Dynamical topological phase realized in a trapped-ion quantum simulator.

Nascent platforms for programmable quantum simulation offer unprecedented access to new regimes of far-from-equilibrium quantum many-body dynamics in almost isolated systems. Here achieving precise control over quantum many-body entanglement is an essential task for quantum sensing and computation. Extensive theoretical work indicates that these capabilities can enable dynamical phases and critical phenomena that show topologically robust methods to create, protect and manipulate quantum entanglement that self-correct against large classes of errors. However, so far, experimental realizations have been confined to classical (non-entangled) symmetry-breaking orders1-5. In this work, we demonstrate an emergent dynamical symmetry-protected topological phase6, in a quasiperiodically driven array of ten 171Yb+ hyperfine qubits in Quantinuum's System Model H1 trapped-ion quantum processor7. This phase shows edge qubits that are dynamically protected from control errors, cross-talk and stray fields. Crucially, this edge protection relies purely on emergent dynamical symmetries that are absolutely stable to generic coherent perturbations. This property is special to quasiperiodically driven systems: as we demonstrate, the analogous edge states of a periodically driven qubit array are vulnerable to symmetry-breaking errors and quickly decohere. Our work paves the way for implementation of more complex dynamical topological orders8,9 that would enable error-resilient manipulation of quantum information.

Injuries and Health Issues Occurring During Offshore Transoceanic Sailing: A Survey of Recreational Sailors and Cruisers.

INTRODUCTION: Most of the literature on sailing injuries is centered on competitive sailing, often involving a single regatta. The aims of this study were to provide a description of the types of injuries and illnesses sustained during amateur offshore cruising events, estimate their incidence, and investigate potential risk factors for injuries. METHODS: We conducted a cross-sectional survey of self-reported sailing-related injuries and health issues during 4 different events organized by the World Cruising Club between 2014 and 2015. Prior to departure, sailors received an injury or health issue report form to complete during their sailing event. Questionnaires were then collected at the end of each event. Bivariable (Student's t tests and χ2 tests) and mutilvariable logistic regression were used to study the associations among injuries, health issues, and the characteristics of sailors or sailboats. RESULTS: The incidence of injuries and health issues among the respondents was 1.08 and 1.01 per 10,000 nautical miles, respectively. Smaller boats (P<0.001) and crews with less experience with the current boat (P<0.001) were associated with reporting of more injuries. Most of the injuries were reported during favorable weather conditions. Health issues were more frequent on smaller boats and with women (P=0.008), who reported significantly more seasickness (P<0.001), anxiety (P=0.037), and skin rash/fungal infection (P=0.021). CONCLUSIONS: Injuries and health issues are relatively common among amateur offshore recreational sailors, but severe injuries are rare. Smaller boats and having less experience in sailing with the current boat were associated with more injuries. Preventive strategies should include a sailing experience requirement on the boat being sailed for all crew members, increasing the minimum boat size requirement for sailing events, and mandatory first-aid training prior to a cruising event for all crew members.

The pancreatic cancer immune tumor microenvironment is negatively remodeled by gemcitabine while TGF-ß receptor plus dual checkpoint inhibition maintains antitumor immune cells.

Pancreatic ductal adenocarcinoma (PDA) tumors have a highly immunosuppressive desmoplastic tumor microenvironment (TME) where immune checkpoint inhibition (ICI) therapy has been exceptionally ineffective. Transforming growth factor-ß (TGF-ß) receptor activation leads to cancer and immune cell proliferation and phenotype, and cytokine production leading to tumor progression and worse overall survival in PDA patients. We hypothesized that TGF-ß receptor inhibition may alter PDA progression and antitumor immunity in the TME. Here, we used a syngeneic preclinical murine model of PDA to explore the impact of TGF-ß pathway inhibitor galunisertib (GAL), dual checkpoint immunotherapy (anti-PD-L1 and CTLA-4), the chemotherapy gemcitabine (GEM), and their combinations on antitumor immune responses. Blockade of TGF-ß and ICI in immune-competent mice bearing orthotopically injected murine PDA cells significantly inhibited tumor growth and was accompanied by antitumor M1 macrophage infiltration. In contrast, GEM treatment resulted in increased PDA tumor growth, decreased antitumor M1 macrophages, and decreased cytotoxic CD8+ T cell subpopulation compared to control mice. Together, these findings demonstrate the ability of TGF-ß inhibition with GAL to prime antitumor immunity in the TME and the curative potential of combining GAL with dual ICI. These preclinical results indicate that targeted inhibition of TGF-ß may enhance the efficacy of dual immunotherapy in PDA. Optimal manipulation of the immune TME with non-ICI therapy may enhance therapeutic efficacy.

Entanglement from Tensor Networks on a Trapped-Ion Quantum Computer.

The ability to selectively measure, initialize, and reuse qubits during a quantum circuit enables a mapping of the spatial structure of certain tensor-network states onto the dynamics of quantum circuits, thereby achieving dramatic resource savings when simulating quantum systems with limited entanglement. We experimentally demonstrate a significant benefit of this approach to quantum simulation: the entanglement structure of an infinite system-specifically the half-chain entanglement spectrum-is conveniently encoded within a small register of "bond qubits" and can be extracted with relative ease. Using Honeywell's model H0 quantum computer equipped with selective midcircuit measurement and reset, we quantitatively determine the near-critical entanglement entropy of a correlated spin chain directly in the thermodynamic limit and show that its phase transition becomes quickly resolved upon expanding the bond-qubit register.

Determination of the SLAMF1 self-association affinity constant with sedimentation velocity ultracentrifugation.

Signaling lymphocytic activating molecule family member 1 (SLAMF1 or CD150) is a cell surface glycoprotein expressed on various immune populations, regulating cell-cell interactions, activation, differentiation, and inflammatory responses and has been suggested as a potential target for inflammatory diseases. Signaling is believed to be mediated by high-affinity homophilic interactions; the recombinant soluble form of SLAMF1 has optimal activity in the range of 20 µg/mL. This contradicts with a rather weak homo-dimerization binding constant (KD) value reported previously; however, the analytical approach and data analysis suffered from various technical limitations at the time and therefore warrants re-examination. To address this apparent discrepancy, we determined the KD of soluble SLAMF1 using sedimentation velocity analytical ultracentrifuge (SV-AUC). A globally fitted monomer-dimer model properly explains the data from a wide concentration range obtained with both UV and fluorescence detection systems. The analysis suggests the dimerization KD value for human SLAMF1 is 0.48 µM. Additionally, our data show that SLAMF1 self-association is not driven by non-specific binding to glycans supporting the view of specific protein-protein interaction. We anticipate antibody biotherapeutics capable of modulating the biological consequences of SLAMF1 interactions will be readily identified.

The association between copy number aberration, DNA methylation and gene expression in tumor samples.

We systematically studied the association between somatic copy number aberration (SCNA), DNA methylation and gene expression using -omic data from The Cancer Genome Atlas (TCGA) on six cancer types: breast cancer, colon cancer, glioblastoma, leukemia, lower-grade glioma and prostate cancer. A major challenge for such integrated study is that the association between DNA methylation and gene expression is severely confounded by tumor purity and cell type composition, which are often unobserved and difficult to estimate. To overcome this challenge, we developed a method to remove confounding effects by calculating the principal components that span the space of the latent factors. Another intriguing findings of our study is that there could be both positive and negative associations between SCNA and DNA methylation, while the CpGs with negative/positive associations with SCNA are often located around CpG islands/ocean, respectively. A joint study of SCNA, DNA methylation, and gene expression suggest that SCNA often affect DNA methylation and gene expression independently.

Hip muscle atrophy in patients with acetabular labral joint pathology.

Intra-articular hip joint pathology is a source of hip and groin pain in active individuals and is thought to be a precursor to hip osteoarthritis. Limited evidence exists to guide appropriate physiotherapy management for these patients. Identification of which hip muscles are affected may help clinicians to develop effective exercise programs. A cross-sectional observational study in a hospital setting was conducted to investigate the size of individual hip abductor, hip extensor, and hip external rotator muscles in patients with acetabular labral joint pathology compared with age and sex matched healthy subjects. Twelve participants (eight females, four males), aged 20-53 years, with a medical diagnosis of unilateral acetabular labral tear and 12 healthy participants were recruited. Magnetic resonance imaging was used to assess cross-sectional areas of the gluteus minimus, gluteus medius, upper gluteus maximus, lower gluteus maximus, piriformis, and quadratus femoris muscles bilaterally. Gluteus medius muscle cross-sectional area was significantly different between groups (P < 0.01, effect size = 0.92) with muscle size found to be smaller in the pathology group. No differences were found for the other hip muscles (P > 0.05). These findings suggest that hip muscles are not all affected equally by the presence of intra-articular hip joint pathology. Atrophy of specific hip muscles, which are important in hip joint and pelvic stability, may alter hip joint function during gait and functional tasks. Clinicians treating patients with intra-articular hip joint pathology may need to prescribe exercises targeting the specific muscles with demonstrated dysfunction. Clin. Anat. 33:538-544, 2020. © 2019 Wiley Periodicals, Inc.

Long term follow-up of patients with ventricular high rate events detected on remote monitoring of pacemakers.

AIMS: Previous data suggest ventricular high rate episodes (VHREs) on pacemakers are frequent and not associated with overall mortality on short term follow up. We sought to determine whether VHREs are associated with mortality, device upgrade, or change in ejection fraction on long term follow up. METHODS: A single center, retrospective study was performed on 542 patients with permanent pacemakers followed between 2011 and 2013. Follow-up was extended to 2017 for determination of long term outcomes. "True" VHREs were defined as episodes adjudicated to be due to non-sustained ventricular tachycardia on review of electrograms and "false" VHREs were defined as supraventricular arrhythmias or noise. RESULTS: VHRE occurred in 202(37.2%)/542 included patients. True VHRE was detected in 148(27.3%) while 54(10%) had false VHRE. The mean age of the population was 72 ±â€¯15 years and 46% were women. Mean follow-up was 3.3 ±â€¯1.4 years. The baseline characteristics of the true, false and no VHRE patients were similar. There was no difference in all-cause mortality between groups (27% mortality in true VHRE, 33% in false VHRE and 29% in no VHRE). Furthermore, there was no difference between groups with regards to any device upgrade (5% any upgrades in the VHRE, 9% in false VHRE and 5% in no VHRE.) On follow up, EF declined in all groups: -4% vs -2.4% vs -3.5% for true, false and no VHRE. CONCLUSION: VHRE are frequently encountered on remote monitoring of pacemakers and not associated with increased risk of mortality or need for downstream device upgrade.

Phase 2 trial of neoadjuvant chemotherapy and transoral endoscopic surgery with risk-adapted adjuvant therapy for squamous cell carcinoma of the head and neck.

BACKGROUND: The objective of this study was to demonstrate the feasibility and efficacy of induction chemotherapy, surgery, and pathology-guided adjuvant therapy to treat transorally resectable squamous head and neck cancer. METHODS: Patients had squamous head and neck cancer that was resectable by the transoral route and advanced-stage disease (American Joint Committee on Cancer stage III-IV, T3-T4 tumors, and/or positive lymph nodes). They received treatment with weekly carboplatin at an area under the curve of 2, plus paclitaxel 135 mg/m2 , and daily lapatinib 1000mg for 6 weeks followed by surgical resection. Pathology that revealed margins <5 mm, extracapsular extension, N2a of N2b lymph node status, perineural invasion, or lymphovascular space invasion resulted in adjuvant radiotherapy concurrent with weekly cisplatin. Pathology with N2c/N3 lymph node status or positive margins resulted in radiation with bolus cisplatin. The primary endpoint was the clinical response rate to induction chemotherapy, and a key secondary endpoint was feasibility. RESULTS: Toxicity was modest, and 37 of 40 patients completed study procedures as planned. The clinical response rate was 93%, the pathologic complete response rate was 36%, and the clinical response did not predict for a pathologic complete response. No patient on study follow-up has recurred or died. Twenty-nine of 39 patients who underwent surgery avoided radiation. Speech and swallowing function were well preserved. CONCLUSIONS: The study met both its primary efficacy endpoint and the secondary feasibility endpoint. Neoadjuvant, systemic therapy and surgical resection followed by risk-adapted adjuvant therapy resulted in high response rates and excellent long-term outcomes and should be further studied. Cancer 2018;124:2986-92. © 2018 American Cancer Society.

Characterization of therapeutic antibodies in the presence of human serum proteins by AU-FDS analytical ultracentrifugation.

The preclinical characterization of biopharmaceuticals seeks to determine the stability, state of aggregation, and interaction of the antibody/drug with other macromolecules in serum. Analytical ultracentrifugation is the best experimental method to understand these factors. Sedimentation velocity experiments using the AU-FDS system were performed in order to quantitatively characterize the nonideality of fluorescently labeled therapeutic antibodies in high concentrations of human serum proteins. The two most ubiquitous serum proteins are human serum albumin, HSA, and γ-globulins, predominantly IgG. Tracer experiments were done pairwise as a function of HSA, IgG, and therapeutic antibody concentration. The sedimentation coefficient for each fluorescently labeled component as a function of the concentration of the unlabeled component yields the hydrodynamic nonideality (ks). This generates a 3x3 matrix of ks values that describe the nonideality of each pairwise interaction. The ks matrix is validated by fitting both 2:1 mixtures of HSA (1-40 mg/ml) and IgG (0.5-20 mg/ml) as serum mimics, and human serum dilutions (10-100%). The data are well described by SEDANAL global fitting with the ks nonideality matrix. The ks values for antibodies are smaller than expected and appear to be masked by weak association. Global fitting to a ks and K2 model significantly improves the fits.

AUC measurements of diffusion coefficients of monoclonal antibodies in the presence of human serum proteins.

The goal of this work is to develop a preclinical method for quantitative hydrodynamic and thermodynamic analysis of therapeutic proteins in crowded environments like human serum. The method utilizes tracer amounts of fluorescently labeled monoclonal antibodies and the Aviv AU-FDS optical system. We have performed sedimentation velocity experiments as a function of mAb, human serum albumin and human IgG concentration to extract self- and cross-term hydrodynamic nonideality effects. SV measurements are consistently complicated by weak mAb-mAb and mAb-IgG interactions (Wright et al. in Anal Biochem 550:72-83, 2018). In an attempt to explore different approaches we have investigated measurements of diffusion coefficients by traditional synthetic boundary experiments. Here we present a new technique incorporated into SEDANAL that can globally analyze the full time course of synthetic boundary experiments. This approach also utilizes F-mAb against a high concentration of unlabeled carrier protein (HSA or IgG). In principle both diffusion and sedimentation coefficient information can be extracted including hydrodynamic and thermodynamic nonideality. The method can be performed at a traditional low speed (5-7K rpm) or at high speeds. The high speed method can also be used to measure D and s for small molecules like fluorescein (often contaminants of F-HSA and F-mAb). The advantage of synthetic boundary over the standard sedimentation velocity method is that it allows for higher precision determination of diffusion coefficients. The concentration dependence of D can be corrected for hydrodynamic nonideality effects by plotting D * (1 + kijcj) vs total carrier concentration. The slope of the fitted data allows an alternate approach to determine self- and cross-term thermodynamic nonideality. This method can also explore cross-term diffusion coefficient effects. These results are compared to dynamic light scattering approaches which are limited to kD determinations for solutions of pure protein.

Oversensing of transthoracic excitation stimuli in contemporary pacemakers.

BACKGROUND: Transthoracic impedance measurements (TIM) is primarily used for minute ventilation rate adaptive sensors in pacemakers. With elevated impedance, the TIM electrical signal itself is oversensed, causing device malfunction. OBJECTIVE: We report an increased incidence of TIM oversensing. METHOD: Retrospective chart review. We review existing records of 18 patients who have demonstrated device malfunction with TIM oversensing. RESULTS: We have found a 1.8% incidence of TIM-related oversensing in our patient population of 959 patients with contemporary Boston Scientific (Marlborough, MA, USA) pacemakers and cardiac resynchronization therapy pacemakers. One patient experienced a syncopal episode. CONCLUSION: Oversensing with pacing inhibition is apparent with the potential of adverse effects to patients.

GDF11 does not rescue aging-related pathological hypertrophy.

RATIONALE: Growth differentiation factor 11 (GDF11) is a member of the transforming growth factor-ß super family of secreted factors. A recent study showed that reduced GDF11 blood levels with aging was associated with pathological cardiac hypertrophy (PCH) and restoring GDF11 to normal levels in old mice rescued PCH. OBJECTIVE: To determine whether and by what mechanism GDF11 rescues aging dependent PCH. METHODS AND RESULTS: Twenty-four-month-old C57BL/6 mice were given a daily injection of either recombinant (r) GDF11 at 0.1 mg/kg or vehicle for 28 days. rGDF11 bioactivity was confirmed in vitro. After treatment, rGDF11 levels were significantly increased, but there was no significant effect on either heart weight or body weight. Heart weight/body weight ratios of old mice were not different from 8- or 12-week-old animals, and the PCH marker atrial natriuretic peptide was not different in young versus old mice. Ejection fraction, internal ventricular dimension, and septal wall thickness were not significantly different between rGDF11 and vehicle-treated animals at baseline and remained unchanged at 1, 2, and 4 weeks of treatment. There was no difference in myocyte cross-sectional area rGDF11 versus vehicle-treated old animals. In vitro studies using phenylephrine-treated neonatal rat ventricular myocytes, to explore the putative antihypertrophic effects of GDF11, showed that GDF11 did not reduce neonatal rat ventricular myocytes hypertrophy, but instead induced hypertrophy. CONCLUSIONS: Our studies show that there is no age-related PCH in disease-free 24-month-old C57BL/6 mice and that restoring GDF11 in old mice has no effect on cardiac structure or function.

Omega 3 polyunsaturated fatty acids and the treatment of depression.

Depression is a common, recurrent, and debilitating illness that has become more prevalent over the past 100 years. This report reviews the etiology and pathophysiology of depression, and explores the role of omega 3 polyunsaturated fatty acids (n-3 PUFA) as a possible treatment. In seeking to understand depression, genetic factors and environmental influences have been extensively investigated. Research has led to several hypotheses for the pathophysiological basis of depression but a definitive pathogenic mechanism, or group thereof, has hitherto remained equivocal. To date, treatment has been based on the monoamine hypothesis and hence, selective serotonin reuptake inhibitors have been the most widely used class of medication. In the last decade, there has been considerable interest in n-3 PUFAs and their role in depression. These fatty acids are critical for development and function of the central nervous system. Increasing evidence from epidemiological, laboratory, and randomized placebo-controlled trials suggests deficiency of dietary n-3 PUFAs may contribute to development of mood disorders, and supplementation with n-3 PUFAs may provide a new treatment option. Conclusions based on systematic reviews and meta-analyses of published trials to date vary. Research into the effects of n-3 PUFAs on depressed mood is limited. Furthermore, results from such have led to conflicting conclusions regarding the efficacy of n-3 PUFAs in affecting reduction in symptoms of depression. PUFAs are generally well tolerated by adults and children although mild gastrointestinal effects are reported. There is mounting evidence to suggest that n-3 PUFAs play a role in depression and deserve greater research efforts.

Statistical significance for hierarchical clustering.

Cluster analysis has proved to be an invaluable tool for the exploratory and unsupervised analysis of high-dimensional datasets. Among methods for clustering, hierarchical approaches have enjoyed substantial popularity in genomics and other fields for their ability to simultaneously uncover multiple layers of clustering structure. A critical and challenging question in cluster analysis is whether the identified clusters represent important underlying structure or are artifacts of natural sampling variation. Few approaches have been proposed for addressing this problem in the context of hierarchical clustering, for which the problem is further complicated by the natural tree structure of the partition, and the multiplicity of tests required to parse the layers of nested clusters. In this article, we propose a Monte Carlo based approach for testing statistical significance in hierarchical clustering which addresses these issues. The approach is implemented as a sequential testing procedure guaranteeing control of the family-wise error rate. Theoretical justification is provided for our approach, and its power to detect true clustering structure is illustrated through several simulation studies and applications to two cancer gene expression datasets.

Feasibility of establishing an Australian ACL registry: a pilot study by the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR).

PURPOSE: Rupture of the anterior cruciate ligament (ACL) is a common and debilitating injury that impacts significantly on knee function and risks the development of degenerative arthritis. The outcome of ACL surgery is not monitored in Australia. The optimal treatment is unknown. Consequently, the identification of best practice in treating ACL is crucial to the development of improved outcomes. The Australian Knee Society (AKS) asked the Australian Orthopaedic Association (AOA) to consider establishing a national ACL registry. As a first step, a pilot study was undertaken by the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) to test the hypothesis that collecting the required information in the Australian setting was possible. METHODS: Surgeons completed an operative form which provided comprehensive information on the surgery undertaken. Patients provided pre- and post-operative questionnaires including the Knee Injury and Osteoarthritis Outcome Score (KOOS) and the Marx Activity Scale (MA Scale). The number of ACL procedures undertaken at each hospital during the recruitment period was compared against State Government Health Department separation data. RESULTS: A total of 802 patients were recruited from October 2011 to January 2013. The overall capture rate for surgeon-derived data was 99%, and the capture rate for the pre-operative patient questionnaire was 97.9%. At 6 months, patient-reported outcomes were obtained from 55% of patients, and 58.5% of patients at 12 months. When checked against State Government Health Department separation data, 31.3% of procedures undertaken at each study hospital were captured in the study. CONCLUSION: It is possible to collect surgeon-derived and pre-operative patient-reported data, following ACL reconstruction in Australia. The need to gain patient consent was a limiting factor to participation. When patients did consent to participate in the study, we were able to capture nearly 100% of surgical procedures. Patient consent would not be an issue in for a national registry where inclusion is automatic unless the patient wishes to opt out. The collection of post-operative patient-reported outcome measures (PROMs) is more problematic, due to an insufficient proportion of individuals providing patient-reported outcomes. Alternative outcome measures are required for an ACL registry in Australia to be successfully implemented. LEVEL OF EVIDENCE: Diagnostic, Level III.

Using the galactose-α-1,3-galactose enzyme-linked immunosorbent assay to predict anaphylaxis in response to cetuximab.

BACKGROUND: Cetuximab is a monoclonal antibody against epidermal growth factor receptor with activity against head and neck cancer and colorectal cancer. Anaphylaxis in response to cetuximab is a significant clinical problem in the Southeastern United States with a grade 3/4 infusion reaction rate of 14%. Previous retrospective data have suggested that the presence of preformed immunoglobulin E antibodies against galactose-α-1,3-galactose in serum can predict anaphylaxis in response to cetuximab. METHODS: Sixty patients were prospectively screened as part of the entry criteria for a phase 2 study of neoadjuvant carboplatin, nab-paclitaxel, and cetuximab. Patients were recruited at 2 academic medical centers known to have high anaphylaxis rates: the University of North Carolina and Vanderbilt. Only patients with a negative laboratory result were treated on the clinical protocol. RESULTS: No patient experienced anaphylaxis; the negative predictive value was thus 100%. Other than smoking history, the demographics were similar for assay-positive subjects and assay-negative subjects. CONCLUSIONS: Subjects with a negative test result can be safely treated with cetuximab. Further research is required regarding the optimal cutoff for positivity and the positive predictive value. Cancer 2016;122:1697-701. © 2016 American Cancer Society.

Capecitabine and lapatinib for the first-line treatment of metastatic/recurrent head and neck squamous cell carcinoma.

BACKGROUND: The combination of cisplatin, 5-fluorouracil, and cetuximab is a standard treatment for patients with recurrent/metastatic head and neck cancer, with a high rate of toxicity. Identifying less toxic, equally effective regimens is imperative. Therefore, in the current study, the authors investigated first-line treatment with an all-oral regimen of capecitabine and lapatinib. METHODS: Patients were required to have incurable head and neck cancer of any primary site other than the nasopharynx, an Eastern Cooperative Oncology Group performance status (ECOG PS) of 0 to 2, and no prior exposure to capecitabine or lapatinib. Subjects were treated with capecitabine at a dose of 1000 mg/m(2) twice daily and lapatinib at a dose of 1250 mg daily. Capecitabine was administered for 14 days of each 21-day cycle for 4 cycles. Lapatinib was administered daily until disease progression. The primary outcome was overall survival. RESULTS: A total of 44 subjects were accrued between November 13, 2009 and April 29, 2014. Approximately 38.6% of the sample had an ECOG PS of 0, 52.3% had an ECOG PS of 1, and 9.1% had an ECOG PS of 2. Approximately 81.8% were male and the median age of the patients was 62 years. Prior attempts at curative treatment with chemotherapy had been used in 68.2% of patients (platinum was used in 55.8%). There was no grade 5 toxicity noted (toxicity was graded according to National Cancer Institute Common Terminology Criteria for Adverse Events [version 3.0]). The most common adverse events were diarrhea (18.2% of patients with grade 3) and rash (13.6% of patients with grade 3). The primary objective was met; the median overall survival was 10.7 months (90% confidence interval [90% CI], 8.7-12.9 months). The overall response rate was 25% (90% CI, 15%-38%). The median progression-free survival was 4.2 months (90% CI, 3.6-5.1 months). The results were not substantially different when subdivided by p16 status. Only 2 patients were positive for human epidermal growth factor receptor 2 by immunohistochemistry. CONCLUSIONS: The current study met its primary objective of survival comparable to the combination of cisplatin, 5-FU and cetuximab regimen, and the toxicity of this all-oral regimen was tolerable. Cancer 2016;122:2350-2355. © 2016 American Cancer Society.

Differential Binding Activity of TGF-ß Family Proteins to Select TGF-ß Receptors.

Growth differentiation factor-11 (GDF11) and myostatin (MSTN) are highly related transforming growth factor-ß (TGF-ß) ligands with 89% amino acid sequence homology. They have different biologic activities and diverse tissue distribution patterns. However, the activities of these ligands are indistinguishable in in vitro assays. SMAD2/3 signaling has been identified as the canonical pathway for GDF11 and MSTN, However, it remains unclear which receptor heterodimer and which antagonists preferentially mediate and regulate signaling. In this study, we investigated the initiation and regulation of GDF11 and MSTN signaling at the receptor level using a novel receptor dimerization detection technology. We used the dimerization platform to link early receptor binding events to intracellular downstream signaling. This approach was instrumental in revealing differential receptor binding activity within the TGF-ß family. We verified the ActR2b/ALK5 heterodimer as the predominant receptor for GDF11- and MSTN-induced SMAD2/3 signaling. We also showed ALK7 specifically mediates activin-B signaling. We verified follistatin as a potent antagonist to neutralize both SMAD2/3 signaling and receptor dimerization. More remarkably, we showed that the two related antagonists, growth and differentiation factor-associated serum protein (GASP)-1 and GASP2, differentially regulate GDF11 (and MSTN) signaling. GASP1 blocks both receptor dimerization and downstream signaling. However, GASP2 blocks only downstream signaling without interference from receptor dimerization. Our data strongly suggest that physical binding of GDF11 (and MSTN) to both ActR2b and ALK5 receptors is required for initiation of signaling.

Implantable Cardioverter Defibrillator Programming Characteristics, Shocked Rhythms, and Survival Among Patients Under Thirty Years of Age.

INTRODUCTION: Indications for implantable cardioverter defibrillators (ICDs) in young patients have expanded and differ from those in older adults. We sought to provide descriptive characteristics and data regarding ICD therapy and outcomes among younger and older ICD recipients. METHODS AND RESULTS: Demographics, device type and programming, remotely transmitted data, shock events, and survival were compared among younger (≤30 years) and older (>30 years) cohorts with ICDs from a single manufacturer followed on a remote network. The younger cohort included 904 patients (1.6% of all implants). This group had more females (46% vs. 25%; P < 0.01), single-coil leads (21% vs. 4%; P < 0.01), and single-chamber devices (46% vs. 34%; P < 0.01). Shock incidence was higher (40% younger vs. 32% older at 4 years; P < 0.01) and survival was better over comparable follow-up (88% vs. 72%; P < 0.01). Remote monitoring was associated with improved survival in both groups (93% vs. 86% ≤ 30 years, P < 0.01; 73% vs. 66% > 30 years, P < 0.01). Shock for polymorphic ventricular tachycardia/fibrillation (VT/VF) was more frequent in younger patients (12% vs. 5%; P < 0.01); 39% of all shocks were inappropriate. A 10-fold increased risk of mortality was seen among young patients with shocks for atrial fibrillation/flutter (AF/AFL). CONCLUSIONS: Differences in survival, shock incidence, and prognostic significance of VT/VF and AF/AFL exist between younger and older ICD recipients. These suggest distinct differences in myocardial substrates and diseases that ultimately impact ICD management.