Computationally efficient collimator-detector response compensation in high energy SPECT using 1D convolutions and rotations.

. Modeling of the collimator-detector response (CDR) in single photon emission computed tomography (SPECT) reconstruction enables improved resolution and accuracy, and is thus important for quantitative imaging applications such as dosimetry. The implementation of CDR modeling, however, can become a computational bottleneck when there are substantial components of septal penetration and scatter in the acquired data, since a direct convolution-based approach requires large 2D kernels.

Physical and Surface Chemical Analysis of High-Quality Antimicrobial Cotton Fabrics Functionalized with CuO Grown from Different Copper Salts: Experimental and Theoretical Approach.

The emergence of harmful microorganisms poses a public health challenge. Antimicrobial cotton textiles with semiconductor oxides offer a promising solution to mitigate pathogen spread. Here, we study the physicochemical interactions between copper oxides (CuO) and cellulose in cotton fiber functionalized with these same oxides for antimicrobial properties.

Impact of diabetes on epicardial reperfusion and mortality in a contemporary STEMI population undergoing mechanical reperfusion: Insights from the ISACS STEMI COVID 19 registry.

Background And Aim: Diabetes has been shown in last decades to be associated with a significantly higher mortality among patients with ST-segment elevation myocardial infarction (STEMI) treated with primary PCI (PPCI). Therefore, the aim of current study was to evaluate the impact of diabetes on times delays, reperfusion and mortality in a contemporary STEMI population undergoing PPCI, including treatment during the COVID pandemic.

Methods And Results: The ISACS-STEMI COVID-19 is a large-scale retrospective multicenter registry involving PPCI centers from Europe, Latin America, South-East Asia and North-Africa, including patients treated from 1st of March until June 30, 2019 and 2020.

Impact of cell geometry, cellular uptake region, and tumour morphology on Ac and Lu dose distributions in prostate cancer.

Background: Radiopharmaceutical therapy with Ac- and Lu-PSMA has shown promising results for the treatment of prostate cancer. However, the distinct physical properties of alpha and beta radiation elicit varying cellular responses, which could be influenced by factors such as tumour morphology. In this study, we use simulations to examine how cell geometry, region of pharmaceutical uptake within the cell to model different internalization fractions, and the presence of tumour hypoxia and necrosis impact nucleus absorbed doses and dose heterogeneity with Ac and Lu.

Synthesis and Evaluation of Ga- and Lu-Labeled [Pro]bombesin(8-14) Derivatives for Detection and Radioligand Therapy of Gastrin-Releasing Peptide Receptor-Expressing Cancer.

The gastrin-releasing peptide receptor (GRPR) is overexpressed in a variety of cancers and represents a promising target for diagnosis and therapy. However, the extremely high accumulation in the pancreas observed for most of the clinically evaluated GRPR-targeted radiopharmaceuticals could limit their applications. In this study, we synthesized one GRPR antagonist (ProBOMB5) and two GRPR agonists (LW02056 and LW02057) by replacing the 4-thiazolidinecarboxylic acid (Thz) residue in our previously reported GRPR-targeted tracers with Pro.

Impact of hypertension on mortality in patients with ST-elevation myocardial infarction undergoing primary angioplasty: insights from the international multicenter ISACS-STEMI registry.

Background: Hypertension is the most prevalent cardiovascular risk factor, with several detrimental effects on the cardiovascular system. Contrasting results have been reported so far on its prognostic role in patients admitted for ST-segment elevation myocardial infarction (STEMI). Therefore, we investigated the impact of hypertension on short-term mortality in a large multicenter contemporary registry of STEMI patients, including patients treated during COVID-19 pandemic.

Preclinical Evaluation of Ac as a Theranostic Agent: Imaging, Dosimetry, and Therapy.

Ac (t = 29.37 h) has been proposed as a theranostic radioisotope leveraging both its diagnostic γ-emissions and therapeutic α-emissions. Ac emits 158 and 230 keV γ-photons ideal for quantitative SPECT imaging and acts as an in vivo generator of 4 high-energy α-particles.

Quantitative SPECT imaging of Tb and Tb for preclinical theranostic radiopharmaceutical development.

Background: Element-equivalent matched theranostic pairs facilitate quantitative in vivo imaging to establish pharmacokinetics and dosimetry estimates in the development of preclinical radiopharmaceuticals. Terbium radionuclides have significant potential as matched theranostic pairs for multipurpose applications in nuclear medicine. In particular, Tb (t = 5.

Evolution of ion channels in cetaceans: a natural experiment in the tree of life.

Cetaceans represent a natural experiment within the tree of life in which a lineage changed from terrestrial to aquatic habitats. This shift involved phenotypic modifications, representing an opportunity to explore the genetic bases of phenotypic diversity. Among the different molecular systems that maintain cellular homeostasis, ion channels are crucial for the proper physiological functioning of all living species.

An International Study of Factors Affecting Variability of Dosimetry Calculations, Part 3: Contribution from Calculating Absorbed Dose from Time-Integrated Activity.

Image-based dosimetry-guided radiopharmaceutical therapy has the potential to personalize treatment by limiting toxicity to organs at risk and maximizing the therapeutic effect. The Lu dosimetry challenge of the Society of Nuclear Medicine and Molecular Imaging consisted of 5 tasks assessing the variability in the dosimetry workflow. The fifth task investigated the variability associated with the last step, dose conversion, of the dosimetry workflow on which this study is based.

Theranostic digital twins: Concept, framework and roadmap towards personalized radiopharmaceutical therapies.

Radiopharmaceutical therapy (RPT) is a rapidly developing field of nuclear medicine, with several RPTs already well established in the treatment of several different types of cancers. However, the current approaches to RPTs often follow a somewhat inflexible "one size fits all" paradigm, where patients are administered the same amount of radioactivity per cycle regardless of their individual characteristics and features. This approach fails to consider inter-patient variations in radiopharmacokinetics, radiation biology, and immunological factors, which can significantly impact treatment outcomes.

quantitative SPECT imaging of actinium-226: feasibility and proof-of-concept.

.Ac radiopharmaceuticals have tremendous potential for targeted alpha therapy, however,Ac (= 9.9 d) lacks direct gamma emissions forimaging.

DosePatch: physics-inspired cropping layout for patch-based Monte Carlo simulations to provide fast and accurate internal dosimetry.

Background: Dosimetry-based personalized therapy was shown to have clinical benefits e.g. in liver selective internal radiation therapy (SIRT).

Lessons learned from a multi-data source research collaboration: The mirabegron post-authorization safety study program.

Background: Many factors contribute to developing and conducting a successful multi-data source, non-interventional, post-authorization safety study (NI-PASS) for submission to multiple health authorities. Such studies are often large undertakings; evaluating and sharing lessons learned can provide useful insights to others considering similar studies.

Objectives: We discuss challenges and key methodological and organizational factors that led to the delivery of a successful post-marketing requirement (PMR)/PASS program investigating the risk of cardiovascular and cancer events among users of mirabegron, an oral medication for the treatment of overactive bladder.

Heterogeneous PSMA ligand uptake inside parotid glands.

Unlabelled: The purpose of this investigation is to quantify the spatial heterogeneity of prostate-specific membrane antigen (PSMA) positron emission tomography (PET) uptake within parotid glands. We aim to quantify patterns in well-defined regions to facilitate further investigations. Furthermore, we investigate whether uptake is correlated with computed tomography (CT) texture features.

Evaluating Outcome Prediction via Baseline, End-of-Treatment, and Delta Radiomics on PET-CT Images of Primary Mediastinal Large B-Cell Lymphoma.

Objectives: Accurate outcome prediction is important for making informed clinical decisions in cancer treatment. In this study, we assessed the feasibility of using changes in radiomic features over time (Delta radiomics: absolute and relative) following chemotherapy, to predict relapse/progression and time to progression (TTP) of primary mediastinal large B-cell lymphoma (PMBCL) patients.

Material And Methods: Given the lack of standard staging PET scans until 2011, only 31 out of 103 PMBCL patients in our retrospective study had both pre-treatment and end-of-treatment (EoT) scans.

A multi-site study on sex differences in cortical thickness in non-demented Parkinson's disease.

Clinical, cognitive, and atrophy characteristics depending on sex have been previously reported in Parkinson's disease (PD). However, though sex differences in cortical gray matter measures in early drug naïve patients have been described, little is known about differences in cortical thickness (CTh) as the disease advances. Our multi-site sample comprised 211 non-demented PD patients (64.

Neural blind deconvolution for deblurring and supersampling PSMA PET.

. To simultaneously deblur and supersample prostate specific membrane antigen (PSMA) positron emission tomography (PET) images using neural blind deconvolution..

Semi-supervised learning towards automated segmentation of PET images with limited annotations: application to lymphoma patients.

Manual segmentation poses a time-consuming challenge for disease quantification, therapy evaluation, treatment planning, and outcome prediction. Convolutional neural networks (CNNs) hold promise in accurately identifying tumor locations and boundaries in PET scans. However, a major hurdle is the extensive amount of supervised and annotated data necessary for training.

Cortical Macro- and Microstructural Changes in Parkinson's Disease with Probable Rapid Eye Movement Sleep Behavior Disorder.

Background: Evidence regarding cortical atrophy patterns in Parkinson's disease (PD) with probable rapid eye movement sleep behavior disorder (RBD) (PD-pRBD) remains scarce. Cortical mean diffusivity (cMD), as a novel imaging biomarker highly sensitive to detecting cortical microstructural changes in different neurodegenerative diseases, has not been investigated in PD-pRBD yet.

Objectives: The aim was to investigate cMD as a sensitive measure to identify subtle cortical microstructural changes in PD-pRBD and its relationship with cortical thickness (CTh).

Exploration of commercial cyclen-based chelators for mercury-197 m/g incorporation into theranostic radiopharmaceuticals.

A comprehensive investigation of the Hg coordination chemistry and Hg radiolabeling capabilities of cyclen-based commercial chelators, namely, DOTA and DOTAM (aka TCMC), along with their bifunctional counterparts, -SCN-Bn-DOTA and -SCN-Bn-TCMC, was conducted to assess the suitability of these frameworks as bifunctional chelators for the Hg theranostic pair. Radiolabeling studies revealed that TCMC and DOTA exhibited low radiochemical yields (0%-6%), even when subjected to harsh conditions (80°C) and high ligand concentrations (10 M). In contrast, -SCN-Bn-TCMC and -SCN-Bn-DOTA demonstrated significantly higher Hg radiochemical yields (100% ± 0.