A Cell-Penetrating Scorpion Toxin Enables Mode-Specific Modulation of TRPA1 and Pain.

TRPA1 is a chemosensory ion channel that functions as a sentinel for structurally diverse electrophilic irritants. Channel activation occurs through an unusual mechanism involving covalent modification of cysteine residues clustered within an amino-terminal cytoplasmic domain. Here, we describe a peptidergic scorpion toxin (WaTx) that activates TRPA1 by penetrating the plasma membrane to access the same intracellular site modified by reactive electrophiles. WaTx stabilizes TRPA1 in a biophysically distinct active state characterized by prolonged channel openings and low Ca2+ permeability. Consequently, WaTx elicits acute pain and pain hypersensitivity but fails to trigger efferent release of neuropeptides and neurogenic inflammation typically produced by noxious electrophiles. These findings provide a striking example of convergent evolution whereby chemically disparate animal- and plant-derived irritants target the same key allosteric regulatory site to differentially modulate channel activity. WaTx is a unique pharmacological probe for dissecting TRPA1 function and its contribution to acute and persistent pain.

Systems-level effects of allosteric perturbations to a model molecular switch.

Molecular switch proteins whose cycling between states is controlled by opposing regulators1,2 are central to biological signal transduction. As switch proteins function within highly connected interaction networks3, the fundamental question arises of how functional specificity is achieved when different processes share common regulators. Here we show that functional specificity of the small GTPase switch protein Gsp1 in Saccharomyces cerevisiae (the homologue of the human protein RAN)4 is linked to differential sensitivity of biological processes to different kinetics of the Gsp1 (RAN) switch cycle. We make 55 targeted point mutations to individual protein interaction interfaces of Gsp1 (RAN) and show through quantitative genetic5 and physical interaction mapping that Gsp1 (RAN) interface perturbations have widespread cellular consequences. Contrary to expectation, the cellular effects of the interface mutations group by their biophysical effects on kinetic parameters of the GTPase switch cycle and not by the targeted interfaces. Instead, we show that interface mutations allosterically tune the GTPase cycle kinetics. These results suggest a model in which protein partner binding, or post-translational modifications at distal sites, could act as allosteric regulators of GTPase switching. Similar mechanisms may underlie regulation by other GTPases, and other biological switches. Furthermore, our integrative platform to determine the quantitative consequences of molecular perturbations may help to explain the effects of disease mutations that target central molecular switches.

Ab Initio and Kinetic Modeling of ß-d-Xylopyranose under Fast Pyrolysis Conditions.

Lignocellulosic biomass is an abundant renewable resource that can be upgraded to chemical and fuel products through a range of thermal conversion processes. Fast pyrolysis is a promising technology that uses high temperatures and fast heating rates to convert lignocellulose into bio-oils in high yields in the absence of oxygen. Hemicellulose is one of the three major components of lignocellulosic biomass and is a highly branched heteropolymer structure made of pentose, hexose sugars, and sugar acids. In this study, ß-d-xylopyranose is proposed as a model structural motif for the essential chemical structure of hemicellulose. The gas-phase pyrolytic reactivity of ß-d-xylopyranose is thoroughly investigated using computational strategies rooted in quantum chemistry. In particular, its thermal degradation potential energy surfaces are computed employing Minnesota global hybrid functional M06-2X in conjunction with the 6-311++G(d,p) Pople basis set. Electronic energies are further refined by performing DLPNO-CCSD(T)-F12 single-point calculations on top of M06-2X geometries using the cc-pVTZ-F12 basis set. Conformational analysis for minima and transition states is performed with state-of-the-art semiempirical quantum chemical methods coupled with metadynamics simulations. Key thermodynamic quantities (free energies, barrier heights, enthalpies of formation, and heat capacities) are computed. Rate coefficients for the initial steps of thermal decomposition are computed by means of reaction rate theory. For the first time, a detailed elementary reaction kinetic model for ß-d-xylopyranose is developed by utilizing the thermodynamic and kinetic information acquired from the aforementioned calculations. This model specifically targets the initial stages of ß-d-xylopyranose pyrolysis in the high-pressure limit, aiming to gain a deeper understanding of its reaction kinetics. This approach establishes a systematic strategy for exploring reactive pathways, evaluating competing parallel reactions, and selectively accepting or discarding pathways based on the analysis. The findings suggest that acyclic d-xylose plays a significant role as an intermediary in the production of key pyrolytic compounds during the pyrolysis of xylose. These compounds include furfural, anhydro-d-xylopyranose, glycolaldehyde, and dihydrofuran-3(2H)-one.

Paradoxical activation of transcription factor SREBP1c and de novo lipogenesis by hepatocyte-selective ATP-citrate lyase depletion in obese mice.

Hepatic steatosis associated with high-fat diet, obesity, and type 2 diabetes is thought to be the major driver of severe liver inflammation, fibrosis, and cirrhosis. Cytosolic acetyl CoA (AcCoA), a central metabolite and substrate for de novo lipogenesis (DNL), is produced from citrate by ATP-citrate lyase (ACLY) and from acetate through AcCoA synthase short chain family member 2 (ACSS2). However, the relative contributions of these two enzymes to hepatic AcCoA pools and DNL rates in response to high-fat feeding are unknown. We report here that hepatocyte-selective depletion of either ACSS2 or ACLY caused similar 50% decreases in liver AcCoA levels in obese mice, showing that both pathways contribute to the generation of this DNL substrate. Unexpectedly however, the hepatocyte ACLY depletion in obese mice paradoxically increased total DNL flux measured by D2O incorporation into palmitate, whereas in contrast, ACSS2 depletion had no effect. The increase in liver DNL upon ACLY depletion was associated with increased expression of nuclear sterol regulatory element-binding protein 1c and of its target DNL enzymes. This upregulated DNL enzyme expression explains the increased rate of palmitate synthesis in ACLY-depleted livers. Furthermore, this increased flux through DNL may also contribute to the observed depletion of AcCoA levels because of its increased conversion to malonyl CoA and palmitate. Together, these data indicate that in fat diet-fed obese mice, hepatic DNL is not limited by its immediate substrates AcCoA or malonyl CoA but rather by activities of DNL enzymes.

Metabolic tumour and nodal response to neoadjuvant chemotherapy on FDG PET-CT as a predictor of pathological response and survival in patients with oesophageal adenocarcinoma.

OBJECTIVES: 2-deoxy-2[18F]Fluoro-D-glucose (FDG) PET-CT has an emerging role in assessing response to neoadjuvant therapy in oesophageal cancer. This study evaluated FDG PET-CT in predicting pathological tumour response (pTR), pathological nodal response (pNR) and survival. METHODS: Cohort study of 75 patients with oesophageal or oesophago-gastric junction (GOJ) adenocarcinoma treated with neoadjuvant chemotherapy then surgery at Guy's and St Thomas' NHS Foundation Trust, London (2017-2020). Standardised uptake value (SUV) metrics on pre- and post-treatment FDG PET-CT in the primary tumour (mTR) and loco-regional lymph nodes (mNR) were derived. Optimum SUVmax thresholds for predicting pathological response were identified using receiver operating characteristic analysis. Predictive accuracy was compared to PERCIST (30% SUVmax reduction) and MUNICON (35%) criteria. Survival was assessed using Cox regression. RESULTS: Optimum tumour SUVmax decrease for predicting pTR was 51.2%. A 50% cut-off predicted pTR with 73.5% sensitivity, 69.2% specificity and greater accuracy than PERCIST or MUNICON (area under the curve [AUC] 0.714, PERCIST 0.631, MUNICON 0.659). Using a 30% SUVmax threshold, mNR predicted pNR with high sensitivity but low specificity (AUC 0.749, sensitivity 92.6%, specificity 57.1%, p = 0.010). pTR, mTR, pNR and mNR were independent predictive factors for survival (pTR hazard ratio [HR] 0.10 95% confidence interval [CI] 0.03-0.34; mTR HR 0.17 95% CI 0.06-0.48; pNR HR 0.17 95% CI 0.06-0.54; mNR HR 0.13 95% CI 0.02-0.66). CONCLUSIONS: Metabolic tumour and nodal response predicted pTR and pNR, respectively, in patients with oesophageal or GOJ adenocarcinoma. However, currently utilised response criteria may not be optimal. pTR, mTR, pNR and mNR were independent predictors of survival. KEY POINTS: • FDG PET-CT has an emerging role in evaluating response to neoadjuvant therapy in patients with oesophageal cancer. • Prospective cohort study demonstrated that metabolic response in the primary tumour and lymph nodes was predictive of pathological response in a cohort of patients with adenocarcinoma of the oesophagus or oesophago-gastric junction treated with neoadjuvant chemotherapy followed by surgical resection. • Patients who demonstrated a response to neoadjuvant chemotherapy in the primary tumour or lymph nodes on FDG PET-CT demonstrated better survival and reduced rates of tumour recurrence.

Seeing the Woods for the Trees? Applying Diagnostic Criteria for Dementia with Lewy Bodies to Patients Presenting with Posterior Cortical Atrophy.

Posterior cortical atrophy (PCA) is a clinico-radiological syndrome characterised by progressive decline in visual processing and other posterior cognitive functions, relatively preserved memory and language in the early stages, and atrophy of posterior brain regions. Often considered a "visual variant" of Alzheimer's disease, a number of other pathological substrates are recognised. Dementia with Lewy Bodies is the second most common neurodegenerative dementia and there is increasing recognition of presentations with little or no parkinsonism, highlighting significant under-recognition of this condition. To complicate matters, some patients with PCA exhibit additional features consistent with other neurodegenerative conditions. We present a series of three such patients presenting with features satisfying the recent consensus criteria for "PCA-Plus (DLB)". We review the current classification of PCA and highlight the importance of deep clinico-radiological phenotyping in neurodegenerative disease to guide targeted interventions and establish future trial-ready cohorts.

An RNAi therapeutic targeting hepatic DGAT2 in a genetically obese mouse model of nonalcoholic steatohepatitis.

Nonalcoholic steatohepatitis (NASH) is a severe liver disorder characterized by triglyceride accumulation, severe inflammation, and fibrosis. With the recent increase in prevalence, NASH is now the leading cause of liver transplant, with no approved therapeutics available. Although the exact molecular mechanism of NASH progression is not well understood, a widely held hypothesis is that fat accumulation is the primary driver of the disease. Therefore, diacylglycerol O-acyltransferase 2 (DGAT2), a key enzyme in triglyceride synthesis, has been explored as a NASH target. RNAi-based therapeutics is revolutionizing the treatment of liver diseases, with recent chemical advances supporting long-term gene silencing with single subcutaneous administration. Here, we identified a hyper-functional, fully chemically stabilized GalNAc-conjugated small interfering RNA (siRNA) targeting DGAT2 (Dgat2-1473) that, upon injection, elicits up to 3 months of DGAT2 silencing (>80%-90%, p < 0.0001) in wild-type and NSG-PiZ "humanized" mice. Using an obesity-driven mouse model of NASH (ob/ob-GAN), Dgat2-1473 administration prevents and reverses triglyceride accumulation (>85%, p < 0.0001) without increased accumulation of diglycerides, resulting in significant improvement of the fatty liver phenotype. However, surprisingly, the reduction in liver fat did not translate into a similar impact on inflammation and fibrosis. Thus, while Dgat2-1473 is a practical, long-lasting silencing agent for potential therapeutic attenuation of liver steatosis, combinatorial targeting of a second pathway may be necessary for therapeutic efficacy against NASH.

Sensitivity of the predicted acoustic pressure field to the wind and temperature profiles in a conventionally neutral boundary layer.

Simulations are widely used to predict noise emissions from traffic, railroad, aircraft, and wind farms and for sound field control. The latter employs multiple sources interacting and it requires accurate phase information. Acoustic models require precise characterization of the medium properties. The logarithmic profile is one of the most commonly used forms to model the wind speed. However, this profile is accurate only in neutral conditions, i.e., when there is not heat flux at the surface. The conventionally neutral boundary layer (CNBL) is the most frequently occurring neutral regime. In this case, the logarithmic profile underestimates the wind speed. This paper analyses the effect that this modelling error has on the sound field close to the ground, for near-ground sources. The first section introduces an approximation of the wind and temperature profiles in such a regime. Afterwards, the sound fields corresponding to the logarithmic profile, a representative CNBL profile, and three more test cases are simulated using the Crank-Nicholson parabolic equation; these are compared employing different metrics. The difference in wind speed introduces a phase error that increases with distance. Moreover, wind speed underestimations also lead to underpredictions of the energy refracted downward.

The Cost of Living with Inherited Ataxia in Ireland.

Inherited ataxias are a heterogenous group of neurodegenerative disorders characterised by progressive impairment of balance and coordination, typically leading to permanent and progressive disability. Diagnosis and management of these disorders incurs a range of direct and indirect financial costs. The aim of this study was to collect individual ataxia-related healthcare resources in a large cohort of individuals with different subtypes of inherited ataxia and calculate the associated cost of illness in the Republic of Ireland. One hundred twenty-nine respondents completed a cross-sectional study on healthcare resource utilisation for progressive ataxia in Ireland. Costs were calculated using a prevalence-based approach and bottom-up methodology. The COI for inherited ataxia in 2016 was €59,993 per person per year. Results were similar between participants with Friedreich's ataxia (FRDA, n = 56), non-FRDA (n = 18) and those with undetermined ataxia (n = 55). Indirect costs, based on productivity losses by participants or caregivers, accounted for 52% of the cost of illness. Inherited ataxia is associated with significant health and social care costs. Further funding for inherited ataxia to ease the financial burden on patients, caregivers and healthcare system and improve standards of care compliance is warranted.

Patient perspectives on key symptoms and preferences for follow-up after upper gastro-intestinal cancer surgery.

PURPOSE: Long-lasting symptoms and reductions in quality of life are common after oesophago-gastric surgery. Post-operative follow-up has traditionally focussed on tumour recurrence and survival, but there is a growing need to also identify and treat functional sequelae to improve patients' recovery. METHODS: An electronic survey was circulated via a British national charity for patients undergoing oesophago-gastric surgery and their families. Patients were asked about post-operative symptoms they deemed important to their quality of life, as well as satisfaction and preferences for post-operative follow-up. Differences between satisfied and dissatisfied patients with reference to follow-up were assessed. RESULTS: Among 362 respondents with a median follow-up of 58 months since surgery (range 3-412), 36 different symptoms were reported as being important to recovery and quality of life after surgery, with a median of 13 symptoms per patient. Most (84%) respondents indicated satisfaction with follow-up. Satisfied patients were more likely to have received longer follow-up (5-year or longer follow-up 60% among satisfied patients vs 27% among unsatisfied, p < 0.001). These were also less likely to have seen a dietitian as part of routine follow-up (37% vs 58%, p = 0.005). CONCLUSION: This patient survey highlights preferences regarding follow-up after oesophago-gastrectomy. Longer follow-up and dietician involvement improved patient satisfaction. Patients reported being concerned by a large number of gastrointestinal and non-gastrointestinal symptoms, highlighting the need for multidisciplinary input and a consensus on how to manage the poly-symptomatic patient.

Transition from esophagectomy to endoscopic therapy for early esophageal cancer.

BACKGROUND: To assess the outcomes of patients with early esophageal cancer and high-grade dysplasia comparing esophagectomy, the historical treatment of choice, to endoscopic eradication therapy (EET). METHODS: Retrospective cohort study of consecutive patients with early esophageal cancer/high-grade dysplasia, treated between 2000 and 2018 at a tertiary center. Primary outcomes were all-cause and disease-specific mortality assessed by multivariable Cox regression and a propensity score matching sub analysis, providing hazard ratios (HR) with 95% confidence intervals (CI) adjusted for age, tumor grade (G1/2 vs. G3), tumor stage, and lymphovascular invasion. Secondary outcomes included complications, hospital stay, and overall costs. RESULTS: Among 269 patients, 133 underwent esophagectomy and 136 received EET. Adjusted survival analysis showed no difference between groups regarding all-cause mortality (HR 1.85, 95% CI 0.73, 4.72) and disease-specific mortality (HR 1.10, 95% CI 0.26, 4.65). In-hospital and 30-day mortality was 0% in both groups. The surgical group had a significantly higher rate of complications (Clavien-Dindo ≥3 26.3% vs. endoscopic therapy 0.74%), longer in-patient stay (median 14 vs. 0 days endoscopic therapy) and higher hospital costs(£16 360 vs. £8786 per patient). CONCLUSION: This series of patients treated during a transition period from surgery to EET, demonstrates a primary endoscopic approach does not compromise oncological outcomes with the benefit of fewer complications, shorter hospital stays, and lower costs compared to surgery. It should be available as the gold standard treatment for patients with early esophageal cancer. Those with adverse prognostic features may still benefit from esophagectomy.

Exercise prehabilitation during neoadjuvant chemotherapy may enhance tumour regression in oesophageal cancer: results from a prospective non-randomised trial.

BACKGROUND: There is increasing evidence for the use of exercise in cancer patients and data supporting enhanced tumour volume reduction following chemotherapy in animal models. To date, there is no reported histopathological evidence of a similar oncological benefit in oesophageal cancer. METHODS: A prospective non-randomised trial compared a structured prehabilitation exercise intervention during neoadjuvant chemotherapy and surgery versus conventional best-practice for oesophageal cancer patients. Biochemical and body composition analyses were performed at multiple time points. Outcome measures included radiological and pathological markers of disease regression. Logistic regression calculated ORs with 95% CI for the likelihood of pathological response adjusting for chemotherapy regimen and chemotherapy delivery. RESULTS: Comparison of the Intervention (n=21) and Control (n=19) groups indicated the Intervention group had higher rates of tumour regression (Mandard TRG 1-3 Intervention n=15/20 (75%) vs Control n=7/19 (36.8%) p=0.025) including adjusted analyses (OR 6.57; 95% CI 1.52 to 28.30). Combined tumour and node downstaging (Intervention n=9 (42.9%) vs Control n=3 (15.8%) p=0.089) and Fat Free Mass index were also improved (Intervention 17.8 vs 18.7 kg/m2; Control 16.3 vs 14.7 kg/m2, p=0.026). Differences in markers of immunity (CD-3 and CD-8) and inflammation (IL-6, VEGF, INF-y, TNFa, MCP-1 and EGF) were observed. CONCLUSION: The results suggest improved tumour regression and downstaging in the exercise intervention group and should prompt larger studies on this topic. TRIAL REGISTRATION NUMBER: NCT03626610.

Does a high Mandard score really define a poor response to chemotherapy in oesophageal adenocarcinoma?

BACKGROUND: A high Mandard score implies a non-response to chemotherapy in oesophageal adenocarcinoma. However, some patients exhibit tumour volume reduction and a nodal response despite a high score. This study examines survival and recurrence patterns in these patients. METHODS: Clinicopathological factors were analysed using multivariable Cox regression assessing time to death and recurrence. Computed tomography-estimated tumour volume change was examined in a subgroup of consecutive patients. RESULTS: Five hundred and fifty-five patients were included. Median survival was 55 months (Mandard 1-3) and 21 months (Mandard 4 and 5). In the Mandard 4 and 5 group (332 patients), comparison between complete nodal responders and persistent nodal disease showed improved survival (90 vs 18 months), recurrence rates (locoregional 14.75 vs 28.74%, systemic 24.59 vs 48.42%) and circumferential resection margin positivity (22.95 vs 68.11%). Complete nodal response independently predicted improved survival (hazard ratio 0.34 (0.16-0.74). Post-chemotherapy tumour volume reduction was greater in patients with a complete nodal response (-16.3 vs -7.7 cm3, p = 0.033) with no significant difference between Mandard groups. CONCLUSION: Patients with a complete nodal response to chemotherapy have significantly improved outcomes despite a poor Mandard score. High Mandard score does not correspond with a non-response to chemotherapy in all cases and patients with nodal downstaging may still benefit from adjuvant chemotherapy.

The role of surgery after prolonged primary chemotherapy for advanced oesophageal adenocarcinoma.

BACKGROUND: Most patients presenting with oesophageal cancer do so with advanced disease not suitable for surgery. However, there are examples of encouraging survival following surgery in highly selected patients who respond well to chemotherapy. METHODS: This was a retrospective cohort study of patients who presented with advanced but nonvisceral metastatic oesophageal cancer. Consecutive patients on a prolonged primary chemotherapy pathway who underwent surgical resection following a favourable response to chemotherapy were included. Survival and recurrence rates were analysed using Cox regression, providing hazard ratios (HRs) with 95% confidence intervals (CIs). RESULTS: A total of 57 patients included in the cohort operated between 2007 and 2015, the overall median survival was 44 months and the 5-year survival was 42%. Prechemotherapy cN0/cN1 (HR: 0.27, 95% CI: 0.12-0.62) conferred an independent survival advantage compared to cN2 and cN3 disease. Poor differentiation (HR: 2.46, 95% CI: 1.11-5.42), R1 resection (HR: 2.43, 95% CI: 1.14-5.19) and advanced nodal status (HR: 3.28, 95% CI: 1.44-7.47) predicted worse survival on univariable analysis. Poor differentiation (HR: 3.93, 95% CI: 1.62-9.56) was independently associated with poor survival when adjusted for other variables. CONCLUSION: Patients who present with advanced inoperable oesophageal cancer who have a favourable response to chemotherapy represent a limited group of patients who may benefit from surgery.

Adjuvant therapy following neoadjuvant chemotherapy and surgery for oesophageal adenocarcinoma in patients with clear resection margins.

BACKGROUND: The role of adjuvant therapy in patients with oesophagogastric adenocarcinoma treated by neoadjuvant chemotherapy (NAC) and surgery is contentious. In UK practice, surgical resection margin status is often used to classify patients into receiving adjuvant treatment. This study aimed to assess any survival benefit of adjuvant therapy in patients with clear resection margins. METHODS: This was a retrospective collaborative cohort study combining two prospectively collected UK institutional databases of patients with oesophageal adenocarcinoma. Multivariable Cox regression and propensity matched analyses were used to compare overall and recurrence-free survival according to the adjuvant treatment. RESULTS: Of 374 patients with clear resection margins, 221 patients (59%) had no adjuvant treatment, 137 patients (37%) had adjuvant chemotherapy and 16 patients (4%) had adjuvant chemoradiotherapy. For patients who had received NAC (290, 76%), when adjuvant chemotherapy was compared to no adjuvant treatment, hazard ratios (HRs) favoured adjuvant chemotherapy but did not reach independent significance (overall survival [OS] HR 0.65 95% confidence interval [CI] 0.40-1.06; p .0.087). Responders to NAC (Mandard 1-3) were seemingly more likely to demonstrate a survival benefit from adjuvant chemotherapy (HR 0.42 95% CI 0.15-1.11; p .1.081). CONCLUSIONS: Although no independent survival benefit was observed, the point estimates favoured adjuvant treatment, predominantly in patients with chemo-responsive tumours.

Predicting response to neoadjuvant chemotherapy in patients with oesophageal adenocarcinoma.

BACKGROUND: Neoadjuvant chemotherapy is often used prior to surgical resection for oesophageal adenocarcinoma but remains ineffective in a high proportion of patients. The histological Mandard tumour regression grade is used to determine chemoresponse but is not available at the time of treatment decision-making. The aim of this cohort study was to identify factors that predict chemotherapy response prior to surgery. METHODS: A prospectively collected database of patients undergoing surgical resection for oesophageal adenocarcinoma from a high-volume UK institution was used. Patients were subcategorised using pathological tumour response into 'responders' (Mandard grade 1-3) and 'non-responders' (Mandard grade 4 and 5). Multivariable logistic regression analysis was performed to calculate crude and adjusted odds ratios (OR) with 95% confidence intervals (CI) for responder status adjusting for a variety of parameters. Receiver operating characteristic (ROC) curves were calculated. RESULTS: Among 315 patients included, 102 (32%) were responders and 213 (68%) non-responders. A decrease in radiological tumour volume (OR 1.92 95%CI 1.02-3.62; p = 0.05), a 'partial response' RECIST score (OR 7.16 95%CI 1.49-34.36; p = 0.01), a clinically improved dysphagia score (OR 2.79 95%CI 1.05-7.04; p = 0.04) and lymphovascular invasion (OR 0.06 95%CI 0.02-0.13; p = 0.000) influenced responder status. ROC curve analysis for responder status utilising all available parameters had an area under the curve (AUC) of 0.86. CONCLUSION: This study has highlighted the potential for using pre-defined factors to identify those patients who have responded to neoadjuvant chemotherapy, prior to surgical resection, potentially facilitating a more individualised therapeutic approach.

Dopamine and reward hypersensitivity in Parkinson's disease with impulse control disorder.

Impulse control disorders in Parkinson's disease are common neuropsychiatric complications associated with dopamine replacement therapy. Some patients treated with dopamine agonists develop pathological behaviours, such as gambling, compulsive eating, shopping, or disinhibited sexual behaviours, which can have a severe impact on their lives and that of their families. In this study we investigated whether hypersensitivity to reward might contribute to these pathological behaviours and how this is influenced by dopaminergic medication. We asked participants to shift their gaze to a visual target as quickly as possible, in order to obtain reward. Critically, the reward incentive on offer varied over trials. Motivational effects were indexed by pupillometry and saccadic velocity, and patients were tested ON and OFF dopaminergic medication, allowing us to measure the effect of dopaminergic medication changes on reward sensitivity. Twenty-three Parkinson's disease patients with a history of impulse control disorders were compared to 26 patients without such behaviours, and 31 elderly healthy controls. Intriguingly, behavioural apathy was reported alongside impulsivity in the majority of patients with impulse control disorders. Individuals with impulse control disorders also exhibited heightened sensitivity to exogenous monetary rewards cues both ON and OFF (overnight withdrawal) dopamine medication, as indexed by pupillary dilation in anticipation of reward. Being OFF dopaminergic medication overnight did not modulate pupillary reward sensitivity in impulse control disorder patients, whereas in control patients reward sensitivity was significantly reduced when OFF dopamine. These effects were independent of cognitive impairment or total levodopa equivalent dose. Although dopamine agonist dose did modulate pupillary responses to reward, the pattern of results was replicated even when patients with impulse control disorders on dopamine agonists were excluded from the analysis. The findings suggest that hypersensitivity to rewards might be a contributing factor to the development of impulse control disorders in Parkinson's disease. However, there was no difference in reward sensitivity between patient groups when ON dopamine medication, suggesting that impulse control disorders may not emerge simply because of a direct effect of dopaminergic drug level on reward sensitivity. The pupillary reward sensitivity measure described here provides a means to differentiate, using a physiological measure, Parkinson's disease patients with impulse control disorder from those who do not experience such symptoms. Moreover, follow-up of control patients indicated that increased pupillary modulation by reward can be predictive of the risk of future emergence of impulse control disorders and may thereby provide the potential for early identification of patients who are more likely to develop these symptoms.

Two Patients With Severe COVID Pneumonia Treated With the Seraph-100 Microbind Affinity Blood Filter.

We present 2 patients with rapidly escalating oxygen requirements from severe acute respiratory syndrome coronavirus 2 infection (COVID-19) treated with the Seraph100 Microbind Affinity Blood Filter under Emergency Use Authorization from the US Federal Drug Administration. The Seraph100 is an extracorporeal hemoperfusion filter previously demonstrated to remove viral particles and pro-inflammatory cytokines from the blood. Treatment with the Seraph100 filter was associated with a rapid improvement in oxygenation and both patients were discharged from the hospital without supplemental oxygen.

Analysis of outcomes of a transoral circular stapled anastomosis following major upper gastrointestinal cancer resection.

BACKGROUND: Esophageal anastomoses performed following esophagectomy and total gastrectomy are technically challenging with a significant risk of anastomotic leak. A safe, reliable, and easy anastomotic technique is required to improve patient outcomes and reduce morbidity. METHOD: This paper analyses 328 consecutive patients who underwent transoral circular stapled esophageal anastomosis (ORVIL™) from a prospectively collected single-center database between December 2011 and February 2019. RESULTS: Two hundred and twenty-seven esophagectomies and 101 gastrectomies were performed using OrVil™ anastomoses. The mean patient age was 63.7 years. Of 328 consecutive OrVil™-based anastomoses, there were 10 clinically significant anastomotic leaks requiring radiological or operative intervention (3.05%). Twenty-eight (8.54%) patients developed anastomotic stricture, all of which were successfully treated with endoscopic balloon dilatation (a median of 1 dilatation was required per patient). CONCLUSION: The OrVil™ anastomotic technique is reliable and safe to perform. This is the largest reported series of the OrVil™ anastomotic technique to date. Leak rates and anastomotic dilations were similar to other reported series. Based on our experience, we consider the use of the OrVil™ device for reconstruction after major upper GI resection to be safe and reliable.

Spectrum of impulse control behaviours in Parkinson's disease: pathophysiology and management.

Impulse control behaviours (ICBs) are a range of behaviours linked by their reward-based, repetitive natures. They can be precipitated in Parkinson's disease (PD) by dopamine replacement therapy, often with detrimental consequences for patients and caregivers. While now a well-recognised non-motor feature of treated PD, much remains unknown about the influence of risk factors, pathophysiological mechanisms, vulnerability factors for specific types of behaviour and the optimal management strategies. Imaging studies have identified structural and functional changes in striatal and prefrontal brain regions, among others. Gene association studies indicate a role for genetic predisposition to PD-ICB. Clinical observational studies have identified potential modifiable and non-modifiable risk factors. Psychological studies shed light on the neurocognitive domains implicated in PD-ICBs and identify psychosocial determinants that may perpetuate the cycle of impulsive and harm-avoidance behaviours. Based on these results, a range of pharmacological and non-pharmacological management strategies have been trialled in PD-ICBs with varying success. The purpose of this review is to update clinicians on the evidence around the pathophysiology of PD-ICB. We aim to translate our findings into an interpretable biopsychosocial model that can be applied to the clinical assessment and management of individual cases of PD-ICB.