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• Pub. Date : 2025
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Abstract Purpose The positron range effect can impair PET image quality of Gallium-68 (68Ga). A positron range correction (PRC) can be applied to reduce this effect. In this study, the effect of a tissue-independent PRC for 68Ga was investigated on patient data. Methods PET/CT data (40 patients: [68Ga]Ga-DOTATOC or [68Ga]Ga-PSMA) were reconstructed using Q.Clear reconstruction algorithm. Two reconstructions were performed per patient, Q.Clear with and without PRC. SUVmax and contrast-to-noise ratio (CNR) values per lesion were compared between PRC and non-PRC images. Five experienced nuclear medicine physicians reviewed the images and chose the preferred reconstruction based on the image quality, lesion detectability, and diagnostic confidence. Results A total of 155 lesions were identified. The PRC resulted in statistically significant increase of the SUVmax and CNR for soft tissue lesions (6.4%, p < 0.001; 8.6%, p < 0.001), bone lesions (14.6%, p < 0.001; 12.5%, p < 0.001), and lung lesions (3.6%, p = 0.010; 6.3%, p = 0.001). This effect was most prominent in small lesions (SUVmax: 12.0%, p < 0.001, and CNR: 13.0%, p < 0.001). Similar or better image quality, lesion detectability, and diagnostic confidence was achieved in PRC images compared to the non-PRC images as those assessed by the expert readers. Conclusions A tissue-independent PRC increased the SUVmax and CNR in soft tissue, bone, and lung lesions with a larger effect for the small lesions. Visual assessment demonstrated similar or better image quality, lesion detectability, and diagnostic confidence in PRC images compared to the non-PRC images.

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• Pub. Date : 2025
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Photoreceptor/retinal degeneration is the major cause of blindness. Induced and inherited mouse models of retinal degeneration are valuable tools for investigating disease mechanisms and developing therapeutic interventions. This study investigated the potential of the antioxidant resveratrol to relieve photoreceptor degeneration using mouse models. Clinical studies have shown a potential association between thyroid hormone (TH) signaling and age-related retinal degeneration. Excessive TH signaling induces oxidative stress/damage and photoreceptor death in mice. C57BL/6 (rod-dominant) and Nrl−/− (cone-dominant) mice at postnatal day 30 (P30) received triiodothyronine (T3) via drinking water (20 µg/mL) with or without concomitant treatment with resveratrol via drinking water (120 µg/mL) for 30 days, followed by evaluation of photoreceptor degeneration, oxidative damage, and retinal stress responses. In experiments using Leber congenital amaurosis model mice, mother Rpe65−/− and Rpe65−/−/Nrl−/− mice received resveratrol via drinking water (120 µg/mL) for 20 days and 10–13 days, respectively, beginning on the day when the pups were at P5, and pups were then evaluated for cone degeneration. Treatment with resveratrol significantly diminished the photoreceptor degeneration induced by T3 and preserved photoreceptors in Rpe65-deficient mice, manifested as preserved retinal morphology/outer nuclear layer thickness, increased cone density, reduced photoreceptor oxidative stress/damage and apoptosis, reduced upregulation of genes involved in cell death/inflammatory responses, and reduced macroglial cell activation. These findings demonstrate the role of oxidative stress in photoreceptor degeneration, associated with TH signaling and Rpe65 deficiency, and support the therapeutic potential of resveratrol/antioxidants in the management of retinal degeneration.

• Book : 14(2)
• Pub. Date : 2025
• Page : pp.154-154
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The present review highlights the role of computed tomography (CT), CT colonography (CTC), and magnetic resonance imaging (MRI) in the diagnosis, staging, response evaluation, and follow-up of colorectal cancer. For a CT scan, prior bowel preparation is required. This is done to enhance imaging of the colon with the use of oral or rectal contrast agents. Negative contrast like air or carbon dioxide are helpful in detecting polyps and masses by distending the colon. Virtual colonoscopy offers a lower-radiation alternative for polyp and cancer detection. Intravenous contrast administration with arterial and venous phase CT images is also important in complete staging of a known case of colon cancer and for evaluation of residual/recurrent disease. With respect to MRI, high-resolution T2-weighted images in multiple planes are important, with diffusion-weighted imaging (DWI) sequences being important for restaging. Intravenous contrast is not generally recommended. Contrast-enhanced CT and MRI are used for nodal and distant metastasis staging, with special attention to the pelvic side wall nodes. Positron emission tomography (PET) CT is to be considered for further evaluation if the findings are unclear and recurrence is suspected.

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• Pub. Date : 2025
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Abstract Positron emission tomography (PET) imaging plays a pivotal role in oncology for the early detection of metastatic tumors and response to therapy assessment due to its high sensitivity compared to anatomical imaging modalities. The balance between image quality and radiation exposure is critical, as reducing the administered dose results in a lower signal-to-noise ratio (SNR) and information loss, which may significantly affect clinical diagnosis. Deep learning (DL) algorithms have recently made significant progress in low-dose (LD) PET reconstruction. Nevertheless, a successful clinical application requires a thorough evaluation of uncertainty to ensure informed clinical judgment. We propose NPB-LDPET, a DL-based non-parametric Bayesian framework for LD PET reconstruction and uncertainty assessment. Our framework utilizes an Adam optimizer with stochastic gradient Langevin dynamics (SGLD) to sample from the underlying posterior distribution. We employed the Ultra-low-dose PET Challenge dataset to assess our framework’s performance relative to the Monte Carlo dropout benchmark. We evaluated global reconstruction accuracy utilizing SSIM, PSNR, and NRMSE, local lesion conspicuity using mean absolute error (MAE) and local contrast, and the clinical relevance of uncertainty maps employing correlation between the uncertainty measures and the dose reduction factor (DRF). Our NPB-LDPET reconstruction method exhibits a significantly superior global reconstruction accuracy for various DRFs (paired t-test, $$p<0.0001$$ p < 0.0001 , N=10, 631). Moreover, we demonstrate a 21% reduction in MAE (573.54 vs. 723.70, paired t-test, $$p<0.0001$$ p < 0.0001 , N=28) and an 8.3% improvement in local lesion contrast (2.077 vs. 1.916, paired t-test, $$p<0.0001$$ p < 0.0001 , N=28). Furthermore, our framework exhibits a stronger correlation between the predicted uncertainty 95th percentile score and the DRF ( $$r^2=0.9174$$ r 2 = 0.9174 vs. $$r^2=0.6144$$ r 2 = 0.6144 , N=10, 631). The proposed framework has the potential to improve clinical decision-making for LD PET imaging by providing a more accurate and informative reconstruction while reducing radiation exposure. Graphical abstract

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• Pub. Date : 2025
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Background: Traditional freehand techniques in high tibial osteotomy (HTO) have been shown to lack precision and accuracy. Patient-specific instrumentation (PSI) and fixation created from cross-sectional imaging have recently been introduced to address this problem. Purpose/Hypothesis: The purpose of the study was to compare traditional freehand techniques versus PSI in a human cadaveric model of HTO. It was hypothesized that the osteotomies performed using PSI would require less radiation exposure for operating room staff and would reduce deviation from the planned correction in the coronal, sagittal, and axial planes. Study Design: Controlled laboratory study. Methods: Sixteen matched cadaveric knees underwent medial opening-wedge HTO via the freehand method (n = 8) or PSI technique (n = 8) with a predetermined planned opening-wedge size. Computed tomography was used to measure the achieved wedge size as well as alignment parameters in the coronal, sagittal, and axial planes. Radiation dose, number of fluoroscopic images taken, and total operative time were recorded. Results: The mean deviation from the planned wedge size was smaller in the PSI group compared with the freehand group (0.505 vs 3.016 mm, respectively; P < .01). Total radiation dose to medical staff (0.85 vs 2.04 mGy; P < .01) and number of fluoroscopic images (15.5 vs 41; P < .01) were also smaller in the PSI versus the freehand group, respectively. No difference was seen in total operative time between the 2 groups ( P = .62). Conclusion: In cadaveric specimens, the PSI technique demonstrated superior accuracy and decreased radiation exposure for medical staff compared with the traditional freehand technique without compromising operative efficiency. Clinical Relevance: The use of PSI when HTO is performed can lead to more accurate operations and potentially improve outcomes.

• Book : 13(1)
• Pub. Date : 2025
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Abstract We investigate the relative yields of various like and unlike mass hadrons in ultra-relativistic heavy-ion collisions (URHIC). In the framework of thermal model a strong evidence of strangeness imbalance is observed in the experiments at lower collision energies relative to non-strange particles, particularly pions. The study indicates that like mass particle ratios in the system at the chemical freeze-out in URHIC can be described effectively by considering baryons (antibaryons) as point like as well as finite size particles which imitates hard-core repulsive interactions leading to an excluded volume type effect. In this analysis, we employ the statistical Hadron Resonance Gas (HRG) model for both cases. A comparison between the two cases is provided. However, the importance of considering baryons (antibaryons) as finite size particles is revealed in the description of baryon to meson ratios. Best fits to particle ratios are obtained using $\chi^{2}$-minimization procedure. For the case of finite-size baryons (antibaryons), we find that considering their hard-core radii allows us to fit the available antibaryon-to-baryon and baryon (antibaryon)-to-pion ratio experimental data simultaneously quite well with the same model parameter values. Moreover, our results align well with the proton radius puzzle observed in the muonic hydrogen measurement data. Furthermore, the study reveals two distinct chemical freeze-out stages in both cases, where the earlier one corresponds to baryonic (hyperonic) and antibaryonic (antihyperonic) states and a later one to mesonic degrees of freedom. A comparison of freeze-out lines obtained from both the cases is made along with the results of some earlier studies.

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• Pub. Date : 2025
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ABSTRACTTumor necrosis factor receptor‐associated factor‐6 (TRAF6) is a well‐established upstream regulator of the IKK complex, essential for the modulation of the NF‐κB (nuclear factor kappa B) signaling pathway. Aberrant activation of TRAF6 has been strongly implicated in the pathogenesis of various cancers, including hepatocellular carcinoma (HCC). The speckle type BTB/POZ protein (SPOP), an E3 ubiquitin ligase substrate‐binding adapter, constitutes a significant component of the CUL3/SPOP/RBX1 complex, which is closely linked to tumorigenesis. In this study, we demonstrated that the E3 ubiquitin ligase SPOP shielded TRAF6 from proteasomal degradation, leading to the hyperactivation of the NF‐κB pathway. Notably, a liver cancer‐associated S119N mutation in SPOP resulted in a failure to mediate the ubiquitination and subsequent degradation of TRAF6. Moreover, both gain‐of‐function and loss‐of‐function experiments revealed that SPOP inhibits the proliferation and invasion of HCC cells through the TRAF6‐NF‐κB axis in vitro and in vivo. Taken together, our findings elucidate the underpinning mechanism by which SPOP negatively regulates the stability of the TRAF6 oncoprotein, thus offering a new therapeutic target for HCC intervention.

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• Pub. Date : 2025
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Background: Radiation-associated angiosarcoma of the breast (RAASB) is a rare secondary angiosarcoma that typically develops subsequent to breast-conserving therapy for breast cancer. The parameters of the resection width and depth remain the subject of considerable controversy. More recent data indicate that radical resection of the complete radiation field at the thorax is associated with improved local control and survival. Objectives: The present study investigates the radical resection technique of the entire radiation field and subsequent defect coverage in RAASB, as well as the medium-term follow-up. Design: Monocentric, retrospective, and non-comparative study. Methods: From January 2017 to January 2024 a total of 10 patients with RAASB were treated at our hospital. The radical resection technique was employed in the treatment of all patients, encompassing the entire radiation field. Three patients received local flaps (two of whom received vertical and transversal rectus abdominis muscle flaps and one received a local random pattern flap), while the remaining seven were treated with split-thickness skin grafts for defect coverage. Results: The median age at initial diagnosis of breast cancer was 59.3 ± 9.41 years, while that of RAASB was 66.2 ± 8.32 years. The median latency period between the start of irradiation of the chest wall and the initial presentation of RAASB was 6.5 ± 3.08 years. The cumulative median total radiation dose was 57.23 ± 8.34 Gray (cumulative Gray) in 9 of the 10 patients. The overall survival (OS) was 80% in the cohort, with a median follow-up period of 40.0 ± 27.96 months. Three patients exhibited local relapses following radical resection, with two of these patients ultimately succumbing to their condition. Conclusion: Patients with RAASB may benefit from a radical resection of the entire radiation field. Despite the relatively mutilating nature of the procedure, the radical resection technique may have the potential to reduce the rate of local recurrence and prolong OS.

• Book : 17()
• Pub. Date : 2025
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• Pub. Date : 2025
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