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Background: Long‐distance running is a common cause of Achilles tendinopathy. A reliable magnetic resonance imaging (MRI) technique to track early changes in the tendon caused by running could facilitate more effective interventions to combat progression. Purpose: To evaluate an ultrashort echo time sequence with magnetization transfer preparation (UTE‐MT) in the detection of changes in Achilles tendons of amateur marathon runners before and after long‐distance running. Study Type: Prospective. Population: Thirty‐two runners (19 enrolled for full marathons and 13 enrolled for half‐marathons) and 5 healthy non‐runners. Field Strength/Sequence: 3.0 T; UTE‐MT and dual‐echo UTE for T2* assessment (UTE‐T2*). Assessment: MRI was performed 1‐week pre‐race, 2‐days post‐race, and 4‐weeks post‐race. UTE‐MT ratio (UTE‐MTR) and UTE‐T2* of tendon were measured by two independent radiologists who were blinded to the scan time point and participant data. The Achilles tendon was divided into six regions of interest (ROIs) for data analysis, namely the insertion part (INS), middle part (MID), muscle‐tendon junction (MTJ), tendon‐bone insertion (TBI), tendon‐muscle insertion (TMI), and whole tendon (bulk). Statistical Tests: Analysis of variance and Friedman's rank tests were used to evaluate changes in UTE‐MTR and UTE‐T2* between time points. Tukey test and Bonferroni method were used for further comparisons. P < 0.05 was considered significant. Results: The UTE‐MTR values of most tendon ROIs changed significantly between the measured time points, except for the INS region (P = 0.1977). Conversely, the UTE‐T2* values only showed significant changes in the MID and TBI regions. Paired comparisons showed that the UTE‐MTR decreases in the MTJ, MID, TMI, and bulk regions at 2‐days post‐race were significant compared to measures taken pre‐race and 4‐weeks post‐race. For UTE‐T2* measurements, significant differences were observed only for the MID region between pre‐race and 2‐days post‐race (P = 0.0408, 95% CI: 0.0061, 0.1973), and for the TBI region between pre‐race and 4‐weeks post‐race (P = 0.0473, 95% CI: 0.0013, 0.1766). Data Conclusion: The UTE‐MT sequence is able to detect biochemical changes in the Achilles tendon after long‐distance running. Level of Evidence: 2 Technical Efficacy: Stage 1 [ABSTRACT FROM AUTHOR]

This study was designed to investigate the protective effect of resveratrol (RES) on premature ovarian failure (POF) and the proliferation of female germline stem cells (FGSCs) at the tissue and cell levels. POF mice were lavaged with RES, and POF ovaries were co-cultured with RES and/or GANT61 in vitro. FGSCs were pretreated with Busulfan and RES and/or GANT61 and co-cultured with M1 macrophages, which were pretreated with RES. The weights of mice and their ovaries, as well as their follicle number, were measured. Ovarian function, antioxidative stress, inflammation, and FGSCs survival were evaluated. RES significantly increased the weights of POF mice and their ovaries as well as the number of follicles, while it decreased the atresia rate of follicles. Higher levels of Mvh, Oct4, SOD2, GPx, and CAT were detected after treatment with RES in vivo and in vitro. RES treatment resulted in significantly lower TNF-α and IL-6 concentrations and an obviously higher IL-10 concentration in the ovaries. In FGSCs, higher Mvh, Oct4, and SOD2 concentrations and lower TNF-α, IL-6, and MDA concentrations were measured in the RES group. Blockage of the Hh signaling pathway reversed the protective effect of RES on FGSCs. In conclusion, RES effectively improved the ovarian function of the POF model and the productive capacity of FGSCs via relieving oxidative stress and inflammation and a mechanism involving the Hh signaling pathway, suggesting that RES is a potential agent against POF and can aid in the survival of FGSCs. [ABSTRACT FROM AUTHOR]

Achilles tendinopathy is often attributed to overuse, but its pathophysiology remains poorly understood. Disruption to the molecular structure of collagen is fundamental for the onset and progression of tendinopathy but has mostly been investigated in vitro. Here, we interrogated the in vivo molecular structure changes of collagen in rat Achilles tendons following treadmill running. Unexpectedly, the tendons' collagen molecules were not mechanically unfolded by running but denatured through proteolysis during physiological post-run remodeling. We further revealed that running induces inflammatory gene expressions in Achilles tendons and that long-term running causes prolonged, elevated collagen degradation, leading to the accumulation of denatured collagen and tendinopathy development. For applications, we demonstrated magnetic resonance imaging of collagenase-induced Achilles tendon injury in vivo using a denatured collagen targeting contrast agent. Our findings may help close the knowledge gaps in the mechanobiology and pathogenesis of Achilles tendinopathy and initiate new strategies for its imaging-based diagnosis.

Background: Knee osteoarthritis (OA) is harmful to people's health. Effective treatment depends on accurate diagnosis and grading. This study aimed to assess the performance of a deep learning (DL) algorithm based on plain radiographs in detecting knee OA and to investigate the effect of multiview images and prior knowledge on diagnostic performance., Methods: In total, 4,200 paired knee joint X-ray images from 1,846 patients (July 2017 to July 2020) were retrospectively analyzed. Kellgren-Lawrence (K-L) grading was used as the gold standard for knee OA evaluation by expert radiologists. The DL method was used to analyze the performance of anteroposterior and lateral plain radiographs combined with prior zonal segmentation to diagnose knee OA. Four groups of DL models were established according to whether they adopted multiview images and automatic zonal segmentation as the DL prior knowledge. Receiver operating curve analysis was used to assess the diagnostic performance of 4 different DL models., Results: The DL model with multiview images and prior knowledge obtained the best classification performance among the 4 DL models in the testing cohort, with a microaverage area under the receiver operating curve (AUC) and macroaverage AUC of 0.96 and 0.95, respectively. The overall accuracy of the DL model with multiview images and prior knowledge was 0.96 compared to 0.86 for an experienced radiologist. The combined use of anteroposterior and lateral images and prior zonal segmentation affected diagnostic performance., Conclusions: The DL model accurately detected and classified the K-L grading of knee OA. Additionally, multiview X-ray images and prior knowledge improved classification efficacy., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-22-1250/coif). BQ is an employee of Huiying Medical Technology Co. The other authors have no conflicts of interest to declare., (2023 Quantitative Imaging in Medicine and Surgery. All rights reserved.)