of survival typically associated with PEA. Over 30 years of studying and practicing resuscitation have allowed the authors to see a substantial rise in PEA with variable survival rates, based on the patients' illness spectrum and intensity of monitoring. This paper presents a small case series of individuals with brain death whose family members consented to the echocardiographic observation of the dying process after disconnection from life support. The observation from these cases confirms that PEA is a late phase in the clinical dying process. Echocardiographic images delineate the stages of pseudo-PEA with ineffective contractions, PEA, and then asystole. The process is contiuous with none of the sudden phase shifts seen in dysrhythmic events such as VF, VT or SVT. The implications of these findings are that PEA is a common manifestation of tissue hypoxia and metabolic substrate depletion. Our findings offer prospects for studies of the development of interventions to improve PEA survival.

Short-Term Effect of Nitrogen Fertilization on Carbon Mineralization during Corn Residue Decomposition in Soil

The effect of N fertilization on residue decomposition has been studied extensively; however, contrasting results reflect differences in residue quality, the form of N applied, and the type of soil studied. A 60 d laboratory incubation experiment was conducted to ascertain the effect of synthetic N addition on the decomposition of two corn (Zea mays L.) stover mixtures differing in C:N ratio by continuous monitoring of CO2 emissions and periodic measurement of microbial biomass and enzyme activities involved in C and N cycling. Cumulative CO2 production was greater for the high than low N residue treatment, and was significantly increased by the addition of exogenous N. The latter effect was prominent during the first month of incubation, whereas N-treated soils produced less CO2 in the second month, as would be expected due to more rapid substrate depletion from microbial C utilization previously enhanced by greater N availability. The stimulatory effect of exogenous N was verified with respect to active biomass, microbial biomass C and N, and cellulase and protease activities, all of which were significantly correlated with cumulative CO2 production. Intensive N fertilization in modern corn production increases the input of residues but is not conducive to soil C sequestration.

Adaptation of Pseudomonas helmanticensis to fat hydrolysates and SDS: fatty acid response and aggregate formation.

An essential part of designing any biotechnological process is examination of the physiological state of producer cells in different phases of cultivation. The main marker of a bacterial cell's state is its fatty acid (FA) profile, reflecting membrane lipid composition. Consideration of FA composition enables assessment of bacterial responses to cultivation conditions and helps biotechnologists understand the most significant factors impacting cellular metabolism. In this work, soil SDS-degrading Pseudomonas helmanticensis was studied at the fatty acid profile level, including analysis of rearrangement between planktonic and aggregated forms. The set of substrates included fat hydrolysates, SDS, and their mixtures with glucose. Such media are useful in bioplastic production since they can help incrementally lower overall costs. Conventional gas chromatography-mass spectrometry was used for FA analysis. Acridine orange-stained aggregates were observed by epifluorescence microscopy. The bacterium was shown to change fatty acid composition in the presence of hydrolyzed fats or SDS. These changes seem to be driven by the depletion of metabolizable substrates in the culture medium. Cell aggregation has also been found to be a defense strategy, particularly with anionic surfactant (SDS) exposure. It was shown that simple fluidity indices (such as saturated/unsaturated FA ratios) do not always sufficiently characterize a cell's physiological state, and morphological examination is essential in cases where complex carbon sources are used.

Both Acidic pH Value and Binding Interactions of Tartaric Acid With α-Glucosidase Cause the Enzyme Inhibition: The Mechanism in α-Glucosidase Inhibition of Four Caffeic and Tartaric Acid Derivates.

The inhibition mechanism of four caffeic and tartaric acid derivates, including caffeic acid (CA), tartaric acid (TA), caftaric acid (CFA) and chicoric acid (CHA) against α-glucosidase was characterized by substrate depletion, fluorescence quenching, isothermal titration calorimetry (ITC) and molecular docking. TA and CA were found with the highest and no inhibition effect respectively, and caffeoyl substitution at 2 and/or 3-OH of TA significantly decreased its inhibition. The enzyme inhibition effects of organic acids were not in an inhibitor concentration-dependent mode, and there was a rush increase in inhibition at a respective acidic pH value, especially for CFA and CHA, suggesting the important role of acidic pH in the enzyme inhibition for both compounds. Besides, CA, CFA and CHA were shown with strong quenching effects on α-glucosidase fluorescence because of π-conjugations between aromatic ring of caffeoyl moiety and that of enzyme fluorescent residues. However, no fluorescence quenching effect was observed for TA due to lack of aromatic ring. Additionally, a direct binding interaction behavior was observed for TA with α-glucosidase according to the fitted independent binding model in ITC, but not for CFA and CHA. Therefore, both acidic pH and binding interactions of TA with α-glucosidase resulted in the enzyme inhibition.

Is there Evidence for the Suggestion that Fatigue Accumulates Following Resistance Exercise?

It has been suggested that improper post-exercise recovery or improper sequence of training may result in an 'accumulation' of fatigue. Despite this suggestion, there is a lack of clarity regarding which physiological mechanisms may be proposed to contribute to fatigue accumulation. The present paper explores the time course of the changes in various fatigue-related measures in order to understand how they may accumulate or lessen over time following an exercise bout or in the context of an exercise program. Regarding peripheral fatigue, the depletion of energy substrates and accumulation of metabolic byproducts has been demonstrated to occur following an acute bout of resistance training; however, peripheral accumulation and depletion appear unlikely candidates to accumulate over time. A number of mechanisms may contribute to the development of central fatigue, postulating the need for prolonged periods of recovery; however, a time course is difficult to determine and is dependent on which measurement is examined. In addition, it has not been demonstrated that central fatigue measures accumulate over time. A potential candidate that may be interpreted as accumulated fatigue is muscle damage, which shares similar characteristics (i.e., prolonged strength loss). Due to the delayed appearance of muscle damage, it may be interpreted as accumulated fatigue. Overall, evidence for the presence of fatigue accumulation with resistance training is equivocal, making it difficult to draw the conclusion that fatigue accumulates. Considerable work remains as to whether fatigue can accumulate over time. Future studies are warranted to elucidate potential mechanisms underlying the concept of fatigue accumulation.

In vitro assessments predict that CYP3A4 contributes to a greater extent than CYP3A5 to prednisolone clearance.

Because several steroid hormones are metabolized to their respective 6β-hydroxy forms by CYP3A4 and CYP3A5, these isoenzymes have been assumed to metabolize the immunosuppressive drug prednisolone, with conflicting results in the literature with respect to their relative importance. A direct study of the metabolism of prednisolone by microsomal CYP3A4 and CYP3A5 is missing. The aim of this in vitro study was to investigate the relative importance of recombinant CYP3A4 and recombinant CYP3A5 in the metabolism of prednisolone and to compare the extent of formation of 6β-OH-prednisolone by the two enzymes. Through in vitro incubations using rCYP3A4 and rCYP3A5 enzymes, intrinsic clearance (CLint ) of prednisolone was determined by the substrate depletion approach. Formation of the metabolite 6β-OH-prednisolone by rCYP3A4 and rCYP3A5, respectively, was compared. Prednisolone concentrations were measured, and its metabolite 6β-OH-prednisolone was identified using a HPLC-MS/MS in-house method. CLint for prednisolone by rCYP3A5 was less than 26% relative to rCYP3A4. Formation of 6β-OH-prednisolone by rCYP3A5 was less than 11% relative to rCYP3A4. The study indicates that 6β-hydroxylation of prednisolone assessed in vitro in recombinant CYP enzymes depends on rCYP3A4 rather than rCYP3A5 and that CYP3A5 may be responsible for the formation of other prednisolone metabolite(s) in addition to 6β-OH-prednisolone.

Biotransformation Potential of Cationic Surfactants in Fish Assessed with Rainbow Trout Liver S9 Fractions.

Biotransformation may substantially reduce the extent to which organic environmental contaminants accumulate in fish. Presently, however, relatively little is known regarding the biotransformation of ionized chemicals, including cationic surfactants, in aquatic organisms. To address this deficiency, a rainbow trout liver S9 substrate depletion assay (RT‐S9) was used to measure in vitro intrinsic clearance rates (CLint; ml min–1 g liver–1) for 22 cationic surfactants that differ with respect to alkyl chain length and degree of methylation on the charged nitrogen atom. None of the quaternary N,N,N‐trimethylalkylammonium compounds exhibited significant clearance. Rapid clearance was observed for N,N‐dimethylalkylamines, and slower rates of clearance were measured for N‐methylalkylamine analogs. Clearance rates for primary alkylamines were generally close to or below detectable levels. For the N‐methylalkylamines and N,N‐dimethylalkylamines, the highest CLint values were measured for C10–C12 homologs; substantially lower clearance rates were observed for homologs containing shorter or longer carbon chains. Based on its cofactor dependency, biotransformation of C12–N,N‐dimethylamine appears to involve one or more cytochrome P450–dependent reaction pathways, and sulfonation. On a molar basis, N‐demethylation metabolites accounted for up to 25% of the N,N‐dimethylalkylamines removed during the 2‐h assay, and up to 55% of the removed N‐methylalkylamines. These N‐demethylation products possess greater metabolic stability in the RT‐S9 assay than the parent structures from which they derive and may contribute to the overall risk of ionizable alkylamines. The results of these studies provide a set of consistently determined CLint values that may be extrapolated to whole trout to inform in silico bioaccumulation assessments. Environ Toxicol Chem 2021;40:3123–3136. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Competition within low-density bacterial populations as an unexpected factor regulating carbon decomposition in bulk soil

Bacterial decomposition of organic matter in soils is generally believed to be mainly controlled by the access bacteria have to organic substrate. The influence of bacterial traits on this control has, however, received little attention. Using the substrate-dependent Monod growth model, we develop a bioreactive transport model to screen the interactive impacts of spatial dispersion and bacterial traits on mineralization. Bacterial traits primarily involved in the bacterial response to the substrate concentration, such as the maximum specific uptake rate and efficiency, the adaptation time of the uptake rate and the initial population density, are considered. We compare the model results with two sets of previously performed cm-scale soil-core experiments in which the mineralization of the pesticide 2,4-D was measured under well-controlled initial distributions and transport conditions. Bacterial dispersion away from the initial substrate location induced a significant increase in 2,4-D mineralization. It reveals an increase of specific uptake rates at lower bacterial densities, more than compensating the decrease of specific uptake rates caused by substrate dilution. This regulation of bacterial activities by density, caused by the local depletion of substrate by competing bacteria, becomes dominant for bacteria with an efficient uptake of substrate at low substrate concentrations (a common feature of oligotrophs). Such oligotrophs, commonly found in soils, compete with each other for substrate even at remarkably low population densities. The ratio-dependent Contois growth model, which includes a density regulation in the expression of the uptake efficiency, is more accurate and convenient to calibrate than the substrate-dependent Monod model, at least under these conditions. In view of their strong interactions, bioreactive and transport processes cannot be handled independently but should be integrated, in particular when reactive processes of interest are carried out by oligotrophs.

Thickness Modeling of Short-Channel Cylindrical Surrounding Double- Gate MOSFET at Strong Inversion Using Depletion Depth Analysis

Aims: The semiconductor technology has a great impact on consistent growth in the Very-Large- Scale Integrated (VLSI) devices. The transistor size has been scaled down from micron to submicron and towards the nanometer regime in the past 30 years due to technological advancements. The most reliable solid-state device is Metal-Oxide-Semiconductor Field Effect Transistor (MOSFET) but this rapid decrease in the device dimensions with the advent of Moore's law follows several problems, such as Short Channel Effects (SCE's) and Hot Carrier Effects. The channel becomes too small at short channel effects that necessitate the analysis of the optimum device designs, in particular in the operating conditions. The charge-sheet model that can quickly analyze a long-channel device, currently in the subthreshold to saturation regime without any discontinuity, turns out to be inappropriate at reduced channel size. Objectives: At the nano-scaling of the device, since the accumulation layer thickness is comparable to the device, the assumption of the channel as a thin sheet of charge vanishes. Though the depletion layers or zone are the regions of the absentia of charges mostly, the existence affects the device behavior and the channel thickness. Therefore, channel thickness modeling becomes essential at various bias conditions to define the specifics of device operation and the channel dependence of the structural parameters. In this work, the objective is to develop an analytical model and numerical analysis of the Cylindrical Surrounding Double-Gate (CSDG) MOSFET, including the thickness, derived based on the formation of depletion depth to analyze the device performance at reducing dimensions. Methods: The analysis is built upon the device's physical and electrical parameters, such as capacitance, electric field, thickness, threshold voltage, effective channel dimensions, drain current, are considered in this research. The depletion region in a MOSFET structure accounts for the inclusion of the source and drain depletion regions, divided primarily into three separate sub-regions as a junction between the diffused source/drain and the substrate depletion under the channel and by region induced by lateral source and drain diffusion. The condition of a planar MOSFET in channel formation, i.e., for strong inversion, and when VGS &gt; VTH has been considered for this mathematical analysis. Results: The computed results of device thickness and depending parameters for a planar MOSFET and the CSDG MOSFET have been obtained. Based on this analysis, the silicon thickness of the typical CSDG MOSFET computed is 180 nm, 281 nm, and 327 nm at VDS 0.2 V, 0.8 V, and 1.2 V, respectively. The achieved results, through the thickness modeling proposed in this work, show that nanoscale CSDG MOSFET can be deployed for the improvements in the device performance and novel design modifications. Conclusion: The analysis presented in this work significantly contributes to understanding the dependence of semiconductor thickness in CSDG MOSFET and serves as a guide for future modifications in the structure for the device compactness.

Determining the Temperature Dependency of Biodegradation Kinetics for 34 Hydrocarbons while Avoiding Chemical and Microbial Confounding Factors.

Biodegradation kinetics data are keystone for evaluating the environmental persistence and risk of chemicals. Biodegradation kinetics depend highly on the prevailing temperature, which influences microbial community structures, metabolic rates, and chemical availability. There is a lack of high-quality comparative biodegradation kinetics data that are determined at different test temperatures but with the same microbial inoculum and chemical availability. The present study was designed to determine the effect of test temperature on the biodegradation kinetics of hydrocarbons while avoiding confounding factors. We used inocula from a Northern river (2.7 °C) and a Central European river (12.5 °C). Aqueous stock solutions containing 45 individual hydrocarbons were generated by passive dosing and added to river water containing the native microorganisms. Compound-specific biodegradation kinetics were then determined at 2.7, 12, and 20 °C based on substrate depletion. Main findings comprise the following: (1) Degradation half-times (DegT50) of 34 test chemicals were determined at different test temperatures and were largely consistent with the Arrhenius equation (activation energy, 65.4 kJ/mol). (2) Differences in biodegradation kinetics between tested isomers were rather limited. (3) The recent lowering of standard test temperature from 20 to 12 °C results typically in a doubling of DegT50 values and can lead to a stricter persistency assessment.

BIOLOGICAL REQUIREMENTS IN EFFORT AND BODY RECOVERY

Abstract: During physical effort, regardless of its nature, a series of processes take place in the body that can lead to energy consumption that can unbalance homeostasis. After physical effort, the body needs a period of recovery, for the preparation of future physical efforts at optimal parameters and the creation of conditions to increase the capacity of effort, being part of the training process, with a role in creating storage conditions. To help the body be prepared to perform the next physical effort at optimal parameters, it is necessary to apply some means and methods of recovery. Recovery is natural, and can be supplemented and accelerated by guided recovery if the physical effort has led to the depletion of the energy substrate used and there is no time to be restored naturally.

A novel approach to study cellulose digestion kinetics in biogas fermentation applying feed-stop method and artificial medium to investigate effects of saccharides

Anaerobic cellulose digestion kinetics was studied using a novel artificial medium, which allowed cellulose mono-fermentation with a complex biogas biocenosis. Semi-continuous cellulose mono-fermentation was successfully performed with this medium for more than 18 months achieving high organic loading rates of 8.3 gl−1d−1 and short hydraulic residence times of 9.6 days. Cellulose hydrolysis kinetics was studied by monitoring the substrate depletion after short feed-stops using the data obtained to establish a 1st order reaction model. This method was used to assess the cellulose hydrolysis kinetics under the influence of selected carbohydrates, of which a mixture of cellooligosaccharides showed the highest potential. A qPCR-Method was established for quantitative monitoring of selected cellulolytic clostridia based on the extraction of metagenomic DNA and comparison to standards from single cultures. The monitoring indicated consistent growth of these clostridia in the novel cultivation approach.

Downregulation of the Tumor Suppressor SAMHD1 in Classical Hodgkin Lymphoma

Introduction: The SAM domain and HD domain 1 (SAMHD1) protein is a deoxynucleoside triphosphate (dNTP) triphosphohydrolase, which has been initially described to restrict human immunodeficiency virus type 1 (HIV-1) in certain cell types through depletion of intracellular dNTP substrates for HIV-1 reverse transcription. Mutations of SAMHD1 gene have been linked to Aicardi-Goutières syndrome (AGS) and have been identified as putative drivers of chronic lymphocytic leukemia resulting in decreased SAMHD1 mRNA and protein levels. Therefore, a line of evidence suggests that SAMHD1 may play a role in oncogenesis as a tumour suppressor. In addition, SAMHD1 may confer resistance to nucleoside-based chemotherapies by hydrolysing their active triphosphate metabolites, and thus, it may lead to resistance to certain chemotherapeutic agents with cytarabine in acute myeloid leukemia being a recent example (Herold et al, Nat Med 2017; 23(2):256-263). The expression patterns and the potential role of SAMHD1 in the pathogenesis of classical Hodgkin lymphoma (HL) are not yet known.Methods: SAMHD1 protein levels were assessed by Western blot analysis in 20 human lymphoma and leukemia cell lines including 5 classical HL (L1236, L428, HDML2, HDMyZ, MDA-V) and 3 diffuse large B-cell lymphoma (DLBCL) (RC-K8, OCI-Ly3, U2932) cell lines. As our findings from in silico analysis revealed potential binding sites for MYC on the SAMHD1 gene promoter, HL cell lines were treated with selective MYC inhibitors to assess possible MYC-associated regulation of SAMHD1 expression. The patient cohort included 212 cases of classical HL diagnosed and treated at the University of Texas MD Anderson Cancer Center (USA), University of Athens (Greece) and University of Crete (Greece). A control group of 4 reactive lymph nodes and 76 B-cell non-Hodgkin lymphomas (58 DLBCLs) was included in the study for comparison. All tissue samples were obtained prior to therapy. SAMHD1 expression was assessed by immunohistochemistry performed on TMAs with duplicate tumor cores from each case or full tissue sections using a monoclonal antibody (Bethyl Laboratories, San Antonio, TX). An arbitrary 10% cutoff was used to define SAMHD1 positivity in the neoplastic cells. Overall survival (OS) was defined as time from diagnosis to death or last follow-up. Event-free survival (EFS) was defined as time from diagnosis to relapse, death, or last follow-up. Survival analyses were performed using the Kaplan-Meier method (log-rank test) and Cox regression models.Results: In 4 out of 5 HL cell lines, SAMHD1 protein levels were dramatically reduced as compared to all 3 DLBCL and other lymphoma and leukemia cell lines tested. Inhibition of MYC activity resulted in a substantial increase in the SAMHD1 protein level suggesting a possible MYC-associated gene regulation. Similarly, the neoplastic Hodgkin-Reed Sternberg (HRS) cells of classical HL were SAMHD1-negative in 132 of 212 (62.3%) patients. Among the SAMHD1-positive cases, the percentage of positive HRS cells ranged from 10 to 95% with a median 40%. By contrast, SAMHD1 was negative in only 15% of the control group of DLBCLs. In addition, most of the germinal center (GC) cells of the reactive lymph nodes were SAMHD1-positive with consistently higher intensity of immunostaining as compared to HRS cells of classical HL. No significant associations between SAMHD1 levels and clinicopathologic parameters were observed in the HL cohort. In a subset of 56 HL patients with long follow up period (median 195 months), FFS at 10 years was 79% vs. 71% for patients with SAMHD1-negative vs. SAMHD1-positive HL, respectively. Similarly, OS at 15 years was 71% vs. 63% for SAMHD1-negative vs. SAMHD1-positive HL, respectively. These differences did not reach statistical significance (p>0.05, log-rank) likely because of the relatively small number of patients included in this preliminary survival analysis.Conclusions: SAMHD1 is shown for the first time to be downregulated in HRS cells of classical HL further supporting its role as a tumor suppressor and its regulation may involve MYC. Preliminary survival analysis shows a statistical trend towards inferior FFS and OS for patients with SAMHD1-positive HRS cells, however, analysis of the entire cohort of HL patients is underway to draw definite conclusions. DisclosuresKhoury:Pfizer: Research Funding; Angle: Research Funding; Kiromics: Research Funding; Stemline Therapeutics: Research Funding.

Simultaneous ammonium and sulfate biotransformation driven by aeration: Nitrogen/sulfur metabolism and metagenome-based microbial ecology

The present study aimed to clarify the effect of oxygen respiration on biotransformation of alternative electron acceptors (e.g., nitrate and sulfate) underlying the simultaneous removal of ammonium and sulfate in a single aerated sequencing batch reactor. Complete nitrification was achieved in feast condition, while denitrification was carried out in both feast and famine conditions when aeration intensity (AI) was higher than 0.22 L/(L·min). Reactors R1 [0.56 L/(L·min)], R2 [0.22 L/(L·min)], and R3 [0.08 L/(L·min)] achieved 72.39% sulfate removal efficiency in feast condition, but H2S release occurred in R3. Following exogenous substrate depletion, sulfate concentration increased again and exceeded the influent value in R1, indicating that sulfate transformation was affected by oxygen intrusion. Metagenomic analysis showed that a higher AI promoted sulfate reduction by switching from dissimilatory to assimilatory pathway. Lower AI-acclimated microorganisms (R3) produced H2S and ammonium, while higher AI-acclimated microorganisms (R1) accumulated nitrite, which confirmed that biotransformation of N and S was strongly regulated by redox imbalance driven by aeration. This implied that respiration control, a microbial self-regulation mechanism, was linked to the dynamic imbalance between electron donors and electron acceptors. Aerobic nitrate (sulfate) reduction, as one of the effects of respiration control, could be used as an alternative strategy to compensate for dynamic imbalance, when supported by efficient endogenous metabolism. Moderate aeration induced microorganisms to change their energy conservation and survival strategy through respiration control and inter-genus protection of respiratory activity among keystone taxa (including Azoarcus in R1, Thauera in R2, and Thiobacillus, Ottowia, and Geoalkalibacter in R3) to form an optimal niche in response to oxygen intrusion and achieve benign biotransformation of C, N, and S without toxic intermediate accumulation. This study clarified the biotransformation mechanism of ammonium and sulfate driven by aeration and provided theoretical guidance for optimizing existing aeration-based techniques.

Ruthenium Complexes in the Fight against Pathogenic Microorganisms. An Extensive Review.

The widespread use of antibiotics has resulted in the emergence of drug-resistant populations of microorganisms. Clearly, one can see the need to develop new, more effective, antimicrobial agents that go beyond the explored ‘chemical space’. In this regard, their unique modes of action (e.g., reactive oxygen species (ROS) generation, redox activation, ligand exchange, depletion of substrates involved in vital cellular processes) render metal complexes as promising drug candidates. Several Ru (II/III) complexes have been included in, or are currently undergoing, clinical trials as anticancer agents. Based on the in-depth knowledge of their chemical properties and biological behavior, the interest in developing new ruthenium compounds as antibiotic, antifungal, antiparasitic, or antiviral drugs has risen. This review will discuss the advantages and disadvantages of Ru (II/III) frameworks as antimicrobial agents. Some aspects regarding the relationship between their chemical structure and mechanism of action, cellular localization, and/or metabolism of the ruthenium complexes in bacterial and eukaryotic cells are discussed as well. Regarding the antiviral activity, in light of current events related to the Covid-19 pandemic, the Ru (II/III) compounds used against SARS-CoV-2 (e.g., BOLD-100) are also reviewed herein.

Design and Characterization of Backside Termination Structures for Thick Fully-Depleted MAPS.

Fully Depleted Monolithic Active Pixel Sensors (FD-MAPS) represent an appealing alternative to hybrid detectors for radiation imaging applications. We have recently demonstrated the feasibility of FD-MAPS based on a commercial 110 nm CMOS technology, adapted using high-resistivity substrates and backside post-processing. A p/n junction diode, fabricated on the detector backside using low-temperature processing steps after the completion of the front-side Back End of Line (BEOL), is reverse-biased to achieve the full depletion of the substrate and thus fast charge collection by drift. Test diodes including termination structures with different numbers of floating guard rings and different pitches were fabricated together with other Process Control Monitor structures. In this paper, we present the design of the backside diodes, together with results from the electrical characterization of the test devices, aiming to improve understanding of the strengths and limitations of the proposed approach. Characterization results obtained on several wafers demonstrate the effectiveness of the termination rings in increasing the breakdown voltage of the backside diodes and in coping with the variability of the passivation layer characteristics. A breakdown voltage exceeding 400 V in the worst case was demonstrated in devices with 30 guard rings with 6 μm pitch, thus enabling the full depletion of high-resistivity substrates with a thickness larger than or equal to 300 μm. Additionally, we show the first direct comparison for this technology of measured pixel characteristics with 3D TCAD simulations, proving a good agreement in the extracted operating voltages.