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AimsThe response to high frequency stimulation (HFS) is used to locate putative sites of ganglionated plexuses (GPs), which are implicated in triggering atrial fibrillation (AF). To identify topological and immunohistochemical characteristics of presumed GP sites functionally identified by HFS.Methods and resultsSixty-three atrial sites were tested with HFS in four Langendorff-perfused porcine hearts. A 3.5 mm tip quadripolar ablation catheter was used to stimulate and deliver HFS to the left and right atrial epicardium, within the local atrial refractory period. Tissue samples from sites triggering atrial ectopy/AF (ET) sites and non-ET sites were stained with choline acetyltransferase (ChAT) and tyrosine hydroxylase (TH), for quantification of parasympathetic and sympathetic nerves, respectively. The average cross-sectional area (CSA) of nerves was also calculated. Histomorphometry of six ET sites (9.5%) identified by HFS evoking at least a single atrial ectopic was compared with non-ET sites. All ET sites contained ChAT-immunoreactive (ChAT-IR) and/or TH-immunoreactive nerves (TH-IR). Nerve density was greater in ET sites compared to non-ET sites (nerves/cm2: 162.3 ± 110.9 vs. 69.65 ± 72.48; P = 0.047). Overall, TH-IR nerves had a larger CSA than ChAT-IR nerves (µm2: 11 196 ± 35 141 vs. 2070 ± 5841; P < 0.0001), but in ET sites, TH-IR nerves were smaller than in non-ET sites (µm2: 6021 ± 14 586 vs. 25 254 ± 61 499; P < 0.001).ConclusionsET sites identified by HFS contained a higher density of smaller nerves than non-ET sites. The majority of these nerves were within the atrial myocardium. This has important clinical implications for devising an effective therapeutic strategy for targeting autonomic triggers of AF.

Aims Conflicting data exist supporting differing mechanisms for sustaining ventricular fibrillation (VF), ranging from disorganised multiple-wavelet activation to organised rotational activities (RAs). Abnormal gap junction (GJ) coupling and fibrosis are important in initiation and maintenance of VF. We investigated whether differing ventricular fibrosis patterns and the degree of GJ coupling affected the underlying VF mechanism. Methods and Results Optical mapping of 65 Langendorff-perfused rat hearts was performed to study VF mechanisms in control hearts with acute GJ modulation, and separately in three differing chronic ventricular fibrosis models; compact (CF), diffuse (DiF) and patchy (PF). VF dynamics were quantified with phase mapping and frequency dominance index (FDI) analysis, a power ratio of the highest amplitude dominant frequency in the cardiac frequency spectrum. Enhanced GJ coupling with rotigaptide (n = 10) progressively organised fibrillation in a concentration-dependent manner; increasing FDI (0nM: 0.53±0.04, 80nM: 0.78±0.03, p

Arterial thoracic outlet syndrome (ATOS) is rare. We present our 30-year experience with the management of ATOS at a high-volume referral center.A retrospective review of all patients who had undergone primary operative treatment for ATOS from 1988 to 2018 was performed. ATOS was defined as subclavian artery pathology caused by extrinsic compression from a bony abnormality within the thoracic outlet.A total of 41 patients (45 limbs) underwent surgery for ATOS at a median age of 46 years (interquartile range [IQR], 34-58 years). Chronic symptoms (6 weeks) were present in 31 limbs (69%). Of the 45 limbs, 13 (29%) presented with acute limb ischemia (ALI), requiring urgent brachial artery thromboembolectomy (BAT) in 9 and catheter-directed thrombolysis and thrombectomy (CDT) in 4. All patients underwent thoracic outlet decompression. 31 limbs (69%) required subclavian artery reconstruction. No perioperative deaths and only one major adverse limb event occurred. Patients with ALI underwent staged thoracic outlet decompression after initial BAT or CDT at a median of 23 days (IQR, 11-140 days). Of the 13 limbs with an initial presentation of ALI, 8 (62%) had recurrent thromboembolic events before thoracic outlet decompression subsequently requiring 10 additional BATs and 1 CDT. The cumulative probability of recurrent embolization at 14, 30, and 90 days was 8.33% (95% confidence interval [CI], 1.28%-54.42%), 16.67% (95% CI, 4.70%-59.06%), and 33.33% (95% CI, 14.98-74.20%), respectively. The median follow-up for 32 patients (35 limbs) was 13 months (IQR, 5-36 months). Subclavian artery/graft primary and secondary patency was 87% and 90%, respectively, at 5 years by Kaplan-Meier analysis. Of the 35 limbs, 5 (14%) had chronic upper extremity pain and 5 (14%) had persistent weakness. Preoperative forearm or hand pain and brachial artery occlusion were associated with chronic pain (P = .04 and P = .03) and weakness (P = .03 and P = .02). Of the 13 limbs that presented with ALI, 11 had a median follow-up after thoracic outlet decompression of 6 months (IQR, 5-14 months), including 9 (82%) with oral anticoagulation therapy. Anticoagulation therapy had no effect on subclavian artery patency (P = 1.0) or the presence of chronic symptoms (P = .93).The presentation of ATOS is diverse, and the diagnosis can be delayed. Preoperative upper extremity pain and brachial artery occlusion in the setting of ALI were associated with chronic pain and weakness after thoracic outlet decompression. Delayed thoracic outlet decompression was associated with an increased risk of recurrent thromboembolic events for patients who presented with ALI. An early and accurate diagnosis of ATOS is necessary to reduce morbidity and optimize outcomes.

Aneurysms of the superior mesenteric artery (SMA) and its branches are rare and account for only 6% to 15% of all visceral artery aneurysms. In the present report, we have described our 30-year experience with the management of aneurysms of the SMA and its branches at a high-volume referral center.A retrospective review of all patients with a diagnosis of an aneurysm of the SMA or one of its branches from 1988 to 2018 was performed. Pseudoaneurysms and mycotic aneurysms were excluded. The clinical presentation, etiology, aneurysm shape and size, treatment modalities, and outcomes were analyzed. The growth rate of the aneurysms was estimated using linear regression.A total of 131 patients with 144 aneurysms were reviewed. The patients were primarily men (64%), with a median age of 60 years. Of the 144 aneurysms, 57 were fusiform, 30 were saccular, and 57 were dissection-associated aneurysms. Of the 131 patients, 41 had had an isolated SMA branch aneurysm. Degenerative aneurysms were the most common etiology (66%). A total of 35 patients (27%) were symptomatic at presentation. Of the 144 aneurysms, 111 had multiple computed tomography angiograms available, with a median follow-up of 43.6 months (interquartile range, 10.6-87.2 months). Only 18 aneurysms (16%) had had an estimated growth rate of ≥1.0 mm/y. The initial aneurysm size was significantly associated with the growth rate for the fusiform aneurysms (odds ratio [OR], 1.13; 95% confidence interval [CI], 1.0-1.3]; P = .02) but not for the saccular (OR, 0.91; 95% CI, 0.76-1.1; P = 1.1) or dissection-associated (OR, 1.2; 95% CI, 0.91-1.5; P = .20) aneurysms. Acute abdominal pain (OR, 5.9; 95% CI, 1.6-22; P = .01) and chronic abdominal pain (OR, 3.7; 95% CI, 1.1-13; P = .04) were associated with aneurysm growth. Only two patients had a ruptured aneurysm, both of whom presented with rupture with no prior imaging studies. These two patients had a diagnosis of fibromuscular dysplasia and systemic lupus erythematosus, respectively. Of the 131 patients, 46 (34%) had undergone operative repair, including 36 open revascularizations and 8 endovascular procedures. The average aneurysm size for these 46 patients was 24.0 ± 8.6 mm. One patient died perioperatively, and nine patients experienced perioperative complications (25%). Of the 144 aneurysms, 91 were 20 mm, with an average size of 13.4 ± 3.1 mm. These 91 aneurysms had been followed up for a median of 120.8 months (interquartile range, 30.5-232.2 months), with no ruptures within this cohort during the follow-up period.The present study represents one of the largest series on aneurysms of the SMA and its branches. Our results showed that aneurysms of the SMA are relatively stable. Patients with symptomatic and fusiform aneurysms had a greater risk of growth. Aneurysms 20 mm with a degenerative etiology can be safely monitored without treatment.

During viral pandemics, filtering facepiece (FFP) masks together with eye protection form the essential components of personal protective equipment (PPE) for healthcare workers. There remain concerns regarding insufficient global supply and imperfect protection offered by currently available PPE strategies. A range of full-face snorkel masks were adapted to accept high grade medical respiratory filters using bespoke-designed 3D-printed connectors. We compared the protection offered by the snorkel to that of standard PPE using a placebo-controlled respirator filtering test as well as a fluorescent droplet deposition experiment. Out of the 56 subjects tested, 42 (75%) passed filtering testing with the snorkel mask compared to 31 (55%) with a FFP3 respirator mask (p = 0.003). Amongst the 43 subjects who were not excluded following a placebo control, 85% passed filtering testing with the snorkel versus to 68% with a FFP3 mask (p = 0.008). Following front and lateral spray of fluorescence liquid particles, the snorkel mask also provided superior protection against droplet deposition within the subject's face, when compared to a standard PPE combination of FFP3 masks and eye protection (3.19x108 versus 6.81x108 fluorescence units, p0.001). The 3D printable adaptors are available for free download online at https://www.ImperialHackspace.com/COVID-19-Snorkel-Respirator-Project/.Full-face snorkel masks adapted as particulate respirators performed better than a standard PPE combination of FFP3 mask and eye protection against aerosol inhalation and droplet deposition. This adaptation is therefore a promising PPE solution for healthcare workers during highly contagious viral outbreaks.

Engineered heart tissue (EHT) strategies, by combining cells within a hydrogel matrix, may be a novel therapy for heart failure. EHTs restore cardiac function in rodent injury models, but more data are needed in clinically relevant settings. Accordingly, an upscaled EHT patch (2.5 cm × 1.5 cm × 1.5 mm) consisting of up to 20 million human induced pluripotent stem cell-derived cardiomyocytes (hPSC-CMs) embedded in a fibrin-based hydrogel was developed. A rabbit myocardial infarction model was then established to test for feasibility and efficacy. Our data showed that hPSC-CMs in EHTs became more aligned over 28 days and had improved contraction kinetics and faster calcium transients. Blinded echocardiographic analysis revealed a significant improvement in function in infarcted hearts that received EHTs, along with reduction in infarct scar size by 35%. Vascularization from the host to the patch was observed at week 1 and stable to week 4, but electrical coupling between patch and host heart was not observed. In vivo telemetry recordings and ex vivo arrhythmia provocation protocols showed that the patch was not pro-arrhythmic. In summary, EHTs improved function and reduced scar size without causing arrhythmia, which may be due to the lack of electrical coupling between patch and host heart.

Introduction During viral pandemics, filtering facepiece (FFP) masks together with eye protection form the essential components of personal protective equipment (PPE) for healthcare workers. There remain concerns regarding insufficient global supply and imperfect protection offered by currently available PPE strategies. A range of full-face snorkel masks were adapted to accept high grade medical respiratory filters using bespoke-designed 3D-printed connectors. We compared the protection offered by the snorkel to that of standard PPE using a placebo-controlled respirator filtering test as well as a fluorescent droplet deposition experiment. Out of the 56 subjects tested, 42 (75%) passed filtering testing with the snorkel mask compared to 31 (55%) with a FFP3 respirator mask (p = 0.003). Amongst the 43 subjects who were not excluded following a placebo control, 85% passed filtering testing with the snorkel versus to 68% with a FFP3 mask (p = 0.008). Following front and lateral spray of fluorescence liquid particles, the snorkel mask also provided superior protection against droplet deposition within the subject’s face, when compared to a standard PPE combination of FFP3 masks and eye protection (3.19x108 versus 6.81x108 fluorescence units, phttps://www.ImperialHackspace.com/COVID-19-Snorkel-Respirator-Project/. Conclusion Full-face snorkel masks adapted as particulate respirators performed better than a standard PPE combination of FFP3 mask and eye protection against aerosol inhalation and droplet deposition. This adaptation is therefore a promising PPE solution for healthcare workers during highly contagious viral outbreaks.

Background: Emerging data suggest that the combination of MEK inhibitors and immunotherapeutic agents may result in improved efficacy in melanoma. We evaluated whether combining MEK inhibition and immune checkpoint inhibition was more efficacious than immune checkpoint inhibition alone in patients with previously untreated BRAFV600 wild-type advanced melanoma. Patients and methods: IMspire170 was an international, randomized, open-label, phase III study. Patients were randomized 1 : 1 to receive cobimetinib (60 mg, days 1-21) plus anti-programmed death-ligand 1 atezolizumab (840 mg every 2 weeks) in 28-day cycles or anti-programmed death-1 pembrolizumab (200 mg every 3 weeks) alone until loss of clinical benefit, unacceptable toxicity, or consent withdrawal. The primary outcome was progression-free survival (PFS), assessed by an independent review committee in the intention-to-treat population. Results: Between 11 December 2017, and 29 January 2019, 446 patients were randomized to receive cobimetinib plus atezolizumab (n = 222) or pembrolizumab (n = 224). Median follow-up was 7.1 months [interquartile range (IQR) 4.8-9.9] for cobimetinib plus atezolizumab and 7.2 months (IQR 4.9-10.1) for pembrolizumab. Median PFS was 5.5 months [95% confidence interval (CI) 3.8-7.2] with cobimetinib plus atezolizumab versus 5.7 months (95% CI 3.7-9.6) with pembrolizumab [stratified hazard ratio 1.15 (95% CI 0.88-1.50); P = 0.30]. Hazard ratios for PFS were consistent across prespecified subgroups. In exploratory biomarker analyses, higher tumor mutational burden was associated with improved clinical outcomes in both treatment arms. The most common grade 3-5 adverse events (AEs) were increased blood creatine phosphokinase (10.0% with cobimetinib plus atezolizumab versus 0.9% with pembrolizumab), diarrhea (7.7% versus 1.9%), rash (6.8% versus 0.9%), hypertension (6.4% versus 3.7%), and dermatitis acneiform (5.0% versus 0). Serious AEs occurred in 44.1% of patients with cobimetinib plus atezolizumab and 20.8% with pembrolizumab. Conclusion: Cobimetinib plus atezolizumab did not improve PFS compared with pembrolizumab monotherapy in patients with BRAFV600 wild-type advanced melanoma. © 2020 European Society for Medical Oncology

Acute myocardial ischaemia and reperfusion (I–R) are major causes of ventricular arrhythmias in patients with a history of coronary artery disease. Ursodeoxycholic acid (UDCA) has previously been shown to be antiarrhythmic in fetal hearts. This study was performed to investigate if UDCA protects against ischaemia-induced and reperfusion-induced arrhythmias in the adult myocardium, and compares the effect of acute (perfusion only) versus prolonged (2 weeks pre-treatment plus perfusion) UDCA administration. Langendorff-perfused adult Sprague–Dawley rat hearts were subjected to acute regional ischaemia by ligation of the left anterior descending artery (10 min), followed by reperfusion (2 min), and arrhythmia incidence quantified. Prolonged UDCA administration reduced the incidence of acute ischaemia-induced arrhythmias (p = 0.028), with a reduction in number of ventricular ectopic beats during the ischaemic phase compared with acute treatment (10 ± 3 vs 58 ± 15, p = 0.036). No antiarrhythmic effect was observed in the acute UDCA administration group. Neither acute nor prolonged UDCA treatment altered the incidence of reperfusion arrhythmias. The antiarrhythmic effect of UDCA may be partially mediated by an increase in cardiac wavelength, due to the attenuation of conduction velocity slowing (p = 0.03), and the preservation of Connexin43 phosphorylation during acute ischaemia (p = 0.0027). The potential antiarrhythmic effects of prolonged UDCA administration merit further investigation.

We describe a human and large animal Langendorff experimental apparatus for live electrophysiological studies and measure the electrophysiological changes due to gap junction uncoupling in human and porcine hearts. The resultant ex vivo intact human and porcine model can bridge the translational gap between smaller simple laboratory models and clinical research. In particular, electrophysiological models would benefit from the greater myocardial mass of a large heart due to its effects on far-field signal, electrode contact issues and motion artefacts, consequently more closely mimicking the clinical setting. Porcine (n = 9) and human (n = 4) donor hearts were perfused on a custom-designed Langendorff apparatus. Epicardial electrograms were collected at 16 sites across the left atrium and left ventricle. A total of 1 mM of carbenoxolone was administered at 5 ml/min to induce cellular uncoupling, and then recordings were repeated at the same sites. Changes in electrogram characteristics were analysed. We demonstrate the viability of a controlled ex vivo model of intact porcine and human hearts for electrophysiology with pharmacological modulation. Carbenoxolone reduces cellular coupling and changes contact electrogram features. The time from stimulus artefact to (-dV/dt)max increased between baseline and carbenoxolone (47.9 ± 4.1–67.2 ± 2.7 ms) indicating conduction slowing. The features with the largest percentage change between baseline and carbenoxolone were fractionation + 185.3%, endpoint amplitude − 106.9%, S-endpoint gradient + 54.9%, S point − 39.4%, RS ratio + 38.6% and (-dV/dt)max − 20.9%. The physiological relevance of this methodological tool is that it provides a model to further investigate pharmacologically induced pro-arrhythmic substrates.

Background The underlying mechanism of ventricular fibrillation (VF) remains unclear. There are both experimental and clinical data to support the existence of rotational drivers (RDs), though other opposing studies suggest that VF is the result of disorganized myocardial activation. Abnormal electrical coupling between cardiomyocytes through gap junctions (GJ) has been considered an important factor in the genesis and maintenance of VF and pre-treatment with GJ couplers, rotigaptide (RTG), has been shown to reduce VF inducibility. Purpose We hypothesized that the degree of GJ coupling determines the underlying mechanism of VF, and that changes in GJ coupling can shift or modify the predominant mechanism of fibrillation along the spectrum between disorganised activity and organised drivers. We proposed that increased organisation of VF is critical to its termination. Methods Thirty Sprague-Dawley rat hearts were explanted, perfused ex-vivo and acute VF was induced with burst pacing and 30μM pinacidil. Optical mapping of transmembrane potential was performed at baseline and the effects of GJ coupling on VF dynamics were studied in an acute VF model by perfusing with increasing concentrations of a GJ uncoupler; carbenoxolone (0–50μM, CBX, n=10) or a GJ coupling-enhancer; RTG (0–80nM, n=10). A chronic diffuse fibrosis model (n=10) was generated with 4 weeks of in-vivo angiotensin infusion (500nm/kg/min). Fibrillation dynamics were quantified using phase analysis, phase singularity (PS) tracking and our novel method of global fibrillation organisation quantification, frequency dominance index (FDI), which is a power ratio of highest amplitude dominant frequency in the frequency spectrum. Results RTG increased average rotations per RD (Baseline: 2.86±0.10 vs 80nM: 5.66±0.43, p5 rotations. FDI increased with RTG (0.53±0.04 vs 0.78±0.3, p Conclusion The degree of GJ coupling is a key determinant of the underlying mechanism of VF. RTG organised fibrillation and stabilised RDs in a concentration-dependent manner whilst CBX disorganised VF. Enhancing GJ coupling with RTG in diseased hearts with fibrosis can terminate VF and may be a potential therapeutic target in acute VF. Acknowledgement/Funding BHF Programme Grant PG/16/17/32069

Background Ventricular fibrosis is known to play a critical role in initiation and maintenance of ventricular fibrillation (VF). Post myocardial infarction the quantity of fibrosis negatively correlates with survival. There is a lack of data on how the quantity and degree of fibrosis influences the mechanisms of VF itself. VF mechanisms remain debated, there are data to support both critical areas sustaining rotational drivers (RDs) and the contrary hypothesis of disorganized myocardial activation driving VF. Purpose We hypothesized that the underlying mechanism of VF is influenced by the spatial distribution and quantity of ventricular fibrosis. Methods Thirty-five Sprague-Dawley rats underwent permanent left anterior descending (LAD) ligation (n=11), 20mins LAD territory ischaemia-reperfusion (n=13) or in-vivo angiotensin infusion (500ng/kg/min, n=11) to generate compact (CF), patchy (PF) and diffuse fibrosis (DF) models respectively. After a 4-week maturation period, the hearts were explanted, Langendorff perfused and VF induced with burst pacing and 30μM pinacidil. Fibrillation dynamics were quantified using phase analysis, phase singularity (PS) tracking and our novel method of global fibrillation organisation quantification, frequency dominance index (FDI), which is a power ratio of highest amplitude dominant frequency in the frequency spectrum. Results Ventricular fibrosis for each group was characterized and quantified (CF: 22.3±3.2%, PF: 18.4±4.2%, DF: 5.8±1.3%, p=0.046). VF was driven predominantly by disorganised activity in CF, PSs were detected 26±7% of time comparative to 51.2±4% in DF and 69.5±8% in PF group (p=0.001). PF stabilised RDs, average maximum rotations for a single RD in PF were 31.6±7.1 comparative to 12.5±1.7 in DF and 6.4±1.1 in CF, p Conclusion VF mechanisms occur along a spectrum between organised activity sustained by discrete drivers and disorganised myocardial activation. The underlying VF mechanism can differ significantly dependent on the quantity and pattern of fibrosis. Patchy fibrosis stabilises RDs with localization to discrete areas and sustains an organised form of VF comparative to CF where VF is largely disorganised. Characterising the degree and pattern of fibrosis in patient groups vulnerable to VF might be beneficial in identifying patients with suitable targets for ablation. Acknowledgement/Funding BHF Programme Grant PG/16/17/32069

Background Mechanisms that maintain ventricular fibrillation (VF) remain debated. There are data supporting both critical areas sustaining rotational drivers (RDs) and the contrary hypothesis of disorganised myocardial activation driving VF. Abnormal electrical coupling between cardiomyocytes through gap junctions (GJ) and ventricular fibrosis are major factors in disease related remodelling, and have been implicated in initiation and maintenance of VF. In this study we hypothesised that the mechanism of VF is directly altered by fibrosis and GJ coupling, and that modulating these factors shifts or changes the predominant mechanism of fibrillation along the spectrum between disorganised activity and organised drivers. Methods VF optical mapping was performed in fifty-five perfused rat hearts with differing degrees and patterns of chronic ventricular fibrosis [compact (CF, n=11), patchy (PF, n=13) and diffuse (DF, n=11)], and acute GJ coupling modulation with rotigaptide (RTG, GJ coupling enhancer, 0–80nM, n=10) or carbenoxolone (CBX, GJ uncoupler, 0–50μM, n=10). Fibrillation dynamics were quantified using phase analysis, RD tracking and our novel method of global fibrillation organisation quantification, frequency dominance index (FDI), which is defined as the power ratio of highest amplitude dominant frequency in the frequency spectrum. Results In the fibrosis group, VF was driven predominantly by disorganised activity in CF, RDs were detected 26±7% of time comparative to 51.2±4% in DF and 69.5±8% in PF group (p=0.001). PF stabilised RDs, average maximum rotations for a single RD in PF were 31.6±7.1 comparative to 12.5±1.7 in DF and 6.4±1.1 in CF, p Conclusion VF mechanisms occur along a spectrum between organised activity with discrete drivers and disorganised myocardial activation. The degree of GJ coupling and ventricular fibrosis are key determinants of the underlying mechanism of VF. Enhanced GJ coupling and patchy fibrosis organised fibrillation and stabilised RDs, whilst GJ uncoupling and compact fibrosis disorganised VF. This study presents a unifying explanation for the numerous mechanisms reported for sustaining fibrillation. Characterising the degree and pattern of fibrosis in patient groups vulnerable to VF might be beneficial in identifying patients with targetable substrate, and GJ modulation might be a potential therapeutic target. Conflict of interest Nil

Summary Chimeric antigen receptor anti-CD19 (CAR19)-T cell immunotherapy-induced clinical remissions in CD19+ B cell lymphomas are often short lived. We tested whether CAR19-engineering of the CD1d-restricted invariant natural killer T (iNKT) cells would result in enhanced anti-lymphoma activity. CAR19-iNKT cells co-operatively activated by CD1d- and CAR19-CD19-dependent interactions are more effective than CAR19-T cells against CD1d-expressing lymphomas in vitro and in vivo. The swifter in vivo anti-lymphoma activity of CAR19-iNKT cells and their enhanced ability to eradicate brain lymphomas underpinned an improved tumor-free and overall survival. CD1D transcriptional de-repression by all-trans retinoic acid results in further enhanced cytotoxicity of CAR19-iNKT cells against CD19+ chronic lymphocytic leukemia cells. Thus, iNKT cells are a highly efficient platform for CAR-based immunotherapy of lymphomas and possibly other CD1d-expressing cancers., Graphical Abstract, Highlights • Bespoke protocol for CAR19-iNKT cell transduction and clinical scale expansion • Higher CAR19-iNKT than CAR19-T cell expandability and killing of CD19+CD1d+ targets • CAR19-iNKT cell reactivity potentiation by αGalCer and ATRA • Prolonged survival and brain lymphoma eradication of CAR19-iNKT cell-treated mice, Rotolo et al. show that anti-CD19 chimeric antigen receptor (CAR19)-engineered CD1d-restricted invariant NKT cells (iNKT) are more effective than CAR19-T cells against CD1d-expressing lymphomas, including those in the brain. De-repression of CD1d expression further enhances the anti-tumor efficacy of CAR19-iNKT.

We report that subunits of human nuclear proteasomes carry a previously unrecognised, constitutive posttranslational modification. Subunits with this modification are not visualised by SDS-PAGE, which is used in almost all denaturing protein gel electrophoresis. In contrast, CTAB-PAGE readily visualises such modified subunits. Thus, under most experimental conditions, with identical samples, SDS-PAGE yielded gel electrophoresis patterns for subunits of nuclear proteasomes which were misleading and strikingly different from those obtained with CTAB-PAGE. Initial analysis indicates a novel modification of a high negative charge with some similarity to polyADP-ribose, possibly explaining compatibility with (positively-charged) CTAB-PAGE but not (negatively-charged) SDS-PAGE and providing a mechanism for how nuclear proteasomes may interact with chromatin, DNA and other nuclear components.

Objectives: International guidelines support the use of the Oncotype DX derived Recurrence Score (RS) to provide additional prognostic and predictive information in early breast cancer but experience in the UK is limited. In our prospective study we evaluate this test for the NHS and its impact on costs (subject of a separate abstract) and treatment recommendations by UK oncologists. Methods: 150 tests were made available to consecutive patients with ER+, pN0, pN1itc or pN1mic early breast cancer who had no contraindication to adjuvant chemotherapy (CT) and who would accept CT + hormone therapy (HT) if recommended. CT recommendations of oncologists based on Adjuvant! Online figures were recorded at an initial consultation. Eligible patients were consented to Oncotype DX testing and review arranged once the result was available. After a second consultation a final decision on adjuvant therapy was recorded. Results: Analysis is based on 142 patients. (150 tests performed, 3 failed to give a result, 3 repeated tests giving a result on the second block, one bilateral and one test stopped because the patient withdrew from the study). Initial treatment recommendations changed in 38 (26.8%) cases. Of the patients initially recommended CT + HT (total 57 patients), 26 (45.6%) patients were spared chemotherapy after review with the RS. Of the 85 patients initially recommended HT only 12 (14.1%) were changed to HT + CT. Further analysis shows that Grade, estrogen receptor status by immunohistochemistry (ER by IHC) and progesterone receptor by immunohistochemistry (PR by IHC) are correlated to RS but in our cohort age, size and node status were not. (Spearman rank correlation for grade is 0.05, 95%, Cl 0.36 to 0.61; for ER by IHC is −0.36, Cl −0.49 to −0.20; and for PR by IHC is −0.49, 95%, Cl −0.60 to −0.35). Apart from HER2 positive patients who are already recognized to return a high RS, further analysis of our series shows no clear combination of currently available prognostic factors that would predict RS and therefore reliably avoid testing of any subset of patients. Conclusion: The results of our study suggest that Oncotype DX is applicable and feasible to perform in UK patients with a reduction in the use of adjuvant chemotherapy consistent with findings of reported studies. RS added prognostic information beyond information provided by Adjuvant! Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-14-26.

Dust is produced in tokamaks by the interaction between the plasma and the plasma facing components. Dust has not yet been of a major concern in existing tokamaks mainly because the quantity is small and these devices are not nuclear facilities. However, in ITER and in future reactors, it will represent operational and potential safety issues. From a safety point of view, in order to control the potential dust hazard, the current ITER strategy is based on a defense in depth approach designed to provide reliable confinement systems, to avoid failures, and to measure and minimise the dust inventory. In addition, R&D is put in place for optimisation of the proposed methods, such as improvement of measurement, dust cleaning and the reduction of dust production. The aim of this paper is to present the approach for the control of the dust inventory, relying on the monitoring of envelope values and the development of removal techniques already developed in the existing tokamaks or plasma dedicated devices or which will need further research and development in order to be integrated in ITER.

Nonhomologous end joining (NHEJ) is a critical DNA double-strand break (DSB) repair pathway required to maintain genome stability. Many prokaryotes possess a minimalist NHEJ apparatus required to repair DSBs during stationary phase, composed of two conserved core proteins, Ku and ligase D (LigD). The crystal structure of Mycobacterium tuberculosis polymerase domain of LigD mediating the synapsis of two noncomplementary DNA ends revealed a variety of interactions, including microhomology base pairing, mismatched and flipped-out bases, and 3′ termini forming hairpin-like ends. Biochemical and biophysical studies confirmed that polymerase-induced end synapsis also occurs in solution. We propose that this DNA synaptic structure reflects an intermediate bridging stage of the NHEJ process, before end processing and ligation, with both the polymerase and the DNA sequence playing pivotal roles in determining the sequential order of synapsis and remodeling before end joining.

A tight early fold, the Ballybofey anticline, trends south-eastwards across central Donegal. South-west of its axial trace the Dalradian strata are inverted so that the rocks high in the Series occur at the lowest structural level, next to, and facing downwards, the supposedly Moinian psammites in the core of the Lough Derg antiform. Rapid facies changes occur in the Dalradian rocks across the Caledonian strike.

Within the Dalradian Series of Donegal, the Creeslough, Maas and Fintown successions, which have hitherto been regarded as stratigraphically distinct, are correlated. A standard terminology for this sequence is proposed and a detailed correlation is made with the Ballachulish Succession, which thus forms all the country around the Donegal Granites, northwest of the faults and thrusts which separate it from the Islay Succession.

Ku-dependent nonhomologous end joining (NHEJ) is a double-strand break repair process conserved in all branches of cellular life but has not previously been implicated in the DNA metabolic processes of viruses. We identified Ku homologs in Corndog and Omega, two related mycobacteriophages of Mycobacterium smegmatis. These proteins formed homodimers and bound DNA ends in a manner identical to other Ku's and stimulated joining of ends by the host NHEJ DNA ligase (LigD). Omega and Corndog are unusual in having short 4 base cos ends that would not be expected to self-anneal and would therefore require NHEJ during phage genome circularization. Consistently, M. smegmatis LigD null strains are entirely and selectively unable to support infection by Corndog or Omega, with concomitant failure of genome circularization. These results establish a new paradigm for sequestration of the host cell NHEJ process by bacteriophage and provide a framework for understanding similar transactions in eukaryotic viral infections.

Measurements from an inner wall mounted scanning Langmuir probe and modelling of Dα emission show a sharp fall-off of plasma density in the inboard private flux region. Dα emission is modelled using a one-dimensional space, two-dimensional velocity kinetic neutral code in order to track the changes in the density profile while the magnetic topology is changed from single to double null. A sharp density decay is observed to track with the location of the secondary separatrix. The data presented are consistent with a lower level of cross-field transport on field lines in the private flux region restricted to the high field side when compared to cross-field transport on field lines in the low field side scrape-off layer.

Research on the Alcator C-Mod tokamak [1] is focused on high particle- and power-density plasma regimes to understand particle and energy transport in the core, the dynamics of the H-mode pedestal, and scrape-off layer and divertor physics. The auxiliary heating is provided exclusively by RF waves, and both the physics and technology of RF heating and current drive are studied. The momentum which is manifested in strong toroidal rotation, in the absence of direct momentum input, has been shown to be transported in from the edge of the plasma following the L–H transition, with timescale comparable to that for energy transport. In discharges which develop internal transport barriers, the rotation slows first inside the barrier region, and then subsequently outside of the barrier foot. Heat pulse propagation studies using sawteeth indicate a very narrow region of strongly reduced energy transport, located near r/a = 0.5. Addition of on-axis ICRF heating arrests the buildup of density and impurities, leading to quasi-steady conditions. The quasi-coherent mode associated with enhanced D-Alpha (EDA) H-mode appears to be due to a resistive ballooning instability. As the pedestal pressure gradient and temperature are increased in EDA H-mode, small ELMs appear; detailed modelling indicates that these are due to intermediate n peeling–ballooning modes. Phase contrast imaging has been used to directly detect density fluctuations driven by ICRF waves in the core of the plasma, and mode conversion to an intermediate wavelength ion cyclotron wave has been observed for the first time. The bursty turbulent density fluctuations, observed to drive rapid cross-field particle transport in the edge plasma, appear to play a key role in the dynamics of the density limit. Preparations for quasi-steady-state advanced tokamak studies with lower hybrid current drive are well underway, and time dependent modelling indicates that regimes with high bootstrap fraction can be produced.

The intermittent turbulent transport in the scrape-off-layer (SOL) of Alcator C-Mod [I.H. Hutchinson, R. Boivin, P.T. Bonoli et al., Nucl. Fusion 41, 1391 (2001)] is studied experimentally by imaging with a very high density of spatial measurements. The two-dimensional structure and dynamics of emission from a localized gas puff are observed, and intermittent features (also sometimes called “filaments” or “blobs”) are typically seen. The characteristics of the spatial structure of the turbulence and their relationship to the time-averaged SOL profiles are discussed and compared with those measured on the National Spherical Torus Experiment [M. Ono, S. M. Kaye, Y.-K. M. Pong et al., Nucl. Fusion 40, 557 (2000)]. The experimental observations are compared also with three-dimensional nonlinear numerical simulations of edge turbulence. Radial profiles of the poloidal wave number spectra and the poloidal scale length from the simulations are in reasonable agreement with those obtained from the experimental ima...

In this paper, recent progress in plasma edge modelling is presented, using the SOLPS B2–Eirene Scrape-Off Layer Plasma Simulation code. The code capabilities have been extended so that is it now possible to investigate reliably regimes dominated by strong neutral sources in the plasma edge. Two main improvements are reported. First, a fluid plasma treatment including drift and currents effects has been coupled to a Monte-Carlo treatment for the neutrals. Concurrently, a grid adaptation algorithm compatible with the coupling is demonstrated. We present simulations taking advantage of these new tools, and discuss their impact on the results. 2003 Elsevier Science B.V. All rights reserved.

The EIRENE Monte-Carlo neutral code is used to calculate neutral pressures throughout the divertor region of the Alcator C-Mod tokamak. A semi-empirical onion-skin method (OSM) is used to calculate the hydrogenic background plasma for a moderate density discharge, 〈 n e 〉=1.5×10 20 m −3 , with a partially detached inner target and an attached outer target. The model parameters are adjusted until there is agreement with the Langmuir probe and spectroscopic data for the divertor region. The measured divertor pressure is 30 mTorr, and for C-Mod divertor dimensions this implies the transition flow regime between free molecular and viscous neutral transport. Therefore, a non-linear BGK-model Boltzmann collision term is included in EIRENE to allow for interactions between neutral particles. For the standard model parameters, the calculated divertor pressure is 7 mTorr. The model parameters are adjusted to reduce the discrepancy, and the plausibility of each variation is discussed.

Cytochrome cbb3 oxidase is a member of the haem-copper oxidase superfamily. It is characterized by its high oxygen affinity, while retaining the ability to pump protons. These attributes are central to its proposed role in bacterial microaerobic metabolism. Recent spectroscopic characterization of both the cytochrome cbb3 oxidase complex from Pseudomonas stutzeri and the dihaem ccoP subunit expressed separately in Escherichia coli has revealed the presence of a low-spin His/His co-ordinated c-type cytochrome. The low midpoint reduction potential of this haem (Em < + 100 mV), together with its unexpected ability to bind CO in the reduced state at the expense of the distal histidine ligand, raises questions about the role of the ccoP subunit in the delivery of electrons to the active site.