Nausea-induced suppression of feeding is mediated by central amygdala Dlk1-expressing neurons

The motivation to eat is suppressed by satiety and aversive stimuli such as nausea. The neural circuit mechanisms of appetite suppression by nausea are not well understood. Pkcδ neurons in the lateral subdivision of the central amygdala (CeA) suppress feeding in response to satiety signals and nausea. Here, we characterized neurons enriched in the medial subdivision (CeM) of the CeA marked by expression of Dlk1. CeADlk1 neurons are activated by nausea, but not satiety, and specifically suppress feeding induced by nausea. Artificial activation of CeADlk1 neurons suppresses drinking and social interactions, suggesting a broader function in attenuating motivational behavior. CeADlk1 neurons form projections to many brain regions and exert their anorexigenic activity by inhibition of neurons of the parabrachial nucleus. CeADlk1 neurons are inhibited by appetitive CeA neurons, but also receive long-range monosynaptic inputs from multiple brain regions. Our results illustrate a CeA circuit that regulates nausea-induced feeding suppression.

Empowering γδ T-cell functionality with vitamin C

Vitamin C (ascorbic acid) is a potent antioxidant and a cofactor for various enzymes including histone demethylases and methylcytosine dioxygenases. Vitamin C also exerts direct cytotoxicity toward selected tumor cells including colorectal carcinoma. Moreover, vitamin C has been shown to impact immune cell differentiation at various levels including maturation and/or functionality of T cells and their progenitors, dendritic cells, B cells, and NK cells. γδ T cells have recently attracted great interest as effector cells for cell-based cancer immunotherapy, due to their HLA-independent recognition of a large variety of tumor cells. While γδ T cells can thus be also applied as an allogeneic off-the-shelf product, it is obvious that the effector function of γδ T cells needs to be optimized to ensure the best possible clinical efficacy. Here we review the immunomodulatory mechanisms of vitamin C with a special focus on how vitamin C enhances the effector function of γδ T cells. We also discuss future directions of how vitamin C can be used in the clinical setting to boost the efficacy of adoptive cell therapies.

γδ T cell-mediated cytotoxicity against patient-derived healthy and cancer cervical organoids

Cervical cancer is a leading cause of death among women globally, primarily driven by high-risk papillomaviruses. However, the effectiveness of chemotherapy is limited, underscoring the potential of personalized immunotherapies. Patient-derived organoids, which possess cellular heterogeneity, proper epithelial architecture and functionality, and long-term propagation capabilities offer a promising platform for developing viable strategies. In addition to αβ T cells and natural killer (NK) cells, γδ T cells represent an immune cell population with significant therapeutic potential against both hematologic and solid tumours. To evaluate the efficacy of γδ T cells in cervical cancer treatment, we generated patient-derived healthy and cancer ectocervical organoids. Furthermore, we examined transformed healthy organoids, expressing HPV16 oncogenes E6 and E7. We analysed the effector function of in vitro expanded γδ T cells upon co-culture with organoids. Our findings demonstrated that healthy cervical organoids were less susceptible to γδ T cell-mediated cytotoxicity compared to HPV-transformed organoids and cancerous organoids. To identify the underlying pathways involved in this observed cytotoxicity, we performed bulk-RNA sequencing on the organoid lines, revealing differences in DNA-damage and cell cycle checkpoint pathways, as well as transcription of potential γδ T cell ligands. We validated these results using immunoblotting and flow cytometry. We also demonstrated the involvement of BTN3A1 and BTN2A1, crucial molecules for γδ T cell activation, as well as differential expression of PDL1/CD274 in cancer, E6/E7+ and healthy organoids. Interestingly, we observed a significant reduction in cytotoxicity upon blocking MSH2, a protein involved in DNA mismatch-repair. In summary, we established a co-culture system of γδ T cells with cervical cancer organoids, providing a novel in vitro model to optimize innovative patient-specific immunotherapies for cervical cancer.

Evaluating the cost implications of integrating SARS-CoV-2 genome sequencing for infection prevention and control investigation of nosocomial transmission within hospitals

BACKGROUND

The COG-UK hospital-onset COVID-19 infection (HOCI) trial evaluated the impact of SARS-CoV-2 whole-genome sequencing (WGS) on acute infection, prevention, and control (IPC) investigation of nosocomial transmission within hospitals.

AIM

To estimate the cost implications of using the information from the sequencing reporting tool (SRT), used to determine likelihood of nosocomial infection in IPC practice.

METHODS

A micro-costing approach for SARS-CoV-2 WGS was conducted. Data on IPC management resource use and costs were collected from interviews with IPC teams from 14 participating sites and used to assign cost estimates for IPC activities as collected in the trial. Activities included IPC-specific actions following a suspicion of healthcare-associated infection (HAI) or outbreak, as well as changes to practice following the return of data via SRT.

FINDINGS

The mean per-sample costs of SARS-CoV-2 sequencing were estimated at £77.10 for rapid and £66.94 for longer turnaround phases. Over the three-month interventional phases, the total management costs of IPC-defined HAIs and outbreak events across the sites were estimated at £225,070 and £416,447, respectively. The main cost drivers were bed-days lost due to ward closures because of outbreaks, followed by outbreak meetings and bed-days lost due to cohorting contacts. Actioning SRTs, the cost of HAIs increased by £5,178 due to unidentified cases and the cost of outbreaks decreased by £11,246 as SRTs excluded hospital outbreaks.

CONCLUSION

Although SARS-CoV-2 WGS adds to the total IPC management cost, additional information provided could balance out the additional cost, depending on identified design improvements and effective deployment.

First Dark Matter Search with Nuclear Recoils from the XENONnT Experiment

We report on the first search for nuclear recoils from dark matter in the form of weakly interacting massive particles (WIMPs) with the XENONnT experiment, which is based on a two-phase time projection chamber with a sensitive liquid xenon mass of 5.9 ton. During the (1.09±0.03)  ton yr exposure used for this search, the intrinsic ^{85}Kr and ^{222}Rn concentrations in the liquid target are reduced to unprecedentedly low levels, giving an electronic recoil background rate of (15.8±1.3)  events/ton yr keV in the region of interest. A blind analysis of nuclear recoil events with energies between 3.3 and 60.5 keV finds no significant excess. This leads to a minimum upper limit on the spin-independent WIMP-nucleon cross section of 2.58×10^{-47}  cm^{2} for a WIMP mass of 28  GeV/c^{2} at 90% confidence level. Limits for spin-dependent interactions are also provided. Both the limit and the sensitivity for the full range of WIMP masses analyzed here improve on previous results obtained with the XENON1T experiment for the same exposure.

Searching for Heavy Dark Matter near the Planck Mass with XENON1T

Multiple viable theoretical models predict heavy dark matter particles with a mass close to the Planck mass, a range relatively unexplored by current experimental measurements. We use 219.4 days of data collected with the XENON1T experiment to conduct a blind search for signals from multiply interacting massive particles (MIMPs). Their unique track signature allows a targeted analysis with only 0.05 expected background events from muons. Following unblinding, we observe no signal candidate events. This Letter places strong constraints on spin-independent interactions of dark matter particles with a mass between 1×10^{12} and 2×10^{17}  GeV/c^{2}. In addition, we present the first exclusion limits on spin-dependent MIMP-neutron and MIMP-proton cross sections for dark matter particles with masses close to the Planck scale.

Transcriptomics reveals amygdala neuron regulation by fasting and ghrelin thereby promoting feeding

The central amygdala (CeA) consists of numerous genetically defined inhibitory neurons that control defensive and appetitive behaviors including feeding. Transcriptomic signatures of cell types and their links to function remain poorly understood. Using single-nucleus RNA sequencing, we describe nine CeA cell clusters, of which four are mostly associated with appetitive and two with aversive behaviors. To analyze the activation mechanism of appetitive CeA neurons, we characterized serotonin receptor 2a (Htr2a)-expressing neurons (CeA^Htr2a) that comprise three appetitive clusters and were previously shown to promote feeding. In vivo calcium imaging revealed that CeA^Htr2a neurons are activated by fasting, the hormone ghrelin, and the presence of food. Moreover, these neurons are required for the orexigenic effects of ghrelin. Appetitive CeA neurons responsive to fasting and ghrelin project to the parabrachial nucleus (PBN) causing inhibition of target PBN neurons. These results illustrate how the transcriptomic diversification of CeA neurons relates to fasting and hormone-regulated feeding behavior.

Impact of supplementary air filtration on aerosols and particulate matter in a UK hospital ward: a case study

BACKGROUND

Aerosol spread of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a major problem in hospitals, leading to an increase in supplementary high-efficiency particulate air filtration aimed at reducing nosocomial transmission. This article reports a natural experiment that occurred when an air cleaning unit (ACU) on a medicine for older people ward was switched off accidentally while being commissioned.

AIM

To assess aerosol transport within the ward and determine whether the ACU reduced airborne particulate matter (PM) levels.

METHODS

An ACU was placed in a ward comprising two six-bedded bays plus three single-bed isolation rooms which had previously experienced several outbreaks of coronavirus disease 2019. During commissioning, real-time measurements of key indoor air quality parameters (PM1-10, CO2, temperature and humidity) were collected from multiple sensors over 2 days. During this period, the ACU was switched off accidentally for approximately 7 h, allowing the impact of the intervention on PM to be assessed.

FINDINGS

The ACU reduced the PM counts considerably (e.g. PM1 65.5-78.2%) throughout the ward (P<0.001 all sizes), with positive correlation found for all PM fractions and CO2 (r=0.343-0.817; all P<0.001). PM counts rose/fell simultaneously when the ACU was off, with correlation of PM signals from multiple locations (e.g. r=0.343-0.868; all P<0.001) for particulates <1 μm).

CONCLUSION

Aerosols migrated rapidly between the various ward subcompartments, suggesting that social distancing alone cannot prevent nosocomial transmission of SARS-CoV-2 as this fails to mitigate longer-range (>2 m) transmission. The ACU reduced PM levels considerably throughout the ward space, indicating its potential as an effective intervention to reduce the risk posed by infectious airborne particles.

331 THE USE OF BODY MASS INDEX IN PREDICTING ORTHOSTATIC HYPOTENSION IN OLDER ADULTS

Background

The presence of Orthostatic Hypotension (OH) is known to be associated with an increased mortality risk. Previous Irish research has shown that elevated Body Mass Index (BMI) may be protective against OH, with overweight and obese patients having significantly smaller Systolic Blood Pressure (SBP) drops during Head-Up-Tilt (HUT) Testing.

Methods

Demographics, including age, height and weight, were obtained retrospectively from all head up tilt testing performed in a tertiary Irish hospital between 2000 and 2021. All incomplete records were excluded. A total of 4,717 patients were analysed. Linear regression models were used to examine the relationship between BMI and change in tilt SBP.

Results

2,089 males and 2,628 females over the age of 60 years old were examined. The mean age is 77 years ± 7.8 (S.D.), with majority (51.5%) of the cohort overweight or obese. 69.7% of individuals demonstrated OH. The mean change in tilt SBP was –7mmHg in the underweight and healthy weight group, and –10mmHg in the overweight or obese group. The linear regression model established that BMI significantly predicted a change in tilt SBP (beta=0.394, 95% CI: 0.235 to 0.554, p&lt;0.001), but remains a poor predictive variable (R2=0.004) for this cohort. This correlation was similar for both genders (male: r=0.08, female: r=0.07).

Conclusion

Our findings confirmed a correlation between BMI and its predictive impact on OH in older adults. Future studies should explore targeted populations with multivariate analysis, taking into consideration age and gender, to reduce the heterogeneity of data.

220 RELATIONSHIP BETWEEN HEIGHT AND SYSTOLIC BLOOD PRESSURE IN OLDER ADULTS

Background

Hypertension is common amongst older adults in Ireland and is a major risk factor for both ischaemic and haemorrhagic stroke. Several studies have investigated the relationship between height and hypertension, however results have been inconsistent. In our Irish tertiary hospital patients undergoing tilt table testing have resting blood pressure measured prior to the test, and height recorded. Our aim was to assess whether there is a relationship between height and resting Systolic Blood Pressure (SBP) in patients aged over 60 years.

Methods

All tilt table test results between 2000 and 2021 in a single centre were reviewed retrospectively, collecting data on age, height and resting SBP. Any incomplete records were excluded, as were those from patients under 60 years old. Linear regression modelling was used to assess relationship between height and resting SBP.

Results

A total of 4,729 complete records were included for patients over 60 years old. 2630 (61.5%) of the patients were female. Mean age was 77 ± 7.8 years. 57.7% patients had either an elevated resting systolic and/or diastolic BP ≥130/80 and 28.4% ≥140/90. The linear regression model established that while height could be used to predict resting systolic blood pressure (beta=-0.166, 95% CI: –0.219 to –0.113, p&lt;0.001), height only accounted for 0.8% of variability in resting SBP (R2 = 0.008).

Conclusion

Our large dataset establishes an association but no meaningful causation between height and resting systolic blood pressure. Current antihypertensive treatment was not recorded, which may have affected the results. Future studies will include further multivariate analysis accounting for antihypertensive use and other factors that may impact hypertension such as age, weight and gender.

353 FACTORS ASSOCIATED WITH ADVERSE OUTCOMES IN OLDER ADULTS DIRECTLY DISCHARGED FROM THE EMERGENCY DEPARTMENT

Background

Older adults attend the Emergency Department (ED) frequently. Over 40% are directly discharged from the ED. The risk of adverse outcomes is high following discharge including unplanned ED return, institutionalisation, and mortality. The purpose of this study was to highlight factors that predict these adverse outcomes.

Methods

A secondary analysis was completed of SOAED (a prospective cohort study examining screening instruments to predict adverse outcomes for undifferentiated older adults attending the ED) and OPTIMEND (randomised control trial examining the effectiveness of an intervention by a team of Health and Social Care Professionals along with usual care and compared this to standard ED care alone). Inclusion criteria were adults aged 65 years and over presenting to ED at a University Teaching Hospital with medical complaints and a Manchester Triage System category 2–5.

Results

Three-hundred and nine patients were discharged directly from ED (mean age 80 years; 58% female). 96 patients re-attended ED within 6 months. 66 patients were re-hospitalised within 6 months. 16 patients died within six months of discharge. 63% of the discharged patients screened positive for frailty measured by PRISMA-7 (3 or more). Relative risk ratio analysis confirmed that the risk of revisiting a hospital was 1.241 times for patients that scored frail compared to those who scored not frail. The risk of mortality was 1.075 times for patients that scored frail compared to those who scored not frail. The risk of being admitted to a nursing home was 1.146 times for patients that scored frail compared to those who scored not frail.

Conclusion

Older people have a high ED re-attendance rate of 31% after an index visit. Frailty (scored on PRISMA-7) is a significant predictor of adverse outcomes. Focused screening and intervention for frail patients who attend the ED should be a priority.

Signal strength of STING activation determines cytokine plasticity and cell death in human monocytes

The cyclic GMP-AMP synthase (cGAS)/stimulator of interferon genes (STING) pathway is a cytosolic sensor of microbial and host-derived DNA and plays a key role in innate immunity. Activation of STING by cyclic dinucleotide (CDN) ligands in human monocytes induces a type I interferon response and production of pro-inflammatory cytokines associated with the induction of massive cell death. In this study we have re-evaluated the effect of signal strength of STING activation on the cytokine plasticity of human monocytes. CDN (2'3'c-GAMP) and non-CDN (diABZI, MSA-2) STING ligands in the range of EC₅₀ concentrations (15 μM 2'3'c-GAMP, 100 nM diABZI, 25 μM MSA-2) induced IFN-β, IP-10, and large amounts of IL-1β and TNF-α, but no IL-10 or IL-19. Interestingly, LPS-induced production of IL-10 and IL-19 was abolished in the presence of diABZI or MSA-2, whereas IL-1β and TNF-α were not inhibited. Surprisingly, we observed that tenfold lower (MSA-2, i.e. 2.5 μM) or 100-fold lower (diABZI, i.e. 1 nM) concentrations strongly stimulated secretion of anti-inflammatory IL-10 and IL-19, but little of IL-1β and TNF-α. Induction of IL-10 was associated with up-regulation of PRDM1 (Blimp-1). While cytokine secretion stimulated by the higher concentrations was accompanied by apoptosis as shown by cleavage of caspase-3 and PARP-1, the low concentrations did not trigger overt cell death yet induced cleavage of gasdermin-D. Our results reveal a previously unrecognized plasticity of human monocytes in their signal strength-dependent production of pro- versus anti-inflammatory cytokines upon STING activation.

Search for New Physics in Electronic Recoil Data from XENONnT

We report on a blinded analysis of low-energy electronic recoil data from the first science run of the XENONnT dark matter experiment. Novel subsystems and the increased 5.9 ton liquid xenon target reduced the background in the (1, 30) keV search region to (15.8±1.3)  events/(ton×year×keV), the lowest ever achieved in a dark matter detector and ∼5 times lower than in XENON1T. With an exposure of 1.16 ton-years, we observe no excess above background and set stringent new limits on solar axions, an enhanced neutrino magnetic moment, and bosonic dark matter.

Epidemiology and impact of frailty in patients with atrial fibrillation in Europe

BACKGROUND

Frailty is a medical syndrome characterised by reduced physiological reserve and increased vulnerability to stressors. Data regarding the relationship between frailty and atrial fibrillation (AF) are still inconsistent.

OBJECTIVES

We aim to perform a comprehensive evaluation of frailty in a large European cohort of AF patients.

METHODS

A 40-item frailty index (FI) was built according to the accumulation of deficits model in the AF patients enrolled in the ESC-EHRA EORP-AF General Long-Term Registry. Association of baseline characteristics, clinical management, quality of life, healthcare resources use and risk of outcomes with frailty was examined.

RESULTS

Among 10,177 patients [mean age (standard deviation) 69.0 (11.4) years, 4,103 (40.3%) females], 6,066 (59.6%) were pre-frail and 2,172 (21.3%) were frail, whereas only 1,939 (19.1%) were considered robust. Baseline thromboembolic and bleeding risks were independently associated with increasing FI. Frail patients with AF were less likely to be treated with oral anticoagulants (OACs) (odds ratio 0.70, 95% confidence interval 0.55-0.89), especially with non-vitamin K antagonist OACs and managed with a rhythm control strategy, compared with robust patients. Increasing frailty was associated with a higher risk for all outcomes examined, with a non-linear exponential relationship. The use of OAC was associated with a lower risk of outcomes, except in patients with very/extremely high frailty.

CONCLUSIONS

In this large cohort of AF patients, there was a high burden of frailty, influencing clinical management and risk of adverse outcomes. The clinical benefit of OAC is maintained in patients with high frailty, but not in very high/extremely frail ones.

Analysis of the Seasonal Fluctuation of γδ T Cells and Its Potential Relation with Vitamin D3

In addition to its role in bone metabolism, vitamin D3 exerts immunomodulatory effects and has been proposed to contribute to seasonal variation of immune cells. This might be linked to higher vitamin D3 levels in summer than in winter due to differential sun exposure. γδ T cells comprise a numerically small subset of T cells in the blood, which contribute to anti-infective and antitumor immunity. We studied the seasonal fluctuation of γδ T cells, the possible influence of vitamin D3, and the effect of the active metabolite 1α,25(OH)2D3 on the in vitro activation of human γδ T cells. In a retrospective analysis with 2625 samples of random blood donors, we observed higher proportions of γδ T cells in winter when compared with summer. In a prospective study over one year with a small cohort of healthy adults who did or did not take oral vitamin D3 supplementation, higher proportions of γδ T cells were present in donors without oral vitamin D3 uptake, particularly in spring. However, γδ T cell frequency in blood did not directly correlate with serum levels of 25(OH)D3. The active metabolite 1α,25(OH)2D3 inhibited the in vitro activation of γδ T cells at the level of proliferation, cytotoxicity, and interferon-γ production. Our study reveals novel insights into the seasonal fluctuation of γδ T cells and the immunomodulatory effects of vitamin D3.

Stimulatory and inhibitory activity of STING ligands on tumor-reactive human gamma/delta T cells

Ligands for Stimulator of Interferon Genes (STING) receptor are under investigation as adjuvants in cancer therapy. Multiple effects have been described, including induction of immunogenic cell death and enhancement of CD8 T-cell mediated anti-tumor immunity. However, the potential effects of STING ligands on activation and effector functions of tumor-reactive human γδ T cells have not yet been investigated. We observed that cyclic dinucleotide as well as novel non-dinucleotide STING ligands diABZI and MSA-2 co-stimulated cytokine induction in Vδ2 T cells within peripheral blood mononuclear cells but simultaneously inhibited their proliferative expansion in response to the aminobisphosphonate Zoledronate and to γδ T-cell specific phosphoantigen. In purified γδ T cells, STING ligands co-stimulated cytokine induction but required the presence of monocytes. STING ligands strongly stimulated IL-1β and TNF-α secretion in monocytes and co-stimulated cytokine induction in short-term expanded Vδ2 γδ T-cell lines. Simultaneously, massive cell death was triggered in both cell populations. Activation of STING as revealed by TBK1/IRF3 phosphorylation and IP-10 secretion varied among STING-expressing tumor cells. STING ligands modulated tumor cell killing by Vδ2 T cells as analyzed in Real-Time Cell Analyzer to variable degree, depending on the tumor target and time course kinetics. Our study reveals complex regulatory effects of STING ligands on human γδ T cells in vitro. These results help to define conditions where STING ligands might boost the efficacy of γδ T cell immunotherapy in vivo.

FLRT3 Marks Direction-Selective Retinal Ganglion Cells That Project to the Medial Terminal Nucleus

The mammalian retina extracts a multitude of diverse features from the visual scene such as color, contrast, and direction of motion. These features are transmitted separately to the brain by more than 40 different retinal ganglion cell (RGC) subtypes. However, so far only a few genetic markers exist to fully characterize the different RGC subtypes. Here, we present a novel genetic Flrt3-CreERT2 knock-in mouse that labels a small subpopulation of RGCs. Using single-cell injection of fluorescent dyes in Flrt3 positive RGCs, we distinguished four morphological RGC subtypes. Anterograde tracings using a fluorescent Cre-dependent Adeno-associated virus (AAV) revealed that a subgroup of Flrt3 positive RGCs specifically project to the medial terminal nucleus (MTN), which is part of the accessory optic system (AOS) and is essential in driving reflex eye movements for retinal image stabilization. Functional characterization using ex vivo patch-clamp recordings showed that the MTN-projecting Flrt3 RGCs preferentially respond to downward motion in an ON-fashion. These neurons distribute in a regular pattern and most of them are bistratified at the level of the ON and OFF bands of cholinergic starburst amacrine cells where they express the known ON-OFF direction-selective RGC marker CART. Together, our results indicate that MTN-projecting Flrt3 RGCs represent a new functionally homogeneous AOS projecting direction-selective RGC subpopulation.

Vitamin C, From Supplement to Treatment: A Re-Emerging Adjunct for Cancer Immunotherapy?

Vitamin C (VitC), in addition to its role as a general antioxidant, has long been considered to possess direct anti-cancer activity at high doses. VitC acts through oxidant and epigenetic mechanisms, which at high doses can exert direct killing of tumor cells in vitro and delay tumor growth in vivo. Recently, it has also been shown that pharmacologic-dose VitC can contribute to control of tumors by modulating the immune system, and studies have been done interrogating the role of physiologic-dose VitC on novel adoptive cellular therapies (ACTs). In this review, we discuss the effects of VitC on anti-tumor immune cells, as well as the mechanisms underlying those effects. We address important unanswered questions concerning both VitC and ACTs, and outline challenges and opportunities facing the use of VitC in the clinical setting as an adjunct to immune-based anti-cancer therapies.

Modulatory Actions of the Glycine Receptor β Subunit on the Positive Allosteric Modulation of Ethanol in α2 Containing Receptors

Alpha1-containing glycine receptors (GlyRs) are major mediators of synaptic inhibition in the spinal cord and brain stem. Recent studies reported the presence of α2-containing GlyRs in other brain regions, such as nucleus accumbens and cerebral cortex. GlyR activation decreases neuronal excitability associated with sensorial information, motor control, and respiratory functions; all of which are significantly altered during ethanol intoxication. We evaluated the role of β GlyR subunits and of two basic amino acid residues, K389 and R390, located in the large intracellular loop (IL) of the α2 GlyR subunit, which are important for binding and functional modulation by Gβγ, the dimer of the trimeric G protein conformation, using HEK-293 transfected cells combined with patch clamp electrophysiology. We demonstrate a new modulatory role of the β subunit on ethanol sensitivity of α2 subunits. Specifically, we found a differential allosteric modulation in homomeric α2 GlyRs compared with the α2β heteromeric conformation. Indeed, while α2 was insensitive, α2β GlyRs were substantially potentiated by ethanol, GTP-γ-S, propofol, Zn²⁺ and trichloroethanol. Furthermore, a Gβγ scavenger (ct-GRK2) selectively attenuated the effects of ethanol on recombinant α2β GlyRs. Mutations in an α2 GlyR co-expressed with the β subunit (α2AAβ) specifically blocked ethanol sensitivity, but not propofol potentiation. These results show a selective mechanism for low ethanol concentration effects on homomeric and heteromeric conformations of α2 GlyRs and provide a new mechanism for ethanol pharmacology, which is relevant to upper brain regions where α2 GlyRs are abundantly expressed.

Airborne protection for staff is associated with reduced hospital-acquired COVID-19 in English NHS Trusts

Introduction

The rate of hospital-acquired coronavirus disease 2019 has reduced from 14.3% to 4.2% over the last year, but substantial differences still exist between English National Health Service (NHS) hospital trusts.

Methods

This study assessed rates of hospital-acquired infection (HAI), comparing NHS hospital trusts using airborne respiratory protection (e.g. FFP3 masks) for all staff, as a marker of measures to reduce airborne spread, with NHS hospital trusts using mainly droplet precautions (e.g. surgical masks).

Results/discussion

The use of respiratory protective equipment was associated with a 33% reduction in the odds of HAI in the Delta wave, and a 21% reduction in the odds of HAI in the Alpha wave (P<0.00001). It is recommended that all hospitals should prioritize airborne mitigation.

233 BISPHOSPHONATES: ANOTHER COMPLEX DRUG TO PRESCRIBE

Background

Bisphosphonates provide effective treatment for osteoporosis. They accumulate a bone reservoir lasting for 3 years and beyond. The 2021 NICE guidelines recommend a medication review and a ‘drug holiday’ after 5 years of oral bisphosphonate therapy for low-fracture risk patients. Continuing treatment for high risk individuals is advised: age=/&gt;75, previous hip or vertebral fracture, one or more fractures during treatment, recent DEXA scan with T score =/&lt;−2.5, and/or current treatment with oral glucocorticoids. This retrospective audit aimed to assess compliance with NICE guidelines in a primary care setting.

Methods

Data were collected using the Health One online medical record system in an urban general practice. Inclusion criteria: all patients =/&gt; 65 years old, prescribed oral bisphosphonate therapy for osteoporosis for &gt;5 years. Exclusion criteria: deceased, did not attend clinic &gt;1 year, patients on bisphosphonate treatment for conditions other than osteoporosis.

Results

137 patients with a history of bisphosphonate therapy were identified. 76 patients were on bisphosphonate treatment for greater than 5 years. Of the 76 patients, 33 were classified as low-fracture risk and appropriately commenced a drug holiday, while 22 correctly remained on bisphosphonates due to a high fracture risk. The remaining 21 patients inappropriately continued therapy without receiving a medication review, repeat DEXA or fracture-risk assessment.

Conclusion

One third of patients on bisphosphonates beyond 5 years were not assessed for a drug holiday. The aim of a bisphosphonate ‘drug holiday’ is to reduce poly-pharmacy and prevent rare but serious long-term adverse events (such as atypical fractures, osteonecrosis of the jaw, gastric cancer and atrial fibrillation). Factors which had an impact on inappropriate prescribing should be assessed. Incorporating computer-based prescribing alerts could support safe prescribing practices.

241 IMPLEMENTATION OF AN INTRACEREBRAL CEREBRAL HAEMORRHAGE CARE BUNDLE

Background

Mortality for Intracerebral haemorrhage (ICH) is 31% (Irish National Audit Stroke, 2019). An ICH care bundle focusing on acute anticoagulation reversal, blood pressure lowering, and a neurosurgical care pathway was associated with improved survival. Translating evidence-based medicine into clinical practice is challenging. The aim of this study was to determine feasibility and outcomes of implementation of a care bundle.

Methods

An ICH care bundle was developed using an iterative process involving expert stakeholder review of the evidence-based literature. A pre-and-post quasi-experimental research design was employed to evaluate this intervention. Baseline data were collected before implementation (January 2016-June 2018). Implementation took place in a staged manner in a single university teaching hospital with multiple ‘Plan Do Study Act cycles’ (June 2018 to January 2021). Data on compliance, process measures and outcomes were collected.

Results

Systolic blood pressure (first 24-hours) and anticoagulant reversal were significantly better controlled post-implementation (χ2 (1, N = 91) = 5.34, P = 0.02), (χ2 (1, N = 25) = 5.85, P = 0.016), respectively. DNAR orders were significantly lower in the post-implementation group (χ2 (1, N = 25) = 5.85, P = 0.029). However, ‘Do Not Actively Resuscitate’ status did not significantly differ when accounting for low GCS as a surrogate measure for poor prognosis (χ2 (1, N = 34) = 0.00, P = 0.966). Modified Rankin Scale on discharge did not differ significantly pre-and-post-implementation (z = −0.075, P = 0.94). A greater proportion of patients survived in the post-implementation group; however, this was not statistically significant (χ2 (1, N = 133) = 0.77, P = 0.38). Length of stay significantly increased post implementation.

Conclusion

An ICH care bundle was developed based on expert stakeholder feedback. The feasibility of implementing this bundle of care was demonstrated in a real-world clinical practice setting. A cluster-randomized trial or a large registry study is the next step to evaluate the overall impact of this care bundle on patient outcomes.

247 BENCHMARKING STROKE SERVICES TO INFORM A QUALITY IMPROVEMENT INIAITIVE

Background

Stroke is a leading cause of death and disability in Ireland. Continuous audit and quality improvement is essential in the delivery of stroke care where the evidence basis is constantly changing. This helps to ensure the delivery of high quality stroke care and compliance with evidenced based guidelines. We aimed to assess stroke care at an Irish university teaching hospital.

Methods

Patients with a HIPE discharge diagnosis of Cerebral Infarction or Cerebral Haemorrhage (1st January-31st December 2019) were identified through both the HIPE database and the institutional Stroke Portal. Data was benchmarked against national (Irish National Audit of Stroke 2019) and international (6th SSNAP Annual Report; American Heart Association, 2013) practice and used to inform a quality improvement strategy.

Results

419 patients were included (56.6% male, median 57 years). 75.9% were aged 65 years or older. We compared favourably with Irish National Audit of Stoke national indicators on the following: thrombolysis rates-10%; median door to needle time-60 mins; stroke unit admissions- 78.5%; median duration of symptoms- 3 hours 6 minutes; swallow assessment- 81.1%; in-patient mortality- 10.5%; rates of institutionalisation- 3.8%. Areas identified for improvement were: thrombectomy rates- 1.9%; median length of stay- 12 days; door to imaging time- median 104 minutes; mood screening- 11.5%.

Conclusion

International and national data is a useful benchmark against which local hospitals can assess the quality of their service. By completing this quality improvement initiative we identified areas to target resources in our centre, including mood screening, swallow screening, thrombectomy rates, length of stay and time to neuroimaging. An ongoing quality improvement process using ‘PDSA’ methodology is being carried out with an annual audit to monitor progress.

235 THROMBOLYSIS DOSING AND WEIGHT ESTIMATION IN ACUTE STROKE: A SINGLE CENTRE AUDIT

Background

Stroke is a leading cause of death and disability. Thrombolysis with intravenous (IV) alteplase is the mainstay management of ischaemic stroke. It has a narrow therapeutic window with a high potential for adverse outcomes such as intracranial haemorrhage. The efficacy of alteplase is time and dose dependent with weight-based dosing. National clinical guidelines recommend a dose of 0.9 mg/kg, up to a maximum of 90 mg. (Irish Heart Foundation Council for Stroke 2015). In most hospitals in Ireland however, patients are not weighed prior to thrombolysis. Time pressure and lack of available suitable equipment are factors.

Methods

This retrospective clinical audit evaluated the dosing of alteplase, estimated and actual weight for a convenience sample of stroke thrombolysis patients treated between 2016–2020 at an Irish University Teaching Hospital.

Results

107 patients were audited (62 males, 45 females). Actual and estimated weights were available in 92/107. Weight was not documented (n = 15) due to severe stroke/palliative management (n = 6) or omission (n = 9). 21% (19/92) received the correct dose of 0.9 mg/kg. A further 54% (50/92) received a dose within the range of 0.81–0.99 mg/kg (±10%). 25% received a dose outside this range (&gt; ± 10%). 11% (10/92) were under-thrombolysed and 14% (13/92) over-thrombolysed. 17/92 patients had an intracranial haemorrhage. 35% (n = 6/17) of patients who had an intracranial haemorrhage received a higher dose of thrombolysis (&gt;10%).

Conclusion

A quarter of patients received inappropriate dosing of alteplase that was outside the range of ±10% of 0.9 mg/kg. While stroke thrombolysis must be completed urgently, an accurate weight should be determined to avoid errors in dosing. A process evaluation of stroke thrombolysis would provide information on how best to incorporate an objective means of weight measurement without delaying treatment.

236 PREDICTORS OF ADVERSE OUTCOMES IN OLDER PATIENTS DISCHARGED DIRECTLY FROM THE EMERGENCY DEPARTMENT

Background

Over 40% of older patients are discharged directly from the Emergency Department (ED) and this cohort is at increased risk of adverse outcomes.

The purpose of this study was to explore the factors that predict future adverse outcomes in this cohort to inform practice, resource planning and policy.

Methods

A secondary analysis of the OPTIMEND, a single-centre, randomized-controlled trial was completed. OPTIMEND examined the effectiveness of an intervention by a team of Health and Social Care Professionals along with usual care and compared this to standard ED care alone (Dec 2018-May 2019). The inclusion criteria were adults aged 65 years and over presenting to the ED at a University Teaching Hospital with medical complaints and a Manchester Triage System category 2–5.

Results

220 patients were included (median age 79 years; 62% female). Median length of stay in ED was 5.5 hrs. 70 patients re-attended the ED within 6 months with 43 re-hospitalised within 6 months. 9 patients died within six months of discharge.

Multivariant logistic regression was completed. Age was the only independent predictor of mortality within six months of discharge {Odds Ratio (OR) 1.15, p = 0.044}. Past hospitalisation (&lt;6 months) was associated with a lower likelihood of ED re-attendance, and rehospitalization within six months of discharge (OR: 0.452 p = 0.022; OR:0.442, p = 0.046; respectively). Clinical Frailty Score was associated with a significantly higher likelihood of rehospitalization (OR:1.48, p = 0.031) but not with ED revisits (OR: 1.235, p = 0.165).

Conclusion

Older people have a high ED re-attendance rate of 33% after an index visit with 20% hospitalized subsequently. Frailty is a significant predictor of rehospitalisation. Rapid and targeted intervention for frail patients who reattend the ED should be a priority for the integrated care program to enhance admission avoidance.

234 THE IMPACT OF OLDER AGE ON CLINICAL OUTCOMES DURING THE FIRST WAVE OF THE COVID-19 PANDEMIC

Background

Severe acute respiratory coronavirus 2 (SARS-CoV-2) was first recorded in Ireland in February 2020. Several studies have explored the association between age and SARS-CoV-2, showing that there were poorer outcomes in older people. Our objective was to evaluate the impact of age on outcomes such as hospital length of stay, mortality, and re-hospitalisation.

Methods

We performed a single-centre, retrospective observational cohort study, using an electronic microbiology database of recorded index admissions of SARS-CoV-2 positive patients aged 65 years and older during SARS-CoV-2 wave one (March 1^st to May 31^st 2020). PCR testing of nasopharyngeal and/or sputum samples was used to confirm positivity. Our clinical outcomes measured included hospital length of stay, mortality and re-admission rate within 6 months.

Results

153 patients 65 years and above were admitted. The male to female ratio was 1.3 with 90% admitted medically. 79 patients were aged between 65–79 years; 84 patients ≥80 years; and 12 patients ≥90 years. Mortality was 25%, 31% and 42%, respectively. Median length of stay remained 14 days for ages 65–89 rising to 17.5 days for those ≥90 years. Re-hospitalisation rates at 6 months were similar for ages 65–79 and 89–89 years at 42% and 40%, respectively. One patient (14%) over 90 years was re-hospitalised.

Conclusion

SARS-CoV-2 has disproportionately impacted on general medical services treating older hospitalised people. In our centre, mortality for patients ≥65 years was 28.1% which compared favourably with 35.6% internationally as outlined by Victor et al. (2020) based on Spanish data. Treatment of SARS-CoV-2 is not futile in older patients with 58% of nonagenarians and 69% of octogenarians surviving, however re-hospitalisation rates are high at 40%. A targeted approach to discharge support via integrated care may ameliorate this.

584 Novel Methods of Detecting Tumour Margins in Gastrointestinal Cancer Surgery

Aim

Gastrointestinal (GI) cancers account for 26% of global cancer incidence with prevalence projected to rise exponentially due to the ageing population and lifestyle choices. Surgical resection is the mainstay of treatment to remove the cancer in its entirety to achieve an R0 resection. Positive margins, when cancerous tissue has been left in situ, is associated with increased morbidity and mortality. Current margin assessment involves histopathological analysis, after resection of the specimen. Diffuse Reflectance Spectroscopy (DRS) and Hyperspectral Imaging (HSI) are novel imaging techniques that have the potential to provide real-time assessment of cancer margins intra-operatively to reduce the incidence of positive resection margins and improve patient outcomes. The aim of this review is to assess the current state of evidence for the use of novel imaging techniques in GI cancer margin assessment.

Method

A literature review was conducted of studies using DRS and HSI in GI cancers in adult patients, published from inception to October 2020.

Results

A total of 15 studies were analysed, nine of which used DRS and six used HSI and the majority of studies were performed ex-vivo. Current image acquisition techniques and processing algorithms vary greatly. The sensitivity and specificity of DRS ranged from 0.90-0.98 and 0.88-0.95 respectively and for HSI 0.63-0.98 and 0.69-0.98, respectively across five types of GI cancers.

Conclusions

DRS and HSI are novel imaging techniques, currently in their infancy but the outlook is promising. With further research focused on standardising methodology and in-vivo settings, DRS and HSI could transform intra-operative margin assessment in GI cancers.

Synaptic dysregulation and hyperexcitability induced by intracellular amyloid beta oligomers

Intracellular amyloid beta oligomer (iAβo) accumulation and neuronal hyperexcitability are two crucial events at early stages of Alzheimer's disease (AD). However, to date, no mechanism linking iAβo with an increase in neuronal excitability has been reported. Here, the effects of human AD brain-derived (h-iAβo) and synthetic (iAβo) peptides on synaptic currents and action potential firing were investigated in hippocampal neurons. Starting from 500 pM, iAβo rapidly increased the frequency of synaptic currents and higher concentrations potentiated the AMPA receptor-mediated current. Both effects were PKC-dependent. Parallel recordings of synaptic currents and nitric oxide (NO)-associated fluorescence showed that the increased frequency, related to pre-synaptic release, was dependent on a NO-mediated retrograde signaling. Moreover, increased synchronization in NO production was also observed in neurons neighboring those dialyzed with iAβo, indicating that iAβo can increase network excitability at a distance. Current-clamp recordings suggested that iAβo increased neuronal excitability via AMPA-driven synaptic activity without altering membrane intrinsic properties. These results strongly indicate that iAβo causes functional spreading of hyperexcitability through a synaptic-driven mechanism and offers an important neuropathological significance to intracellular species in the initial stages of AD, which include brain hyperexcitability and seizures.

Investigation and control of an outbreak due to a contaminated hospital water system, identified following a rare case of Cupriavidus pauculus bacteraemia

BACKGROUND

Cupriavidus pauculus is rare cause of clinical infection. We describe an outbreak of C. pauculus and other Gram-negative bacteraemias in a paediatric haemato-oncology unit secondary to a contaminated water supply and drainage system.

AIM

To describe the investigation and control measures implemented for a waterborne infection outbreak in a new build hospital.

METHODS

Extensive water testing from various points within the water system was undertaken. Taps, showerheads and components including flow straighteners underwent microbiological analysis. Drains were also swabbed. Surveillance for Gram-negative infections was established on the unit.

FINDINGS

Water testing revealed widespread contamination of the water and drainage system. Outlets were also heavily contaminated, including flow straighteners. Drains were found to have underlying structural abnormalities. Water testing enabled us to detect high-risk components within the water system such as the expansion vessels and outlets and the results assisted with hypotheses generation. Review of commissioning data and risk assessments revealed extensive risks present within the water system prior to and after hospital opening.

CONCLUSION

Careful design, adequate control measures and maintenance are essential for hospital water systems in order to prevent infections due to waterborne organisms. We discuss what can be learned from this incident with a view to future prevention.

Monocyte-dependent co-stimulation of cytokine induction in human γδ T cells by TLR8 RNA ligands

Human Vγ9Vδ2 T cells recognize pyrophosphates produced by microbes and transformed cells and play a role in anti-infective immunity and tumor surveillance. Toll-like receptors (TLR) are pattern recognition receptors in innate immune cells which sense microbial structures including nucleic acids. Given that γδ T cells are in clinical development for application in cellular cancer immunotherapy and TLR ligands have potent adjuvant activity, we investigated the co-stimulatory role of selected TLR ligands in γδ T-cell activation. Here we have used recently described RNA ligands for TLR7 and TLR8 together with Vγ9Vδ2 T-cell specific pyrophosphate antigens to analyze the rapid cytokine induction in Vδ2 T cells as well as the accessory cell requirements. While TLR8- as well as TLR7/8-specific RNA did not induce IFN-γ in Vδ2 T cells on their own, they provided strong co-stimulation for Vδ2 T cells within peripheral blood mononuclear cells in the presence of additional T-cell receptor activation. In contrast, TLR7 ligands were ineffective. Purified γδ T cells did not directly respond to TLR8 co-stimulation but required the presence of monocytes. Further experiments revealed a critical role of IL-1β and IL-18, and to a slightly lesser extent of IL-12p70, in the co-stimulation of Vδ2 T cells by TLR8 and TLR7/8 RNA ligands. Results of intracellular cytokine expression were validated by ELISA analysis of cytokines in cell culture supernatants. The cell context-dependent adjuvant activity of TLR8 and TLR7/8 RNA ligands described here might be important for the future optimization of γδ T-cell based cancer immunotherapy.

Investigation of two cases of Mycobacterium chelonae infection in haemato-oncology patients using whole-genome sequencing and a potential link to the hospital water supply

BACKGROUND

Haemato-oncology patients are at increased risk of infection from atypical mycobacteria such as Mycobacterium chelonae which are commonly found in both domestic and hospital water systems.

AIMS

To describe the investigation and control measures following two patient cases of M. chelonae and positive water samples in the study hospital.

METHODS

Water testing was undertaken from outlets, storage tanks and mains supply. Whole-genome sequencing (WGS) was used to compare patient and positive water samples. The subsequent infection control measures implemented are described.

FINDINGS

The WGS results showed two main populations of M. chelonae within the group of sampled isolates. The results showed that the patient strains were unrelated to each other, but that the isolate from one patient was closely related to environmental samples from water outlets, supporting nosocomial acquisition.

CONCLUSIONS

WGS was used to investigate two patient cases of M. chelonae and positive water samples from a hospital water supply. Relevant control measures and the potential for chemical dosing of water systems to enhance proliferation of atypical mycobacteria are discussed.

Erroneous expression of NKG2D on granulocytes detected by phycoerythrin-conjugated clone 149810 antibody

BACKGROUND

The activating Natural killer group 2 member D (NKG2D) receptor is typically expressed on NK cells, CD8 T lymphocytes, γδ T cells and small subsets of CD4 T lymphocytes. During the course of an extensive flow cytometry phenotyping of immune cells in the peripheral blood of patients with glioblastoma multiforme (GBM) we noticed an unexpected expression of NKG2D receptor on granulocytes using the phycoerythrin (PE)-conjugated clone 149810 antibody.

METHODS

Peripheral blood samples from 35 patients with GBM and 22 age-matched healthy control (HC) donors were analyzed using flow cytometry, imaging cytometry and real-time quantitative reverse transcription PCR to validate the observed expression of NKG2D receptor on myeloid cells.

RESULTS

Reactivity with PE-149810 was mostly observed on granulocytes from GBM patients on dexamethasone treatment where it correlated with inferior survival rates. Surprisingly, such NKG2D expression on granulocytes was not observed using the allophycocyanin (APC)-conjugate of the same clone 149810 antibody or an indirect staining procedure with unconjugated clone 149810 antibody. Moreover, the PE-conjugate of a different anti-NKG2D clone (1D11) also did not stain granulocytes. Imaging cytometry indicated cell surface and intracellular localization of PE-149810 but not of PE-1D11 in granulocytes.

CONCLUSION

Our results uncover an erroneous and false positive reactivity of PE-labeled (but not of APC-labeled or unconjugated) anti-NKG2D antibody 149810 on granulocytes from dexamethasone-treated GBM patients and raise a note of caution for studies of NKG2D expression on non-lymphoid cells.

Features of the Energy Spectrum of Cosmic Rays above 2.5×10^{18} eV Using the Pierre Auger Observatory

We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18}  eV based on 215 030 events. New results are presented: at about 1.3×10^{19}  eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19}  eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18}  eV is [5.66±0.03(stat)±1.40(syst)]×10^{53}  erg Mpc^{-3}.

Allogeneic Vγ9Vδ2 T-cell immunotherapy exhibits promising clinical safety and prolongs the survival of patients with late-stage lung or liver cancer

Vγ9Vδ2 T cells are promising candidates for cellular tumor immunotherapy. Due to their HLA-independent mode of action, allogeneic Vγ9Vδ2 T cells can be considered for clinical application. To apply allogeneic Vγ9Vδ2 T cells in adoptive immunotherapy, the methodology used to obtain adequate cell numbers with optimal effector function in vitro needs to be optimized, and clinical safety and efficacy also need to be proven. Therefore, we developed a novel formula to improve the expansion of peripheral γδ T cells from healthy donors. Then, we used a humanized mouse model to validate the therapeutic efficacy of expanded γδ T cells in vivo; furthermore, the expanded γδ T cells were adoptively transferred into late-stage liver and lung cancer patients. We found that the expanded cells possessed significantly improved immune effector functions, including proliferation, differentiation, and cancer cell killing, both in vitro and in the humanized mouse model. Furthermore, a phase I clinical trial in 132 late-stage cancer patients with a total of 414 cell infusions unequivocally validated the clinical safety of allogeneic Vγ9Vδ2 T cells. Among these 132 patients, 8 liver cancer patients and 10 lung cancer patients who received ≥5 cell infusions showed greatly prolonged survival, which preliminarily verified the efficacy of allogeneic Vγ9Vδ2 T-cell therapy. Our clinical studies underscore the safety and efficacy of allogeneic Vγ9Vδ2 T-cell immunotherapy, which will inspire further clinical investigations and eventually benefit cancer patients.

Cancer immunotherapy with γδ T cells: many paths ahead of us

γδ T cells play uniquely important roles in stress surveillance and immunity for infections and carcinogenesis. Human γδ T cells recognize and kill transformed cells independently of human leukocyte antigen (HLA) restriction, which is an essential feature of conventional αβ T cells. Vγ9Vδ2 γδ T cells, which prevail in the peripheral blood of healthy adults, are activated by microbial or endogenous tumor-derived pyrophosphates by a mechanism dependent on butyrophilin molecules. γδ T cells expressing other T cell receptor variable genes, notably Vδ1, are more abundant in mucosal tissue. In addition to the T cell receptor, γδ T cells usually express activating natural killer (NK) receptors, such as NKp30, NKp44, or NKG2D which binds to stress-inducible surface molecules that are absent on healthy cells but are frequently expressed on malignant cells. Therefore, γδ T cells are endowed with at least two independent recognition systems to sense tumor cells and to initiate anticancer effector mechanisms, including cytokine production and cytotoxicity. In view of their HLA-independent potent antitumor activity, there has been increasing interest in translating the unique potential of γδ T cells into innovative cellular cancer immunotherapies. Here, we discuss recent developments to enhance the efficacy of γδ T cell-based immunotherapy. This includes strategies for in vivo activation and tumor-targeting of γδ T cells, the optimization of in vitro expansion protocols, and the development of gene-modified γδ T cells. It is equally important to consider potential synergisms with other therapeutic strategies, notably checkpoint inhibitors, chemotherapy, or the (local) activation of innate immunity.

Potential infection control risks associated with chilled beam technology: experience from a UK hospital

Energy efficiency technologies are now a feature in hospital design, with active chilled beams an example of one in use worldwide. Such innovations have clear benefits but there is a paucity of information with respect to any infection control risks. We describe our experience of chilled beam technology from one of our hospitals where we faced challenges with cleaning and episodes of water ingress including condensation. We highlight the importance of infection control risk assessment in relation to new technologies and the implementation of appropriate risk mitigation.

Toward Healthy Diets from Sustainable Food Systems

This article is based on a session at ASN 2019 entitled "Addressing the Four Domains of Sustainable Food Systems Science (Health, Economics, Society and the Environment): What Will It Take to Harmonize the Evidence to Advance the Field?" A summary of presentations is included. The presentations addressed the 4 principal domains of sustainability defined as nutrition/health, economics, environment, and society and the ways in which they are represented in current research. The session also introduced metrics and measures that are specific to each domain. Participants discussed next steps to move toward consensus and collaboration among scientific communities, especially those of health/nutrition science and environmental science. Food systems may need to be restructured to ensure that the global food supply provides adequate calories and nutrients at an affordable cost. Finally, the session addressed strategies to implement research concepts and move toward policies that encourage consumers to choose healthy diets from sustainable food systems.

Characterization of a new molecule capable of inhibiting several steps of the amyloid cascade in Alzheimer's disease

INTRODUCTION

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder in elderly people. Existent therapies are directed at alleviating some symptoms, but are not effective in altering the course of the disease.

METHODS

Based on our previous study that showed that an Aβ-interacting small peptide protected against the toxic effects of amyloid-beta peptide (Aβ), we carried out an array of in silico, in vitro, and in vivo assays to identify a molecule having neuroprotective properties.

RESULTS

In silico studies showed that the molecule, referred to as M30 (2-Octahydroisoquinolin-2(1H)-ylethanamine), was able to interact with the Aβ peptide. Additionally, in vitro assays showed that M30 blocked Aβ aggregation, association to the plasma membrane, synaptotoxicity, intracellular calcium, and cellular toxicity, while in vivo experiments demonstrated that M30 induced a neuroprotective effect by decreasing the toxicity of Aβ in the dentate gyrus of the hippocampus and improving the alteration in spatial memory in behavior assays.

DISCUSSION

Therefore, we propose that this new small molecule could be a useful candidate for the additional development of a treatment against AD since it appears to block multiple steps in the amyloid cascade. Overall, since there are no drugs that effectively block the progression of AD, this approach represents an innovative strategy.

SIGNIFICANCE

Currently, there is no effective treatment for AD and the expectations to develop an effective therapy are low. Using in silico, in vitro, and in vivo experiments, we identified a new compound that is able to inhibit Aβ-induced neurotoxicity, specifically aggregation, association to neurons, synaptic toxicity, calcium dyshomeostasis and memory impairment induced by Aβ. Because Aβ toxicity is central to AD progression, the inhibition mediated by this new molecule might be useful as a therapeutic tool.

Influence of Indoleamine-2,3-Dioxygenase and Its Metabolite Kynurenine on γδ T Cell Cytotoxicity against Ductal Pancreatic Adenocarcinoma Cells

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is a malignant gastrointestinal disease. The enzyme indoleamine-2,3-dioxgenase (IDO) is often overexpressed in PDAC and its downstream metabolite kynurenine has been reported to inhibit T cell activation and proliferation. Since γδ T cells are of high interest for T cell-based immunotherapy against PDAC, we studied the impact of IDO and kynurenine on γδ T cell cytotoxicity against PDAC cells.

METHODS

IDO expression was determined in PDAC cells by flow cytometry and Western blot analysis. PDAC cells were cocultured with γδ T cells in medium or were stimulated with phosphorylated antigens or bispecific antibody in the presence or absence of IDO inhibitors. Additionally, γδ T cells were treated with recombinant kynurenine. Read-out assays included degranulation, cytotoxicity and cytokine measurement as well as cell cycle analysis.

RESULTS

Since IDO overexpression was variable in PDAC, IDO inhibitors improved γδ T cell cytotoxicity only against some but not all PDAC cells. γδ T cell degranulation and cytotoxicity were significantly decreased after their treatment with recombinant kynurenine.

CONCLUSIONS

Bispecific antibody drastically enhanced γδ T cell cytotoxicity against all PDAC cells, which can be further enhanced by IDO inhibitors against several PDAC cells, suggesting a striking heterogeneity in PDAC escape mechanisms towards γδ T cell-mediated anti-tumor response.

Vitamin C supports conversion of human γδ T cells into FOXP3-expressing regulatory cells by epigenetic regulation

Human γδ T cells are potent cytotoxic effector cells, produce a variety of cytokines, and can acquire regulatory activity. Induction of FOXP3, the key transcription factor of regulatory T cells (Treg), by TGF-β in human Vγ9 Vδ2 T cells has been previously reported. Vitamin C is an antioxidant and acts as multiplier of DNA hydroxymethylation. Here we have investigated the effect of the more stable phospho-modified Vitamin C (pVC) on TGF-β-induced FOXP3 expression and the resulting regulatory activity of highly purified human Vγ9 Vδ2 T cells. pVC significantly increased the TGF-β-induced FOXP3 expression and stability and also increased the suppressive activity of Vγ9 Vδ2 T cells. Importantly, pVC induced hypomethylation of the Treg-specific demethylated region (TSDR) in the FOXP3 gene. Genome-wide methylation analysis by Reduced Representation Bisulfite Sequencing additionally revealed differentially methylated regions in several important genes upon pVC treatment of γδ T cells. While Vitamin C also enhances effector functions of Vγ9 Vδ2 T cells in the absence of TGF-β, our results demonstrate that pVC potently increases the suppressive activity and FOXP3 expression in TGF-β-treated Vγ9 Vδ2 T cells by epigenetic modification of the FOXP3 gene.

Mass and the Dangers of Syncope

Introduction Syncope is defined as a transient, self-limited loss of consciousness with an inability to maintain postural tone that is followed by spontaneous recovery. We revisit situational syncope focusing on one situation, Mass. Methods We interrogated our electronic syncope database for key terms associated with situational syncope. From the most commonly encountered situation, Mass, we interrogated the results of tilt testing performed to identify evidence of orthostatic hypotension. Results There were 110 cases of situational syncope identified with 56.3% (n=62) taking place at mass. All had tilt table testing performed and 15.4% (n=17) had evidence of orthostatic hypotension. Conclusion The multiple sudden changes in position during mass from sitting to kneeling to standing can precipitate an episode of orthostatic hypotension. Consideration should be given as to whether it is safe for older mass goers to be subjected to such significant orthostatic stress.

Influence of nonsynaptic α1 glycine receptors on ethanol consumption and place preference

Here, we used knock-in (KI) mice that have ethanol-insensitive alpha 1 glycine receptors (GlyRs) (KK385/386AA) to examine how alpha 1 GlyRs might affect binge drinking and conditioned place preference. Data show that tonic alpha 1 GlyR-mediated currents were exclusively sensitive to ethanol only in wild-type mice. Behavioral studies showed that the KI mice have a higher intake of ethanol upon first exposure to drinking and greater conditioned place preference to ethanol. This study suggests that nonsynaptic alpha 1-containing GlyRs have a role in motivational and early reinforcing effects of ethanol.