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Lay Summary Glioblastoma is an aggressive brain cancer, and it can be difficult to tell whether changes seen on scans after radiation treatment represent tumor growth or treatment-related effects. The authors of this study wanted to evaluate whether a specialized imaging test called PSMA PET could help define tumor boundaries for radiation planning and distinguish tumor progression from treatment-related changes. To do this, they performed PSMA PET scans in 27 patients with high-grade gliomas, including patients undergoing radiation planning and patients being evaluated for possible tumor recurrence. They found that tumors showed higher PSMA PET signal than surrounding tissue, that PSMA PET sometimes identified tumor beyond what was visible on standard MRI, and that it correctly distinguished tumor progression from treatment-related changes in most patients.

Abstract BACKGROUND [177Lu]Lu-PSMA-617 improves survival and quality of life in men with metastatic castration-resistant prostate cancer but requires substantial healthcare involvement. Our analysis evaluated the time toxicity associated with [177Lu]Lu-PSMA-617, representing the first dedicated radioligand time toxicity assessment. MATERIALS AND METHODS We conducted a multi-institutional retrospective study of patients initiating [177Lu]Lu-PSMA-617 between April 2022 and March 2023. Patients were followed from first [177Lu]Lu-PSMA-617 administration until 3 months after the final cycle, initiation of new systemic therapy, or death. Time toxicity was quantified as healthcare contact days during the at-risk interval. Associations with baseline characteristics were evaluated using negative binomial regression models. Univariate and multivariable models were performed. RESULTS Among 135 patients, median age was 69 years and median prior systemic therapies was 4. Patients completed a median of 5 [177Lu]Lu-PSMA-617 cycles over 7.6 months. Median healthcare contact days were 20 (IQR, 15–28), representing 9.5% (IQR, 6.4–13.9) of at-risk days. Fifteen patients (11%) experienced high time toxicity (>1 contact day per 5 days), while 42 (31%) had low time toxicity (≤1 contact day per 14 days). Among the 57 patients who received both cycle 1 and cycle 6, mean per cycle healthcare contact days were 4 and 3.6, respectively (paired Wilcoxon signed-rank test, p = 0.04). Routine oncology visits comprised 32.7% of contact days, compared with 8.8% from hospitalizations. Lower baseline hemoglobin was independently associated with greater time toxicity (RR = 0.87; 95% CI, 0.79–0.96; p = 0.004). CONCLUSION In heavily pretreated patients, [177Lu]Lu-PSMA-617 demonstrated relatively low time toxicity, supporting it as a time-efficient therapy.

Background: Staphylococcus aureus causes bloodstream and skin infections in humans. The prevalence of multidrug-resistant S. aureus strains means new antibiotics are needed. A novel antimicrobial drug named SK-03-92, a synthetic aromatic organic stilbenoid compound, kills S. aureus cells within 30 min, but an increase in both biofilm formation and persister cells occurs. SK-03-92 treatment downregulates transcription of the biofilm regulating protein regulator (brpR) gene and biofilm regulating protein sensor (brpS) gene in S. aureus. BrpR/BrpS system may be a LytTR regulatory system tied to biofilm formation, creation of persister cells, and late-stage competence in S. aureus. The aim of this study was to determine what biofilm, late-stage competence, and persister-associated genes were regulated in a brpR mutant compared to wild-type strains. Methods: In this study, involvement of BrpR in regulating other genes was assessed by comparing transcriptional changes in a brpR mutant strain to the S. aureus parent strain via RNA sequencing (RNA-Seq). Bioinformatic analysis was then performed on the RNA-Seq data to assess what biochemical pathways might be involved. Results: From these analyses, 440 genes were identified that had significant differences in transcript abundance when comparing the brpR mutant to wild-type strains. Quantitative reverse transcription polymerase chain reaction analysis confirmed bacA, icd, metE, and pdhA transcript levels were lower, whereas alr and mraY were higher in the brpR mutant versus wild-type strain. Furthermore, an enzymatic assay targeting NADH production from the pyruvate dehydrogenase complex showed lower levels in the mutant compared to wild-type strain. Conclusions: Overall, the study demonstrated several biosynthetic pathways tied to biofilm formation and late-stage competency may be regulated by BrpR and some potential leads for the mechanism of action of the SK-03-92 drug were uncovered.

Abstract Medical education transmits more than formal knowledge; it signals what matters through formal, informal, and hidden curricula. Drawing on Schein’s theory of organizational culture, this commentary synthesizes insights from three 2026 Research in Medical Education (RIME) studies to examine how artifacts, values, and underlying assumptions shape learning environments. The reviewed studies—on multimorbidity in undergraduate medical education, ritualized group handoff in residency, and learner recovery from failure—illustrate how educational practices encode organizational priorities in distinct ways. In curricular structures, multimorbidity is often marginalized or abstracted, signaling the privileging of specialized over integrative, generalist care. In clinical routines, ritualized handoffs align shared values with practices while simultaneously reinforcing hierarchical assumptions. In learner–teacher interactions, responses to failure communicate whether growth and psychological safety are genuinely supported. Together, these studies highlight three mechanisms through which the hidden curriculum operates: invisibly through structural design, explicitly through tightly aligned rituals, and relationally through interpersonal enactment. Highlighting these mechanisms, this research underscores the need for deliberate alignment between educational artifacts and espoused values. Ongoing attention to these signals is essential to cultivating organizational cultures that prepare physicians to navigate complexity, engage meaningfully in practice, and develop resilient professional identities.

Purpose: To measure the computed tomography (CT) attenuation of acute pulmonary embolism (PE) and establish an upper Hounsfield unit (HU) threshold above which it is unlikely to occur. Materials and Methods: This retrospective study analyzed CT pulmonary angiography (CTPA) exams in patients with acute PE (2018–2023) who had a prior negative CTPA in the preceding 2 weeks. Clot and artifact attenuation were measured on the positive and prior negative CTPA respectively. Analysis of variance with post hoc tests and linear regression analysis were performed to determine the effects of technical and other parameters on clot and artifact attenuation. Results: A total of 60 patients were included, each with 1 record or a pair of CTPA exams, yielding 105 clots and 41 artifacts. Mean attenuation for acute PE was 50±40 HU, and for artifact was 110±146 HU. A threshold of 125 HU achieved 97% (102/105) sensitivity for acute PE below it and the same specificity for artifact above it. Specificity for acute PE below this threshold was 37% (15/41). Subsegmental clots had a lower attenuation than all other clots as a group. Kilovoltage peak (kVp) and proximal vessel attenuation were poor predictors of clot attenuation . Conclusions: Most acute PE demonstrated a CT attenuation ≤125 HU on standard CTPA, an upper threshold higher than previously reported, while artifacts demonstrated both lower and higher attenuation. An attenuation >125 HU on standard CTPA, favoring artifact rather than acute PE, may be a useful adjunct to morphologic differentiation between these entities.

Background and Purpose Stroke is a frequent manifestation of non-bacterial thrombotic endocarditis (NBTE), yet current knowledge largely stems from case reports and small case series. This systematic review summarizes stroke presentation, imaging features, management, and outcomes in patients with NBTE-related stroke. Methods We conducted a patient-level systematic review of published case reports and case series. PubMed, MEDLINE, Embase, Web of Science, and PsycINFO were searched from inception through August 2025 for studies reporting individual patients with NBTE-related stroke. Extracted data included demographics, vascular risk factors, stroke presentation, imaging features, NBTE etiology, treatment (unfractionated heparin/low-molecular-weight heparin [UFH/LMWH], vitamin K antagonists [VKA], direct oral anticoagulants [DOACs], and/or valvular surgery), and outcomes. Multivariable regression was used to explore factors associated with recurrent stroke and mortality. Results We included 236 patients with NBTE and stroke from 218 studies (median age 56 years [IQR: 43–63], 63% female). Left hemispheric stroke syndromes predominated among clinical presentations (27%), and multi-vessel territory ischemic infarcts (>2 territories) were observed in 65%. Conventional vascular risk factors were infrequent (0%−21%), whereas deep vein thrombosis (43%) and systemic embolism (41%) frequently preceded or coincided with stroke onset. Malignancy (70%) and autoimmune disease (25%) were the main NBTE etiologies. Anticoagulation was initiated in 70%, and 21% underwent valvular surgery. Over a median follow-up of 2.0 months, stroke recurred in 43% and death occurred in 49% of patients. Malignant etiology (aOR 10.3, P < 0.001) and metastases (aOR 3.9, P < 0.001) were associated with increased mortality, while VKA use (aOR 0.08, P < 0.001) and autoimmune etiology (aOR 0.1, P < 0.001) were associated with lower mortality. Malignancy (aOR 2.8, P < 0.001) and DOAC use (aOR 5.2, P = 0.012) were associated with increased risk of recurrent stroke. Conclusion NBTE should be considered in stroke patients lacking conventional vascular risk factors, particularly those with malignancy or autoimmune disease. Malignancy and DOAC use were associated with higher recurrent stroke risk, while VKA use was associated with lower mortality; however, these anticoagulant-class findings should be considered hypothesis-generating and interpreted cautiously given the case-report evidence base, small treatment subgroups, potential confounding, and limited follow-up. What this study adds By synthesizing patient-level data from published case reports and case series, this review provides a stroke-focused characterization of NBTE, including clinical presentation, infarct topography, underlying etiologies, management strategies, recurrent cerebrovascular events, and mortality. The findings highlight multifocal infarction, malignancy-associated NBTE, and recurrent stroke despite anticoagulation as key clinical concerns, while emphasizing that observed associations with anticoagulant class should be viewed as hypothesis-generating rather than definitive treatment guidance

Background TP53 mutational status ( TP53 ms) is prognostically important in myeloid neoplasms. Immunohistochemistry (IHC) of p53 has been used as a surrogate for TP53 mutations, with faster results than next-generation sequencing (NGS) and cytogenetic analysis. Given the challenges posed by heterogeneous p53 IHC expression, this study aims to evaluate the interobserver interpretation of p53 stain as a surrogate marker for TP53m . Methods Fifty-three bone marrow (BM) specimens previously diagnosed as myeloid neoplasms or nonneoplastic BM specimens with available concurrent TP53ms were evaluated. p53 IHC staining was performed on all 53 core biopsy or clot sections. TP53 mutation was found in 24 cases ( TP53 m). Twenty-nine specimens were TP53 wild-type and served as the control group. Six hematopathologists (HPs) blinded to the diagnosis and TP53 m independently scored the p53 staining pattern of the biopsies/clot sections for overall staining percentage (OSP) and staining intensity (dark staining percentage as a percentage of total cells (DCP)). Results The intraclass correlation was excellent for OSP (0.927) and good for DCP (0.848). For OSP, a cutoff of 30% resulted in sensitivity of 83.3%, specificity of 89.7%, PPV of 87.0%, and NPV of 86.7%. For DCP, a cutoff of 10% achieved sensitivity of 87.5%, specificity of 96.6%, PPV of 95.4%, and NPV of 90.3%. Additionally, DCP significantly correlated with the VAF of TP53 m (R = 0.469, p = 0.028). Conclusion High inter-rater reliability for OSP and DCP supports integrating p53 IHC into bone marrow evaluations for rapid TP53 m assessment. With superior specificity and predictive values, DCP proves to be a more reliable diagnostic marker for TP53 mutations. While this approach shows promise for myeloid neoplasms, further validation is needed to overcome challenges and expand its clinical utility for tailored treatment strategies.