Publications by authors named "Andrew Walter"

Purpose: TRK fusions are detected in less than 2% of central nervous system tumors. There are limited data on the clinical course of affected patients.

Experimental Design: We conducted an international retrospective cohort study of patients with TRK fusion-driven CNS tumors.

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Autonomous methods to align beamlines can decrease the amount of time spent on diagnostics, and also uncover better global optima leading to better beam quality. The alignment of these beamlines is a high-dimensional expensive-to-sample optimization problem involving the simultaneous treatment of many optical elements with correlated and nonlinear dynamics. Bayesian optimization is a strategy of efficient global optimization that has proved successful in similar regimes in a wide variety of beamline alignment applications, though it has typically been implemented for particular beamlines and optimization tasks.

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Introduction: Prognoses for pediatric brain tumors are suboptimal, as even in low-grade tumors, management techniques can lead to damage in the developing brain. Therefore, advanced neuroimaging methods are critical for developing optimal management plans and improving patient care. Magnetic resonance elastography (MRE) has allowed for the characterization of adult gliomas by their mechanical properties, which are uniquely sensitive to the complex interplay of cellularity, vasculature, and interstitium.

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Identifying host genetic factors modulating immune checkpoint inhibitor (ICI) efficacy has been experimentally challenging because of variations in both host and tumor genomes, differences in the microbiome, and patient life exposures. Utilizing the Collaborative Cross (CC) multi-parent mouse genetic resource population, we developed an approach that fixes the tumor genomic configuration while varying host genetics. With this approach, we discovered that response to anti-PD-1 (aPD1) immunotherapy was significantly heritable in four distinct murine tumor models ( between 0.

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Article Synopsis
  • The study aimed to find the best hysterectomy method for large uteri, focusing on the risks and complications associated with different surgical approaches for benign conditions.
  • Researchers analyzed 25 studies, including various types of trials, and found that total vaginal hysterectomy generally had shorter operating times and lower risks of ureteral injury compared to laparoscopic methods.
  • Results indicated that total vaginal hysterectomy is preferable for reducing hospital stay and risk of complications, while robotic-assisted methods showed a lower likelihood of blood transfusion compared to traditional abdominal approaches.
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Scaling up superconducting quantum circuits based on transmon qubits necessitates substantial enhancements in qubit coherence time. Over recent years, tantalum (Ta) has emerged as a promising candidate for transmon qubits, surpassing conventional counterparts in terms of coherence time. However, amorphous surface Ta oxide layer may introduce dielectric loss, ultimately placing a limit on the coherence time.

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The gut microbiome is increasingly recognized to alter cancer risk, progression and response to treatments such as immunotherapy, especially in cutaneous melanoma. However, whether the microbiome influences immune checkpoint inhibitor (ICI) immunotherapy response to non-melanoma skin cancer has not yet been defined. As squamous cell carcinomas (SCC) are in closest proximity to the skin microbiome, we hypothesized that the skin microbiome, which regulates cutaneous immunity, might affect SCC-associated anti-PD1 immunotherapy treatment response.

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Over the past decades, superconducting qubits have emerged as one of the leading hardware platforms for realizing a quantum processor. Consequently, researchers have made significant effort to understand the loss channels that limit the coherence times of superconducting qubits. A major source of loss has been attributed to two level systems that are present at the material interfaces.

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The gut microbiome is increasingly recognized to alter cancer risk, progression, and response to treatments such as immunotherapy, especially in cutaneous melanoma. However, whether the microbiome influences immune checkpoint inhibitor (ICI) immunotherapy response to non-melanoma skin cancer has not yet been defined. As squamous cell carcinomas (SCC) are in closest proximity to the skin microbiome, we hypothesized that the skin microbiome, which regulates cutaneous immunity, might affect SCC-associated anti-PD1 immunotherapy treatment response.

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Curved crystals are a simple but powerful approach to bridge the gap between single crystal surfaces and nanoparticle catalysts, by allowing a rational assessment of the role of active step sites in gas-surface reactions. Using a curved Rh(111) crystal, here, we investigate the effect of A-type (square geometry) and B-type (triangular geometry) atomic packing of steps on the catalytic CO oxidation on Rh at millibar pressures. Imaging the crystal during reaction ignition with laser-induced CO fluorescence demonstrates a two-step process, where B-steps ignite at lower temperature than A-steps.

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Objective: To evaluate the effect of simulation training vs traditional hands-on surgical instruction on learner operative skills and patient outcomes in gynecologic surgeries.

Data Sources: PubMed, Embase, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials from inception to January 12, 2021.

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Article Synopsis
  • The study aimed to determine whether midurethral sling mesh should be partially or totally removed in case of complications.
  • A systematic review and meta-analysis of 45 studies found that partial mesh removal resulted in lower rates of postoperative stress urinary incontinence (SUI) compared to total removal.
  • Both methods showed similar outcomes in terms of pain, bladder obstruction, and other symptoms, with infrequent adverse events reported.
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Exposure to cranial radiotherapy is associated with an increased risk of subsequent CNS neoplasms among childhood, adolescent, and young adult (CAYA) cancer survivors. Surveillance for subsequent neoplasms can translate into early diagnoses and interventions that could improve cancer survivors' health and quality of life. The practice guideline presented here by the International Late Effects of Childhood Cancer Guideline Harmonization Group was developed with an evidence-based method that entailed the gathering and appraisal of published evidence associated with subsequent CNS neoplasms among CAYA cancer survivors.

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  • The study aimed to investigate the clinical outcomes of relapsed medulloblastoma and compare the molecular features of primary and relapsed tumors in children and infants.
  • Researchers analyzed data from two clinical trials, focusing on relapse patterns and survival rates among various molecular subgroups, finding that the type of tumor significantly influenced these outcomes.
  • Results indicated that Group 4 tumors had slower progression and that the effectiveness of post-relapse radiation therapy depended on the patients' prior treatments and age, while some molecular characteristics remained stable across relapses.
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Context: Pituitary blastoma is a rare, dysontogenetic hypophyseal tumor of infancy first described in 2008, strongly suggestive of DICER1 syndrome.

Objective: This work aims to describe genetic alterations, clinical courses, outcomes, and complications in all known pituitary blastoma cases.

Design And Setting: A multi-institutional case series is presented from tertiary pediatric oncology centers.

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The catalytic oxidation of CO on transition metals, such as Pt, is commonly viewed as a sharp transition from the CO-inhibited surface to the active metal, covered with O. However, we find that minor amounts of O are present in the CO-poisoned layer that explain why, surprisingly, CO desorbs at stepped and flat Pt crystal planes at once, regardless of the reaction conditions. Using near-ambient pressure X-ray photoemission and a curved Pt(111) crystal we probe the chemical composition at surfaces with variable step density during the CO oxidation reaction.

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Since the original description of pathogenic germline DICER1 variation underlying pleuropulmonary blastoma (PPB), the spectrum of extrapulmonary neoplasms known to be associated with DICER1 has continued to expand and now includes tumors of the ovary, thyroid, kidney, eye, and brain among other sites. This report documents our experience with another manifestation: a primitive sarcoma that resembles PPB and DICER1-associated sarcoma of the kidney. These tumors are distinguished by their unusual location in the peritoneal cavity, associated with visceral and/or parietal mesothelium.

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Background: "Head Start" III, was a prospective clinical trial using intensive induction followed by myeloablative chemotherapy and autologous hematopoietic cell rescue (AuHCR) to either avoid or reduce the dose/volume of irradiation in young children with medulloblastoma.

Methods: Following surgery, patients received 5 cycles of induction followed by myeloablative chemotherapy using carboplatin, thiotepa, and etoposide with AuHCR. Irradiation was reserved for children >6 years old at diagnosis or with residual tumor post-induction.

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In healthcare, the goal of maximizing value by improving the quality of care and lowering costs has been notoriously challenging to achieve. The fee-for-service model in gynecology and other fields has historically promoted the reduction of nonsurgical or minimally invasive approaches in favor of complex, often morbid procedures. In this review, we seek to define quality and value in the healthcare field and describe strategies that promote quality over production.

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Multiple myeloma is a malignant plasma cell disorder that is rare in the pediatric population, with only approximately 0.3% of cases diagnosed before the age of 30. In this report, we present two patients diagnosed with multiple myeloma between the ages of 12 and 16.

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