Publications by authors named "C Thomas"

7,023 Publications

Evaluation of split-filter dual-energy CT for characterization of urinary stones.

Br J Radiol 2021 May 14:20210084. Epub 2021 May 14.

Radiologie Münster MVZ, Von-Steuben-Str. 10a, 48143 Münster, Germany.

Objective: To assess accuracy of dual-energy computed tomography (DECT) to differentiate uric acid from calcium urinary stones in dual-energy split filter sequential-spiral dual-source acquisition.

Methods: Thirty-four urinary stones (volume 89.0 ± 77.4 mm³; 17 calcium stones, 17 uric acid stones) were scanned in a water-filled phantom using a split-filter equipped CT scanner (SOMATOM Definition Edge, Siemens Healthineers, Forchheim, Germany) in split-filter mode at 120kVp and sequential-spiral mode at 80 and 140kVp. Additional DE scans were acquired at 80 and 140kVp (tin filter) with a dual-source CT scanner (SOMATOM Definition FLASH, Siemens Healthineers). Scans were performed with a CTDIvol of 7.3mGy in all protocols. Urinary stone categorization was based on dual energy ratio (DER) using an automated 3D segmentation. As reference standard, infrared spectroscopy was used to determine urinary stone composition.

Results: All three DECT techniques significantly differentiated between uric acid and calcium stones by attenuation values and DERs ( < 0.001 for all). Split-filter DECT provided higher DERs for uric acid stones, when compared with dual-source and sequential-spiral DECT, and lower DERs for calcified stones when compared with dual-source DECT ( < 0.001 for both), leading to a decreased accuracy for material differentiation.

Conclusion: Split-filter DECT, sequential-spiral DECT and dual-source DECT all allow for the acquisition of DER to classify urinary stones.

Advances In Knowledge: Split-filter DECT enables the differentiation between uric acid and calcium stones despite decreased spectral separation when compared with dual-source and dual-spiral DECT.
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http://dx.doi.org/10.1259/bjr.20210084DOI Listing
May 2021

Use of a sternocleidomastoid muscle flap to protect the carotid artery during laryngectomy.

J Laryngol Otol 2021 May 12:1-4. Epub 2021 May 12.

Department of Otolaryngology - Head and Neck Surgery, University of Alabama at Birmingham, Birmingham, USA.

Objectives: This paper describes a simple method of securing tissue coverage of the great vessels at the initial surgery by rotating the divided sternal heads of the sternocleidomastoid muscle, a routine step during laryngectomy, and approximating them to the prevertebral fascia. The paper presents an illustrated case example where this technique in a salvage laryngectomy repair resulted in a protected vascular axis following a salivary leak.

Results: Since utilising this technique, there has been a marked reduction in the requirement of subsequent flap procedures to protect vessels, and no episodes of threatened or actual carotid blowout.
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http://dx.doi.org/10.1017/S0022215121001249DOI Listing
May 2021

Spectroscopic and biochemical characterization of metallo-β-lactamase IMP-1 with dicarboxylic, sulfonyl, and thiol inhibitors.

Bioorg Med Chem 2021 May 1;40:116183. Epub 2021 May 1.

Department of Chemistry and Biochemistry, Miami University, Oxford, OH 45056, USA. Electronic address:

In an effort to probe the biophysical mechanisms of inhibition for ten previously-reported inhibitors of metallo-β-lactamases (MBL) with MBL IMP-1, equilibrium dialysis, metal analyses coupled with atomic absorption spectroscopy (AAS), native state mass spectrometry (native MS), and ultraviolet-visible spectrophotometry (UV-VIS) were used. 6-(1H-tetrazol-5-yl) picolinic acid (1T5PA), ANT431, D/l-captopril, thiorphan, and tiopronin were shown to form IMP-1/Zn(II)/inhibitor ternary complexes, while dipicolinic acid (DPA) and 4-(3-aminophenyl)pyridine-2,6-dicarboxylic acid (3AP-DPA) stripped some metal from the active site of IMP but also formed ternary complexes. DPA and 3AP-DPA stripped less metal from IMP-1 than from VIM-2 but stripped more metal from IMP-1 than from NDM-1. In contrast to a previous report, pterostilbene does not appear to bind to IMP-1 under our conditions. These results, along with previous studies, demonstrate similar mechanisms of inhibition toward different MBLs for different MBL inhibitors.
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http://dx.doi.org/10.1016/j.bmc.2021.116183DOI Listing
May 2021

The multiple roles of actin-binding proteins at invadopodia.

Int Rev Cell Mol Biol 2021 12;360:99-132. Epub 2021 Apr 12.

Cytoskeleton and Cancer Progression, Department of Oncology, Luxembourg Institute of Health, Luxembourg City, Luxembourg. Electronic address:

Invadopodia are actin-rich membrane protrusions that facilitate cancer cell dissemination by focusing on proteolytic activity and clearing paths for migration through physical barriers, such as basement membranes, dense extracellular matrices, and endothelial cell junctions. Invadopodium formation and activity require spatially and temporally regulated changes in actin filament organization and dynamics. About three decades of research have led to a remarkable understanding of how these changes are orchestrated by sequential recruitment and coordinated activity of different sets of actin-binding proteins. In this chapter, we provide an update on the roles of the actin cytoskeleton during the main stages of invadopodium development with a particular focus on actin polymerization machineries and production of pushing forces driving extracellular matrix remodeling.
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http://dx.doi.org/10.1016/bs.ircmb.2021.03.004DOI Listing
April 2021

A Systematic Review of Discrete Choice Experiments in Oncology Treatments.

Patient 2021 May 5. Epub 2021 May 5.

Evidera, The Ark, 2nd Floor, 201 Talgarth Road, London, W6 8BJ, UK.

Background: As the number and type of cancer treatments available rises and patients live with the consequences of their disease and treatments for longer, understanding preferences for cancer care can help inform decisions about optimal treatment development, access, and care provision. Discrete choice experiments (DCEs) are commonly used as a tool to elicit stakeholder preferences; however, their implementation in oncology may be challenging if burdensome trade-offs (e.g. length of life versus quality of life) are involved and/or target populations are small.

Objectives: The aim of this review was to characterise DCEs relating to cancer treatments that were conducted between 1990 and March 2020.

Data Sources: EMBASE, MEDLINE, and the Cochrane Database of Systematic Reviews were searched for relevant studies.

Study Eligibility Criteria: Studies were included if they implemented a DCE and reported outcomes of interest (i.e. quantitative outputs on participants' preferences for cancer treatments), but were excluded if they were not focused on pharmacological, radiological or surgical treatments (e.g. cancer screening or counselling services), were non-English, or were a secondary analysis of an included study.

Analysis Methods: Analysis followed a narrative synthesis, and quantitative data were summarised using descriptive statistics, including rankings of attribute importance.

Result: Seventy-nine studies were included in the review. The number of published DCEs relating to oncology grew over the review period. Studies were conducted in a range of indications (n = 19), most commonly breast (n =10, 13%) and prostate (n = 9, 11%) cancer, and most studies elicited preferences of patients (n = 59, 75%). Across reviewed studies, survival attributes were commonly ranked as most important, with overall survival (OS) and progression-free survival (PFS) ranked most important in 58% and 28% of models, respectively. Preferences varied between stakeholder groups, with patients and clinicians placing greater importance on survival outcomes, and general population samples valuing health-related quality of life (HRQoL). Despite the emphasis of guidelines on the importance of using qualitative research to inform attribute selection and DCE designs, reporting on instrument development was mixed.

Limitations: No formal assessment of bias was conducted, with the scope of the paper instead providing a descriptive characterisation. The review only included DCEs relating to cancer treatments, and no insight is provided into other health technologies such as cancer screening. Only DCEs were included.

Conclusions And Implications: Although there was variation in attribute importance between responder types, survival attributes were consistently ranked as important by both patients and clinicians. Observed challenges included the risk of attribute dominance for survival outcomes, limited sample sizes in some indications, and a lack of reporting about instrument development processes.

Protocol Registration: PROSPERO 2020 CRD42020184232.
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http://dx.doi.org/10.1007/s40271-021-00520-4DOI Listing
May 2021