Objective To investigate the diagnostic efficiency of artificial intelligence(AI)in rib frac-ture under the computed tomography(CT)images with different reconstruction slice thickness.Methods The first CT images of 100 patients with rib fractures were selected,and the interval-free recon-struction was carried out with the thickness of 0.625 mm,1.250 mm,2.500 mm and 5.000 mm,respectively.The rib fracture screening function of AI was used to automatically detect the CT images of four groups,and the diagnostic efficiency of AI for rib fracture under different reconstruction thickness conditions was com-pared.Results The sensitivity of AI in the diagnosis of rib fracture at 0.625 mm,1.250 mm,2.500 mm and 5.000 mm thickness was 99.32%(436/439),98.41%(432/439),89.52%(393/439)and 83.60%(367/439),respectively.The false positive rate was 4.80%(22/458),0.92%(4/436),0.76%(3/396)and 0.27%(1/368).The diagnostic sensitivity of AI in 0.625 mm and 1.250 mm thickness was higher than that in 2.500 mm and 5.000 mm,and the difference was statistically significant(P<0.05),while there was no significant difference in the thickness of 0.625 mm and 1.250 mm.The false positive rate of AI in the diagnosis of 0.625 mm slice thickness was higher than that of 1.250 mm,2.500 mm and 5.000 mm,and the difference was sta-tistically significant(P<0.05),while there was no significant difference in the thickness of 1.250 mm,2.500 mm and 5.000 mm(P>0.05).Conclusion The diagnostic efficiency of AI in 1.250 mm CT images is better than that in 0.625 mm,2.500 mm and 5.000 mm CT images.

Objective To evaluate the value of high-energetic virtual monoenergetic imaging(MonoE),bone metal artifact reduction(O-MAR),and their combination based on dual-layer detector spectral computed tomography(DLCT)in removing the artifacts caused by lumbar metal implants.Methods Patients who undergone lumbar implant surgery and performed lumbar examination on DLCT after surgery were prospectively selected.MonoE from 100 to 200 keV with an interval of 20 keV were reconstructed.O-MAR and O-MAR combined with MonoE(O-MAR+MonoE)images were also reconstructed.The differences of objective and subjective image quality among the images were compared.Results There were 45 patients included in the study.With the increasing of keV of MonoE,the attenuation of the tissue with low-and high-density artifact on MonoE and O-MAR+MonoE was increased and decreased,respectively.140 keV MonoE was the best sequence for the artifact reduction and the display of soft tissue.200 keV MonoE and its combination with O-MAR showed the best performance in the display of the interface of metal and bone.However,O-MAR+200 keV MonoE had the lowest noise.Conclusion Compared to O-MAR and O-MAR combined with MonoE,high-energetic MonoE shows a good value in the reduction of metal artifacts caused by the lumbar metal implants.

Acceleration of tooth movement during orthodontic treatment is challenging,with osteoclast-mediated bone resorption on the compressive side being the rate-limiting step.Recent studies have demonstrated that mechanoreceptors on the surface of monocytes/macrophages,especially adhesion G protein-coupled receptors(aGPCRs),play important roles in force sensing.However,its role in the regulation of osteoclast differentiation remains unclear.Herein,through single-cell analysis,we revealed that CD97,a novel mechanosensitive aGPCR,was expressed in macrophages.Compression upregulated CD97 expression and inhibited osteoclast differentiation;while knockdown of CD97 partially rescued osteoclast differentiation.It suggests that CD97 may be an important mechanosensitive receptor during osteoclast differentiation.RNA sequencing analysis showed that the Rap1a/ERK signalling pathway mediates the effects of CD97 on osteoclast differentiation under compression.Consistently,we clarified that administration of the Rap1a inhibitor GGTI298 increased osteoclast activity,thereby accelerating tooth movement.In conclusion,our results indicate that CD97 suppresses osteoclast differentiation through the Rap1a/ERK signalling pathway under orthodontic compressive force.

Objective:To investigate the role of RNA m6A methylation in mediating cerebellar dysplasia through analyzing the phenotypes of the mouse cerebella and the expression of several key m6A regulators upon hypobaric hypoxia treatment.Methods:Five-day old C57/BL6 mice were exposed to hypobaric hypoxia for 9 days. The status of mouse cerebellar development was analyzed by comparing the body weights, brain weights and histological features. Immunostaining of cell-type-specific markers was performed to analyze the cerebellar morphology. Real-time PCR, Western blot and immunohistochemical staining were performed to detect the expression of key m6A regulators in the mouse cerebella.Results:Compared with the control, the body weights, brain weights and cerebellar volumes of hypobaric hypoxic mice were significantly reduced ( P<0.01). The expression of specific markers in different cells, including NeuN (mature neuron), Calbindin-D28K (Purkinje cell) and GFAP (astrocyte), was decreased in hypobaric hypoxic mouse cerebella ( P<0.01), accompanied with disorganized cellular structure. The expression of methyltransferase METTL3 was significantly down-regulated in the cerebella of hypobaric hypoxic mice ( P<0.05). Conclusions:Hypobaric hypoxia stimulation causes mouse cerebellar dysplasia, with structural abnormalities in mature granular neurons, Purkinje cells and astrocytes. Expression of METTL3 is decreased in hypobaric hypoxic mice cerebellum compared with that of normobaric normoxic mice, suggesting that its mediated RNA m6A methylation may play an important role in hypobaric hypoxia-induced mouse cerebellar dysplasia.

Objective:To investigate the mechanism by which baicalein alleviates osteoarthritis by regulating Sirtuin (Sirt) to inhibit the senescence of fibroblast-like synoviocytes (FLS).Methods:FLS were extracted from synovium of non-osteoarthritis patients (3 patients) and osteoarthritis patients (3 patients), and assessed the senescence of FLS in osteoarthritis patients by Western blot, β-galactosidase staining and immunofluorescence, and examined the changing levels of Sirt family proteins and mRNAs in FLS. The relative expression level of Sirt1 in FLS was knocked down by transfection with Sirt1 siRNA, and the antioxidative capacity and senescence degree of FLS were analyzed. Chondrocytes were co-cultured with FLS and functional changes in chondrocytes were detected by Western blot. After inducing FLS senescence with bleomycin (BLM), different concentrations of baicalein were administered to detect the expression levels of Sirt1, p16, and p21 proteins and intracellular reactive oxygen species (ROS). The expression level of Sirt1 in FLS was knocked down, and BLM and baicalein treatments were applied. The relative expression levels of Sirt1 and ROS were detected using Western blot and ROS assays. After BLM-induced FLS senescence, baicalein and Compound C were added. The relative expression levels of phosphorylated AMP-activated protein kinase (pAMPK), nuclear factor erythroid 2-related factor 2 (NRF2), p16, p21, and ROS were detected by Western blot and ROS assays.Results:The relative expression of p16 and p21 in FLS in the osteoarthritic group were 3.66±0.38 and 3.55±0.34, which were higher than those in non-osteoarthritis group 1.00±0.07 and 1.00±0.09 ( t=11.860, P<0.001; t=12.520, P<0.001). The relative expression levels of Sirt1 and Sirt6 in FLS in the osteoarthritis group were 0.30±0.04 and 0.16±0.01, which were smaller than those in the non-osteoarthritis group 1.00 ± 0.03 and 1.00±0.04 ( t=23.840, P<0.001; t=34.130, P<0.001). After baicalein treatment, the relative expression of ROS was 2.58±0.28, 1.65±0.14 and 1.00±0.24 in the BLM, BLM+Bai and control groups, respectively, with statistically significant differences between the groups ( F=35.700, P<0.001), which was greater in the BLM and BLM+Bai than in the control group, and lower in the BLM+Bai than in the BLM group ( P<0.05). The relative expression of pAMPK and NRF2 was 0.28±0.02 and 0.38±0.09 after Compound C+Baicalein treatment, which was lower than that of 0.56±0.07 and 0.60±0.08 in the BLM+Bai group ( P<0.05). The relative expression of ROS increased from 1.75±0.16 to 3.45±0.12 ( P<0.001). The proportion of positivity in the BLM+Bai+Compound C, BLM+Bai and control groups was 47.30%±4.29%, 18.18%±3.89% and 7.70%±3.53% ( F=109.700, P<0.001), respectively, with the BLM+Bai+Compound C group being higher than that in the BLM+Bai group ( P<0.05). Conclusion:The downregulation of Sirt1 expression in patients with osteoarthritis leads to FLS senescence and accelerates the progression of osteoarthritis. Baicalein can inhibit FLS senescence by activating Sirt1/AMPK/NRF2 pathway, which may delay the progression of osteoarthritis and improve the function of chondrocytes.

Stroma surrounding the tumor cells plays crucial roles for tumor progression. However, little is known about the factors that maintain the symbiosis between stroma and tumor cells. In this study, we found that the transcriptional regulator-signal transducer and activator of transcription 3 (Stat3) was frequently activated in cancer-associated fibroblasts (CAFs), which was a potent facilitator of tumor malignancy, and formed forward feedback loop with platelet-activating factor receptor (PAFR) both in CAFs and tumor cells. Importantly, PAFR/Stat3 axis connected intercellular signaling crosstalk between CAFs and cancer cells and drove mutual transcriptional programming of these two types of cells. Two central Stat3-related cytokine signaling molecules-interleukin 6 (IL-6) and IL-11 played the critical role in the process of PAFR/Stat3 axis-mediated communication between tumor and CAFs. Pharmacological inhibition of PAFR and Stat3 activities effectively reduced tumor progression using CAFs/tumor co-culture xenograft model. Our study reveals that PAFR/Stat3 axis enhances the interaction between tumor and its associated stroma and suggests that targeting this axis can be an effective therapeutic strategy against tumor malignancy.

Pulmonary hypertension (PH) is a life-threatening disease characterized by pulmonary vascular remodeling, in which hyperproliferation of pulmonary artery smooth muscle cells (PASMCs) plays an important role. The cysteine 674 (C674) in the sarcoplasmic/endoplasmic reticulum Ca²⁺ ATPase 2 (SERCA2) is the critical redox regulatory cysteine to regulate SERCA2 activity. Heterozygous SERCA2 C674S knock-in mice (SKI), where one copy of C674 was substituted by serine to represent partial C674 oxidative inactivation, developed significant pulmonary vascular remodeling resembling human PH, and their right ventricular systolic pressure modestly increased with age. In PASMCs, substitution of C674 activated inositol requiring enzyme 1 alpha (IRE1α) and spliced X-box binding protein 1 (XBP1s) pathway, accelerated cell cycle and cell proliferation, which reversed by IRE1α/XBP1s pathway inhibitor 4μ8C. In addition, suppressing the IRE1α/XBP1s pathway prevented pulmonary vascular remodeling caused by substitution of C674. Similar to SERCA2a, SERCA2b is also important to restrict the proliferation of PASMCs. Our study articulates the causal effect of C674 oxidative inactivation on the development of pulmonary vascular remodeling and PH, emphasizing the importance of C674 in restricting PASMC proliferation to maintain pulmonary vascular homeostasis. Moreover, the IRE1α/XBP1s pathway and SERCA2 might be potential targets for PH therapy.

Humans ; COVID-19 ; Epidemics ; Respiratory Tract Diseases ; Hospitalization

The Brodmann area(BA)-based map is one of the most widely used cortical maps for studies of human brain functions and in clinical practice;however,the molecular architecture of BAs remains unknown.The present study provided a global multiregional proteomic map of the human cerebral cortex by analyzing 29 BAs.These 29 BAs were grouped into 6 clusters based on similarities in proteomic patterns:the motor and sensory cluster,vision cluster,auditory and Broca's area cluster,Wernicke's area cluster,cingulate cortex cluster,and heterogeneous function cluster.We identified 474 cluster-specific and 134 BA-specific signature proteins whose functions are closely associated with specialized functions and disease vulnerability of the corresponding clus-ter or BA.The findings of the present study could provide explanations for the functional connec-tions between the anterior cingulate cortex and sensorimotor cortex and for anxiety-related function in the sensorimotor cortex.The brain transcriptome and proteome comparison indicates that they both could reflect the function of cerebral cortex,but show different characteristics.These pro-teomic data are publicly available at the Human Brain Proteome Atlas(www.brain-omics.com).Our results may enhance our understanding of the molecular basis of brain functions and provide an important resource to support human brain research.

Objective:To explore the value of different radiomics models based on machine learning in predicting the risk of distant recurrence and metastasis of triple-negative breast cancer after neoadjuvant therapy.Methods:The clinical and imaging data of 150 patients with triple-negative breast cancer (TNBC) confirmed by histopathology were retrospectively analyzed. All patients underwent neoadjuvant chemotherapy and surgical resection from August 2011 to May 2017 in Fudan University Shanghai Cancer Center and Ruijin Hospital, Shanghai Jiao Tong University School of Medicine. One hundred and nine patients from Shanghai Fudan University Shanghai Cancer Center were used as the training group, and 41 patients from Ruijin Hospital, Shanghai Jiao Tong University School of Medicine were used as the validation group. The features were extracted from dynamic contrast-enhanced MRI (DCE-MRI) before treatment and were added with time domain features innovatively. Least absolute shrinkage and selection operator cross validation and recursive feature elimination were applied to select features. Six different supervised machine learning algorithms (logistic regression, linear discriminant analysis, k-nearest neighbor, naive bayesian, decision tree, support vector machine) were used to predict the prognosis. ROC curve, accuracy and F1 measure were used to evaluate the performance of the six algorithms, and also verified by the validation group.Results:The support vector machine algorithm had the best predictive effect in the recurrence and metastasis model based on 15 features, with the highest area under curve (training group was 0.917, validation group was 0.859), and the highest accuracy rate (training group was 87.5%, validation group was 82.9%) and the highest F1 measure (training group was 0.800, validation group was 0.741). In addition, of the 15 imaging features, 12 were the time domain features and 3 were spatial features.Conclusion:With the help of the time domain features and machine learning algorithms, radiomics signatures based on preoperative DCE-MRI can help predict the distant prognosis for TNBC after neoadjuvant chemotherapy and provide support for clinical decision making and follow-up management.