A multi-channel collagen scaffold loaded with neural stem cells for the repair of spinal cord injury

Collagen scaffolds possess a three-dimensional porous structure that provides sufficient space for cell growth and proliferation,the passage of nutrients and oxygen,and the discharge of metabolites.In this study,a porous collagen scaffold with axially-aligned luminal conduits was prepared.In vitro biocompatibility analysis of the collagen scaffold revealed that it enhances the activity of neural stem cells and promotes cell extension,without affecting cell differentiation.The collagen scaffold loaded with neural stem cells improved the hindlimb motor function in the rat model of T8 complete transection and promoted nerve regeneration.The collagen scaffold was completely degraded in vivo within 5 weeks of implantation,exhibiting good biodegradability.Rectal temperature,C-reactive protein expression and CD68 staining demonstrated that rats with spinal cord injury that underwent implantation of the collagen scaffold had no notable inflammatory reaction.These findings suggest that this novel collagen scaffold is a good carrier for neural stem cell transplantation,thereby enhancing spinal cord repair following injury.This study was approved by the Animal Ethics Committee of Nanjing Drum Tower Hospital(the Affiliated Hospital of Nanjing University Medical School),China(approval No.2019AE02005)on June 15,2019.

Magnetic resonance cholangiopancreatography study of pancreaticobiliary maljunction and pancreaticobiliary diseases

AIM: To discuss the imaging anatomy about pancreaticobiliary ductal union, occurrence rate of pancreaticobiliary maljunction (PBM) and associated diseases in a Chinese population by using magnetic resonance cholangiopancreatography (MRCP).

Robust restoration of low-dose cerebral perfusion CT images using NCS-Unet

Cerebral perfusion computed tomography(PCT)is an important imaging modality for evaluating cerebrovascular diseases and stroke symptoms.With widespread public concern about the potential cancer risks and health hazards associated with cumulative radiation exposure in PCT imaging,considerable research has been conducted to reduce the radiation dose in X-ray-based brain perfusion imaging.Reducing the dose of X-rays causes severe noise and artifacts in PCT images.To solve this problem,we propose a deep learning method called NCS-Unet.The exceptional characteristics of non-subsampled contourlet transform(NSCT)and the Sobel filter are introduced into NCS-Unet.NSCT decomposes the convolved features into high-and low-frequency components.The decomposed high-frequency component retains image edges,contrast imaging traces,and noise,whereas the low-frequency component retains the main image information.The Sobel filter extracts the contours of the original image and the imaging traces caused by the contrast agent decay.The extracted information is added to NCS-Unet to improve its performance in noise reduction and artifact removal.Qualitative and quantitative analyses demonstrated that the proposed NCS-Unet can improve the quality of low-dose cone-beam CT perfusion reconstruction images and the accuracy of perfusion parameter calculations.

Differentiating gastric cancer and gastric lymphoma using texture analysis(TA)of positron emission tomography(PET)

Background:Texture analysis(TA)can quantify intra-tumor heterogeneity using standard medical images.The present study aimed to assess the application of positron emission tomography(PET)TA in the differential diagnosis of gastric cancer and gastric lymphoma.Methods:The pre-treatment PET images of 79 patients(45 gastric cancer,34 gastric lymphoma)between January 2013 and February 2018 were retrospectively reviewed.Standard uptake values(SUVs),first-order texture features,and second-order texture features of the grey-level co-occurrence matrix(GLCM)were analyzed.The differences in features among different groups were analyzed by the two-way Mann-Whitney test,and receiver operating characteristic(ROC)analysis was used to estimate the diagnostic efficacy.Results:InertiaGLCM was significantly lower in gastric cancer than that in gastric lymphoma(4975.61 vs.11,425.30,z=-3.238,P=0.001),and it was found to be the most discriminating texture feature in differentiating gastric lymphoma and gastric cancer.The area under the curve(AUC)of inertiaGLCM was higher than the AUCs of SUVmax and SUVmean(0.714 vs.0.649 and 0.666,respectively).SUVmax and SUVmean were significantly lower in low-grade gastric lymphoma than those in high grade gastric lymphoma(3.30 vs.11.80,2.40 vs.7.50,z=-2.792 and-3.007,P=0.005 and 0.003,respectively).SUVs and first-order greylevel intensity features were not significantly different between low-grade gastric lymphoma and gastric cancer.EntropyGLCM12 was significantly lower in low-grade gastric lymphoma than that in gastric cancer(6.95 vs.9.14,z=-2.542,P=0.011)and had an AUC of 0.770 in the ROC analysis of differentiating low-grade gastric lymphoma and gastric cancer.Conclusions:InertiaGLCM and entropyGLCM were the most discriminating features in differentiating gastric lymphoma from gastric cancer and low-grade gastric lymphoma from gastric cancer,respectively.PET TA can improve the differential diagnosis of gastric neoplasms,especially in tumors with similar degrees of fluorodeoxyglucose uptake.

Gd-EOB-DTPA-enhanced MRI radiomic features for predicting histological grade of hepatocellular carcinoma

Background:Prediction models for the histological grade of hepatocellular carcinoma(HCC)remain unsatisfactory.The purpose of this study is to develop preoperative models to predict histological grade of HCC based on gadolinium-ethoxybenzyl diethylenetriamine pentaacetic acid(Gd-EOB-DTPA)-enhanced magnetic resonance imaging(MRI)radiomics.And to compare the performance between artificial neural network(ANN)and logistic regression model.Methods:A total of 122 HCCs were randomly assigned to the training set(n=85)and the test set(n=37).There were 242 radiomic features extracted from volumetric of interest(VOI)of arterial and hepatobiliary phases images.The radiomic features and clinical parameters[gender,age,alpha-fetoprotein(AFP),carcinoembryonic antigen(CEA),carbohydrate antigen 19-9(CA19-9),alanine aminotransferase(ALT),aspartate transaminase(AST)]were selected by permutation test and decision tree.ANN of arterial phase(ANN-AP),logistic regression model of arterial phase(LR-AP),ANN of hepatobiliary phase(ANN-HBP),logistic regression mode of hepatobiliary phase(LR-HBP),ANN of combined arterial and hepatobiliary phases(ANN-AP+HBP),and logistic regression model of combined arterial and hepatobiliary phases(LR-AP+HBP)were built to predict HCC histological grade.Those prediction models were assessed and compared.Results:ANN-AP and LR-AP were composed by AST and radiomic features based on arterial phase.ANN-HBP and LR-HBP were composed by AFP and radiomic features based on hepatobiliary phase.ANN-AP+HBP and LR-AP+HBP were composed by AST and radiomic features based on arterial and hepatobiliary phases.The prediction models could distinguish between high-grade tumors[Edmondson-Steiner(E-S)grade III and IV]and low-grade tumors(E-S grade I and II)in both training set and test set.In the test set,the AUCs of ANN-AP,LR-AP,ANN-HBP,LR-HBP,ANN-AP+HBP and LR-AP+HBP were 0.889,0.777,0.941,0.819,0.944 and 0.792 respectively.The ANN-HBP was significantly superior to LR-HBP(P=0.001).And the ANN-AP+HBP was significantly superior to LR-AP+HBP(P=0.007).Conclusions:Prediction models consisting of clinical parameters and Gd-EOB-DTPA-enhanced MRI radiomic features(based on arterial phase,hepatobiliary phase,and combined arterial and hepatobiliary phases)could distinguish between high-grade HCCs and low-grade HCCs.And the ANN was superior to logistic regression model in predicting histological grade of HCC.

Clinical characteristics and outcomes of hypersensitivity pneumonitis: a population-based study in China

Backgrounds:Hypersensitivity pneumonitis (HP) is an immune-mediated interstitial lung disease (ILD) that develops in response to the inhalation of various antigens. The clinical pathologies are very complex and undetermined. The clinical features and outcomes of HP have not been fully elucidated. The aim of this study was to analyze the incidence, clinical features, and outcomes of HP patients and construct a simple clinical model for diagnosing chronic HP (CHP). Methods: The cohort study included 101 patients with HP admitted to the Nanjing Drum Tower Hospital from January 2009 to December 2017. The patients were categorized into acute HP (AHP, n = 72) and CHP (n = 29) groups according to the updated international criteria. The clinical, imaging, treatment, and follow-up data were retrospectively reviewed. All patients were followed up until December 31,2017. Statistical analysis was performed, and a clinical scoring system for CHP was constructed by SPSS 20.0 software. Results: The incidence of HP was 2.4% in ILD inpatients in our center. Patients in the CHP group were older =-2.212, P = 0.029), had more smokers (x^2 = 8.428, P = 0.004), and longer duration of symptoms (t =-4.852, P < 0.001) than those in the AHP group. Weight loss, crackles, digital clubbing, and cyanosis were more common in the CHP group than those in the AHP group (x^2 = 5.862, P < 0.001;x^2 = 8.997, P = 0.003;x^2 = 11-939, P = 0.001;and x^2 = 4.025, P = 0.045, respectively). On chest high-resolution computed tomography (HRCT), reticular patterns, traction bronchiectasis, and accompanying honeycombing were more common in CHP cases than those in AHP cases (x^2 = 101.000, P < 0.001;x^2 = 32.048, P < 0.001;a n d /2 = 36.568,P < 0.001, respectively). The clinical scoring system for CHP was established based on the clinical variables (age [A], duration of symptoms [D], smoking history [S], unidentified exposure [U], and chest HRCT [C];ADSUC)(area under the curve 0.935, 95% confidence interval: 0.883-0.987, P < 0.001). Eleven patients (15.3%) in the AHP group developed CHP, and unidentified exposure was an independent risk factor for the progression of disease (P = 0.038). The survival of patients with CHP, smoking history, unidentified antigens and fibrosis on Chest HRCT were significantly worse (P = 0.011, P = 0.001, F = 0.005, and P = 0.011, respectively) by Kaplan-Meier analysis. Cox multivariate regression analysis revealed that unidentified exposure and total lung volume (TLC pred%) were independent prognostic predictors for HP patients (P = 0.017 and P = 0.017, respectively). Conclusions: The clinical features and outcomes of the CHP patients differ from those of the AHP patients. ADSUC is a simple and feasible clinical model for CHP. Unidentified exposure is an independent risk factor for the progression of AHP to CHP. Unidentified exposure and a low baseline TLC pred% are independent predictors for survival in HP patients.

Acute exacerbation of idiopathic pulmonary fibrosis: usual interstitial pneumonitis vs.possible usual interstitial pneumonitis pattern

Background:The prognosis of acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is very poor with a high mortality.The aim of this study was to describe the clinical features and survival of patients with AE-IPF with usual pulmonary fibrosis (UIP) and possible UIP (P-UIP) pattern on chest high resolution computed tomography (HRCT).Methods:This retrospective study included 107 patients with AE-IPF admitted to Nanjing Drum Tower Hospital from January 2010 to December 2016.The subjects were divided into UIP (n =86) and P-UIP group (n=21) based on chest HRCT.Continuous variables were analyzed using Student's t test or Mann-Whimey U test.Categorical variables were analyzed using x2 test.Log-rank test was used for the survival analysis.Cox proportional models evaluated the risk factors for AE occurrence and survival.Results:The male,older patients,previous N-acetylcysteine use,elevated white blood cell (WBC) counts,and microbiology infection were more common in the UIP group than the P-UIP group (X2 =13.567,P < 0.001;z =-2.936,P =0.003;X2 =5.901,P =0.015;t =2.048,P =0.043;x2 =10.297,P =0.036,respectively).The percentage of AE with UIP pattern in idiopathic interstitial pneumonia (ⅡP) was significantly higher than P-UIP pattern (X2 =40.011,P < 0.001).Smoking was the risk factor for AE within 6 months after IPF diagnosis in the UIP group.The cumulative proportion survival of 30-days was significantly higher in the UIP group compared with the P-UIP group (x2 =5.489,P =0.019) despite of the similar overall survival in the two groups.Multivariate Cox regression analysis indicated WBC count,partial pressure of oxygen in artery (PaO2)/ffactional concentration of inspired oxygen (FiOz),and computed tomography (CT) score were the independent predictors for survival in the UIP group (hazard ratio [HR]:1.070,95% confidential interval [CI]:1.027-1.114,P=0.001;HR:0.992,95% CI:0.986-0.997,P=0.002;and HR:1.649,95% CI:1.253-2.171,P < 0.001,respectively).Conclusions:AE occurrence of UIP patients in IIP was significantly more than P-UIP cases.The short-term survival was better in the UIP group despite of the similar overall survival in the two groups.WBC count,PaO2/FiO2,and CT score were the independent predictors for survival in UIP subjects.

Corrigendum: Clinical characteristics and outcomes of hypersensitivity pneumonitis: a population-based study in China

Reference 1.Wang LJ,Cai HR,Xiao YL,Wang Y,Cao MS.Clinical characteristics and outcomes of hypersensitivity pneumonitis:a population-based study in China.Chin Med J 2019;132:1283–1292.doi:10.1097/CM9.0000000000000256.

Abnormal cortical surface-based spontaneous and functional connectivity in the whole brain in lifelong premature ejaculation patients

Recent research has highlighted structural and functional abnormalities in the cerebral cortex of patients with premature ejaculation(PE).These anomalies could play a pivotal role in the physiological mechanisms underlying PE.This study leveraged functional magnetic resonance imaging(fMRI),a noninvasive technique,to explore these neural mechanisms.We conducted resting-state fMRI scans on 36 PE patients and 22 healthy controls(HC),and collected data on Premature Ejaculation Diagnostic Tool(PEDT)scores and intravaginal ejaculation latency time(IELT).Employing a surface-based regional homogeneity(ReHo)approach,we analyzed local neural synchronous spontaneous activity,diverging from previous studies that utilized a volume-based ReHo method.Areas with significant ReHo differences between PE and HC groups underwent surface-based functional connectivity(FC)analysis.Significant discrepancies in ReHo and FC across the cortical surface were observed in the PE cohort.Notably,PE patients exhibited decreased ReHo in the left triangular inferior frontal gyrus and enhanced ReHo in the right middle frontal gyrus.The latter showed heightened connectivity with the left lingual gyrus and the right orbital superior frontal gyrus.Furthermore,a correlation between ReHo and FC values with PEDT scores and IELT was found in the PE group.Our findings,derived from surface-based fMRI data,underscore specific brain regions linked to the neurobiological underpinnings of PE.

Human infection with a novel avian-origin influenza A （H7N9） virus： serial chest radiographic and CT findings

Background Rapidly progressive pneumonia infection with H7N9 virus is a novel disease,and limited information is available concerning serial chest radiographic and computed tomography （CT） findings.The aim of this study was to evaluate the changes in serial radiologic findings in patients with H7N9 pneumonia.Methods The two institutional ethics review boards approved this retrospective study.This study included 10 patients with H7N9 pneumonia.All patients underwent chest radiologic examinations at different time points.Serial radiologic images were systematically analyzed.Results All patients showed abnormal results on initial chest radiography and CT.The initial radiographic abnormalities were unilateral （n=9） and bilateral （n=1）,including ground-glass opacities （GGOs） （n=5） and consolidation （n=5）.The initial CT findings consisted of unilateral （n=6） and bilateral （n=4）,including consolidation （n=10）,GGOs （n=10）,reticular opacities （n=2）,and pleural effusion （n=3）.Follow-up radiologic findings showed rapid development of consolidation or GGOs within two weeks after illness onset.Pneumomediastinum with secondary subcutaneous emphysema and pneumothorax were noted in two patients.Follow-up high resolution computed tomography （HRCT） after two weeks showed slow improvement in both size and opacity of the lesions.On HRCT after discharge,patients had substantial residual lesions such as irregular linear opacities,reticular opacities,parenchymal bands,traction bronchiectasis,and cystic lesions.Conclusions The most common radiologic findings at presentation are multifocal or diffuse areas of consolidation and GGOs in H7N9 pneumonia.HRCT in sequence can show more changes in rapid progression of disease and a slow decrease of both size and opacity of the lesions plays an important role in the evaluation of H7N9 pneumonia.

Versatile iron-vitamin K_(3) derivative-based nanoscale coordination polymer augments tumor ferroptotic therapy

Ferroptosis is a newly form of regulated cell death,which has attracted great attention for tumor therapy.Herein,we prepared nanoscale coordination polymer Fe-NQA particles to deliver iron and NQA(vitamin K3 derivative)into tumor cells,which synergistically promoted ferroptotic therapy for inhibiting tumor growth,preventing metastasis,and overcoming radioresistance.

Degradable Hybrid CuS Nanoparticles for Imaging-Guided Synergistic Cancer Therapy via Low-Power NIR-II Light Excitation

Near-infrared(NIR)-II light-excitable photonic agents capable of generating tumor hyperthermia and cytotoxic free radicals are promising for synergistic phototherapy of tumors.However,the lack of NIR-II excitable agents makes it challenging to achieve combinational tumor phototherapy.Here,the authors have reported on a tumor-targeting and degradable hybrid copper sulfide(CuS)nanoparticle(AIBA@CuS-FA)via loading a hydrophilic Azo initiator(AIBA)into an amphiphilic lipid-encapsulating CuS nanoparticle.AIBA@CuS-FA shows high photothermal conversion efficiency(PCE≈47.5%)at 1064 nm,enabling heat production to trigger tumor hyperthermia and thermal decomposition of AIBA into cytotoxic free alkyl radicals upon irradiation with a 1064-nm laser under low-power density(0.5 W/cm2).Moreover,alkyl radicals can drive degradation of AIBA@CuS-FA and embedded CuS nanodisks,releasing Cu^(2+)ions that can catalyze a Fenton-like reaction for hydroxyl radical(•OH)production to promote tumor therapy.Findings demonstrate promise for combinational photothermal therapy(PTT),oxygen-independent alkyl radical therapy,and chemodynamic therapy(CDT)of tumors.

Altered relationship between thickness and intrinsic activity amplitude in generalized tonic–clonic seizures

A thinner cortex has higher potential for binding GABA receptor A which is associated with larger amplitudes of intrinsic brain activity(i BA). However, the relationship between cortical thickness and i BA is unknown in intact and epileptic brains. To this end, we investigated the relationship between cortical thickness measured by highresolution MRI and surface-based i BA derived from resting-state functional MRI in normal controls(n = 82) andpatients with generalized tonic–clonic seizures(GTCS)only(n = 82). We demonstrated that the spatial distribution of cortical thickness negatively correlated with surface-based i BA amplitude at both whole-brain and within independent brain functional networks. In GTCS patients,spatial coupling between thickness and i BA amplitude decreased in the default mode, dorsal attention, and somatomotor networks. In addition, the vertex-wise acrosssubject thickness–i BA amplitude correspondence altered in the frontal and temporal lobes as well as in the precuneus in GTCS patients. The relationship between these two modalities can serve as a brain-based marker for detecting epileptogenic changes.