A DNA-Based T Cell Receptor Reveals a Role for Receptor Clustering in Ligand Discrimination.

A T cell mounts an immune response by measuring the binding strength of its T cell receptor (TCR) for peptide-loaded MHCs (pMHC) on an antigen-presenting cell. How T cells convert the lifetime of the extracellular TCR-pMHC interaction into an intracellular signal remains unknown. Here, we developed a synthetic signaling system in which the extracellular domains of the TCR and pMHC were replaced with short hybridizing strands of DNA. Remarkably, T cells can discriminate between DNA ligands differing by a single base pair. Single-molecule imaging reveals that signaling is initiated when single ligand-bound receptors are converted into clusters, a time-dependent process requiring ligands with longer bound times. A computation model reveals that receptor clustering serves a kinetic proofreading function, enabling ligands with longer bound times to have disproportionally greater signaling outputs. These results suggest that spatial reorganization of receptors plays an important role in ligand discrimination in T cell signaling.

An optogenetic method for the controlled release of single molecules.

We developed a system for optogenetic release of single molecules in cells. We confined soluble and transmembrane proteins to the Golgi apparatus via a photocleavable protein and released them by short pulses of light. Our method allows for a light dose-dependent delivery of functional proteins to the cytosol and plasma membrane in amounts compatible with single-molecule imaging, greatly simplifying access to single-molecule microscopy of any protein in live cells. We were able to reconstitute ion conductance by delivering BK and LRRC8/volume-regulated anion channels to the plasma membrane. Finally we were able to induce NF-kB signaling in T lymphoblasts stimulated by interleukin-1 by controlled release of a signaling protein that had been knocked out. We observed light-induced formation of functional inflammatory signaling complexes that triggered phosphorylation of the inhibitor of nuclear factor kappa-B kinase only in activated cells. We thus developed an optogenetic method for the reconstitution and investigation of cellular function at the single-molecule level.

Myddosome clustering in IL-1 receptor signaling regulates the formation of an NF-kB activating signalosome.

IL-1 receptor (IL-1R) signaling can activate thresholded invariant outputs and proportional outputs that scale with the amount of stimulation. Both responses require the Myddosome, a multiprotein complex. The Myddosome is required for polyubiquitin chain formation and NF-kB signaling. However, how these signals are spatially and temporally regulated to drive switch-like and proportional outcomes is not understood. During IL-1R signaling, Myddosomes dynamically reorganize into multi-Myddosome clusters at the cell membrane. Blockade of clustering using nanoscale extracellular barriers reduces NF-kB activation. Myddosomes function as scaffolds that assemble an NF-kB signalosome consisting of E3-ubiquitin ligases TRAF6 and LUBAC, K63/M1-linked polyubiquitin chains, phospho-IKK, and phospho-p65. This signalosome preferentially assembles at regions of high Myddosome density, which enhances the recruitment of TRAF6 and LUBAC. Extracellular barriers that restrict Myddosome clustering perturbed the recruitment of both ligases. We find that LUBAC was especially sensitive to clustering with 10-fold lower recruitment to single Myddosomes than clustered Myddosomes. These data reveal that the clustering behavior of Myddosomes provides a basis for digital and analog IL-1R signaling.

Salivary C-reactive protein exhibits a diurnal pattern and relates to biobehavioral health in military men.

C-reactive protein is a systemic inflammatory biomarker that is positively associated with the development of disease. Salivary C-reactive protein (sCRP) has previously been reported to have a diurnal rhythm with higher levels upon awakening and lower levels thereafter. The aims of this study were to evaluate the stability of sCRP across two days, characterize the daily sCRP pattern, compute morning sCRP parameters, and evaluate associations with biobehavioral health in US Navy Explosive Ordnance Disposal (EOD) technicians. Seventy male EOD technicians (age = 34.9 ± 6.5 years) participated in this study, which included a tablet-based survey, measures of health and fitness, and saliva collection. In a free-living setting, participants self-collected saliva on 2 consecutive days at WAKE, WAKE+30, WAKE+60, 4p.m., and 9p.m., for a total of 10 samples. Parameters (e.g., area under the curve) were computed to characterize the morning sCRP magnitude and pattern. Pearson product-moment correlation analyses were used to assess the stability of sCRP samples and parameters across the study period and to examine associations with biobehavioral health. Average sCRP concentrations for the 2-day period were evaluated using an analysis of variance with repeated measures. The stabilities between corresponding time points on Days 1 and 2 were very high (rs = 0.87-.94, all ps ≤ 0.001). sCRP concentrations were highest at WAKE, decreased by 73.6 % at WAKE+30, and then plateaued for the rest of the day. Parameter stabilities were good to excellent (rs = 0.77-.98, all ps ≤ 0.001). We also observed associations between sCRP parameters, self-reported health behaviors, and objective measures of health and fitness. In this study of a military population, we characterized sCRP as diurnal with robust stability across 2 consecutive days, which demonstrates the feasibility of sCRP as a biomarker. These results have significant implications for study methodology and for using sCRP as a marker of dysfunction or disease.

On the multiphoton ionisation photoelectron spectra of phenol.

The phenol molecule is a prototype for non-adiabatic dynamics and the excited-state photochemistry of biomolecules. In this article, we report a joint theoretical and experimental investigation on the resonance enhanced multiphoton ionisation photoelectron (REMPI) spectra of the two lowest ionisation bands of phenol. The focus is on the theoretical interpretation of the measured spectra using quantum dynamics simulations. These were performed by numerically solving the time-dependent Schrödinger equation using the multi-layer variant of the multiconfiguration time-dependent Hartree algorithm together with a vibronic coupling Hamiltonian model. The ionising laser pulse is modelled explicitly within the ionisation continuum model to simulate experimental femtosecond 1+1 REMPI photoelectron spectra. These measured spectra are sensitive to very short lived electronically excited states, providing a rigorous benchmark for our theoretical methods. The match between experiment and theory allows for an interpretation of the features of the spectra at different wavelengths and shows that there are features due to both 'direct' and 'indirect' ionisation, resulting from non-resonant and resonant excitation by the pump pulse.

Risk Prediction Models for Long-Term Survival after Cardiac Surgery: A Systematic Review.

BACKGROUND: The reporting of alternative postoperative measures of quality after cardiac surgery is becoming increasingly important as in-hospital mortality rates continue to decline. This study aims to systematically review and assess risk models designed to predict long-term outcomes after cardiac surgery. METHODS: The MEDLINE and Embase databases were searched for articles published between 1990 and 2020. Studies developing or validating risk prediction models for long-term outcomes after cardiac surgery were included. Data were extracted using checklists for critical appraisal and systematic review of prediction modeling studies. RESULTS: Eleven studies were identified for inclusion in the review, of which nine studies described the development of long-term risk prediction models after cardiac surgery and two were external validation studies. A total of 70 predictors were included across the nine models. The most frequently used predictors were age (n = 9), peripheral vascular disease (n = 8), renal disease (n = 8), and pulmonary disease (n = 8). Despite all models demonstrating acceptable performance on internal validation, only two models underwent external validation, both of which performed poorly. CONCLUSION: Nine risk prediction models predicting long-term mortality after cardiac surgery have been identified in this review. Statistical issues with model development, limited inclusion of outcomes beyond 5 years of follow-up, and a lack of external validation studies means that none of the models identified can be recommended for use in contemporary cardiac surgery. Further work is needed either to successfully externally validate existing models or to develop new models. Newly developed models should aim to use standardized long-term specific reproducible outcome measures.

A systematic review of cardiac surgery clinical prediction models that include intra-operative variables.

BACKGROUND: Most cardiac surgery clinical prediction models (CPMs) are developed using pre-operative variables to predict post-operative outcomes. Some CPMs are developed with intra-operative variables, but none are widely used. The objective of this systematic review was to identify CPMs with intra-operative variables that predict short-term outcomes following adult cardiac surgery. METHODS: Ovid MEDLINE and EMBASE databases were searched from inception to December 2022, for studies developing a CPM with at least one intra-operative variable. Data were extracted using a critical appraisal framework and bias assessment tool. Model performance was analysed using discrimination and calibration measures. RESULTS: A total of 24 models were identified. Frequent predicted outcomes were acute kidney injury (9/24 studies) and peri-operative mortality (6/24 studies). Frequent pre-operative variables were age (18/24 studies) and creatinine/eGFR (18/24 studies). Common intra-operative variables were cardiopulmonary bypass time (16/24 studies) and transfusion (13/24 studies). Model discrimination was acceptable for all internally validated models (AUC 0.69-0.91). Calibration was poor (15/24 studies) or unreported (8/24 studies). Most CPMs were at a high or indeterminate risk of bias (23/24 models). The added value of intra-operative variables was assessed in six studies with statistically significantly improved discrimination demonstrated in two. CONCLUSION: Weak reporting and methodological limitations may restrict wider applicability and adoption of existing CPMs that include intra-operative variables. There is some evidence that CPM discrimination is improved with the addition of intra-operative variables. Further work is required to understand the role of intra-operative CPMs in the management of cardiac surgery patients.

Feasibility and outcomes of a real-world regional lung cancer prehabilitation programme in the UK.

BACKGROUND: Prehabilitation, or multimodality patient optimisation before major treatment, has demonstrated meaningful improvements in patients' outcomes. In the setting of lung cancer surgery, postoperative complications and length of hospital stay are reduced, but there is currently limited access to prehabilitation. Prehab4Cancer (P4C) is an innovative regional programme serving all areas of Greater Manchester (GM). METHODS: The lung cancer P4C service commenced in 2019 as a collaboration between the GM Cancer alliance and 12 leisure and community organisations. Patients planning surgical resection could be referred to receive exercise, nutrition, and well-being assessment and interventions before surgery. We evaluated the programme's feasibility, uptake, and outcomes during the 11 months before COVID-19 restrictions. RESULTS: In total, 377 patients were referred to the lung cancer P4C service from all 11 hospitals in GM. Of the patients reached by telephone, 80.0% (n=280/348) attended initial P4C assessment, which occurred a median of 8 days (inter-quartile range [IQR]: 4-14) after referral. In addition, 74.3% (n=280/377) attended for baseline assessment and 47.7% (n=180/377) completed prehabilitation, attending a median of six sessions (IQR: 4-9). Statistically significant improvements in all objective physiological and subjective functional assessments were observed preoperatively, including a mean increase in the incremental shuttle walk test of 50 m (95% confidence interval: 25-74; P<0.001). CONCLUSIONS: The P4C programme demonstrated feasibility at scale, high uptake, and promising impact on the status of patients with lung cancer before surgery. P4C is the first regional prehabilitation service internationally, and this evaluation provides a framework for implementing similar services in other regions.

Outcomes after Conversion from Video-Assisted Thoracoscopic Lobectomy to Thoracotomy.

BACKGROUND: Lung cancer resections are increasingly being performed via video-assisted thoracoscopic surgery (VATS). Conversion to thoracotomy can occur for many reasons and may affect outcomes. The objective of this study was to investigate the impact of VATS conversion on short- and mid-term outcomes and identify reasons for conversion. METHODS: Consecutive patients undergoing lobectomy for primary non-small cell lung cancer between 2012 and 2019 in a single UK center were included. Primary outcomes were 90-day mortality, intraoperative conversion, and overall survival. Reasons for conversion were defined as bleeding or nonbleeding. Outcomes were compared between groups using univariable analysis. Multivariable logistic regression analysis was performed to identify risk factors for conversion. RESULTS: A total of 2,622 patients were included with 20.6% (n = 541) completing surgery via VATS and 79.4% (n = 2,081) via thoracotomy. The rate of completed VATS surgery increased significantly over time (2012: 6.9%, 2019: 55.1%, p < 0.001). Overall conversion rate was 14.3% (n = 90/631) and has reduced significantly over time (p < 0.001). The rate of conversion due to intraoperative bleeding was 31.1% (n = 28/90). Obesity, male sex, and stage III disease were independent risk factors for conversion. The 90-day mortality rate after conversion was not significantly different from the rate for planned thoracotomy (3.3 vs. 3.4%, p = 0.987). There was no significant difference in overall survival between patients experiencing intraoperative conversion and those undergoing planned thoracotomy (p = 0.135). CONCLUSION: This study demonstrates comparable outcomes for patients undergoing conversion from VATS to those undergoing planned surgery via thoracotomy. It remains unclear if reason for conversion is associated with outcomes.

Adequacy of Mediastinal Lymph Node Sampling in Patients With Lung Cancer Undergoing Lung Resection.

BACKGROUND: Intraoperative mediastinal lymph node sampling (MLNS) is a crucial component of lung cancer surgery. Whilst several sampling strategies have been clearly defined in guidelines from international organizations, reports of adherence to these guidelines are lacking. We aimed to assess our center's adherence to guidelines and determine whether adequacy of sampling is associated with survival. MATERIALS AND METHODS: A single-center retrospective review of consecutive patients undergoing lung resection for primary lung cancer between January 2013 and December 2018 was undertaken. Sampling adequacy was assessed against standards outlined in the International Association for the Study of Lung Cancer 2009 guidelines. Multivariable logistic and Cox proportional hazards regression analyses were used to assess the impact of specific variables on adequacy and of specific variables on overall survival, respectively. RESULTS: A total of 2380 patients were included in the study. Overall adequacy was 72.1% (n= 1717). Adherence improved from 44.8% in 2013 to 85.0% in 2018 (P< 0.001). Undergoing a right-sided resection increased the odds of adequate MLNS on multivariable logistic regression (odds ratio 1.666, 95% confidence interval [CI]: 1.385-2.003, P< 0.001). Inadequate MLNS was not significantly associated with reduced overall survival on log rank analysis (P= 0.340) or after adjustment with multivariable Cox proportional hazards (hazard ratio 0.839, 95% CI 0.643-1.093). CONCLUSIONS: Adherence to standards improved significantly over time and was significantly higher for right-sided resections. We found no evidence of an association between adequate MLNS and overall survival in this cohort. A pressing need remains for the introduction of national guidelines defining acceptable performance.

The Impact of Initial Postoperative Destination on Unplanned Critical Care Admissions After Lung Resection.

OBJECTIVES: Despite an increasing proportion of patients undergoing lung resection being managed postoperatively in a ward-based environment, studies analyzing the impact of initial postoperative destination (IPD) on perioperative outcomes and unplanned critical care admission (UCCA) are lacking. DESIGN: A single-center retrospective review. SETTING: A cardiothoracic surgery center in the Northwest of England. PARTICIPANTS: A total of 3,841 patients between 2012 and 2018. INTERVENTIONS: All patients underwent lung resection. Patients were classified as either IPD ward or IPD critical care. MEASUREMENTS AND MAIN RESULTS: Outcomes assessed included in-hospital and 90-day mortality and UCCA. Differences in mortality rates between groups were assessed using the chi-square test. Multivariate logistic regression analyses were performed to identify variables independently associated with 90-day mortality and UCCA. In total, 23.8% (n = 913) of patients went to critical care as their IPD. Overall in-hospital mortality was 1.6% (n = 62), and 90-day mortality was 2.9% (n = 112). The rate of UCCA was 10.5% (n = 404) and was significantly higher for IPD ward patients compared to IPD critical care patients (11.9% v 6.2%, p < 0.001). The 90-day mortality rates after UCCA were 5.2% (IPD ward) and 19.3% (IPD critical care) (p < 0.001). Advanced age, worse pulmonary function, IPD ward, and timing of surgery were all independently associated with UCCA. CONCLUSIONS: Most patients undergoing lung resection can be managed safely postoperatively in a ward-based environment. Short-term mortality is higher after UCCA, with patients who experience readmission to critical care at the highest risk of death. Patients should receive additional monitoring immediately following discharge from critical care.

Preoperative Anemia is Associated With Worse Long-Term Survival After Lung Cancer Resection: A Multicenter Cohort Study of 5,029 Patients.

OBJECTIVES: Although some evidence to suggest an association between preoperative anemia and reduced overall survival exists, contemporary studies investigating the impact of preoperative anemia on outcomes after resection for primary lung cancer are lacking. DESIGN: A multicenter retrospective review. SETTING: Two tertiary cardiothoracic surgery centers in the Northwest of England. PARTICIPANTS: A total of 5,029 patients between 2012 and 2018. INTERVENTIONS: All patients underwent lung resection for primary lung cancer. Patients were classified as anemic based on the World Health Organization definition. Men with hemoglobin <130 g/L and women with hemoglobin <120 g/L were considered to be anemic. MEASUREMENTS AND MAIN RESULTS: Outcomes assessed included perioperative mortality, 90-day mortality, and overall survival. Multivariate logistic and Cox regression analyses were used to assess the impact of preoperative anemia on 90-day mortality and overall survival, respectively. Overall, preoperatively, 24.0% (n = 1207) of patients were anemic. The 90-day mortality for anemic and nonanemic patients was 5.6% and 3.1%, respectively (p < 0.001). After multivariate adjustment, preoperative anemia was not associated with increased 90-day mortality. However, a log-rank analysis demonstrated reduced overall survival for anemic patients (p < 0.001). After multivariate adjustment, preoperative anemia was found to be independently associated with reduced overall survival (hazard ratio 1.287, 95% confidence interval 1.141-1.451, p < 0.001). CONCLUSIONS: Although anemia was not an independent predictor of short-term outcomes, it was independently associated with significantly reduced survival for patients undergoing resection for lung cancer. Further work is required to understand why anemia reduces long-term survival and whether pathways for anemic patients can be adapted to improve long-term outcomes.

Surgical factors associated with new-onset postoperative atrial fibrillation after lung resection: the EPAFT multicentre study.

PURPOSE OF THE STUDY: Postoperative atrial fibrillation (POAF) is a recognised complication in approximately 10% of major lung resections. In order to best target preoperative treatment, this study aimed at determining the association of incidence of POAF in patients undergoing lung resection to surgical and anatomical factors, such as surgical approach, extent of resection and laterality. STUDY DESIGN: Evaluation of Post-operative Atrial Fibrillation in Thoracic surgery (EPAFT): a multicentre, population-based, retrospective, cross-sectional, observational study including 1367 patients undergoing lung resections between April 2016 and March 2017. The primary outcome was the presence of POAF following resection. POAF was defined as at least one episode of symptomatic or asymptomatic AF confirmed by ECG within 7 days from the thoracic procedure or prior to discharge from the hospital. RESULTS: POAF was observed in 7.4% of patients: 3.1% in minor resection (video-assisted thoracoscopic surgery (VATS): 2.5%; thoracotomy: 3.8%), 9.0% in simple lobectomy (VATS: 7.3%, thoracotomy: 9.9%), 6.0% in complex resection (thoracotomy: 6.3%) and 11.4% in pneumonectomy. POAF was higher in left (4.0%) vs right (2.4%) minor resections, and in left (9.9%) vs right (8.3%) lobectomy, but higher in right (7.5%) complex resections, and the highest in right pneumonectomy (17.6%). No significant variations were observed as per sex, laterality or resected lobes. A positive univariable and multivariable association was observed for increasing age and increasing extent of resection, but not thoracotomy. Median (Q1-Q3) hospital stay was 9 (7-14) days in POAF and 5 (4-7) days in non-AF patients (p<0.001), with an increased cerebrovascular accident burden (p<0.001) and long-term mortality (p<0.001). CONCLUSIONS: Among patients undergoing lung resection, POAF was significantly associated with age, increasing invasiveness of approach and increasing extent of resection. In addition, POAF carried a significant long-term mortality rate and burden of cerebrovascular accident. Appropriate prophylaxis should be targeted at these groups.

Wound hematoma after radial artery harvest caused by digital blood pressure monitoring cuff.

An 85-year-old male developed a hematoma over his radial artery harvest scar 6 weeks after coronary artery bypass grafting. This occurred immediately after his blood pressure was checked using a digital blood pressure monitor with the cuff applied to his left arm. The swelling resolved over the next 5 months. We recommend that patients who have undergone radial artery harvest should have their blood pressure monitored using only the contralateral arm for at least the first 3-6 months after surgery to avoid potential vascular complications.

Greater Fitness Is Associated With Improved Functional Movement Characteristics in Explosive Ordnance Disposal Technicians.

ABSTRACT: Hernández, LM, Coffin, SD, and Taylor, MK. Greater fitness is associated with improved functional movement characteristics in explosive ordnance disposal technicians. J Strength Cond Res 36(6): 1731-1737, 2022-Low fitness and poor functional movement (FM) have been linked to higher musculoskeletal injury risk. The FM Screen (FMS) and Y-Balance Test (YBT) are useful indicators of potential injury risk in military personnel. U.S. Navy Explosive Ordnance Disposal (EOD) technicians are the premier combat force for countering explosive hazards and must operate in austere environments. To safeguard health and mission success, it is critical to assess factors related to injury risk in this specialized military population. This study evaluated the relationship between fitness and FM characteristics in 64 male EOD technicians (mean age ± SD = 34.2 ± 7.0 years). Body fat percentage (BF%), maximum volume of oxygen uptake (V̇o2max), muscular strength, and FM (i.e., FMS, YBT) were assessed. Body fat percentage and V̇o2max were associated with FMS and YBT scores (all p < 0.05). A nonlinear model further revealed that the group with the lowest V̇o2max values had the bottommost FMS and YBT scores (all p < 0.01), but FM scores did not differ among those with a higher V̇o2max, implying a "threshold" effect. No correlations were observed with muscular strength. By characterizing the unique and shared contributions of BF% and V̇o2max, and exploring the nonlinear relationship between V̇o2max and FM, this study expands on accruing data that indicate individuals who are more physically fit have better FM and lower injury risk. Although muscular strength is a critical element of overall fitness, body composition and cardiorespiratory fitness may more strongly influence FM and injury risk.

Descending cervical mediastinitis: the multidisciplinary surgical approach.

PURPOSE: Descending cervical mediastinitis (DCM) is defined as spread of oropharyngeal or odontogenic infection into the mediastinum. It occurs uncommonly and has a high mortality rate. METHODS: Six patients underwent surgery at our centre for DCM between November 2013 and October 2016. Five of six patients underwent drainage of neck collections via a cervical approach, and all six patients subsequently underwent thoracic surgery for drainage of pleural and mediastinal collections. RESULTS: Four patients required further surgical intervention, of which two subsequently required a third thoracic operation. The average length of stay was 73 days (range 4-193). There were no in-hospital deaths and all patients were discharged from our hospital. CONCLUSIONS: Following diagnosis, prompt surgical intervention from ENT and cardiothoracic surgeons is essential. Our experience demonstrates that favourable outcomes can be achieved in patients with DCM when they are managed aggressively and promptly in specialist centres with appropriate multidisciplinary team involvement.

The "yin and yang" of the adrenal and gonadal systems in elite military men.

We recently established daily, free-living profiles of the adrenal hormone cortisol, the (primarily adrenal) anabolic precursor dehydroepiandrosterone (DHEA) and the (primarily gonadal) anabolic hormone testosterone in elite military men. A prevailing view is that adrenal and gonadal systems reciprocally modulate each other; however, recent paradigm shifts prompted the characterization of these systems as parallel, cooperative processes (i.e. the "positive coupling" hypothesis). In this study, we tested the positive coupling hypothesis in 57 elite military men by evaluating associations between adrenal and gonadal biomarkers across the day. Salivary DHEA was moderately and positively coupled with salivary cortisol, as was salivary testosterone. Anabolic processes (i.e. salivary DHEA and testosterone) were also positively and reliably coupled across the day. In multivariate models, salivary DHEA and cortisol combined to account for substantial variance in salivary testosterone concentrations across the day, but this was driven almost exclusively by DHEA. This may reflect choreographed adrenal release of DHEA with testicular and/or adrenal release of testosterone, systemic conversion of DHEA to testosterone, or both. DHEA and testosterone modestly and less robustly predicted cortisol concentrations; this was confined to the morning, and testosterone was the primary predictor. Altogether, top-down co-activation of adrenal and gonadal hormone secretion may complement bottom-up counter-regulatory functions to foster anabolic balance and neuronal survival; hence, the "yin and yang" of adrenal and gonadal systems. This may be an adaptive process that is amplified by stress, competition, and/or dominance hierarchy.

Impact of Pretransplantation (18)F-Fluorodeoxyglucose-Positron Emission Tomography on Survival Outcomes after T Cell-Depleted Allogeneic Transplantation for Hodgkin Lymphoma.

Pretransplant (18)F-fluorodeoxyglucose (FDG) positron emission tomography status is an important prognostic factor for outcomes after autologous stem cell transplantation (SCT) in Hodgkin lymphoma (HL), but its impact on outcomes after allogeneic SCT remains unclear. We retrospectively evaluated outcomes after T cell-depleted allogeneic SCT of 116 patients with nonprogressive HL according to pretransplant Deauville scores. Endpoints were overall survival (OS), progression-free survival (PFS), relapse rate (RR), and nonrelapse-related mortality (NRM). OS, PFS, and RR did not differ significantly between the Deauville 1 to 2 and Deauville 3 to 5 cohorts (OS: 77.5% versus 67.3%, P = .49; PFS: 59.4% versus 55.7%, P = .43; RR: 20.9% versus 22.6%, P = .28 at 4 years). Differences in PFS remained statistically nonsignificant when comparisons were made between Deauville 1 to 3 and Deauville 4 to 5 cohorts (60.9% versus 51.4%, P = .10), and RR remained very similar (21.5% versus 23.8%, P = .42). Multivariate analyses demonstrated trends toward significance for an effect of Deauville score on PFS (hazard ratio 1.82 for Deauville 4 to 5, P = .06) and for number of lines of prior therapy on OS (hazard ratio 2.34 for >5 lines, P = .10). The latter effect appeared to be driven by higher NRM rather than increased RR. Our findings suggest that Deauville score before allogeneic SCT in patients with nonprogressive HL has a relatively modest impact on survival outcomes in comparison with the impact in autologous SCT and that predictive values for the individual patient remain low, indicating that residual FDG-avid disease should not preclude allogeneic SCT. Furthermore, our findings bring into question the importance of attainment of metabolic complete response in this setting if it is at the expense of increasing NRM risk.

Formation of targeted monovalent quantum dots by steric exclusion.

Precise control over interfacial chemistry between nanoparticles and other materials remains a major challenge that limits broad application of nanotechnology in biology. To address this challenge, we used 'steric exclusion' to completely convert commercial quantum dots (QDs) into monovalent imaging probes by wrapping each QD with a functionalized oligonucleotide. We demonstrated the utility of these QDs as modular and nonperturbing imaging probes by tracking individual Notch receptors on live cells.

A feedback loop between dynamin and actin recruitment during clathrin-mediated endocytosis.

Clathrin-mediated endocytosis proceeds by a sequential series of reactions catalyzed by discrete sets of protein machinery. The final reaction in clathrin-mediated endocytosis is membrane scission, which is mediated by the large guanosine triophosphate hydrolase (GTPase) dynamin and which may involve the actin-dependent recruitment of N-terminal containing BIN/Amphiphysin/RVS domain containing (N-BAR) proteins. Optical microscopy has revealed a detailed picture of when and where particular protein types are recruited in the ∼20-30 s preceding scission. Nevertheless, the regulatory mechanisms and functions that underpin protein recruitment are not well understood. Here we used an optical assay to investigate the coordination and interdependencies between the recruitment of dynamin, the actin cytoskeleton, and N-BAR proteins to individual clathrin-mediated endocytic scission events. These measurements revealed that a feedback loop exists between dynamin and actin at sites of membrane scission. The kinetics of dynamin, actin, and N-BAR protein recruitment were modulated by dynamin GTPase activity. Conversely, acute ablation of actin dynamics using latrunculin-B led to a ∼50% decrease in the incidence of scission, an ∼50% decrease in the amplitude of dynamin recruitment, and abolished actin and N-BAR recruitment to scission events. Collectively these data suggest that dynamin, actin, and N-BAR proteins work cooperatively to efficiently catalyze membrane scission. Dynamin controls its own recruitment to scission events by modulating the kinetics of actin and N-BAR recruitment to sites of scission. Conversely actin serves as a dynamic scaffold that concentrates dynamin and N-BAR proteins at sites of scission.