Dark citizen science

Citizen science is often celebrated. We interrogate this position through exploration of socio-technoscientific phenomena that mirror citizen science yet are disaligned with its ideals. We term this 'Dark Citizen Science'. We identify five conceptual dimensions of citizen science - purpose, process, perceptibility, power and public effect. Dark citizen science mirrors traditional citizen science in purpose and process but diverges in perceptibility, power and public effect. We compare two Internet-based categorisation processes, Citizen Science project Galaxy Zoo and Dark Citizen Science project Google's reCAPTCHA. We highlight that the reader has, likely unknowingly, provided unpaid technoscientific labour to Google. We apply insights from our analysis of dark citizen science to traditional citizen science. Linking citizen science as practice and normative democratic ideal ignores how some science-citizen configurations actively pit practice against ideal. Further, failure to fully consider the implications of citizen science for science and society allows exploitative elements of citizen science to evade the sociological gaze.

Implementation Science in Radiation Oncology: Case Study for Liver SBRT

PURPOSE/OBJECTIVE(S)

The translation of research into clinical practice is challenging and implementation science is becoming as important as the trial design and development. Implementation science methodologies have been shown to reduce research-to-practice gap in other clinical settings. This is especially true for the field of Radiation Oncology where modern hypofractionated techniques, like Stereotactic Ablative Body Radiotherapy for Liver are at a high risk of over enthusiastic implementation as well as underutilization. We present the results of a multicomponent implementation methodology utilized to develop our Liver SBRT program as a model to safely translate a complex technology into clinical practice.

MATERIALS/METHODS

After review of literature and market research a setup was created with focus on machine requirements, immobilization devices, motion management techniques and QA techniques. Clinical tools in the form of checklists were developed for patient selection, simulation along with image fusion, target delineation, planning (conformity indices, dose constraint criteria) and treatment delivery. All patients were treated on Truebeam® after Bodyfix® immobilization with plastic wrap. Planning was completed on Eclipse TPS with dose constraints and conformity guidelines defined per the RTOG 1112 and TG 101. Clinical outcomes including clinical and imaging follow-up for tumor control and toxicity were recorded. For this report, all patients treated were reviewed and compared to published data to assess the success of the implementation methodology.

RESULTS

A total of 64 consecutive Patients treated with liver SBRT at Dignity Health Cancer Institute (DHCI) were eligible for the study. 58 patients treated for primary liver malignancies were included in this analysis to assess outcomes including control of disease and toxicity to compare to the published literature. Median follow up for these patients 6.5 months (4-46mnths). Median GTV volume was 38.7cc (0.1cc-2056.1 cc), median PTV volume was 159.35 cc (21.5cc-2673.5cc). Median SBRT prescription dose was 50 Gy/5 fractions (35-50 Gy). Median Liver- GTV was 1595.8 cc(770.7cc-2983.0cc). Following toxicities were noted- Grade 1- 10.3%, Grade 2 - 1.72%, Grade 3- 3.44%. No Grade 4 toxicity was noted. 1 year LC rate was 96.6%. 8.6% showed out of field liver failure and 6.9% developed distant metastasis. These results were compared to the current published literature and are shown to be comparable.

CONCLUSION

Strong and well thought out Implementation methodologies can ensure reproducing results in clinical practice, comparable to the controlled environment of trials. These are crucial in translation of clinical trials utilizing advanced technologies to promote the culture of safety in clinical practice of Radiation Oncology. Regular assessment and tracking of clinical outcomes can be used as Quality markers for directing care and reimbursements for future.

Accuracy of clinical predictions of prognosis at the end-of-life: evidence from routinely collected data in urgent care records

BACKGROUND

The accuracy of prognostication has important implications for patients, families, and health services since it may be linked to clinical decision-making, patient experience and outcomes and resource allocation. Study aim is to evaluate the accuracy of temporal predictions of survival in patients with cancer, dementia, heart, or respiratory disease.

METHODS

Accuracy of clinical prediction was evaluated using retrospective, observational cohort study of 98,187 individuals with a Coordinate My Care record, the Electronic Palliative Care Coordination System serving London, 2010-2020. The survival times of patients were summarised using median and interquartile ranges. Kaplan Meier survival curves were created to describe and compare survival across prognostic categories and disease trajectories. The extent of agreement between estimated and actual prognosis was quantified using linear weighted Kappa statistic.

RESULTS

Overall, 3% were predicted to live "days"; 13% "weeks"; 28% "months"; and 56% "year/years". The agreement between estimated and actual prognosis using linear weighted Kappa statistic was highest for patients with dementia/frailty (0.75) and cancer (0.73). Clinicians' estimates were able to discriminate (log-rank p < 0.001) between groups of patients with differing survival prospects. Across all disease groups, the accuracy of survival estimates was high for patients who were likely to live for fewer than 14 days (74% accuracy) or for more than one year (83% accuracy), but less accurate at predicting survival of "weeks" or "months" (32% accuracy).

CONCLUSION

Clinicians are good at identifying individuals who will die imminently and those who will live for much longer. The accuracy of prognostication for these time frames differs across major disease categories, but remains acceptable even in non-cancer patients, including patients with dementia. Advance Care Planning and timely access to palliative care based on individual patient needs may be beneficial for those where there is significant prognostic uncertainty; those who are neither imminently dying nor expected to live for "years".

Survival in patients with radiological diagnoses of glioblastoma: a retrospective study of 115 patients on a best supportive care pathway

Aims

Glioblastoma multiforme (GBM) is a devastating disease with notoriously poor survival. Studies examining survival in patients given best supportive care (BSC) are few and far between. All patients harbouring brain tumours referred to the Neuro-oncology service at the Queen Elizabeth Hospital in Birmingham are recorded in the Somerset Cancer Registry. We set out to analyse survival times and identify patient and tumour-related factors significantly affecting prognosis.

Method

We identified 126 patients from 2015 to 2019 in our Somerset Cancer Registry with radiological diagnoses of glioblastoma for whom the Neuro-oncology MDT recommended BSC. We performed a retrospective analysis of clinical records and radiological images. 11 patients were excluded (8 due to insufficient imaging data, 2 who underwent subsequent surgery, 1 patient with brain metastases). Survival was measured in completed weeks since the index MDT decision. Associations between survival time and both patient- and tumour-related factors were assessed using Kaplan-Meier curves and log-rank tests. All analyses were performed using IBM SPSS 22 (IBM Corp. Armonk, NY), with p&lt;0.05 deemed to be indicative of statistical significance throughout.

Results

Data were available for N=115 patients (69 males, 46 females), with a mean age of 79 ± 8 years. All patients died within 32 weeks of diagnosis, with a median survival time of 8 weeks. Only 8 patients survived for more than 20 weeks. Survival was significantly shorter in those with a greater number of main cerebral structures affected (p=0.044), with a median of 6 vs. 10 weeks for 3 or more vs. 1 structures affected (hazard ratio: 1.61, 95% CI: 0.99-2.62). Bilateral tumours involving the corpus callosum were also associated with shorter survival (p=0.039). None of the other factors considered were found to be significantly associated with survival, including age (p=0.193), gender (p=0.371), performance status (p=0.300) and tumour size (p=0.331).

Conclusion

With the exception of the number of main cerebral structures affected (frontal, parietal, temporal and occipital lobes, corpus callosum, insula, basal ganglia and brain stem), patient- and tumour-factors traditionally used by the MDT to prognosticate do not correlate with survival time in patients receiving BSC for radiological diagnoses of GBM. With 50% of the cohort dying within 8 weeks it is clear that we must reconsider the timing of referrals to palliative and hospice care. Finally, the fact that some patients survived for more than half a year with no surgical or oncological treatment suggests that the process of selecting patients for BSC vs aggressive treatments needs refinement.

Spinal surgery during the COVID-19 pandemic: the experience in a tertiary referral centre

Background

The COVID-19 pandemic first came to prominence in December 2019, and since then has swept the globe, causing one of the largest public health problems seen. It has had a wide-ranging impact on healthcare provision, with a cessation of elective operating. We aimed to assess the impact of COVID-19 on a tertiary referral centre for spinal surgery in England.

Methods

An 82-day study period from 20^th March 2020 to 10^th June 2020 was used, and all spinal surgical patients were followed up prospectively, comparing patients from the same date range in 2019. We assessed rate of COVID transmission, 30-day mortality rates, complication rates and length of hospital stay in a large tertiary Teaching hospital in England.

Results

Seventy-eight patients were operated on during the COVID-19 pandemic period, with a 30-day mortality rate of 4.2%. Two of these deaths were attributable to COVID-19 (2.56%). The mean length of stay was 10.8 days. Neither the 30-day mortality rate or the length of stay was statistically significant compared to the 2019 control period. Five patients (6.4%) tested positive for COVID-19, all were negative at time of surgical intervention. Our complication rate was 10.3% during the COVID-19 pandemic period.

Conclusions

The number of operative cases performed during the COVID-19 pandemic fell by one-third compared to the same period in 2019. The COVID-19 pandemic did not cause a significant increase in 30-day mortality rate, length of stay, or complication rates. Further studies with larger patient numbers and longer-term outcomes will be needed to fully assess the impact of the COVID-19 pandemic on spinal surgery.

Abstract 6288: A high-throughput in vitro characterization method of CAR T cells using image cytometry

Since the FDA approval of two CAR T cell therapies, Kymriah (Tisagenlecleucel, Novartis) and Yescarta (Axicabtagene ciloleucel, Kite) for CD19+ malignancies, there has been a significant interest for developing new CARs targeting other disease indications. As such, the ability to simultaneously monitor manufacturing criteria and functional characteristics of multiple CAR T cell products would likely be critical to accelerate candidate therapies into clinical trials. Here, we demonstrate that image-based cytometry using the Celigo Image Cytometer (Nexcelom Bioscience LLC) yields high-throughput measurements of CAR T cell proliferation and size throughout the cell-manufacturing process, and captures the kinetics of antigen-specific CAR T cell-mediated killing in vitro. The data acquired and analyzed by the Celigo Image Cytometer were congruent with results from conventional instruments when tested contemporaneously, such as the Multisizer 3 (Beckman Coulter) which monitored the properties of CAR T cell expansion, and a luciferase-based assay which measured the cytotoxic potential of CAR T cells. More importantly, the use of bright field and fluorescent imaging by the Celigo Image Cytometer provided kinetic measurements and rapid data acquisition and analysis which were direct advantages over the conventional technologies described herein. Together, the Celigo Image Cytometer enabled fast, reproducible, and high-throughput assessment of CAR T cell manufacturing criteria and effector function, which could greatly facilitate the identification and evaluation of novel CARs with therapeutic potential.

Citation Format: Leo Li-Ying Chan, Colby Maldini, Andrea Love, Kevin Tosh, Kevin Gayout, Tim Smith, James Riley. A high-throughput in vitro characterization method of CAR T cells using image cytometry [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6288.

Three-dimensional electroconvective vortices in cross flow

This study focuses on the three-dimensional (3D) electrohydrodynamic flow instability between two parallel electrodes driven by unipolar charge injection with and without cross flow. Lattice Boltzmann method with a two-relaxation time model is used to compute flow patterns. In the absence of cross flow, the base-state solution is hydrostatic, and the electric field is one-dimensional. With strong charge injection and high electrical Rayleigh number, the system exhibits electroconvective vortices. Disturbed by perturbation patterns, such as rolling pattern, square pattern, and hexagon pattern, the flow develops corresponding to the most unstable mode. The growth rate and pattern transitions are studied using dynamic mode decomposition of the transient numerical solutions. The interactions between cross flow and electroconvective vortices lead to suppression and disappearance of structures with velocity components in the direction of cross flow, while the other components are not affected. Surprisingly, the transition from a 3D to a 2D flow pattern enhances the convective charge transport, marked by an increase in the electric Nusselt number. Hysteresis in the 3D to 2D transition is characterized by the nondimensional parameter Y, a ratio of the electrical force term to the viscous term in the momentum equation.

Predation by introduced cats Felis catus on Australian frogs: compilation of species records and estimation of numbers killed

Abstract ContextWe recently estimated the numbers of reptiles, birds and mammals killed by cats (Felis catus) in Australia, with these assessments providing further evidence that cats have significant impacts on Australian wildlife. No previous studies have estimated the numbers of frogs killed by cats in Australia and there is limited comparable information from elsewhere in the world. AimsWe sought to (1) estimate the numbers of frogs killed by cats in Australia and (2) compile a list of Australian frog species known to be killed by cats. MethodsFor feral cats, we estimated the number of frogs killed from information on their frequency of occurrence in 53 cat dietary studies (that examined stomach contents), the mean number of frogs in dietary samples that contained frogs, and the numbers of cats in Australia. We collated comparable information for take of frogs by pet cats, but the information base was far sparser. Key resultsFrogs were far more likely to be reported in studies that sampled cat stomachs than cat scats. The mean frequency of occurrence of frogs in cat stomachs was 1.5%. The estimated annual per capita consumption by feral cats in Australia’s natural environments is 44 frogs, and, hence, the annual total take is estimated at 92 million frogs. The estimated annual per capita consumption by pet cats is 0.26 frogs, for a total annual kill of one million frogs by pet cats. Thirty native frog species (13% of the Australian frog fauna) are known to be killed by cats: this tally does not include any of the 51 threatened frog species, but this may simply be because no cat dietary studies have occurred within the small ranges typical of threatened frog species. ConclusionsThe present study indicated that cats in Australia kill nearly 100 million frogs annually, but further research is required to understand the conservation significance of such predation rates. ImplicationsThe present study completed a set of reviews of the impacts of cats on Australian terrestrial vertebrates. Cat predation on Australian frogs is substantial, but is likely to be markedly less than that on Australian reptiles, birds and mammals.

Study of key resonances in the 30P(p,γ)31S reaction in classical novae

Among reactions with strong impact on classical novae model predictions, 30P(p,γ)31S is one of the few remained that are worthy to be measured accurately, because of their rate uncertainty, as like as 18F(p,α)15O and 25Al(pγ)26Si. To reduce the nuclear uncertainties associated to this reaction, we performed an experiment at ALTO facility of Orsay using the 31P(3He,t)31S reaction to populate 31S excited states of astrophysical interest and detect in coincidence the protons coming from the decay of the populated states in order to extract the proton branching ratios. After a presentation of the astrophysical context of this work, the current situation of the 30P(p,γ)31S reaction rate will be discussed. Then the experiment set-up of this work and the analysis of the single events will be presented.

Direct Measurement of the Key E_{c.m.}=456 keV Resonance in the Astrophysical ^{19}Ne(p,γ)^{20}Na Reaction and Its Relevance for Explosive Binary Systems

We have performed a direct measurement of the ^{19}Ne(p,γ)^{20}Na reaction in inverse kinematics using a beam of radioactive ^{19}Ne. The key astrophysical resonance in the ^{19}Ne+p system has been definitely measured for the first time at E_{c.m.}=456_{-2}^{+5}  keV with an associated strength of 17_{-5}^{+7}  meV. The present results are in agreement with resonance strength upper limits set by previous direct measurements, as well as resonance energies inferred from precision (^{3}He, t) charge exchange reactions. However, both the energy and strength of the 456 keV resonance disagree with a recent indirect study of the ^{19}Ne(d, n)^{20}Na reaction. In particular, the new ^{19}Ne(p,γ)^{20}Na reaction rate is found to be factors of ∼8 and ∼5 lower than the most recent evaluation over the temperature range of oxygen-neon novae and astrophysical x-ray bursts, respectively. Nevertheless, we find that the ^{19}Ne(p,γ)^{20}Na reaction is likely to proceed fast enough to significantly reduce the flux of ^{19}F in nova ejecta and does not create a bottleneck in the breakout from the hot CNO cycles into the rp process.

Improving the diagnostic quality and adequacy of shoulder radiographs in a District General Hospital

A high rate of suboptimal shoulder radiographs was identified during a service evaluation exercise in our orthopaedic outpatient clinics. Inadequate radiographs require a return to the radiology department for further imaging, a resultant increased workload, delays in the clinic, increased radiation for patients, and inconvenience and decreased patient satisfaction. Furthermore, if a sub-optimal radiograph is accepted there is concern that diagnoses may be missed. The aim of this project was to decrease the rate of suboptimal radiographs by delivering a teaching package directed towards quality improvement.

Evaluation criteria were set for standard orthopaedic shoulder radiographs (Anterior-posterior, axillary, and Velpeau views). Baseline data collection was performed over three, two-week periods and included all patients attending the shoulder clinic. The percentage of x-rays which were deemed adequate was only 19.4% for anterior-posterior views and 57.9% for axillary views.

A comprehensive educational package was delivered to radiographers. This included a formal PowerPoint based teaching session, hands on training with practice using a skeleton, posters with step-by step instructions on how to obtain an adequate image, and PDF aide memoires suitable for viewing on a smartphone. Two subsequent two-week periods of data collection were performed to evaluate the benefit of this intervention.

Delivery of focussed training and provision of easily accessible aide memoires to facilitate improved quality of radiographs resulted in a significant (p<0.05) reduction in the rate of inadequate images. There was also a significant decreases in the rate of return to the radiology department for repeat imaging.

Randomised crossover trial of telemonitoring in chronic respiratory patients (TeleCRAFT trial)

Objective

To assess the impact of home telemonitoring on health service use and quality of life in patients with severe chronic lung disease.

Design

Randomised crossover trial with 6 months of standard best practice clinical care (control group) and 6 months with the addition of telemonitoring.

Participants

68 patients with chronic lung disease (38 with COPD; 30 with chronic respiratory failure due to other causes), who had a hospital admission for an exacerbation within 6 months of randomisation and either used long-term oxygen therapy or had an arterial oxygen saturation (SpO₂) of <90% on air during the previous admission. Individuals received telemonitoring (second-generation system) via broadband link to a hospital-based care team.

Outcome measures

Primary outcome measure was time to first hospital admission for an acute exacerbation. Secondary outcome measures were hospital admissions, general practitioner (GP) consultations and home visits by nurses, quality of life measured by EuroQol-5D and hospital anxiety and depression (HAD) scale, and self-efficacy score (Stanford).

Results

Median (IQR) number of days to first admission showed no difference between the two groups—77 (114) telemonitoring, 77.5 (61) control (p=0.189). Hospital admission rate at 6 months increased (0.63 telemonitoring vs 0.32 control p=0.026). Home visits increased during telemonitoring; GP consultations were unchanged. Self-efficacy fell, while HAD depression score improved marginally during telemonitoring.

Conclusions

Telemonitoring added to standard care did not alter time to next acute hospital admission, increased hospital admissions and home visits overall, and did not improve quality of life in chronic respiratory patients.

Trial registration number

NCT02180919 (ClinicalTrials.gov).

Can Alcohol Intoxication be Excluded as the Cause of Confusion following Head Injury?

Objective: To assess whether there is a breath alcohol level (BrAC) below which confusion in the head injured patient should not be attributed solely to the acute effects of alcohol Method: Based in the Accident and Emergency Ward in Glasgow Royal Infirmary, a prospective observational study was carried out over a five month period. Patients admitted to the ward were recruited for the study if they had a primary diagnosis of head injury. The outcome measures recorded and analysed were sequential 2 hrly BrAC readings (mg/L) and Glasgow Coma Scale findings (Eye opening, motor and verbal responses). The relationship between these was investigated, which revealed additional relevant factors affecting level of consciousness. Results: The breath alcohol analyser was found to be a useful non-invasive, quick and easy to use tool. The results obtained were consistent with the expected pattern of reducing BrAC levels over a 6 hour period. Within this group of patients, a poor correlation was found between each of the three responses of the Glasgow Coma Scale and BrAC readings. For those patients who remained confused, when their BrAC reading was less than 1 mg/L, other causes of a lowered level of consciousness were identified. Conclusion: Confusion in the head injured patient with a BrAC of less than 1 mg/L, should alert one to the likelihood of causes other than alcohol intoxication.

Routine screening for pain combined with a pain treatment protocol in head and neck cancer: a randomised controlled trial

BACKGROUND

We compared the effectiveness and cost of a pain screening and treatment program, with usual care in head and neck cancer patients with significant pain.

METHODS

Patients were screened for the presence of pain and then randomly assigned to either an intervention group, consisting of a pain treatment protocol and an education program, or to usual care. Primary outcome was change in the Pain Severity Index (PSI) over three months.

RESULTS

We screened 1074 patients of whom 156 were randomized to either intervention or usual care. Mean PSI was reduced over three months in both groups, with no significant difference between the two groups. The Pain Management Index (PMI) at three months, was significantly improved in the intervention group compared with usual care (P<0.001), as was Patient Satisfaction (mean difference in scores was statistically significant: -0.30 [-0.60 to -0.15]). All subjects reported clinically significant levels of anxiety and depression throughout the study. Treatment costs were significantly higher for intervention (mean=£400) compared with usual care (£200), with a low likelihood of being cost-effective.

CONCLUSIONS

There was no difference in the Pain Severity Index between the two groups. However there were significant improvements in the intervention group in patient satisfaction and PMI. The pain screening process itself was effective. Sufficient benefit was demonstrated as a result of the intervention to allow continued development of pain treatment pathways, rather than allowing pain treatment to be left to nonformalised ad hoc arrangements.

Randomized controlled trial of asthma risk with paracetamol use in infancy--a feasibility study

BACKGROUND

There is non-experimental evidence that paracetamol (acetaminophen) use may increase the risk of developing asthma. However, numerous methodological issues need to be resolved before undertaking a randomized controlled trial to investigate this hypothesis.

OBJECTIVE

To establish the feasibility of a randomized controlled trial of liberal paracetamol as usually given by parents/guardians vs. a comparator (restricted paracetamol in accordance with WHO guidelines, ibuprofen or placebo), and childhood asthma risk.

METHODS

Questionnaires were completed by parents/guardians of infants admitted to Wellington Hospital with bronchiolitis to assess views about comparator treatments. Subsequently, infants of parents/guardians who provided informed consent were randomized to restricted or liberal paracetamol use for 3 months with paracetamol use recorded.

RESULTS

Of 120 eligible participants, 72 (60%) parents/guardians completed the questionnaire. Ibuprofen, restricted paracetamol and placebo were acceptable to 42 (58%), 29 (40%) and 9 (12%) parents/guardians, respectively. 36 (30%) infants were randomized to restricted or liberal paracetamol. Paracetamol use was greater for the liberal vs. restricted group for reported [Hodges-Lehmann estimator of difference 0.94 mg/kg/day (95% CI 0.2-3.52), P = 0.02] and measured use [Hodges-Lehmann estimator of difference 2.11 mg/kg/day (95% CI 0.9-4.18), P = 0.004]. The median reported and measured use of paracetamol was 2.0-fold and 3.5-fold greater in the liberal vs. restricted group.

CONCLUSIONS AND CLINICAL RELEVANCE

Although separation in paracetamol dosing is likely to be achieved with a liberal vs. restricted paracetamol regime, ibuprofen is the preferred comparator treatment in the proposed RCT of paracetamol use and risk of asthma in childhood.

High-affinity TCRs confer antigen sensitivity in HIV gag-specific effector CD8 T cells (VAC7P.991)

Virus infected cells are eliminated by CTLs when TCR recognizes viral Ag on MHC. Previously, we demonstrated that HIV-1-GAG specific high-affinity (ha) TCR enhanced CD8 T cell killing of HIV-1-infected cells. To elucidate why haTCR expressing T cells were better at controlling HIV-1 replication, we asked whether WT or haTCRs expressing primary human T cells had a distinct cytokine profile when stimulated with monomeric pMHC attached to magnetic beads. In this minimalistic T cell activation system, we observed robust IFNγ, TNFα, IL-2 and MIP1β induction in the presence or absence of CD28 stimulation. Interestingly, αCD3 coated beads do not induce cytokine expression. Previously, we and others demonstrated that αCD3 stimulation failed to induce AKT activation, which has a prominent role in cytokine production. Here, TCR signaling alone activates AKT. Next, we addressed whether T cells expressing haTCRs were able to respond to less Ag, and thereby control HIV-1 replication better by destroying HIV-1 infected cells before they could effectively spread the virus. By mixing various ratios of cognate pMHC with non-cognate pMHC on magnetic beads, we show that CD8 T cells, and not CD4 T cells, expressing haTCRs are able to induce Ag specific activation of phospho-ERK1/2 and -AKT with a ~10 fold increased sensitivity when compared with WT TCR expressing T cells. Thus, implicating CD8 as playing an important role in regulating how a T cell perceives differences in TCR affinity.

Identification of an acetylation-dependant Ku70/FLIP complex that regulates FLIP expression and HDAC inhibitor-induced apoptosis

FLIP is a potential anti-cancer therapeutic target that inhibits apoptosis by blocking caspase 8 activation by death receptors. We report a novel interaction between FLIP and the DNA repair protein Ku70 that regulates FLIP protein stability by inhibiting its polyubiquitination. Furthermore, we found that the histone deacetylase (HDAC) inhibitor Vorinostat (SAHA) enhances the acetylation of Ku70, thereby disrupting the FLIP/Ku70 complex and triggering FLIP polyubiquitination and degradation by the proteasome. Using in vitro and in vivo colorectal cancer models, we further demonstrated that SAHA-induced apoptosis is dependant on FLIP downregulation and caspase 8 activation. In addition, an HDAC6-specific inhibitor Tubacin recapitulated the effects of SAHA, suggesting that HDAC6 is a key regulator of Ku70 acetylation and FLIP protein stability. Thus, HDAC inhibitors with anti-HDAC6 activity act as efficient post-transcriptional suppressors of FLIP expression and may, therefore, effectively act as 'FLIP inhibitors'.

Genetic variation in opioid receptor genes and sensitivity to experimental pain in male and female healthy volunteers

Background/aims

Pain is a common problem which significantly impacts on quality of life. Clinical pain is complicated to study due to numerous confounding variables. Normal volunteer models use standardised painful stimuli with resulting reduced phenotype variability. Current studies suggest an association between genetic variability and pain sensitivity.

Methods

Data from 50 healthy volunteers in three studies of multi-modal, multi-tissue experimental pain stimulation were included. Skin heat, muscle cuff pressure and visceral pressure were analysed. Genetic variants in the genes coding for the mu, delta and kappa opioid receptors (OPRM, OPRD and OPRK) were studied using multivariate regression modelling to investigate association with pain sensitivity.

Results

Reproducibility of baseline data for skin heat, muscle cuff pressure and visceral pressure between studies was confirmed (Cronbach’s α > 0.8). Gender differences in pain sensitivity were seen. Females were more sensitive to skin heat and muscle pressure (P =0.006 and 0.02 respectively). Genetic associations were also found. OPRK was associated with both skin heat pain (P =0.009) and muscle cuff pain (P =0.003). Visceral pressure pain was not associated with either gender or genotype.

Conclusion

Genetic variations in the kappa opioid receptor appear to mediate different pain modalities. Gender remains an independent predictor of pain sensitivity.

Alternate function of Foxp3 in human CD4+ T cells (179.2)

Foxp3 is the master regulator of T-reg phenotype and function. Unlike murine T cells, human T cells express two versions of Foxp3 of which the smaller form is missing exon 2 (Δ2). Previously we showed that Foxp3Δ2 fails to up-regulate the Pim 2 kinase and others have reported that members of the ROR family bind to exon 2 of Foxp3. Nonetheless, it is not clear if these isoforms differentially affect regulatory and nonregulatory T cell function. This study demonstrate that transduction of Foxp3 and Foxp3Δ2 into primary human CD4+CD45RA+CD25- naïve T cells induced suppressive activity that was identical to natural T-regs. However, in CD4+CD45RA-CD25- memory T cells, the full-length Foxp3 construct was unable to introduce a suppressive phenotype, whereas Foxp3Δ2 retained its ability to promote suppressive activity. Furthermore, memory cells transduced with Foxp3 abrogated the suppressive functions of naïve cells transduced with Foxp3 but not with Foxp3Δ2.Cytokine profiling indicated a 3 fold increase in the IL-2+IFN-γ+ cells within the memory cells transduced with Foxp3. Altogether these observations reveal an isoform dependent alternate function of Foxp3 in the CD4+ memory T cell compartment. These studies support the use of naïve T cells for strategies that transduce effector T cells with Foxp3 expressing vectors as a means to rapidly generate T-regs for use in adoptive T cell therapy against autoimmune diseases.

Outcomes of surgical management of bowel obstruction in relapsed epithelial ovarian cancer (EOC)

OBJECTIVE

To describe the outcomes of surgical management of bowel obstruction in relapsed epithelial ovarian cancer (EOC) so as to define the criteria for patient selection for palliative surgery.

METHODS

90 women with relapsed EOC underwent palliative surgery for bowel obstruction between 1992 and 2008.

RESULTS

Median age at time of surgery for bowel obstruction was 57 years (range, 26 to 85 years). All patients had received at least one line of platinum-based chemotherapy. Median time from diagnosis of primary disease to documented bowel obstruction requiring surgery was 19.5 months (range, 29 days-14 years). Median interval from date of completed course of chemotherapy preceding surgery for bowel obstruction was 3.8 months (range, 5 days-14 years). Ascites was present in 38/90(42%). 49/90(54%) underwent emergency surgery for bowel obstruction. The operative mortality and morbidity rates were 18% and 27%, respectively. Successful palliation, defined as adequate oral intake at least 60 days postoperative, was achieved in 59/90(66%). Only the absence of ascites was identified as a predictor for successful palliation (p=0.049). The median overall survival (OS) was 90.5 days (range, <1 day-6 years). Optimal debulking, treatment-free interval (TFI) and elective versus emergency surgery did not predict survival or successful palliation from surgery for bowel obstruction (p>0.05).

CONCLUSION

Surgery for bowel obstruction in relapsed EOC is associated with a high morbidity and mortality rate especially in emergency cases when compared to other gynaecological oncological procedures. Palliation can be achieved in almost two thirds of cases, is equally likely in elective and emergency cases but is less likely in those with ascites.

Determining the orientation of a chiral substrate using full-hemisphere angle-resolved photoelectron spectroscopy

Chiral interfaces and substrates are of increasing importance in the field of enantioselective chemistry. To fully understand the enantiospecific interactions between chiral adsorbate molecules and the chiral substrate, it is vital that the chiral orientation of the substrate is known. In this Letter we demonstrate that full-hemisphere angle-resolved photoemission permits straightforward identification of the orientation of a chiral surface. The technique can be applied to any solid state system for which photoemission measurements are possible.

Naturally occurring MHC class I restricted TCRs effectively redirect human T regulatory cells to suppress high affinity, polyfunctional CD8 T cell responses (52.8)

Because most autoimmune diseases exist in the periphery, we investigated whether MHC class I restricted TCRs could be used to re-direct expanded human Tregs in order to better target engineered Tregs to the site of the aberrant immune response. By taking advantage of a series of HLA-A2 restricted TCRs that recognize the same peptide-MHC class I (pMHC) with varying affinities, we observed augmenting TCR affinity had no effect on the ability of Tregs to function. In fact, MHC class I restricted TCRs that had limited activity in CD4+ T effector cells (Teff) were fully able to suppress the expansion of highly functional CD8 T cells expressing a high affinity TCR. These studies demonstrate that Tregs expressing naturally occurring, introduced MHC class I restricted TCRs have potent suppressive activity and further highlight the fundamental differences that exist between effector and regulatory T cells.

Human CD8β isoforms with distinct cytoplasmic tails differ in modulating T cell response and regulated cell surface expression (109.31)

The CD8αβ coreceptor influences CD8 T cell recognition and responses in anti-tumor and -viral immunity. The ancestor to the human and chimpanzee CD8β gene acquired two additional exons absent in the mouse that lead to the expression of multiple isoforms (M1-M4) as a result of alternative splicing. In humans these isoforms differ in their cytoplasmic tails and in their expression pattern. The M-1 isoform is predominant in naïve T cells whereas M-4 is predominant in effector memory T cells. To study functional differences we are co-transducing CD8α, each CD8β isoform, and MHCI restricted NY-ESO-1 specific TCR into human CD4+ T cells and measuring cytokine production after activation. We have found differences in induction of cytokine producing cells such as the MIP-1β chemokine with different isoforms. The M-4 isoform cytoplasmic tail has unique sorting motifs that regulate its cell surface expression and it is modified by phosphorylation after activation. The cytoplasmic tail of M-4 could associate with ubiquitinated substrates in 293T cells and was itself mono-ubiquitinated. The M-4 isoform has unique properties that likely favored its selection in effector memory T cells.

KLF2 expression modulates susceptibility to HIV-1 infection (154.25)

Here, we show that the transcription factor KLF2 is a host factor with a role in modulating susceptibility to HIV-1 infection. We observed a strong correlation between expression of KFL2 and CCR5. Transformed CD4 T cell lines lack CCR5 as well as KLF2 expression. Forced expression of KFL2 in transformed cell lines induced CCR5 expression and rendered them susceptible to R5 HIV-1 infection, providing insight into why most transformed lines fail to support CCR5 dependent HIV-1 replication. In primary human CD4 T cells, KFL2 expression is rapidly downregulated after T cell activation and is undetectable after anti-CD3/28 costimulation, whereas trace amounts remain after PHA + IL-2 stimulation. This residual amount of KLF2 present after T cell activation correlates well with CCR5 expression and susceptibility to R5 infection. Primary human CD4 T engineered to constitutively express KLF2 retained CCR5 expression and susceptibility to R5 infection after CD3/28 costimulation. These studies implicate KLF2 expression levels present after T cell activation as the determinant of whether a T cell is susceptible to R5 HIV-1 infection. Thus, KLF2 is a host factor that could affect an individual’s susceptibility to HIV-1 infection and the rate by which one progresses to AIDS.

Viral infection duration mediates locus specific de novo DNA methylation in antigen-specific CD8 T cells (154.41)

Progressive loss of antiviral functions in antigen-specific CD8 T cell during chronic infection is caused by continuous upregulation and signaling by immunoinhibitory receptors including Programmed Death 1(PD-1). Using human and murine model systems of acute and chronic viral infections, we found that differentiation of naïve CD8 T cells into effector cells during acute infection was accompanied by a transient loss of DNA methylation of the PD-1 locus. Viral clearance and the subsequent effector to memory differentiation resulted in memory-specific DNA remethylation of the PD-1 locus. Conversely, chronic infection induced complete and sustained DNA demethylation of the PD-1 regulatory region in exhausted CD8 T cells. Surprisingly, reduction of virus levels and PD-1 expression in chronically infected animals did not result in remethylation and coincided with decreased expression of a specific de novo methyltransferase (Dnmt3a) isoform. The unmethylated PD-1 locus allowed for rapid PD-1 re-expression, potentially prematurely terminating antiviral functions. These studies provide a foundation for efforts towards reprogramming of PD-1 expression to rejuvenate exhausted T cells.

Safety profile of rofecoxib as used in general practice in England: results of a prescription-event monitoring study

Focal points