Rational Design of a Circularly Permuted Flavin-Based Fluorescent Protein.

Flavin-based fluorescent proteins are oxygen-independent reporters that hold great promise for imaging anaerobic and hypoxic biological systems. In this study, we explored the feasibility of applying circular permutation, a valuable method for the creation of fluorescent sensors, to flavin-based fluorescent proteins. We used rational design and structural data to identify a suitable location for circular permutation in iLOV, a flavin-based reporter derived from A.

Comparing dosimetry of locally advanced cervical cancer patients treated with 3 versus 4 fractions of MRI-guided brachytherapy.

Purpose: To demonstrate the feasibility of treating cervical cancer patients with MRI-guided brachytherapy (MRgBT) using 24 Gy in 3 fractions (F) versus a standard, more resource-intensive regimen of 28 Gy in 4F, and its ability to meet EMBRACE II planning aims.

Methods And Materials: A retrospective review of 224 patients with FIGO Stage IB-IVA cervical cancer treated with 28 Gy/4F (n = 91) and 24 Gy/3F (n = 133) MRgBT between 2016-2021 was conducted. Multivariable linear regression models were fitted to compare dosimetric parameters between the two groups, adjusting for CTV and T stage.

Virtual Reality for Evaluating Prosthetic Hand Control Strategies: A Preliminary Report.

Improving prosthetic hand functionality is critical in reducing abandonment rates and improving the amputee's quality of life. Techniques such as joint force estimation and gesture recognition using myoelectric signals could enable more realistic control of the prosthetic hand. To accelerate the translation of these advanced control strategies from lab to clinic, We created a virtual prosthetic control environment that enables rich user interactions and dexterity evaluation.

Repeatability and reproducibility of MRI-based radiomic features in cervical cancer.

Purpose: The aims of this study are to evaluate the stability of radiomic features from T2-weighted MRI of cervical cancer in three ways: (1) repeatability via test-retest; (2) reproducibility between diagnostic MRI and simulation MRI; (3) reproducibility in inter-observer setting.

Materials And Methods: This retrospective cohort study included FIGO stage IB-IVA cervical cancer patients treated with chemoradiation between 2005 and 2014. There were three cohorts of women corresponding to each aim of the study: (1) 8 women who underwent test-retest MRI; (2) 20 women who underwent MRI on different scanners (diagnostic and simulation MRI); (3) 34 women whose diagnostic MRIs were contoured by three observers.

Patient-reported sexual adjustment after definitive chemoradiation and MR-guided brachytherapy for cervical cancer.

Purpose: The treatment of locally advanced cervical cancer with definitive chemoradiation (CRT) is associated with vaginal toxicity and altered sexual satisfaction. This prospective study assessed patient-reported sexual adjustment, vaginal dosimetry, and physician-reported vaginal toxicity in patients with cervical cancer treated with CRT and MR-guided brachytherapy (BT).

Materials And Methods: Between 2008 and 2010, International Federation of Gynecologists and Obstetricians stage IB-IVA patients with cervical cancer receiving definitive CRT were enrolled in a feasibility study assessing MR-guided BT.

Measurement of Tumor Hypoxia in Patients With Locally Advanced Cervical Cancer Using Positron Emission Tomography with F-Fluoroazomyin Arabinoside.

Purpose: To assess cervical tumor hypoxia using the hypoxia tracer F-fluoroazomycin arabinoside (F-FAZA) and compare different reference tissues and thresholds for quantifying tumor hypoxia.

Methods And Materials: Twenty-seven patients with cervical cancer were studied prospectively by positron emission tomography (PET) imaging with F-FAZA before starting standard chemoradiation. The hypoxic volume was defined as all voxels within a tumor (T) with standardized uptake values (SUVs) greater than 3 standard deviations from the mean gluteus maximus muscle SUV value (M) or SUVs greater than 1 to 1.

Comparison of dosimetric parameters derived from whole organ and wall contours for bladder and rectum in cervical cancer patients treated with intracavitary and interstitial brachytherapy.

For volumes up to 2 cm of the bladder and possibly up to 5 cm of the rectum, doses computed from the whole organ were good estimates of the doses in the wall in cervix brachytherapy, and there were no significant differences between patients treated with or without interstitial needles.

Technique adaptation, strategic replanning, and team learning during implementation of MR-guided brachytherapy for cervical cancer.

Purpose: MR-guided brachytherapy (MRgBT) with interstitial needles is associated with improved outcomes in cervical cancer patients. However, there are implementation barriers, including magnetic resonance (MR) access, practitioner familiarity/comfort, and efficiency. This study explores a graded MRgBT implementation strategy that included the adaptive use of needles, strategic use of MR imaging/planning, and team learning.

Intermediate dose-volume parameters and the development of late rectal toxicity after MRI-guided brachytherapy for locally advanced cervix cancer.

Purpose: The dose delivered to the most exposed 2 cm [Formula: see text] of the rectum and bladder is predictive of late rectal and bladder toxicity in cervix cancer patients. We investigated the predictive value of intermediate doses to the rectum and bladder for late rectal/bladder toxicity after MRI-guided brachytherapy for patients with locally advanced cervix cancer.

Methods And Materials: Toxicity was prospectively graded using Common Toxicity Criteria for Adverse Events v4.

A prospective study of DWI, DCE-MRI and FDG PET imaging for target delineation in brachytherapy for cervical cancer.

Background And Purpose: We examined the utility of dynamic contrast-enhanced MRI (DCE-MRI), diffusion-weighted MRI (DWI), and FDG-PET imaging for brachytherapy target delineation in patients with locally advanced cervical cancer.

Materials And Methods: Twenty-two patients had DWI, DCE-MRI, and FDG-PET/CT scans after brachytherapy applicator insertion, in addition to standard T2-weighted (T2w) 3T MRI. Gross tumor volume (GTV) and high-risk clinical target volume (HRCTV) were contoured first on T2w images, and then modified if indicated upon review of DWI/DCE-MRI/FDG-PET images by two observers.

Automated Delineation of the Normal Urinary Bladder on Planning CT and Cone Beam CT.

Purpose: To quantify the volumetric effect of delineation variability when using manual versus semiautomated tools to contour the normal bladder on planning computed tomography (CT) and cone beam CT.

Methods: Following research ethics board approval, 10 prostate cancer patients were selected. For each patient, one pretreatment cone beam CT (CBCT) was randomly selected from the first treatment week and registered to the planning CT (planCT).

Association of Apparent Diffusion Coefficient with Disease Recurrence in Patients with Locally Advanced Cervical Cancer Treated with Radical Chemotherapy and Radiation Therapy.

Purpose: To investigate whether volumetrically derived apparent diffusion coefficient (ADC) from pretreatment diffusion-weighted (DW) magnetic resonance (MR) imaging is associated with disease recurrence in women with locally advanced cervical cancer treated with chemotherapy and radiation therapy.

Materials And Methods: An ethics board-approved, retrospective study was conducted in 85 women with stage IB-IVA cervical cancer treated with chemo- and radiation therapy in 2009-2013. All patients underwent MR imaging for staging, including T2-weighted and DW MR imaging series, by using a 1.

Dosimetrically triggered adaptive intensity modulated radiation therapy for cervical cancer.

Purpose: The widespread use of intensity modulated radiation therapy (IMRT) for cervical cancer has been limited by internal target and normal tissue motion. Such motion increases the risk of underdosing the target, especially as planning margins are reduced in an effort to reduce toxicity. This study explored 2 adaptive strategies to mitigate this risk and proposes a new, automated method that minimizes replanning workload.

Hybrid adaptive radiotherapy with on-line MRI in cervix cancer IMRT.

Purpose: Substantial organ motion and tumor shrinkage occur during radiotherapy for cervix cancer. IMRT planning studies have shown that the quality of radiation delivery is influenced by these anatomical changes, therefore the adaptation of treatment plans may be warranted. Image guidance with off-line replanning, i.

Tumor and normal tissue dosimetry changes during MR-guided pulsed-dose-rate (PDR) brachytherapy for cervical cancer.

Background And Purpose: To analyze systematic changes in tumor and normal tissue anatomy and dosimetry using serial MR imaging during pulsed dose rate brachytherapy (PDR BT) for cervical cancer.

Material And Methods: Forty-three patients with cervical cancer underwent MR-guided PDR BT using an intrauterine applicator alone after external beam radiotherapy. MR imaging was repeated on days 2 and 3 of treatment and the day 1 plan was applied to the re-contoured volumes.

Auto-segmentation of normal and target structures in head and neck CT images: a feature-driven model-based approach.

Purpose: Intensity modulated radiation therapy (IMRT) allows greater control over dose distribution, which leads to a decrease in radiation related toxicity. IMRT, however, requires precise and accurate delineation of the organs at risk and target volumes. Manual delineation is tedious and suffers from both interobserver and intraobserver variability.

The effect of delineation method and observer variability on bladder dose-volume histograms for prostate intensity modulated radiotherapy.

Purpose: To quantify the effect of delineation method on bladder DVH, observer variability (OV) and contouring time for prostate IMRT plans.

Materials And Methods: Planning CT scans and IMRT plans of 30 prostate cancer patients were anonymized. For 20 patients, 1 observer delineated the bladder using 9 methods.

Automated weekly replanning for intensity-modulated radiotherapy of cervix cancer.

Purpose: The adoption of intensity-modulated radiotherapy (IMRT) to treat cervical malignancies has been limited in part by complex organ and tumor motion during treatment. This study explores the limits of a highly adaptive, small-margin treatment scenario to accommodate this motion. In addition, the dosimetric consequences of organ and tumor motion are modeled using a combination of deformable registration and fractional dose accumulation techniques.

The development of EERA: software for assessing rheumatic joint erosions.

Objective: The principal aim of this study was to create a segmentation program, to be used by nonmusculoskeletal or junior fellows, that defines the bones in the metacarpophalangeal joint in a dynamic 3-dimensional image that will lead to higher inter-reader agreement of bone erosion scores.

Methods: The second to fifth metacarpal head and phalangeal bases of 15 participants were rated according to the Rheumatoid Arthritis Magnetic Resonance Imaging Scoring system by one trained and one untrained reader. Two comparisons were made.

Pelvic radiotherapy for cancer of the cervix: is what you plan actually what you deliver?

Purpose: Whole pelvic intensity-modulated radiotherapy (IMRT) is increasingly being used to treat cervix cancer and other gynecologic tumors. However, tumor and normal organ movement during treatment can substantially detract from the benefits of this approach. This study explored the effect of internal anatomic changes on the dose delivered to the tumor and organs at risk using a strategy integrating deformable soft-tissue modeling with simulated dose accumulation.