Fluorine-18 is the most widely used positron emission tomography (PET) radionuclide currently in clinical application, due to its optimal nuclear properties. The synthesis of F-labeled radiotracers often requires harsh reaction conditions, limiting the use of sensitive bio- and macromolecules as precursors for direct radiolabeling with fluorine-18. We aimed to develop a milder and efficient in vitro and in vivo labeling method for trans-cyclooctene (TCO) functionalized proteins, through the bioorthogonal inverse-electron demand Diels-Alder (IEDDA) reaction with fluorine-18 radiolabeled tetrazine ([F]SiFA-Tz). Here, we used TCO-modified bovine serum albumin (BSA) as the model protein, and isotopic exchange (IE) (F/F) chemistry as the labeling strategy. The radiolabeling of albumin-TCO with [F]SiFA-Tz ([F]), providing [F]fluoroalbumin ([F]) in high radiochemical yield (99.1 ± 0.2%, = 3) and a molar activity (MA) of 1.1 GBq/µmol, confirmed the applicability of [F] as a quick in vitro fluorination reagent for the TCO functionalized proteins. While the biological evaluation of [F] demonstrated defluorination in vivo, limiting the utility for pretargeted applications, the in vivo stability of the radiotracer was dramatically improved when [F] was used for the radiolabeling of albumin-TCO ([F]) in vitro, prior to administration. Due to the detected defluorination in vivo, structural optimization of the prosthetic group for improved stability is needed before further biological studies and application of pretargeted PET imaging.
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http://dx.doi.org/10.3390/molecules25051208 | DOI Listing |
Hip Int
January 2025
Department of Orthopaedics and Traumatology, Istanbul School of Medicine, Istanbul University, Istanbul, Turkey.
Background: A population-based study delineating the epidemiologic, clinical, and treatment characteristics of femoral neck fractures (FNFs) in elderly patients has not yet been conducted in Turkey. In this nationwide study, the epidemiologic, clinical, and treatment characteristics of patients aged ⩾65 years with FNFs who underwent osteosynthesis, hemiarthroplasty (HA), or total hip arthroplasty (THA) were examined.
Methods: Patients aged ⩾65 years with FNFs were identified in this retrospective, nationwide study.
Background: There has been an increase in both primary anatomic (aTSA) and reverse total shoulder arthroplasty (rTSA) over the last decade, with rates peaking for patients aged 75 years and older. Despite aTSA being the mainstay of treatment for patients with glenohumeral arthritis in the absence of rotator cuff insufficiency, there has been an upward trend of rTSA utilization in the elderly due to concerns about rotator cuff integrity, regardless of deformity. The purpose of this study is to evaluate outcomes including pain, function, range of motion, satisfaction, and complications in patients 80 years or older following primary anatomic and reverse total shoulder arthroplasty for osteoarthritis without full thickness rotator cuff tears.
View Article and Find Full Text PDFPolymers (Basel)
January 2025
Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, MD 21201, USA.
Background: Polymethyl methacrylate (PMMA) is ideal for denture bases but is prone to biofilm accumulation, leading to denture stomatitis (DS), often involving . Dimethylaminohexadecyl methacrylate (DMAHDM) and 2-methacryloyloxyethyl phosphorylcholine (MPC) are introduced into dental materials for their antimicrobial and protein-repellent properties. This study investigates the effects of incorporating dimethylaminohexadecyl methacrylate (DMAHDM) and 2-methacryloyloxyethyl phosphorylcholine (MPC) into heat-polymerized (HP) and 3D-printed (3DP) denture base resins on microbial adhesion and cytotoxicity.
View Article and Find Full Text PDFPharmaceuticals (Basel)
January 2025
Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Wilhelm-Johnen-Str., 52428 Jülich, Germany.
The radiotracer [F]JK-PSMA-7, a prostate cancer imaging agent for positron emission tomography (PET), was previously synthesized by indirect radiofluorination using an F-labeled active ester as a prosthetic group, which had to be isolated and purified before it could be linked to the pharmacologically active Lys-urea-Glu motif. Although this procedure could be automated on two-reactor modules like the GE TRACERLab FX2N (FXN) to afford the tracer in modest radiochemical yields (RCY) of 18-25%, it is unsuitable for cassette-based systems with a single reactor. To simplify implementation on an automated synthesis module, the radiosynthesis of [F]JK-PSMA-7 was devised as a one-pot, two-step reaction.
View Article and Find Full Text PDFJ Clin Med
January 2025
Department of Oral and Maxillofacial Surgery, University Hospital of Salzburg, Paracelsus Medical University, 5020 Salzburg, Austria.
: Defects in maxillary and mandibular continuity are common in maxillofacial practice. They can occur after trauma, osteonecrosis, congenital jaw deformities, or surgical resection of benign or malignant tumours. Reconstruction with microvascular bone flaps and subsequent prosthetic rehabilitation is considered the contemporary first line treatment.
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