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The deposition of particulate matter in heat exchanger channels can greatly reduce their heat transfer efficiency, and a better understanding of the deposition characteristics of particulate matter in heat exchanger channels is essential for improving heat exchanger performance. The deposition characteristics of particles in a three-dimensional dimpled dimple channel were simulated using the Reynolds Stress Model (RSM) and Discrete Particle Model (DPM). The flow structure, secondary flow, temperature distribution and particle deposition distribution in the dimpled dimple channel were analyzed and investigated after mesh-independence testing and numerical validation. The results showed that the main mechanisms affecting the particle deposition characteristics in dimpled dimple channels were gravity, thermophoretic forces, turbulent flow structure, secondary flow and particle inertia, and the effects of these mechanisms change significantly with particle size. For small particles (dp≤10 μm), the presence of the dimpled dimple structure promoted deposition; however, for large particles (dp>10 μm), its presence had only a small effect on the distribution of particle deposition locations.

Objective To quantitatively measure the morphological parameters of femoral condyle based on MRI images so as to determine the effect of anterior-posterior femoral condyle geometry on patellar instability (PI) in patients with high-grade femoral trochlear dysplasia. Methods A total of 82 series of knee joint MRI images from 74 patients with high-grade femoral trochlear dysplasia who underwent MRI scanning in our hospital from January 2014 to January 2021 were retrospectively selected. According to the results of clinical diagnosis and radiological imaging, they were further divided into patellar dislocation group (n=45) and non-patellar dislocation group (n=37). Subsequently, the morphological parameters related to the femoral condyle of knee joint were measured quantitatively in the MRI images, including posterior condylar angle (PCA), width of medial-lateral epicondyle (MLW), medial posterior condyle width (MPCW), lateral posterior condyle width (LPCW), medial anterior condyle length (MACL), lateral anterior condyle length (LACL), medial posterior condyle length (MPCL), and lateral posterior condyle length (LPCL). Intraclass correlation coefficient (ICC) was used to assess the intra- and inter-observer reliability of the quantitative MRI measurements. Results The MPCW and LACL values were significantly lower in the patellar dislocation group than the non-patellar dislocation group (P < 0.05), whereas there were no statistical differences in PCA, MLW, LPCW, MACL, MPCL and LPCL values between the 2 groups. The measurement results of all parameters had good consistency within and among the observers (ICC≥0.80). Conclusion The patients of patellar dislocation have shorter lateral anterior femoral condyle and narrower medial posterior femoral condyle, which may be risk factors for dislocation in those with high-grade trochlear dysplasia.

Objectives: To evaluate the intima-media thickness (IMT) and elasticity of the carotid artery in non-obese polycystic ovary syndrome (PCOS) patients using a quantitative technique for vascular elasticity measurement and to explore the influencing factors. Methods: Sixty non-obese patients without metabolic and cardiovascular diseases who were diagnosed with PCOS in the Women and Children's Hospital of Chongqing Medical University from January to December 2022 were prospectively selected (case group), and 60 healthy volunteers matched for body mass index were included as the control group. Body weight, height, heart rate, blood pressure, and waist-to-hip ratio were recorded. Fasting blood samples were drawn from the elbow vein to measure hormone levels including total testosterone (TT), sex hormone-binding globulin (SHBG), fasting plasma glucose (FPG), fasting insulin (FINS), lipids, and homocysteine (Hcy). The insulin resistance index (HOMA-IR) and free androgen index (FAI) were calculated. Ultrasound elastography was used to measure the IMT and elastic function parameters of the right carotid artery, including vessel diameter, wall displacement, stiffness coefficient, and pulse wave velocity. Differences in various parameters between the two groups were analyzed, and correlations between the carotid stiffness coefficient and other serological indicators were assessed using Spearman correlation analysis. Results: No significant differences in age, body mass index, heart rate, systolic blood pressure, and diastolic blood pressure were observed between the two groups (all P>0.05), while the waist-to-hip ratio (WHR) was higher in the case group than in the control group (P<0.05).The hormone level serological indicators TT and FAI were higher in the case group than in the control group, and SHBG was lower in the case group than in the control group (all P<0.05). The metabolism-related serum indicators LDL-C, HDL-C, FPG, triglycerides, and total cholesterol levels were not statistically different between the two groups (all P>0.05), and serum FINS, HOMA-IR, and Hcy levels were significantly higher in the case group than in the control group (all P<0.05).No significant difference in carotid artery diameter was observed between the case group and control group (P>0.05). The carotid artery displacement in the case group was significantly smaller than that in the control group (P<0.05), and carotid IMT, hardness coefficient, and pulse wave propagation velocity were greater in the case group than in the control group (all P<0.05). The carotid elastic stiffness coefficient was positively correlated with WHR, TT, SHBG, FAI, FINS, HOMA-IR and Hcy to varying extents and negatively correlated with SHBG. Conclusion: In non-obese PCOS patients with no metabolic or cardiovascular disease, the carotid stiffness coefficient was increased and correlated with indicators of hyperandrogenism, insulin resistance, and hyperhomocysteinemia. [ABSTRACT FROM AUTHOR]

Background: Recent evidence suggests a crucial biological role for Circular RNAs (circRNAs) in keloid diseases, yet the underlying mechanisms remain unclear. This study explored the biological effects and molecular mechanisms of hsa_circ_0002198 in keloid formation. Methods: Real-time quantitative PCR (qRT-PCR) was employed to assess the expression of circ_0002198 in keloid tissues, normal skin tissues, keloid fibroblasts (KFs), and normal skin fibroblasts (NFs) from nine patients. To investigate the role of circ_0002198 in keloid pathogenesis, cell transfection technology was utilized to knock down circ_0002198. Various experiments including Cell Counting Kit-8 (CCK-8), 5-Ethynyl-2′-deoxyuridine (EdU), Transwell, wound healing assay, flow cytometry, and others were conducted to explore the potential mechanisms associated with circ_0002198 expression. The RNA-binding protein Eukaryotic translation initiation factor 4A, isoform 3 (EIF4A3) binding to circ_0002198 was identified and confirmed through bioinformatics databases prediction and RNA immunoprecipitation (RIP) assay. Finally, the expression of EIF4A3 was assessed, and both silencing and overexpression were employed to verify its role in circ_0002198 regulation. Results: The expression levels of circ_0002198 and EIF4A3 were notably elevated in keloid tissues and KFs compared to normal skin tissues and NFs. The reduction of circ_0002198 expression in KFs significantly impeded their proliferation, migration, and invasion. It also hindered the cell cycle process and the expression of associated proteins while concurrently promoting apoptosis in KFs. EIF4A3 was identified to bind to the flanks of circ_0002198, enhancing the occurrence of circ_0002198 and its role in regulating the progression of KFs. Conclusion: Our study offers insights into how Circular RNA may contribute to the pathogenesis of keloid formation, highlighting Circ_0002198 as a potential novel biomarker for keloids in association with EIF4A3. Further research, involving larger study cohorts, is necessary to broaden our understanding of keloid mechanisms and potential treatment approaches. [ABSTRACT FROM AUTHOR]

Objective To quantitatively measure and analyze the morphological features of posterior femoral condyle of anterolateral ligament (ALL) injury based on CT images. Methods A total of 41 knees with acute ALL injuries admitted in our hospital from January 2014 to April 2019 were retrospectively selected as the injury group, and the other 41 matched knee joints served as the control group. Their complete imaging data of the knee joints were collected, and the CT images were used to quantitatively measure the morphological parameters of knee joints in the 2 groups, including medial-lateral width of epicondyle (MLW), medial posterior condyle width (MPCW), and lateral posterior condyle width (LPCW), lateral condyle length (LCL), medial condyle length (MCL), lateral posterior condyle length (LPCL), medial posterior condyle length (MPCL), medial posterior condyle height (MPCH), and lateral posterior condyle height (LPCH). In addition, the ratios of posterior condyle widths (LPCW/MLW, MPCW/MLW) and those of lengths (LPCL/LCL, MPCL/MCL) was calculated to minimize individual differences. Statistical analysis was carried out for the differences of parameters between the 2 groups. Results The differences in width and length of posterior condyle between the 2 groups were statistically significant (P < 0.05). ① Width: MLW was greater (P=0.042), and the ratios of LPCW/MLW and MPCW/MLW were significantly lower in the ALL injury group than the control group (P < 0.05); ② Length: MCL, MPCL and LCL were larger (P < 0.05) and the ratio of LPCL/LCL was lower in ALL injury group than the control group (P < 0.01); ③ Height: There was no statistical difference in the height of medial and lateral posterior condyles between the 2 groups (P>0.05). Conclusion The medial posterior femoral condyle is narrower, and the lateral posterior femoral condyle is narrower and shorter. And shorter lateral posterior condyle increases the risk of ALL injury by changing the internal movement of knee joints.

Introduction Keloids are pathological scars that present great challenges for reconstructive surgery. The incidence of this disease is higher in non-Caucasians (Arnett and Bergman 1993). The pathogenesis of keloids is [...], MicroRNA-21 (miR-21) has been found to be upregulated in keloid tissue and to affect the proliferation and apoptosis of keloid fibroblasts; however, the possible mechanisms remain unclear. In this study, we aimed to evaluate the role of miR-21 in FasL-induced caspase-8 activation and the mitochondria-mediated apoptotic signaling pathway in keloid fibroblasts. Our study found that the protein level of FasL was decreased by miR-21 over-expression, while being enhanced by miR-21 inhibition in keloid fibroblasts. Subsequently, the mitochondria-mediated apoptosis of keloid fibroblasts was restrained by miR-21 overexpression, as evidenced by enhanced mitochondrial membrane potential and decreased production of mitochondrial ROS. Moreover, over-expression of miR-21 inhibited the activation of the caspase-8 and the mitochondria-mediated apoptotic signaling pathway. As expected, inhibition of miR-21 had the opposite effects. Finally, silencing of FasL suppressed miR-21 inhibition-induced apoptosis by inactivation of caspase-8 and the mitochondria-mediated apoptotic signaling pathway, which was comparable to Z-IETD-FMK, a caspase-8 inhibitor. Taken together, these results suggest that miR-21 regulates the apoptosis of keloid fibroblasts via targeting FasL, and caspase-8 and the mitochondria-mediated apoptotic signaling pathway is involved in this process. Our findings provide evidence that miR-21 may be considered to be a therapeutic target for keloids. Key words: miR-21, keloid, apoptosis, FasL, mitochondria-mediated apoptotic signaling pathway. Il s&apos;avere que miR-21 est regule a la hausse dans le tissu cheloidien et qu&apos;il affecte la proliferation et l&apos;apoptose des fibroblastes cheloidiens. Toutefois, les mecanismes sous-jacents eventuels demeurent flous. Dans cette etude, les auteurs visaient a evaluer le role de miR-21 dans l&apos;activation de la caspase-8 et la voie de signalisation mitochondriale de l&apos;apoptose induites par FasL dans les fibroblastes cheloidiens. Selon l&apos;etude actuelle, le niveau proteique de FasL etait diminue par la surexpression de miR-21, mais accru par l&apos;inhibition de miR-21 dans les fibroblastes cheloidiens. Subsequemment, la voie mitochondriale de l&apos;apoptose etait diminuee par la surexpression de miR-21 dans les fibroblastes cheloidiens, comme le demontrait l&apos;accroissement du potentiel membranaire mitochondrial et la diminution de la production de DRO mitochondriaux. De plus, la surexpression de miR-21 inhibait l&apos;activation de la caspase-8 et la voie de signalisation mitochondriale de l&apos;apoptose. Comme attendu, l&apos;inhibition de miR-21 avait l&apos;effet oppose. Finalement, le silencage de FasL supprimait l&apos;apoptose induite par l&apos;inhibition de miR-21 par l&apos;intermediaire de l&apos;inactivation de la caspase-8 et de la voie de signalisation mitochondriale de l&apos;apoptose, dans une mesure comparable au Z-IETD-FMK, un inhibiteur de la caspase-8. Dans l&apos;ensemble, cette etude suggere que miR-21 regule l&apos;apoptose des fibroblastes cheloidiens en ciblant FasL, et que la caspase-8 et la voie de signalisation mitochondriale de l&apos;apoptose sont impliques dans ce processus. Leurs resultats apportent un indice que miR-21 peut etre considere comme cible therapeutique des cheloides. [Traduit par la Redaction] Mots-cles : miR-21, cheloide, apoptose, FasL, voie de signalisation mitochondriale de l&apos;apoptose.

Purpose: Uterine fibroid is the most common benign tumor in female reproductive organs. In order to guide the treatment, it is crucial to detect the location, shape, and size of the tumor. This study proposed a deep learning approach based on attention mechanisms to segment uterine fibroids automatically on preoperative Magnetic Resonance (MR) images. Methods: The proposed method is based on U‐Net architecture and integrates two attention mechanisms: channel attention of squeeze‐and‐excitation (SE) blocks with residual connections, spatial attention of pyramid pooling module (PPM). We did the ablation study to verify the performance of these two attention mechanisms module and compared DARU‐Net with other deep learning methods. All experiments were performed on a clinical dataset consisting of 150 cases collected from our hospital. Among them, 120 cases were used as the training set, and 30 cases are used as the test set. After preprocessing and data augmentation, we trained the network and tested it on the test dataset. We evaluated segmentation performance through the Dice similarity coefficient (DSC), precision, recall, and Jaccard index (JI). Results: The average DSC, precision, recall, and JI of DARU‐Net reached 0.8066 ± 0.0956, 0.8233 ± 0.1255, 0.7913 ± 0.1304, and 0.6743 ± 0.1317. Compared with U‐Net and other deep learning methods, DARU‐Net was more accurate and stable. Conclusion: This work proposed an optimized U‐Net with channel and spatial attention mechanisms to segment uterine fibroids on preoperative MR images. Results showed that DARU‐Net was able to accurately segment uterine fibroids from MR images. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to establish a deep learning radiomics nomogram (DLRN) based on multiparametric MR images for predicting the response to neoadjuvant chemotherapy (NACT) in patients with locally advanced cervical cancer (LACC). Methods: Patients with LACC (FIGO stage IB-IIIB) who underwent preoperative NACT were enrolled from center 1 (220 cases) and center 2 (independent external validation dataset, 65 cases). Handcrafted and deep learning-based radiomics features were extracted from T2WI, DWI and contrast-enhanced (CE)-T1WI, and radiomics signatures were built based on the optimal features. Two types of radiomics signatures and clinical features were integrated into the DLRN for prediction. The AUC, calibration curve and decision curve analysis (DCA) were employed to illustrate the performance of these models and their clinical utility. In addition, disease-free survival (DFS) was assessed by Kaplan–Meier survival curves based on the DLRN. Results: The DLRN showed favorable predictive values in differentiating responders from nonresponders to NACT with AUCs of 0.963, 0.940 and 0.910 in the three datasets, with good calibration (all p > 0.05). Furthermore, the DLRN performed better than the clinical model and handcrafted radiomics signature in all datasets (all p < 0.05) and slightly higher than the DL-based radiomics signature in the internal validation dataset (p = 0.251). DCA indicated that the DLRN has potential in clinical applications. Furthermore, the DLRN was strongly correlated with the DFS of LACC patients (HR = 0.223; p = 0.004). Conclusion: The DLRN performed well in preoperatively predicting the therapeutic response in LACC and could provide valuable information for individualized treatment. [ABSTRACT FROM AUTHOR]

This correction notice from the journal "Frontiers in Endocrinology" addresses an error in the order of affiliations for Hongmei Dong in an article about carotid artery elasticity in non-obese PCOS patients. The correction does not impact the scientific conclusions of the original article. The authors have apologized for the mistake, and the article has been updated accordingly. [Extracted from the article]

Purpose: In upper eyelid blepharoplasty, most aesthetic surgeons and patients focus on improvements in the appearance of the upper eyelids, such as changing the vertical dimension of the palpebral fissure and the width of the pretarsal crease. Nevertheless, appropriately balanced periorbital aesthetics stemming from harmony between the eyelids and eyebrows is often ignored. The aim of this study was to explore the use of upper eyelid blepharoplasty to improve the overall periorbital aesthetics by enhancing the harmony between the eyes and eyebrows in young Asian women. Patients and Methods: From December 2019 to December 2020, 45 young Asian female patients underwent external incision upper eyelidplasty without ptosis repair or brow lift at The Second Affiliated Hospital of Harbin Medical University. The pre- and 6-month post-operative follow-up changes in the overall periorbital aesthetics were studied retrospectively. Results: The vertical position of the eyebrows in the upper face and shape of the brow apex were significantly improved after surgery. As a result, the height of the upper face was increased. Furthermore, the facial width proportion and midface ratio were closer to the ideal aesthetic golden ratio due to changes in the size of the periorbital area. All patients were satisfied with the result, and they achieved excellent surgical outcomes for not only the upper eyelids but also the overall periorbital region. Conclusion: This study revealed that upper eyelid blepharoplasty, which enhances the appearance of the upper eyelids while regulating the eyelid position and shape of the eyebrows by considering the eye to eyebrow ratio, optimizes the proportion of the periorbital area and improves the overall periorbital aesthetics. [ABSTRACT FROM AUTHOR]

Background: Silicone implants are currently the most widely used artificial materials in plastic surgery. Capsule formation following implant application is unavoidable. When the capsule is excessively thick and strongly contracted, it can lead to obvious symptoms, clinically known as capsular contracture. Biological factors have always been the focus of research on the capsule formation. As a growth factor, progranulin (PGRN) plays an important regulatory role in wound healing, tissue fibrosis, tumor proliferation and invasion, and inflammation regulation. At present, the research on the capsule mainly involves the regulation of tissue healing and fibrosis under the influence of inflammation. Because PGRN has a regulatory role in these processes, we believe that the study of both can provide a new theoretical basis and intervention sites for monitoring and inhibiting the development of the capsule. Methods: In this experiment, the effects of different surgical operations on the content of PGRN in the surgical site and plasma of rats were detected. Sprague-Dawley (SD) rat dermal fibroblasts were co-cultured by recombinant PGRN. The effects of r-PGRN on fibroblasts were detected by 5-ethynyl-2'-deoxyuridine (EdU) assay, wound healing assay and Western blot assay. Finally, the effect of PGRN on capsule formation and contracture was studied by changing the content of PGRN in the prosthesis in rats after operation. Results: Surgical trauma and silicone implant increased plasma and local PGRN levels in SD rats. PGRN can activate the TGF-β/SMAD signaling pathway in a dose-dependent manner, thereby promoting fibroblast proliferation, differentiation and migration and inhibiting apoptosis and enhancing cell function, thereby promoting capsule formation and contracture. Conclusion: PGRN promotes the formation and contracture of the silicone implant capsule in SD rats by activating the TGF-β/SMAD signaling pathway. This discovery may provide new therapeutic targets and detection indicators. [ABSTRACT FROM AUTHOR]