Role of Electrolyte pH on Water Oxidation for Iridium Oxides

Understanding the effect of noncovalent interactions of intermediates at the polarized catalyst-electrolyte interface on water oxidation kinetics is key for designing more active and stable electrocatalysts. Here, we combine operando optical spectroscopy, X-ray absorption spectroscopy (XAS), and surface-enhanced infrared absorption spectroscopy (SEIRAS) to probe the effect of noncovalent interactions on the oxygen evolution reaction (OER) activity of IrOx in acidic and alkaline electrolytes. Our results suggest that the active species for the OER (Ir4.x+-*O) binds much stronger in alkaline compared with acid at low coverage, while the repulsive interactions between these species are higher in alkaline electrolytes. These differences are attributed to the larger fraction of water within the cation hydration shell at the interface in alkaline electrolytes compared to acidic electrolytes, which can stabilize oxygenated intermediates and facilitate long-range interactions between them. Quantitative analysis of the state energetics shows that although the *O intermediates bind more strongly than optimal in alkaline electrolytes, the larger repulsive interaction between them results in a significant weakening of *O binding with increasing coverage, leading to similar energetics of active states in acid and alkaline at OER-relevant potentials. By directly probing the electrochemical interface with complementary spectroscopic techniques, our work goes beyond conventional computational descriptors of the OER activity to explain the experimentally observed OER kinetics of IrOx in acidic and alkaline electrolytes.

Cooperative Effects Drive Water Oxidation Catalysis in Cobalt Electrocatalysts through the Destabilization of Intermediates

A barrier to understanding the factors driving catalysis in the oxygen evolution reaction (OER) is understanding multiple overlapping redox transitions in the OER catalysts. The complexity of these transitions obscure the relationship between the coverage of adsorbates and OER kinetics, leading to an experimental challenge in measuring activity descriptors, such as binding energies, as well as adsorbate interactions, which may destabilize intermediates and modulate their binding energies. Herein, we utilize a newly designed optical spectroelectrochemistry system to measure these phenomena in order to contrast the behavior of two electrocatalysts, cobalt oxyhydroxide (CoOOH) and cobalt-iron hexacyanoferrate (cobalt-iron Prussian blue, CoFe-PB). Three distinct optical spectra are observed in each catalyst, corresponding to three separate redox transitions, the last of which we show to be active for the OER using time-resolved spectroscopy and electrochemical mass spectroscopy. By combining predictions from density functional theory with parameters obtained from electroadsorption isotherms, we demonstrate that a destabilization of catalytic intermediates occurs with increasing coverage. In CoOOH, a strong (∼0.34 eV/monolayer) destabilization of a strongly bound catalytic intermediate is observed, leading to a potential offset between the accumulation of the intermediate and measurable O2 evolution. We contrast these data to CoFe-PB, where catalytic intermediate generation and O2 evolution onset coincide due to weaker binding and destabilization (∼0.19 eV/monolayer). By considering a correlation between activation energy and binding strength, we suggest that such adsorbate driven destabilization may account for a significant fraction of the observed OER catalytic activity in both materials. Finally, we disentangle the effects of adsorbate interactions on state coverages and kinetics to show how adsorbate interactions determine the observed Tafel slopes. Crucially, the case of CoFe-PB shows that, even where interactions are weaker, adsorption remains non-Nernstian, which strongly influences the observed Tafel slope.

Transient absorption spectroscopy reveals that slow bimolecular recombination in SrTiO3 underpins its efficient photocatalytic performance

The charge carrier dynamics of SrTiO3 are measured by ultrafast transient absorption spectroscopy, revealing bimolecular recombination kinetics that are at least two magnitudes slower than alternative metal oxides. This slow recombination is associated with its high dielectric constant, and suggested to be central to SrTiO3's high performance in photocatalytic systems.

Detailed Analysis of the Synthesis and Structure of MAX Phase (Mo0.75V0.25)5AlC4 and Its MXene Sibling (Mo0.75V0.25)5C4

MAX phases with the general formula M_n+1AX_n are layered carbides, nitrides, and carbonitrides with varying stacking sequence of layers of M₆X octahedra and the A element depending on n. While "211" MAXphases (n = 1) are very common, MAX phases with higher n, especially n ≥ 3, have hardly been prepared. This work addresses open questions regarding the synthesis conditions, structure, and chemical composition of the "514" MAX phase. In contrast to literature reports, no oxide is needed to form the MAX phase, yet multiple heating steps at 1,600 °C are required. Using high-resolution X-ray diffraction, the structure of (Mo_1-xV_x)₅AlC₄ is thoroughly investigated, and Rietveld refinement suggests P-6c2 as the most fitting space group. SEM/EDS and XPS show that the chemical composition of the MAX phase is (Mo_0.75V_0.25)₅AlC₄. It was also exfoliated into its MXene sibling (Mo_0.75V_0.25)₅C₄ using two different techniques (using HF and an HF/HCl mixture) that lead to different surface terminations as shown by XPS/HAXPES measurements. Initial investigations of the electrocatalytic properties of both MXene versions show that, depending on the etchant, (Mo_0.75V_0.25)₅C₄ can reduce hydrogen at 10 mA cm^-2 with an overpotential of 166 mV (HF only) or 425 mV (HF/HCl) after cycling the samples, which makes them a potential candidate as an HER catalyst.

Water Increases the Faradaic Selectivity of Li-Mediated Nitrogen Reduction

The lithium-mediated system catalyzes nitrogen to ammonia under ambient conditions. Herein we discover that trace amount of water as an electrolyte additive-in contrast to prior reports from the literature-can effect a dramatic improvement in the Faradaic selectivity of N₂ reduction to NH₃. We report that an optimal water concentration of 35.9 mM and LiClO₄ salt concentration of 0.8 M allows a Faradaic efficiency up to 27.9 ± 2.5% at ambient pressure. We attribute the increase in Faradaic efficiency to the incorporation of Li₂O in the solid electrolyte interphase, as suggested by our X-ray photoelectron spectroscopy measurements. Our results highlight the extreme sensitivity of lithium-mediated N₂ reduction to small changes in the experimental conditions.

POS0194 MORBIDITY AND MORTALITY OF BREAKTHROUGH COVID-19 IN PATIENTS WITH IMMUNE MEDIATED CONDITIONS ON B CELL DEPLETING THERAPIES AND THE EFFECTS OF MONOCLONAL ANTIBODY TREATMENT

Background

Among immunocompromised patients with immune mediated inflammatory diseases (IMIDs), those undergoing therapy with B cell depleting agents are among the most vulnerable to both severe COVID-19 disease and sub-optimal response to COVID-19 vaccines(1). Numerous studies have documented suppressed humoral, but relatively maintained cell mediated, responses to COVID-19 vaccines in these patients. However, the clinical significance of such immunity in terms of protection from infection and its sequelae are poorly understood. We have analyzed a large cohort of vaccinated IMIDs patients undergoing B cell depleting therapy for the presence of breakthrough infection and assessed their outcomes.

Objectives:

To define the frequency and outcomes of COVID-19 breakthrough infection in fully or partially vaccinated IMIDs patients receiving B cell depleting therapies.

To assess the characteristics and risk factors for severe outcomes and death.

Methods

All pharmacy records from within a large health care system were electronically searched for patients undergoing B cell depleting therapies with approved monoclonal antibodies in 2020. Records with ICD codes for IMIDs but not malignancies were included; patients must also have had at least one documented COVID-19 vaccine. From this cohort all patients with breakthrough COVID-19 disease from time of 1st vaccination through December 15, 2021 were identified; each record was hand-reviewed to extract clinical data including vaccine history, demographics, comorbidities, use of monoclonal antibodies, dose and timing of B cell depleting therapy, and outcomes as assessed by an 8 point NIH ordinal scale. Univariate and multivariable logistic/proportional-odds regression models were used to examine the risk factors for severe outcomes.

Results

A total of 1677 IMIDs patients were identified who received any B cell depleting monoclonal antibody and at least one COVID-19 vaccine in 2021. From this cohort 74 patients (4.4%) experienced a breakthrough COVID-19 infection. Among the breakthrough patients 34 (46%) had a rheumatic disease (RA 11, AAV 15, SLE 2), 34 (46%) had CNS inflammatory disease (MS 32, 2 other), and 6 (8%) had immune hematologic/miscellaneous diseases. Four patients had a previous history of COVID-19 infection. Overall 24 (35%) were hospitalized with 11 patients requiring critical level care (15%) and 6 deaths (8 %). All fatal cases had rheumatic diseases. Monoclonal antibodies were given as outpatient therapy to 21 patients and among these only 1 patient was hospitalized without requiring O2 and none died. In univariate analysis only number of comorbidities had a significant positive effect (p=.001) on severe outcomes (i.e. groups 1-4 vs. groups 5-8: Table 1) while monoclonal antibody therapy was associated with more favorable outcomes (p=.005 group 1-2 vs.3-8, Table 1). There were no associations between the dose, duration or timing of the B cell therapy, concomitant therapies including glucocorticoids, vaccine status (incomplete, complete, boosted) or date of vaccination with severe outcomes.

Conclusion

In IMIDs patients treated with B cell depleting therapies breakthrough infections are common with many experiencing severe outcomes. Concomitant comorbidities were associated with risk of severe disease. Monoclonal antibody therapy was used in only 28% but was associated with enhanced clinical outcomes with only 1 in 21 requiring hospitalization and zero mortality. This population of immunocompromised patients remains vulnerable to COVID-19 disease despite vaccination. More aggressive use of outpatient management with monoclonal antibody therapy and other preventive and therapeutic measures are urgently needed.

Reference

[1]Samuel Bitoun et al Rituximab impairs B-cell response but not T-cell response to COVID-19 vaccine in auto-immune diseases First published: 28 December 2021 Arthritis and Rheumatology https://doi.org/10.1002/art.42058

Disclosure of Interests

cassandra calabrese Speakers bureau: Sanofi-regeneron, Consultant of: Sanofi-regeneron, Elizabeth Kirchner Consultant of: Janssen, M Elaine Husni Consultant of: Abbvie, BMS, Novartis, Lilly, Pfizer, UCB, Regeneron, Janssen, Brandon Moss Consultant of: Biogen advisory board, Grant/research support from: Genentech/Roche and Novartis as part of investigator-initiated studies, Anthony Fernandez Consultant of: Consulting: AbbVie, Novartis, Mallinckrodt, UCB, BMS, Boehringer Ingelheim, Alexion, Grant/research support from: Research: AbbVie, Novartis, Pfizer, Corbus, Mallinckrodt, Yuxuan Jin: None declared, Leonard Calabrese Speakers bureau: Sanofi, Janssen, AbbVie, ChemoCentryx, GSK, AstraZeneca, Consultant of: Sanofi, Jansen, AbbVie, ChemoCentryx, GSK, AstraZeneca, BMS, Genentech

Effect of Band Bending in Photoactive MOF-Based Heterojunctions

Semiconductor/metal-organic framework (MOF) heterojunctions have demonstrated promising performance for the photoconversion of CO₂ into value-added chemicals. To further improve performance, we must understand better the factors which govern charge transfer across the heterojunction interface. However, the effects of interfacial electric fields, which can drive or hinder electron flow, are not commonly investigated in MOF-based heterojunctions. In this study, we highlight the importance of interfacial band bending using two carbon nitride/MOF heterojunctions with either Co-ZIF-L or Ti-MIL-125-NH₂. Direct measurement of the electronic structures using X-ray photoelectron spectroscopy (XPS), work function, valence band, and band gap measurements led to the construction of a simple band model at the heterojunction interface. This model, based on the heterojunction components and band bending, enabled us to rationalize the photocatalytic enhancements and losses observed in MOF-based heterojunctions. Using the insight gained from a promising band bending diagram, we developed a Type II carbon nitride/MOF heterojunction with a 2-fold enhanced CO₂ photoreduction activity compared to the physical mixture.

"Loneliness can also kill:" a qualitative exploration of outcomes and experiences of the SUPERB peer-befriending scheme for people with aphasia and their significant others

PURPOSE

People with aphasia post-stroke are at risk for depression and social isolation. Peer-befriending from someone with similar experiences may promote wellbeing and provide support. This paper explored the views of people with aphasia and their significant others about peer-befriending.

MATERIALS AND METHODS

We conducted a qualitative study within a feasibility trial (SUPERB) on peer-befriending for people with post-stroke aphasia and low levels of distress. Of the 28 participants randomised to the intervention, semi-structured in-depth interviews were conducted with 10 purposively selected people with aphasia (at both 4- and 10-months post-randomisation) and five of their significant others (at 4-months). Interviews were analysed using Framework Analysis.

RESULTS

Participants and their significant others were positive about peer-befriending and identified factors which influenced their experience: the befrienders' personal experience of stroke and aphasia, their character traits and the resulting rapport these created, the conversation topics they discussed and settings they met in, and the logistics of befriending, including planning visits and negotiating their end. Interviewees also made evaluative comments about the befriending scheme.

CONCLUSION

Peer-befriending was an acceptable intervention. Benefits for emotional wellbeing and companionship were reported. The shared experience in the befriending relationship was highly valued.Implications for RehabilitationThe lived experience of stroke and aphasia of befrienders was highly valued by people with aphasia receiving peer-befriending.Training, regular supervision, and support for befrienders with practicalities such as organising visits ensured the befriending scheme was perceived as straightforward and acceptable by befriendees.Those receiving peer-befriending would recommend it to others; they found it beneficial, especially in terms of emotional wellbeing and companionship.

"For them and for me": a qualitative exploration of peer befrienders' experiences supporting people with aphasia in the SUPERB feasibility trial

PURPOSE

Peer-befriending, where support is offered by someone with shared lived experience, is an intervention that may facilitate successful adjustment in people experiencing post-stroke aphasia. This paper explores the experiences of the peer-befrienders.

MATERIALS AND METHODS

People with aphasia were recruited as peer-befrienders within the SUPERB trial investigating befriending for people with post-stroke aphasia. The intervention comprised six visits over three months. Peer-befrienders were matched with at least one befriendee and received training and ongoing supervision. They were invited to participate in in-depth interviews which were analysed using framework analysis.

RESULTS

All 10 befrienders participated in interviews, reporting on 19 matches. Seven main themes emerged: content of the sessions; befriender-befriendee relationship; negotiating the visits; handling boundaries and endings; positive impact of the befriending for befrienders and befriendees; and beliefs about the nature and value of peer support. While befrienders described challenges, such as negotiating journeys and witnessing distress, the role was perceived as a "secure challenge" due to the support and training received.

CONCLUSIONS

Befrienders perceived the role as enjoyable and rewarding, and felt they were making a positive difference. They were unanimous in believing that people with aphasia can offer unique and valuable support to others with aphasia.

TRIAL REGISTRATION

ClinicalTrials.gov identifier NCT02947776, registered 28th October 2016.Implications for rehabilitationPeople with lived experience of stroke and aphasia were able to offer emotional and social peer support to others with aphasia within the SUPERB trial.Although there were challenges, peer befrienders perceived the role as rewarding and satisfying.Peer befrienders valued the training and ongoing supervision and support they received to deliver the intervention.It is recommended that rehabilitation professionals considering offering peer-befriending schemes provide training and ongoing supervision to support peer-befrienders fulfil their role, as well as practical support with, e.g., arranging visits.

Linking in situ charge accumulation to electronic structure in doped SrTiO3 reveals design principles for hydrogen-evolving photocatalysts

Recently, high solar-to-hydrogen efficiencies were demonstrated using La and Rh co-doped SrTiO₃ (La,Rh:SrTiO₃) incorporated into a low-cost and scalable Z-scheme device, known as a photocatalyst sheet. However, the unique properties that enable La,Rh:SrTiO₃ to support this impressive performance are not fully understood. Combining in situ spectroelectrochemical measurements with density functional theory and photoelectron spectroscopy produces a depletion model of Rh:SrTiO₃ and La,Rh:SrTiO₃ photocatalyst sheets. This reveals remarkable properties, such as deep flatband potentials (+2 V versus the reversible hydrogen electrode) and a Rh oxidation state dependent reorganization of the electronic structure, involving the loss of a vacant Rh 4d mid-gap state. This reorganization enables Rh:SrTiO₃ to be reduced by co-doping without compromising the p-type character. In situ time-resolved spectroscopies show that the electronic structure reorganization induced by Rh reduction controls the electron lifetime in photocatalyst sheets. In Rh:SrTiO₃, enhanced lifetimes can only be obtained at negative applied potentials, where the complete Z-scheme operates inefficiently. La co-doping fixes Rh in the 3+ state, which results in long-lived photogenerated electrons even at very positive potentials (+1 V versus the reversible hydrogen electrode), in which both components of the complete device operate effectively. This understanding of the role of co-dopants provides a new insight into the design principles for water-splitting devices based on bandgap-engineered metal oxides.

Impact of the Synthesis Route on the Water Oxidation Kinetics of Hematite Photoanodes

Operando spectroelectrochemical analysis is used to determine the water oxidation reaction kinetics for hematite photoanodes prepared using four different synthetic procedures. While these photoanodes exhibit very different current/voltage performance, their underlying water oxidation kinetics are found to be almost invariant. Higher temperature thermal annealing was found to correlate with a shift in the photocurrent onset potential toward less positive potentials, assigned to a suppression of both back electron-hole recombination and of charge accumulation in intra-bandgap states, indicating these intra-bandgap states do not contribute directly to water oxidation.

V2O5 as magnesium cathode material with extended cyclic stability

In this work, the electrochemical performance of aerosol-assisted chemical vapour deposited vanadium pentoxide cathodes at 600 °C, is presented. The as-grown oxides indicate specific discharge capacity of 300 mA h g-1 with capacity retention of 92 % after 10000 scans, coulombic efficiency of 100 %, noble structural stability and high reversibility. The present study shows the possibility to grow large-area magnesium cathode material with extended cycle stability via utilization of an aqueous electrolyte under a corrosive environment. This enhanced performance may be a combination of electrode morphology and adherence, when compared to previous work employing electrode growth temperature at 500 °C.

Abstract 265: Improving Compliance with Get with the Guidelines-Resuscitation Metrics by Standardizing Code Note Documentation

Background: Accurate documentation of in-hospital cardiac arrest is essential to patient care. Recently, the American Heart Association created Get with the Guidelines-Resuscitation (GWTG-R) to facilitate the capture, analysis, and reporting of cardiac arrest data. GWTG-R criteria include witnessed events, confirmation of airway, two minute time-to-shock for ventricular tachycardia or fibrillation, and five minute time-to-first dose of epinephrine for pulseless electrical activity. The goal of our study was to increase adherence to GWTG-R measures by improving the quality of documentation of cardiac arrests by resident code leaders through the development and implementation of a standardized code note template.

Methods: A retrospective chart review was performed on resident-authored code notes before and after implementation of a standardized code note. An electronic medical record template was developed which highlighted GWTG-R metrics. This note was made available to all resident physician code leaders. Reviewed notes were assessed for documentation of GWTG-R metrics and clinical reasoning.

Results: Twenty-two notes were reviewed prior to and seventeen notes after implementation of a standardized code note template. 14/17 (82%) of post-implementation notes used the standardized template. All GWTG-R categories and clinical reasoning documentation trended toward improvement. Documentation of time-to-epinephrine significantly increased from 5.9% to 91.7% (Figure 1).

Conclusions: Development of a standardized code note template improved documentation of GWTG-R quality measures for in-hospital cardiac arrest. Hospital compliance with guidelines improved following this intervention, qualifying for GWTG-R Bronze for three consecutive months of compliance. Expansion of the standardized code note for widespread use by providers throughout the hospital is expected to continue to improve code documentation and hospital compliance with GWTG-R.

The Effect of Materials Architecture in TiO2 /MOF Composites on CO2 Photoreduction and Charge Transfer

CO₂ photoreduction to C₁ /C₁₊ energized molecules is a key reaction of solar fuel technologies. Building heterojunctions can enhance photocatalysts performance, by facilitating charge transfer between two heterojunction phases. The material parameters that control this charge transfer remain unclear. Here, it is hypothesized that governing factors for CO₂ photoreduction in gas phase are: i) a large porosity to accumulate CO₂ molecules close to catalytic sites and ii) a high number of "points of contact" between the heterojunction components to enhance charge transfer. The former requirement can be met by using porous materials; the latter requirement by controlling the morphology of the heterojunction components. Hence, composites of titanium oxide or titanate and metal-organic framework (MOF), a highly porous material, are built. TiO₂ or titanate nanofibers are synthesized and MOF particles are grown on the fibers. All composites produce CO under UV-vis light, using H₂ as reducing agent. They are more active than their component materials, e.g., ≈9 times more active than titanate. The controlled composites morphology is confirmed and transient absorption spectroscopy highlights charge transfer between the composite components. It is demonstrated that electrons transfer from TiO₂ into the MOF, and holes from the MOF into TiO₂ , as the MOF induces band bending in TiO₂ .

The Predictive Ability of Pre-Operative Magnetic Resonance Imaging to Detect Pathological Outcomes in Prostate Cancer

Aims Accurate preoperative knowledge of tumour stage is important in preoperative planning at radical prostatectomy (RP). The aim of this study was to assess the predictive ability of multiparametric MRI for detecting pathological outcomes. Methods A retrospective review was performed of all patients who underwent RP over a 4 year period. Results Preoperative MRI was reported as showing T3 or T4 disease in 26(17.9%) out of 145 patients undergoing RP. Of these, 10(6.9%) had ECE (extra-capsular extension) and 1(0.7%) had SVI (seminal vesicle invasion) on final histology. The sensitivity and specificity of MRI for detecting ECE were 27.3% and 87.6%, respectively. The sensitivity and specificity of MRI for detecting SVI were 11.1% and 97.8%, respectively. The positive predictive values for determining ECE and SVI were 45.5% and 25%, respectively and negative predictive values were 75.9% and 94.4%. Conclusion MRI has good specificity but poor and heterogeneous sensitivity for predicting T3 disease in RP specimen.

HIVIS-DNA or HIVISopt-DNA priming followed by CMDR vaccinia-based boosts induce both humoral and cellular murine immune responses to HIV

Background

In order to develop a more effective prophylactic HIV-1 vaccine it is important optimize the components, improve Envelope glycoprotein immunogenicity as well as to explore prime-boost immunization schedules. It is also valuable to include several HIV-1 subtype antigens representing the world-wide epidemic.

Methods

HIVIS-DNA plasmids which include Env genes of subtypes A, B and C together with Gag subtypes A and B and RTmut/Rev of subtype B were modified as follows: the Envelope sequences were shortened, codon optimized, provided with an FT4 sequence and an immunodominant region mutated. The reverse transcriptase (RT) gene was shortened to contain the most immunogenic N-terminal fragment and fused with an inactivated viral protease vPR gene. HIVISopt-DNA thus contains fewer plasmids but additional PR epitopes compared to the native HIVIS-DNA. DNA components were delivered intradermally to young Balb/c mice once, using a needle-free Biojector® immediately followed by dermal electroporation. Vaccinia-based MVA-CMDR boosts including Env gene E and Gag-RT genes A were delivered intramuscularly by needle, once or twice.

Results

Both HIVIS-DNA and HIVISopt-DNA primed humoral and cell mediated responses well. When boosted with heterologous MVA-CMDR (subtypes A and E) virus inhibitory neutralizing antibodies were obtained to HIV-1 subtypes A, B, C and AE. Both plasmid compositions boosted with MVA-CMDR generated HIV-1 specific cellular responses directed against HIV-1 Env, Gag and Pol, as measured by IFNγ ELISpot. It was shown that DNA priming augmented the vector MVA immunological boosting effects, the HIVISopt-DNA with a trend to improved (Env) neutralization, the HIVIS-DNA with a trend to better (Gag) cell mediated immune reponses.

Conclusions

HIVIS-DNA was modified to obtain HIVISopt-DNA that had fewer plasmids, and additional epitopes. Even with one DNA prime followed by two MVA-CMDR boosts, humoral and cell-mediated immune responses were readily induced by priming with either DNA construct composition. Priming by HIV-DNA augmented neutralizing antibody responses revealed by boosting with the vaccinia-based heterologous sequences. Cellular and antibody responses covered selected strains representing HIV-1 subtypes A, B, C and CRF01_AE. We assume this is related to the inclusion of heterologous full genes in the vaccine schedule.

Comparing photoelectrochemical water oxidation, recombination kinetics and charge trapping in the three polymorphs of TiO2

In this article we present the first comparative study of the transient decay dynamics of photo-generated charges for the three polymorphs of TiO₂. To our knowledge, this is the first such study of the brookite phase of TiO₂ over timescales relevant to the kinetics of water splitting. We find that the behavior of brookite, both in the dynamics of relaxation of photo-generated charges and in energetic distribution, is similar to the anatase phase of TiO₂. Moreover, links between the rate of recombination of charge carriers, their energetic distribution and the mode of transport are made in light of our findings and used to account for the differences in water splitting efficiency observed across the three polymorphs.

Prison prescribing practice: practitioners' perspectives on why prison is different

The current prison population in England and Wales has multiple, complex healthcare needs, presenting unique challenges to those caring for prisoners. Prison numbers have increased dramatically in the last 10 years. There are now approximately 84,000 prisoners in England and Wales and 120,000 new episodes of imprisonment each year . The authors all contribute to prison healthcare. Below, we discuss a key issue arising from first-hand experience of prisoners' health and social care needs, the prescription of psycho-active drugs by primary and secondary care practitioners. This is a core medical task, but beset with difficulties. These difficulties are not necessarily encountered in other areas of prison healthcare. However, they do illustrate how providing healthcare to prisoners is complex, often lacking a research base and can have pitfalls that are not obvious to the outsider.

Depletion-mode carrier-plasma optical modulator in zero-change advanced CMOS

We demonstrate the first (to the best of our knowledge) depletion-mode carrier-plasma optical modulator fabricated in a standard advanced complementary metal-oxide-semiconductor (CMOS) logic process (45 nm node SOI CMOS) with no process modifications. The zero-change CMOS photonics approach enables this device to be monolithically integrated into state-of-the-art microprocessors and advanced electronics. Because these processes support lateral p-n junctions but not efficient ridge waveguides, we accommodate these constraints with a new type of resonant modulator. It is based on a hybrid microring/disk cavity formed entirely in the sub-90 nm thick monocrystalline silicon transistor body layer. Electrical contact of both polarities is made along the inner radius of the multimode ring cavity via an array of silicon spokes. The spokes connect to p and n regions formed using transistor well implants, which form radially extending lateral junctions that provide index modulation. We show 5 Gbps data modulation at 1265 nm wavelength with 5.2 dB extinction ratio and an estimated 40 fJ/bit energy consumption. Broad thermal tuning is demonstrated across 3.2 THz (18 nm) with an efficiency of 291 GHz/mW. A single postprocessing step to remove the silicon handle wafer was necessary to support low-loss optical confinement in the device layer. This modulator is an important step toward monolithically integrated CMOS photonic interconnects.

Open foundry platform for high-performance electronic-photonic integration

This paper presents photonic devices with 3 dB/cm waveguide loss fabricated in an existing commercial electronic 45 nm SOI-CMOS foundry process. By utilizing existing front-end fabrication processes the photonic devices are monolithically integrated with electronics in the same physical device layer as transistors achieving 4 ps logic stage delay, without degradation in transistor performance. We demonstrate an 8-channel optical microring-resonator filter bank and optical modulators, both controlled by integrated digital circuits. By developing a device design methodology that requires zero process infrastructure changes, a widely available platform for high-performance photonic-electronic integrated circuits is enabled.

Abstract 2222: Oncogene-mediated alterations in chromatin conformation

Emerging evidence suggests that chromatin adopts a non-random three dimensional (3D) topology and that the organization of genes into structural hubs and domains affects their transcriptional status. How chromatin conformation changes in diseases such as cancer is poorly understood. Moreover, how oncogenic transcription factors, which bind to thousands of sites across the genome, influence gene regulation by globally altering the topology of chromatin requires further elucidation. To address these questions, we performed unbiased high-resolution mapping of intra- and inter-chromosome interactions upon over-expression of ERG, an oncogenic transcription factor frequently over-expressed in prostate cancer as a result of a gene fusion. By integrating data from genome-wide chromosome conformation capture (Hi-C), ERG binding and gene expression, we demonstrate for the first time that an oncogenic transcription factor can induce global, reproducible and functionally coherent changes in chromatin organization. We also show using spectral karyotyping that ERG over-expression is associated with a specific translocation involving chromosomes 13 and 15 at loci that are enriched in ERG binding. The results presented here have broader implications, as many driving genetic lesions in other cancer types involve altered levels of transcription factors due to genomic alterations (e.g. EWS-FLI1, c-Myc, n-Myc, PML-RARα).

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2222. doi:1538-7445.AM2012-2222

Abstract A31: ERG-mediated alterations in chromatin conformation

Emerging evidence suggests that chromatin adopts a non-random three dimensional (3D) topology and that the organization of genes into structural hubs and domains affects their transcriptional status. How chromatin conformation changes in diseases such as cancer is poorly understood. Moreover, how oncogenic transcription factors, which bind to thousands of sites across the genome, influence gene regulation by globally altering the topology of chromatin requires further elucidation. To address these questions, we performed unbiased high-resolution mapping of intra- and inter-chromosome interactions upon over-expression of ERG, an oncogenic transcription factor frequently over-expressed in prostate cancer as a result of a gene fusion. By integrating data from genome-wide chromosome conformation capture (Hi-C), ERG binding (ChIP-seq), gene expression (RNA-seq) and spectral karytopying, we demonstrate for the first time that the oncogenic transcription factor ERG can induce global, reproducible and functionally coherent changes in chromatin organization that are associated with gene expression differences and genomic alterations. The results presented here have broader implications, as many driving genetic lesions in other cancer types involve altered levels of transcription factors due to genomic alterations (e.g. EWS-FLI1, c-Myc, n-Myc, PML-RARα).

Citation Format: David S. Rickman, Ari Melnick, Olivier Elemento, Mark Rubin, T. David Soong, Benjamin Moss, Juan Miguel Mosquera, Jan Dlabal, Stephane Terry, Theresa MacDonald, Karen Bunting, Francesca Demichelis. ERG-mediated alterations in chromatin conformation [abstract]. In: Proceedings of the AACR Special Conference on Advances in Prostate Cancer Research; 2012 Feb 6-9; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2012;72(4 Suppl):Abstract nr A31.

Abstract LB-249: Oncogene-mediated alterations in chromatin conformation

Emerging evidence suggests that the three-dimensional structure of chromosomes is not random but rather organized into compartments of open and closed chromatin and that this architectural organization plays a major role in gene regulation and genomic aberrations. There is evidence that transcription factors mediate chromatin topology and have been implicated in DNA breaks leading to genomic rearrangement. However, no study, to date, has described a comprehensive, genome-wide characterization of chromatin topological changes, gene regulation, and genomic alterations that can be attributed to oncogenic transcription factors. ETS rearranged prostate cancers, similar to other translocation tumors, represent a common and distinct molecular subclass of PCa based on studies demonstrating characteristic morphologic features, natural history and specific genomic and expression profiles. We hypothesize that ERG mediates specific alterations in chromatin structure that translates into changes in gene expression and genomic alterations in prostate cancer. We used next-generation DNA sequencing and chromosome conformation capture technology (Hi-C) to systematically map long-range chromatin interactions in the prostate cancer genomes of isogenic cell lines that differ in respect to ERG over-expression. Two biological replicate HiC samples were sequenced using five lanes of an Illumina GAIIx flow cell per cell line. After filtering, we obtained a total of roughly 20 million paired end sequence reads that corresponded to intra- and interchromosome interactions per cell line. We validated specific long-range interactions using targeted PCR from 3C libraries and using fluorescent in situ hybridization (FISH). In addition, we performed chromatin-immunoprecipitation with DNA sequencing (ChIPseq) and next generation RNA sequencing (RNA-seq) on the same cell lines to evaluate areas of ERG binding, determine the landscape of histone marks and quantify differential mRNA expression. We identified chromosomal interactions that appear to be dependent on ERG expression and these interactions are associated with ERG binding and changes in gene expression. Finally, we performed an integrative analysis of available whole genome DNA sequencing data (30 x coverage) from 7 prostate cancer samples (Berger et al., Nature 2011) and found associations between mapped genomic rearrangement, ERG binding and cell line specific long range chromosome interactions. Our study indicates, for the first time, that oncogenic transcription factors exert a broad effect on chromatin topology and associated gene regulation, and suggest that chromatin conformation predisposes the genome for later rearrangement events.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr LB-249. doi:10.1158/1538-7445.AM2011-LB-249

The pre-melt phase of n-alkanes: Crystallographic evidence for a kinked chain structure

Electron diffraction measurements on epitaxially grown crystals of orthorhombic n-hexatriacontane, n-C(36)H(74), give evidence for the chain-defect mechanism for linear chain melting. The derived structural model is also in accord with recent spectroscopic studies of odd-chain n-alkanes, and the diffraction data specifically exclude models based on helices or rigid chain rotors. Stability of a kinked chain structure, moreover, is indicated by an observed hysteresis effect that gives different pretransition temperatures for solution-grown and annealed crystals.

Dinucleotide Sequences at the 5' Ends of Vaccinia Virus mRNA's Synthesized In Vitro

The diversity of dinucleotide sequences at the 5' ends of vaccinia virus mRNA's was determined by a two-dimensional electrophoresis procedure. RNA labeled with S-adenosyl[methyl-(3)H]methionine was synthesized in vitro by enzymes present in vaccinia virus cores. The RNA, ending in m(7)G(5')pppN(m)pN-, was beta-eliminated and treated with alkaline phosphatase. After digestion with RNases T(2), T(1), and A, all eight possible dinucleotides containing G(m) and A(m) were identified. They are, in decreasing order of abundance: G(m)pUp (22%), A(m)pCp (18%), G(m)pAp (16%), G(m)pCp (15%), A(m)pAp (11%), A(m)pUp (10%), A(m)pGp (7%), and G(m)pGp (2%).

Abstract LB-21: Emergence of castration resistant prostate cancer class defined by recurrent ERG fusion

The role of recurrent ETS gene fusions in castration resistant prostate cancer (CRPC) is poorly understood. We characterized the transcriptome of CRPC by interrogating a cohort of 54 men with locally advanced or metastatic CRPC using a gene expression profiling method recently established for formalin-fixed paraffin-embedded tissue. We found increased expression of multiple genes in ERG rearranged tumors which suggests a selective growth advantage under oxygen poor conditions. We discovered that trefoil factor 3 (TFF3) is the top differentially regulated gene by both ERG rearrangement and resistance to therapy. Conventional chromatin immunoprecipitation (ChIP)-PCR and ChIP-seq data revealed direct binding of ERG to ETS binding sites in the TFF3 promoter in ERG rearranged prostate cancer cell lines, which was confirmed in ERG rearranged hormone naïve prostate cancer (HNPC) and CRPC tissue samples. In vitro data suggested that ERG has an inhibitory effect on TFF3 expression in hormone naïve cancer, which was relieved in CRPC depending on the level of AR expression. These findings reveal an interplay between ERG rearrangement and AR signaling in CRPC, and provide perspective towards novel therapeutic targets.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr LB-21.

SLC45A3-ELK4 is a novel and frequent erythroblast transformation-specific fusion transcript in prostate cancer

Chromosomal rearrangements account for all erythroblast transformation-specific (ETS) family member gene fusions that have been reported in prostate cancer and have clinical, diagnostic, and prognostic implications. Androgen-regulated genes account for the majority of the 5' genomic regulatory promoter elements fused with ETS genes. TMPRSS2-ERG, TMPRSS2-ETV1, and SLC45A3-ERG rearrangements account for roughly 90% of ETS fusion prostate cancer. ELK4, another ETS family member, is androgen regulated, involved in promoting cell growth, and highly expressed in a subset of prostate cancer, yet the mechanism of ELK4 overexpression is unknown. In this study, we identified a novel ETS family fusion transcript, SLC45A3-ELK4, and found it to be expressed in both benign prostate tissue and prostate cancer. We found high levels of SLC45A3-ELK4 mRNA restricted to a subset of prostate cancer samples. SLC45A3-ELK4 transcript can be detected at high levels in urine samples from men at risk for prostate cancer. Characterization of the fusion mRNA revealed a major variant in which SLC45A3 exon 1 is fused to ELK4 exon 2. Based on quantitative PCR analyses of DNA, unlike other ETS fusions described in prostate cancer, the expression of SLC45A3-ELK4 mRNA is not exclusive to cases harboring a chromosomal rearrangement. Treatment of LNCaP cancer cells with a synthetic androgen (R1881) revealed that SLC45A3-ELK4, and not endogenous ELK4, mRNA expression is androgen regulated. Altogether, our findings show that SLC45A3-ELK4 mRNA expression is heterogeneous, highly induced in a subset of prostate cancers, androgen regulated, and most commonly occurs through a mechanism other than chromosomal rearrangement (e.g., trans-splicing).

Gene expression using the vaccinia virus/ T7 RNA polymerase hybrid system

This unit describes a transient cytoplasmic expression system that relies on the synthesis of the bacteriophage T7 RNA polymerase in the cytoplasm of mammalian cells. A gene of interest is inserted into a plasmid such that it comes under the control of the T7 RNA polymerase promoter (p(T7)). Using liposome-mediated transfection, this recombinant plasmid is introduced into the cytoplasm of cells infected with vTF7-3, a recombinant vaccinia virus encoding bacteriophage T7 RNA polymerase. During incubation, the gene of interest is transcribed with high efficiency by T7 RNA polymerase. For large-scale work, protocols are provided for insertion of the p(T7)-regulated gene into a second recombinant vaccinia virus by homologous recombination and subsequent coinfection with vTF7-3 into cells grown in suspension or for direct transfection into OST7-1 cells (a stable cell line that constitutively expresses the T7 RNA polymerase). Expressed protein is then analyzed by pulse-labeling and purified. One new development to this vaccinia virus/T7 RNA polymerase hybrid expression system described here is the VOTE inducible expression system, which eliminates the need to use two recombinant viruses or a special cell line.

Overview of the vaccinia virus expression system

The vaccinia virus expression system differs from others in that transcription occurs in the cytoplasm of mammalian cells rather than in the nucleus. As a vector, vaccinia virus has a number of useful characteristics, including a capacity that permits cloning large fragments of foreign DNA (20+ kbp) with retention of infectivity, a wide host range, a relatively high level of protein synthesis, and "appropriate" transport, secretion, processing, and posttranslational modifications as dictated by the primary structure of the expressed protein and the cell type used. This overview discusses the life cycle of the vaccinia virus along with effects of vaccinia infection. The vaccinia vector expression system is described along with specific steps for expressing genes using these vectors. Important safety considerations are also presented.

Generation of recombinant vaccinia viruses

This unit first describes how to infect cells with vaccinia virus and then transfect them with a plasmid-transfer vector to generate a recombinant virus. Methods are also presented for purifying vaccinia virus and for isolating viral DNA, which can be used during transfection. Also presented are selection and screening methods used to isolate recombinant viruses and a method for the amplification of recombinant viruses. Finally, a method for live immunostaining that has been used primarily for detection of recombinant modified vaccinia virus Ankara (MVA) is presented.

Characterization of recombinant vaccinia viruses and their products

After a recombinant vaccinia virus is made, its DNA and protein products can be analyzed in several ways. Protocols are provided in this unit for identification of the recombinant virus by PCR (with verification of correct insertion of the DNA by Southern blotting) and by dot-blot hybridization. Also, when antibodies are available, protein expression can be analyzed by immunological methods detailed here such as dot blotting with an antibody, immunoblotting and/or immunoprecipitation. In addition, immunostaining can be used for identification of recombinant plaques as well as for determination of the purity of a recombinant virus stock. All of the protocols in this unit can be used for characterization of modified vaccinia virus Ankara (MVA) recombinant viruses.

Generation of recombinant vaccinia viruses

This unit first describes how to infect cells with vaccinia virus and then transfect them with a plasmid-transfer vector to generate a recombinant virus. Methods are also presented for purifying vaccinia virus and for isolating viral DNA, which can be used during transfection. Also presented are selection and screening methods used to isolate recombinant viruses and a method for the amplification of recombinant viruses. Finally, a method for live immunostaining that has been used primarily for detection of recombinant modified vaccinia virus Ankara (MVA) is presented.

Preparation of cell cultures and vaccinia virus stocks

This unit describes the maintenance of cell lines used with vaccinia virus, both in monolayer cultures and in suspension. The suspended cell culture is then used in the preparation of vaccinia virus stocks. The preparation of chick embryo fibroblasts (CEF) is also presented for use in the production of the highly attenuated and host range-restricted modified vaccinia virus Ankara (MVA) strain of vaccinia virus. Additionally, support protocols are presented for the titration of standard and MVA vaccinia virus stocks.

Characterization of recombinant vaccinia viruses and their products

After a recombinant vaccinia virus is made, its DNA and protein products can be analyzed in several ways. Protocols are provided in this unit for identification of the recombinant virus by PCR (with verification of correct insertion of the DNA by Southern blotting) and by dot-blot hybridization. Also, when antibodies are available, protein expression can be analyzed by immunological methods detailed here such as dot blotting with an antibody, immunoblotting and/or immunoprecipitation. In addition, immunostaining can be used for identification of recombinant plaques as well as for determination of the purity of a recombinant virus stock. All of the protocols in this unit can be used for characterization of modified vaccinia virus Ankara (MVA) recombinant viruses.

Gene expression using the vaccinia virus/T7 RNA polymerase hybrid system

This unit describes a transient cytoplasmic expression system that relies on the synthesis of the bacteriophage T7 RNA polymerase in the cytoplasm of mammalian cells. A gene of interest is inserted into a plasmid such that it comes under the control of the T7 RNA polymerase promoter (p(T7)). Using liposome-mediated transfection, this recombinant plasmid is introduced into the cytoplasm of cells infected with vTF7-3, a recombinant vaccinia virus encoding bacteriophage T7 RNA polymerase. During incubation, the gene of interest is transcribed with high efficiency by T7 RNA polymerase. For large-scale work, protocols are provided for insertion of the p(T7)-regulated gene into a second recombinant vaccinia virus by homologous recombination and subsequent coinfection with vTF7-3 into cells grown in suspension or for direct transfection into OST7-1 cells (a stable cell line that constitutively expresses the T7 RNA polymerase). Expressed protein is then analyzed by pulse-labeling and purified. One new development to this vaccinia virus/T7 RNA polymerase hybrid expression system described here is the VOTE inducible expression system, which eliminates the need to use two recombinant viruses or a special cell line.

Analysis of the monkeypox virus genome

Monkeypox virus (MPV) belongs to the orthopoxvirus genus of the family Poxviridae, is endemic in parts of Africa, and causes a human disease that resembles smallpox. The 196,858-bp MPV genome was analyzed with regard to structural features and open reading frames. Each end of the genome contains an identical but oppositely oriented 6379-bp terminal inverted repetition, which similar to that of other orthopoxviruses, includes a putative telomere resolution sequence and short tandem repeats. Computer-assisted analysis was used to identify 190 open reading frames containing >/=60 amino acid residues. Of these, four were present within the inverted terminal repetition. MPV contained the known essential orthopoxvirus genes but only a subset of the putative immunomodulatory and host range genes. Sequence comparisons confirmed the assignment of MPV as a distinct species of orthopoxvirus that is not a direct ancestor or a direct descendent of variola virus, the causative agent of smallpox.