In MgF2:Mn2+, Eu2+ phosphors, the x-ray excited luminescence from Eu2+ is decreased while the emission from Mn2+ is increased in intensity with the increase of x-ray dose. In MgF2:Mn2+, the luminescence is also increased, and in MgF2:Eu2+, the emission of Eu2+ is also decreased in intensity with the increase of x-ray dose. However, the intensity changes with x-ray dose in the singly doped MgF2:Mn2+ and MgF2:Eu2+ phosphors are much less than those in the doubly doped MgF2:Mn2+, Eu2+ phosphors. The increase of Mn2+ emission in intensity is likely due to the breakdown of the forbidden transition by the defects created by x-ray irradiation. No conversion of Eu2+ ions to Eu3+ ions was observed in MgF2:Eu2+ phosphors during x-ray irradiation. The decrease of Eu2+ emission in intensity in MgF2:Mn2+, Eu2+ must be closely related to the interaction and the energy transfer to Mn2+ ions. The phenomenon observed is potentially interesting for the practical applications for radiation detection, as utilizing the ratio of the two emissions from Mn2+ and Eu2+ for radiation detection is more sensitive and more reliable than using emission intensity change only.

On March 23, 2022, the United States Food and Drug Administration (FDA) approved Pluvicto (lutetium Lu 177 vipivotide tetraxetan, also known as 177Lu-PSMA-617) for the treatment of adult patients with prostate-specific membrane antigen (PSMA)-positive metastatic castration-resistant prostate cancer (mCRPC) who have been treated with androgen receptor pathway inhibition and taxane-based chemotherapy. The recommended 177Lu-PSMA-617 dose is 7.4 gigabecquerels (GBq; 200 mCi) intravenously every 6 weeks for up to 6 doses, or until disease progression or unacceptable toxicity. The FDA granted traditional approval based on VISION (NCT03511664), which was a randomized (2:1), multicenter, open-label trial that assessed the efficacy and safety of 177Lu-PSMA-617 plus best standard of care (BSoC) (n=551) or BSoC alone (n=280) in men with progressive, PSMA-positive mCRPC. Patients were required to have received ≥1 androgen receptor pathway inhibitor, and 1 or 2 prior taxane-based chemotherapy regimens. There was a statistically significant and clinically meaningful improvement in overall survival (OS) with a median OS of 15.3 months in the 177Lu-PSMA-617 plus BSoC arm and 11.3 months in the BSoC arm, respectively (Hazard ratio: 0.62, 95% CI: 0.52, 0.74, p<0.001). The most common adverse reactions (≥20%) occurring at a higher incidence in patients receiving 177Lu-PSMA-617 were fatigue, dry mouth, nausea, anemia, decreased appetite, and constipation. The most common laboratory abnormalities that worsened from baseline in ≥30% of patients receiving 177Lu-PSMA-617 were decreased lymphocytes, decreased hemoglobin, decreased leukocytes, decreased platelets, decreased calcium, and decreased sodium. This article summarizes the FDA review of data supporting traditional approval of 177Lu-PSMA-617 for this indication.

In the photoluminescence (PL) of BaFBr:Eu2+,Eu3+, the emissions of Eu2+, carrier electron-hole (e-h) recombination, and Eu3+ are observed, while in the photostimulated luminescence (PSL) only the emission of Eu2+ is exhibited. This disappearance of e-h recombination in PSL is considered to be caused by carrier migration during photo-stimulation.

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Purpose Immune checkpoint inhibitors (ICIs) have shown durable responses in various malignancies. However, the response to ICI therapy is unpredictable, and investigation of predictive biomarkers needs to be improved. Experimental design In total, 120 patients receiving ICI therapy and 40 patients receiving non-ICI therapy were enrolled. Peripheral blood immune cell markers (PBIMs), as liquid biopsy biomarkers, were analyzed by flow cytometry before ICI therapy, and before the first evaluation. In the ICI cohort, patients were randomly divided into training (n = 91) and validation (n = 29) cohorts. Machine learning algorithms were applied to construct the prognostic and predictive immune-related models. Results Using the training cohort, a peripheral blood immune cell-based signature (BICS) based on four hub PBIMs was developed. In both the training and the validation cohorts, and the whole cohort, the BICS achieved a high accuracy for predicting overall survival (OS) benefit. The high-BICS group had significantly shorter progression-free survival and OS than the low-BICS group. The BICS demonstrated the predictive ability of patients to achieve durable clinical outcomes. By integrating these PBIMs, we further constructed and validated the support vector machine-recursive and feature elimination classifier model, which robustly predicts patients who will achieve optimal clinical benefit. Conclusions Dynamic PBIM-based monitoring as a noninvasive, cost-effective, highly specific and sensitive biomarker has broad potential for prognostic and predictive utility in patients receiving ICI therapy.

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After x-irradiation for 10 s, luminescence from BaFBr:Eu2+ phosphors by photostimulation of longer wavelength than F absorption bands was observed and assigned to the surface states or intrinsic defects of the powders. It is found that the luminescence by photostimulation into F bands can be reduced via electron migration from F centers into the surface states or intrinsic defects, thus reducing the x-ray storage or image stability. Surface passivation can lower these defects and improve the phosphors or imaging plate quality.