Protective effect and mechanism of mesenchymal stem cell-derived extracellular vesicle on radiation-induced liver injury / 器官移植

Objective To evaluate the protective effect and the underlying mechanism of mesenchymal stem cell-derived extracellular vesicle (MSC-EV) on radiation-induced liver injury and liver cell line injury in mouse models. Methods C57BL/6 mice were randomly divided into the blank group, model group and MSC-EV treatment group (treatment group), with 9 mice in each group. AML12 cells were randomly divided into the control group, irradiation group and MSC-EV intervention group (intervention group). Animal and cell models with radiation-induced injury were established by one-time 15 Gy and 6 Gy X-ray irradiation, respectively. At 48 h after irradiation, liver tissues and serum samples of mice were collected and prepared for subsequent experiments. At 15 h post-irradiation, cell experiment was carried out. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and content of malondialdehyde (MDA) in liver tissues and cells were measured. The relative expression levels of interleukin (IL)-1β, IL-6, transforming growth factor (TGF)-β and CXC chemokine ligand (CXCL)10 messenger RNA (mRNA) were detected by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR). Liver tissues were prepared for hematoxylin-eosin (HE) staining to calculate liver pathological injury score. The apoptosis of liver tissues and cells was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and propidiumiodide (PI) staining, respectively. The expression levels of glutathione peroxidase 4 (GPX4) and ferroptosis suppressor protein 1 (FSP1) proteins were detected by Western blot. The production level of reactive oxygen species (ROS) was detected by dihydroethidine (DHE) staining. The fluorescence intensity of mitochondrial permeability transition pore (mPTP) was determined. Results Compared with the blank group, serum levels of AST and ALT were up-regulated, and the relative expression levels of IL-1β, TGF-β and CXCL10 mRNA in the mouse liver tissues were up-regulated, and MDA content was increased, liver injury score was elevated, cell apoptosis rate was increased, intracellular ROS level was elevated, and the relative expression levels of GPX4 and FSP1 proteins in the mouse liver tissues were down-regulated in the model group, and the differences were statistically significant (all P<0.05). Compared with the model group, serum levels of AST and ALT were decreased, and the relative expression levels of IL-1β, TGF-β and CXCL10 mRNA in the liver tissues of mice were down-regulated, MDA content was declined, liver injury score was declined, cell apoptosis rate was decreased, intracellular ROS level was decreased, and the relative expression levels of GPX4 and FSP1 proteins in the liver tissues of mice were up-regulated in the treatment group, and the differences were statistically significant (all P<0.05). Compared with the control group, cell apoptosis rate was increased, intracellular ROS level was elevated, the fluorescence intensity of mPTP was weakened, the relative expression levels of IL-1β, TGF-β and IL-6 mRNA were up-regulated, MDA content was increased, and the relative expression levels of GPX4 and FSP1 proteins were down-regulated in the irradiation group, and the differences were statistically significant (all P<0.05). Compared with the irradiation group, cell apoptosis rate was declined, intracellular ROS level was decreased, the fluorescence intensity of mPTP was strengthened, the relative expression levels of IL-1β, TGF-β and IL-6 mRNA were down-regulated, MDA content was decreased and the relative expression levels of GPX4 and FSP1 proteins were up-regulated in the intervention group, and the differences were statistically significant (all P<0.05). Conclusions MSC-EV may effectively alleviate radiation-induced liver injury by reducing ferroptosis of liver cells, enhancing antioxidant level and decreasing the production of lipid peroxide, thereby effectively alleviating radiation-induced liver injury.

Feasibility study of chest ultra-low dose CT with deep learning reconstruction for lung cancer screening / 中华放射学杂志

Objective:To investigate the feasibility of chest ultra-low dose CT (ULDCT) using deep learning reconstruction (DLR) for lung cancer screening, and to compare its image quality and nodule detection rate with ULDCT iterative reconstruction (Hybrid IR) and conventional dose CT (RDCT) Hybrid IR.Methods:The patients who underwent chest CT examination for pulmonary nodules in Peking Union Medical College Hospital from October 2020 to March 2021 were prospectively included and underwent chest RDCT (120 kVp, automatic tube current), followed by ULDCT (100 kVp, 20 mA). The RDCT images were reconstructed with Hybrid IR (adaptive iterative dose reduction 3D,AIDR 3D), and ULDCT was reconstructed with AIDR3D and DLR. Radiation dose parameters and nodule numbers were recorded. Image quality was assessed using objective noise, signal-to-noise ratio (SNR) of the main trachea and left upper lobe, subjective image scores of the lung and nodules. Subjective scores were scored by 2 experienced radiologists on a Likert 5-point scale. The difference of radiation dose was compared with paired t-test between ULDCT and RDCT.The differences of quantitative indexes, objective image noise and subjective scores of the three reconstruction methods were compared with one-way analysis of variance or Friedman test. Results:Forty-five patients were enrolled, including 17 males and 28 females, aged from 32 to 74 (55±11) years. The radiation dose of ULDCT was (0.17±0.01) mSv, which was significantly lower than that of RDCT [(1.35±0.41) mSv, t=15.46, P<0.001]. There were significant differences in the image noise and SNR in the trachea and lung parenchyma and in the CT value of the trachea among ULDCT-AICE, ULDCT-AIDR 3D and RDCT-AIDR 3D images ( P<0.05). Image noise in the trachea and lung parenchyma and CT value in the trachea of ULDCT-AICE were significantly lower than those of ULDCT-AIDR 3D ( P<0.05) and comparable to RDCT-AIDR 3D ( P>0.05). There were significant differences in subjective image scores of the lung and nodules among ULDCT-AICE, ULDCT-AIDR 3D and RDCT-AIDR 3D images (χ2=50.57,117.20, P<0.001). Subjective image scores of the lung and nodules for ULDCT-AICE were significantly higher than those of ULDCT-AIDR 3D ( P<0.05), and non-inferior to RDCT-ADIR 3D ( P>0.05). All 72 clinically significant nodules detected on RDCT-ADIR 3D were also noted on ULDCT-AICE and ULDCT-AIDR 3D images. Conclusions:Chest ULDCT using DLR can significantly reduce the radiation dose, and compared with Hybrid IR, it can effectively reduce the image noise and improve SNR, and display the pulmonary nodules well. The image quality and nodule detection are not inferior to RDCT Hybrid IR routinely used in clinical practice.

The clinical value of deep learning reconstruction in low-dose CT pulmonary angiography / 中华放射学杂志

Objective:To explore the effect of deep learning reconstruction (DLR) on radiation dosage reduction and image quality of CTPA compared with hybrid iterative reconstruction (HIR).Methods:A total of 100 patients with suspected pulmonary embolism (APE) or indications for CTPA due to other pulmonary artery diseases in Peking Union Medical College Hospital from December 2020 to April 2021 were prospectively enrolled and divided into HIR group and DLR group according to block randomization, with 50 cases in each group. The patient′s gender, age and body mass index (BMI) were recorded. HIR group and DLR group underwent standard deviation (SD)=8.8 and SD=15 CTPA protocols in combination with HIR and DLR algorithm respectively. Other scanning parameters and contrast medium injection plan were the same. The effective dose (ED) and size-specific dose estimate (SSDE) were calculated. Regions of interest (ROIs) were drawn in the lumen of Grade 1-3 pulmonary arteries and bilateral paravertebral muscles. The corresponding CT and SD values were recorded to acquire signal to noise ratio (SNR) and contrast noise ratio (CNR). Based on a double-blind method, two radiologists evaluated the subjective noise, visualization of pulmonary arteries, and diagnostic confidence of the two groups by 5-point Likert scales. The inconsistent results were judged comprehensively by the third radiologist. Independent samples t-test was used to compare the demographic data, radiation dosage and quantitative image quality of the two groups. Mann-Whitney U test was used to compare the subjective noise, visualization of pulmonary arteries and diagnostic confidence between the two groups. Linear weighted Kappa coefficient was calculated to analyze the consistency of the qualitative scores between the two radiologists. Results:There were no significant differences in gender, age and BMI between the two groups ( P>0.05). The CT values of Grade1-3 pulmonary arteries and paravertebral muscle had no significant differences ( P>0.05). Compared with HIR group, the ED and SSDE in DLR group decreased by about 35% to 1.3 mSv and 4.20 mGy respectively, while the SNR (30±5) and CNR (26±5) of CTPA images were higher in DLR group than those in HIR group (23±5 and 20±5, with t=-6.60 and -5.90, respectively, both P<0.001). The subjective noise score was higher in DLR group than that in HIR group ( Z=-7.34, P<0.001). In addition, two radiologists showed excellent interobserver agreement in DLR group (Kappa=0.847, 95%CI 0.553-1.000). No significant differences were found in visualization of pulmonary arteries and diagnostic confidence between the two groups ( P>0.05). Conclusion:DLR further reduced the radiation dosage and improved the image quality of CTPA, with no detriment to diagnostic confidence. Thus DLR is worthy of clinical promotion.

Application value of deep learning reconstruction to improve image quality of low-dose chest CT / 中华放射学杂志

Objective:To evaluate the effectiveness of deep learning reconstruction (DLR) compared with hybrid iterative reconstruction (Hybrid IR) in improving the image quality in chest low-dose CT (LDCT).Methods:Seventy-seven patients who underwent LDCT scan for physical examination or regular follow-up in Peking Union Medical College Hospital from October 2020 to March 2021 were retrospectively included. The LDCT images were reconstructed with Hybrid IR at standard level (Hybrid IR Stand) and DLR at standard and strong level (DLR Stand and DLR Strong). Regions of interest were placed on pulmonary lobe, aorta, subscapularis muscle and axillary fat to measure the CT value and image noise. The signal to noise ratio (SNR) and contrast to noise ratio (CNR) were calculated. Subjective image quality was evaluated using Likert 5-score method by two experienced radiologists. The number and features of ground-glass nodule (GGN) were also assessed. If the scores of the two radiologists were inconsistent, the score was determined by the third radiologist. The objective and subjective image evaluation were compared using the Kruskal-Wallis test, and the Bonferroni test was used for multiple comparisons within the group.Results:Among Hybrid IR Stand, DLR Stand and DLR Strong images, the CT value of pulmonary lobe, aorta, subscapularis muscle and axillary fat had no significant differences (all P>0.05), but the image noise and SNR of pulmonary lobe, aorta, subscapularis muscle and axillary fat had significant differences(all P<0.05), and the CNR of images had significant difference( P<0.05), too. The CNR of Hybrid IR Stand images, DLR stand images and DLR strong images were 0.71 (0.49, 0.88), 1.06 (0.78, 1.32) and 1.14 (0.84, 1.48), respectively. Compared with Hybrid IR images, DLR images had lower objective and subjective image noise,higher SNR and CNR (all P<0.05). The scores of DLR images were superior to Hybrid IR images in identifying lung fissures, pulmonary vessels, trachea and bronchi, lymph nodes, pleura, pericardium and GGN (all P<0.05). Conclusions:DLR significantly reduced the image noise, and DLR images were superior to Hybrid IR images in identifying GGN in chest LDCT while maintaining superior image quality at relatively low radiation dose levels. Thus DLR images can improve the safety of lung cancer screening and pulmonary nodule follow-up by CT.

TRPV4 Regulates Soman-Induced Status Epilepticus and Secondary Brain Injury via NMDA Receptor and NLRP3 Inflammasome / 神经科学通报·英文版

Nerve agents are used in civil wars and terrorist attacks, posing a threat to public safety. Acute exposure to nerve agents such as soman (GD) causes serious brain damage, leading to death due to intense seizures induced by acetylcholinesterase inhibition and neuronal injury resulting from increased excitatory amino-acid levels and neuroinflammation. However, data on the anticonvulsant and neuroprotective efficacies of currently-used countermeasures are limited. Here, we evaluated the potential effects of transient receptor vanilloid 4 (TRPV4) in the treatment of soman-induced status epilepticus (SE) and secondary brain injury. We demonstrated that TRPV4 expression was markedly up-regulated in rat hippocampus after soman-induced seizures. Administration of the TRPV4 antagonist GSK2193874 prior to soman exposure significantly decreased the mortality rate in rats and reduced SE intensity. TRPV4-knockout mice also showed lower incidence of seizures and higher survival rates than wild-type mice following soman exposure. Further in vivo and in vitro experiments demonstrated that blocking TRPV4 prevented NMDA receptor-mediated glutamate excitotoxicity. The protein levels of the NLRP3 inflammasome complex and its downstream cytokines IL-1β and IL-18 increased in soman-exposed rat hippocampus. However, TRPV4 inhibition or deletion markedly reversed the activation of the NLRP3 inflammasome pathway. In conclusion, our study suggests that the blockade of TRPV4 protects against soman exposure and reduces brain injury following SE by decreasing NMDA receptor-mediated excitotoxicity and NLRP3-mediated neuroinflammation. To our knowledge, this is the first study regarding the “dual-switch” function of TRPV4 in the treatment of soman intoxication.

Chest High-resolution Computed Tomography Imaging Features of Lung Involvement in Rheumatoid Arthritis / 中国医学科学院学报

To explore the chest high-resolution computed tomography (HRCT) features in patients with rheumatoid arthritis (RA) complicated with pulmonary involvement. Totally 161 patients with RA with lung involvement were collected from June 2014 to May 2018. The chest HRCT findings were retrospectively analyzed. According to the imaging features as well as the results of history taking,pulmonary function test,pathology,and bronchoalveolar lavage fluid test,RA-related lung diseases (RA-LD) were classified and their clinical characteristics were compared. These 161 RA-LD patients (56 males and 105 females) whose mean age at diagnosis was (60.7±12.8) years (14-85 years) included 87 cases of usual interstitial pneumonia (UIP) (including 16 cases of possible UIP),44 cases of non-specific interstitial pneumonia (NSIP),10 cases of organizing pneumonia,7 cases of lymphocytic interstitial pneumonia,9 cases of small airway disease (SAD) (including 8 cases of bronchiolitis obliterans and 1 case of follicular bronchiolitis),and 4 other lung manifestations (including 3 cases of diffuse alveolar hemorrhage and 1 case of rheumatoid nodules). The UIP group had the oldest average age [(63.3±12.1) years old] and the highest smoking rate (41.4%). The SAD group had the youngest average age [(54.7±15.1) years old] and there was no smoking history. There were significant differences between these two groups (=0.020,<0.001). Seventy patients (43.5%) with RA-LD were complicated with pleural lesions. RA involving the lung is common and has varied imaging manifestations,with interstitial lung diseases (mainly UIP and NSIP) being the most important manifestations. RA patients should undergo lung HRCT as early as possible to identify the lung involvement and related types.

Preliminary Study on Clinical Features and CT Findings of Common-type Coronavirus Disease 2019 Patients in Peking Union Medical College Hospital / 中国医学科学院学报

To summarize the clinical characteristics and chest CT findings of coronavirus disease 2019(COVID-19)patients in Peking Union Medical College Hospital(PUMCH). A total of 13 patients with COVID-19 confirmed at PUMCH from January 20 to February 6,2020 were selected as the research subjects.Their epidemiological histories,clinical characteristics,laboratory tests,and chest CT findings were analyzed retrospectively.The location,distribution,density,and other accompanying signs of abnormal lung CT lesions were recorded,and the clinical types of these patients were assessed. The clinical type was "common type" in all these 13 patients aged(46.8±14.7)years(range:27-68 years).Ten patients had a travel history to Wuhan or direct contact with patients from Wuhan,2 cases had recent travel histories,and 1 case had a travel history to Beijing suburb.The white blood cell(WBC)count was normal or decreased in 92.3% of the patients and the lymphocyte count decreased in 15.4% of the patients.Twelve patients(92.3%)had a fever,among whom 11 patients were admitted due to fever and 2 patients(15.4%)had low fever.Eight patients(61.5%)had dry cough.The CT findings in these 13 patients were all abnormal.The lesions were mainly distributed along the bronchi and under the pleura.The lesions were relatively limited in 8 patients(affecting 1-3 lobes,predominantly in the right or left lower lobe),and diffuse multiple lesions of bilateral lungs were seen in 5 patients.The CT findings mainly included ground glass opacities(GGOs)(=10,76.9%),focal consolidation within GGOs(=7,53.8%),thickened vascular bundle passing through the lesions(=10,76.9%),bronchial wall thickening(=12,92.3%),air bronchogram(=10,76.9%),vacuole signs in the lesions(=7,53.8%),fine reticulation and interlobular septal thickening(=3,23.1%),reversed halo-sign(=2,15.4%),crazy-paving pattern(=2,15.4%),and pleural effusion(=2,15.4%). Most of our patients diagnosed with COVID-19 at PUMCH had a travel history to Wuhan or direct contact with patients from Wuhan.The first symptoms of COVID-19 mainly include fever and dry cough,along with normal or reduced counts of WBC and lymphocytes.CT may reveal that the lesions distribute along the bronchi and under the pleura;they are typically localized GGOs in the early stage but can become multiple GGOs and infiltrative consolidation in both lungs in the advanced stage.Scattered vacuole signs may be visible inside the lesions in some patients.

Comparative study of different anastomosis methods in laparoscopic distal gastrectomy for gastric cancer / 中国基层医药

Objective@#To explore the value of different anastomosis methods in laparoscopic distal gastrectomy.@*Methods@#From January 2014 to January 2016, 120 patients with distal gastric cancer in Weihai Central Hospital were selected and divided into the observation group and the control group according to the random digital table method, with 60 cases in each group.Triangular anastomosis was used in the observation group, while tubular anastomosis was used in the control group.The operative conditions, pain and complications were compared between the two groups.After 1-4 years of follow-up, the prognosis of the two groups was compared.@*Results@#Compared with the control group, the operation time of the observation group was shorter[(165.2±55.2)min vs.(188.2±59.3)min], the time of anastomosis was shorter[(22.6±8.1)min vs.(29.6±9.1)min], and the amount of bleeding was less[(88.6±29.2)mL vs.(107.5±49.1)mL], the differences were statistically significant (t=2.199, 4.451, 2.563, all P<0.05). Compared with the control group, the VAS scores of 1d[(3.5±1.1)points vs.(5.2±1.9)points]and 3d[(1.9±0.7)points vs.(3.0±1.5)points] were lower in the observation group, and the differences were statistically significant (t=5.998, 5.148, all P<0.05). There was no statistically significant difference in the incidence of postoperative complications between the two groups (P>0.05). After 1-4 years of follow-up, the overall survival rates in the observation group and the control group were 72.0% and 66.0%, respectively, and the median survival time was 42.4 months and 42.9 months, respectively.There was no statistically significant difference in survival between the two groups (χ2=0.310, P>0.05).@*Conclusion@#The trigonometric anastomosis is reliable in laparoscopic distal gastrectomy for gastric cancer, and it can shorten the time of anastomosis, reduce the amount of bleeding, and improve the postoperative pain of the patients.

Preliminary value of CT radiomics in predicting anaplastic lymphoma kinase fusion gene expression in lung adenocarcinoma / 中华放射学杂志

Objective@#To explore the value of quantitative CT radiomics features in predicting the anaplastic lymphoma kinase (ALK) mutation status in lung adenocarcinoma patients.@*Methods@#This retrospective study reviewed one hundred and ninety-five lung adenocarcinoma patients (including 60 patients with ALK mutation) whose ALK genetic test results were available from Nov 2015 to May 2018 in PUMCH. VOIs were labeled by an automatic pulmonary nodule detection and segmentation algorithm and were later revised and confirmed by two senior radiologists. The PyRadiomics tools were used to resample the labeled regions, followed by image pre-processing (Wavelet filter or Laplacian of Gaussian (LoG) filter) and feature extraction. Normalized features were selected based on their representativeness on Dr. Wise research platform. Multivariate logistic regression was performed to develop prediction models of ALK mutation gene based on different image pre-processing techniques and different radiomics feature types. The results were validated by ten runs of five-fold cross validation. ROC curve analysis and Delong test were used to compare the predictive performance among models.@*Results@#Fifteen radiomics features with the highest representativeness were selected from the original 1 232 features. The prediction model based on these radiomics features showed good performance (AUC=0.88 in the training set and 0.78 in the validation set) and was not significantly different from the prediction models based on radiomics features of different pre-processing images (AUC=0.76, P=0.1, original CT images; AUC=0.75, P=0.3, Wavelet-filtered images; AUC=0.76, P=0.2, LoG-filtered images). Among the models built with radiomics features of different types, the one based on GLCM feature (a subtype of texture feature) showed the best performance in predicting ALK genetic status (AUC=0.83, accuracy=0.74, sensitivity=0.85 and specificity=0.69). The model based on first-order statistic features had an AUC of 0.80.@*Conclusion@#Quantitative CT radiomics features have a good potential to anticipate the expression of ALK fused gene in patients with lung adenocarcinoma.

Effect of Kinesio Taping on Chronic Nonspecific Low Back Pain: A Meta-analysis / 中国康复理论与实践

Objective:To evaluate the effect of Kinesio taping on chronic nonspecific low back pain (CNLBP). Methods:The Cochrane Library, PubMed, Web of Science, CNKI, CBM, VIP, and Wanfang Data were searched for the randomized controlled trials (RCT) about the effect of Kinesio taping on CNLBP from establishment to January, 2019. The included studies were evaluated according to the method recommended by the Cochrane Collaboration. RevMan 5.3 software was used to analyze the extracted data. Results:Finally, nine RCTs involving 545 patients were included. Meta-analysis showed that the effect of Kinesio taping was significantly different in the improvement of pain compared with the non-stimulated group (MD = -0.76, 95%CI: -1.43 to -0.08, P = 0.03), the difference might be significant compared with the sham stimulation group (MD = -1.10, 95%CI: -2.22 to 0.02, P = 0.05); For improving dysfunction, the Oswestry Disability Index (ODI) scores were better in the Kinesio taping group than in the non-stimulation group (MD = -6.02, 95%CI: -8.63 to -3.41, P < 0.001) and the sham stimulation group (MD = -4.11, 95%CI: -5.82 to -2.41, P < 0.001), however, their was no significant difference in Roland Morris Disability Questionnaire (RMDQ) score between the Kinesio taping group and the non-stimulated group (MD = 0.69, 95%CI: -2.35 to 3.74, P = 0.66), and between the Kinesio taping group and the sham stimulation group (MD = -0.17, 95%CI: -1.43 to 1.08, P = 0.78). Conclusion:For the patients with CNLBP, the intervention of Kinesio taping could alleviate pain and improve function.

Comparative study of different anastomosis methods in laparoscopic distal gastrectomy for gastric cancer / 中国基层医药

Objective To explore the value of different anastomosis methods in laparoscopic distal gastrectomy.Methods From January 2014 to January 2016,120 patients with distal gastric cancer in Weihai Central Hospital were selected and divided into the observation group and the control group according to the random digital table method,with 60 cases in each group.Triangular anastomosis was used in the observation group,while tubular anastomosis was used in the control group.The operative conditions,pain and complications were compared between the two groups.After 1-4 years of follow-up,the prognosis of the two groups was compared.Results Compared with the control group,the operation time of the observation group was shorter[(165.2 ± 55.2)min vs.(188.2 ± 59.3)min],the time of anastomosis was shorter[(22.6 ± 8.1) min vs.(29.6 ± 9.1) min],and the amount of bleeding was less [(88.6 ± 29.2) mL vs.(107.5 ± 49.1) mL],the differences were statistically significant (t =2.199,4.451,2.563,all P ＜ 0.05).Compared with the control group,the VAS scores of 1d[(3.5 ± 1.1) points vs.(5.2 ± 1.9) points] and 3d [(1.9 ± 0.7) points vs.(3.0 ± 1.5) points] were lower in the observation group,and the differences were statistically significant (t =5.998,5.148,all P ＜ 0.05).There was no statistically significant difference in the incidence of postoperative complications between the two groups (P ＞ 0.05).After 1-4 years of follow-up,the overall survival rates in the observation group and the control group were 72.0％ and 66.0％,respectively,and the median survival time was 42.4 months and 42.9 months,respectively.There was no statistically significant difference in survival between the two groups (x2 =0.310,P ＞ 0.05).Conclusion The trigonometric anastomosis is reliable in laparoscopic distal gastrectomy for gastric cancer,and it can shorten the time of anastomosis,reduce the amount of bleeding,and improve the postoperative pain of the patients.

Imaging Findings of Pulmonary Cryptococcosis / 中国医学科学院学报

Pulmonary cryptococcosis(PC)is a fungal infection that can be easily misdiagnosed due to its non-specific clinical features and imaging findings.This article reviews the imaging findings of PC,their relationships with pathology and immune status,and differential diagnosis of PC with other disease,so as to improve the clinical management of PC.

Features and Prospects of Dual-energy Computed Tomography for Evaluation of Lung Cancer / 中国医学科学院学报

Dual-energy computed tomography,with fast image acquisition at two different X-ray energies,enables material-specific and spectral imaging,which offers objective and quantitative parameters for tumor detection,characterization,staging,and treatment monitoring without increasing radiation exposure.This article reviews the applications of dual-energy computed tomography technique and its applications in the evaluation of lung cancer and elucidates its future developments.

The serum homocysteine level in patients with acute ischemic stroke (AIS) after thrombolysis and its relationship with clinical outcomes

SUMMARY OBJECTIVE The present study aims to investigate whether hyperhomocysteinemia (HHcy) affects the outcomes of the thrombolytic treatment for patients with AIS. METHODS A sample of 120 AIS patients were recruited and grouped according to their serum homocysteine (Hcy) levels. The National Institute of Health Stroke Scale (NIHSS) was obtained before treatment and 7 days after it to evaluate neurological outcomes; modified Rankin Scale (mRS) was obtained 12 weeks later to assess functional outcomes. Receiver operating characteristic curve (ROC) was used to demonstrate the relationship between serum Hcy level and the outcomes after tPA treatment. RESULTS The serum Hcy level of 120 patients was of 27.57±20.17μmol/L. The NIHSS scores of the patients in the low Hcy level group were remarkably lower compared to those in the high-level group (p<0.05), after 7 days of treatment. In addition, the mRS scores of the patients in the low Hcy level group, after 12 weeks, were remarkably lower compared to those in the high-level group (p<0.01). ROC demonstrated that the serum Hcy level is related to the clinical outcomes of thrombolytic treatment with moderate specificity (80.3%) and sensitivity (58.2%). CONCLUSION In conclusion, higher serum Hcy levels can indicate poorer clinical outcomes of thrombolytic treatment in patients with AIS.

RESUMO OBJETIVO O presente estudo tem por objetivo investigar se a hiperhomocisteinemia (HHcy) afeta os resultados do tratamento trombolítico em pacientes com AVCI agudo. METODOLOGIA Uma amostra de 120 pacientes AVCI agudo foi recrutada e agrupada de acordo com os níveis séricos de homocisteína (Hcy). Uma avaliação nos padrões do National Institute of Health Stroke Scale (NIHSS) foi obtida antes do tratamento e 7 dias após ele para avaliar desfechos neurológicos e a escala de Rankin modificada foi utilizada 12 semanas depois para avaliar os desfechos funcionais. A curva ROC (Receiver Operating Caracteristic) foi utilizada para demonstrar a relação entre os níveis séricos de Hcy e os desfechos após tratamento com t-PA. RESULTADOS Os níveis séricos de Hcy de 120 pacientes foi de 27,57±20,17μmol/L. Os escores NIHSS dos pacientes no grupo de baixo nível de Hcy foram notavelmente mais baixos em comparação àqueles do grupo de nível mais alto (p<0,05), após 7 dias de tratamento. Além disso, os escores mRS dos pacientes no grupo de baixo nível de Hcy, após 12 semanas, foram consideravelmente mais baixos em comparação com os do grupo de alto nível (p<0,01). A curva ROC demonstrou que o nível sérico de Hcy tem relação com os desfechos clínicos do tratamento trombolítico com especificidade moderada (80,3%) e sensibilidade (58,2%). CONCLUSÃO Podemos concluir então que níveis séricos mais altos de Hcy podem prever desfechos clínicos piores para o tratamento trombolítico em pacientes com AVCI agudo.

Diagnostic value of quantitative dual-source CT dual-energy iodine maps combined with morphological CT features in assessing histological subtypes of lung cancer / 中华放射学杂志

Objective To investigate the clinical usefulness of quantitative dual-source dual-energy CT (DECT) iodine enhancement metrics combined with morphological CT features in distinguishing different lung cancer subtypes. Methods One hundred and sixty-two consecutive patients suspected with lung cancer were prospectively enrolled and underwent DECT in arterial phase prior to biopsy or surgery.Tumor histological subtypes were determined in 110 patients. Two radiologists interpreted CT morphologic features of 110 lesions in a consensual manner. In addition, two radiologists independently contoured lesions and placed regions of interest in descending aorta or subclavian artery on the same section for normalization , from which automated computer measurements were generated:iodine density and iodine ratio (the ratio of iodine density of lesion to that of artery on the same section). DECT metrics and morphological CT features were compared among different lung cancer subtypes. Chi-square was used to compare qualitative parameters. One way ANOVA was used to compare quantitative parameters satisfying normal distribution, while those parameters not satisfying normal distribution or ranked data were compared by Kruskal-Wallis rank sum test. Multinomial logistic regression models were used to differentiate the histological subtypes of lung cancer: adenocarcinoma, squamous cell carcinoma (SCC), small cell lung cancer (SCLC). Results There were 48 cases of adenocarcinomas, 36 cases of SCC and 26 cases of SCLC. In analysis of CT features, tumor diameter, distribution, spiculation, pleural retraction, vascular involvement, confluent mediastinal lymphadenopathy, encasement of mediastinal structures and enhancement heterogeneity showed statistical difference (all P<0.05). The diameter of SCC[(5.73 ± 3.67)cm] and SCLC [(6.08 ± 4.39)cm] were larger than adenocarcinoma [(3.75 ± 2.80 cm)] (H=13.806,P<0.05). Adenocarcinomas were mostly located in the periphery (31 cases), while SCC (26 cases) and SCLC (21 cases) were mainly centrally located. Spiculation was mostly found in adenocarcinoma (44 cases) rather than SCLC (13 cases). Pleural retraction was mostly observed in adenocarcinoma (36 cases) rather than SCC (10 cases) and SCLC (5 cases). Vascular involvement was mostly found in SCLC (19 cases) rather than adenocarcinoma (15 cases). Confluent mediastinal lymphadenopathy was more frequently found in SCLC (15 cases) compared with adenocarcinoma (3 cases) and SCC (4 cases). Encasement of mediastinal structures was mostly found in SCLC (13 cases) rather than adenocarcinoma (7 cases). Homogeneous enhancement was more frequently found in SCLC (10 cases) than SCC (6 cases). No significant differences were observed in other CT features between any other two groups. Iodine density and iodine ratio were statistically different among these three subtypes lung cancer (H=16.817,20.338,P<0.001). Iodine density of adenocarcinoma and SCC was (1.50±0.80) and (1.40± 0.40) mg/ml, respectively, higher than the (1.20±0.40) mg/ml for SCLC (P<0.01). Iodine ratio of adenocarcinoma and SCC was (16.10 ± 7.02)％and (15.05 ± 4.62)％, respectively, higher than the (11.55 ± 3.15)％ for SCLC (P<0.01). No significant difference was observed between adenocarcinoma and SCC. Accuracy of the model based on CT features was 69.1％, accuracy of the model based on CT features combined with DECT parameters was 80.9％. Conclusions Quantitative DECT metrics are different among adenocarcinoma, SCC and SCLC, when combined with morphological CT features, higher diagnostic accuracy can be achieved.

CT quantitative analysis and visual scores of pulmonary alveolar proteinosis and correlation with pulmonary function / 中华放射学杂志

Objective To investigate the evaluating the value of CT quantitative analysis and visual scores on pulmonary alveolar proteinosis (PAP). Methods Thirty one patients with PAP who underwent chest HRCT scans and pulmonary function tests(PFTs)between July 2014 and April 2016 in our hospital were collected and analyzed.HRCT mean lung density(MLD)was measured by syngo InSpace Lung Parenchyma Analysis.Using CT visual scores(HRCT score and RE score),two radiologists with three-years experience at least evaluated pulmonary lesions retrospectively. SPSS 21.0 statistical software was used to analyze the data. Spearman correlation analysis was used to evaluate the correlation between MLD, HRCT score and RE score.The correlation between MLD, HRCT score, RE score, the parameters of PFTs, and blood gas parameters were also analyzed by Spearman correlation analysis. Results There were correlations between MLD,HRCT score and RE score.The correlation coefficient among MLD,HRCT score and RE score were r=0.835 vs r=0.768 vs r=0.838 in baseline. The correlation coefficient among MLD, HRCT score and RE score were r=0.827 vs r=0.780 vs r=0.896 in follow-up. And there were also strong correlation between ΔMLD, ΔHRCTscore and ΔREscore. The correlation coefficient among ΔMLD, ΔHRCTscore and ΔREscore were r=0.599 vs r=0.651 vs r=0.867. There were significantly (P＜0.05) negative correlations among MLD, HRCT score, RE score and VA, DLCO in baseline and follow-up retrospectively. There were significantly (P≤0.001) negative correlations among the ΔMLD, ΔHRCTscore, ΔREscore and ΔVA, ΔDLCO.The correlation among MLD, HRCT score, RE score and DLCO was more significant than that of VA. The correlation among ΔMLD, ΔHRCTscore,ΔREscore and ΔDLCO was more significant than that of ΔVA.There were markedly(P＜0.05) negative correlations between MLD and PO2,and the correlation coefficient were r=-0.738 in baseline vs r=- 0.810 in follow-up. Conclusion The HRCT quantitative analysis and HRCT visual scores are feasible to evaluate PAP.

Synthesis of hydrogel polymer coated ZnO nanoparticles and their decontaminating effect against soman in vitro / 中国药理学与毒理学杂志

OBJECTIVE To evaluate the decontamination capability of hydrogel polymer coated ZnO nanoparticles (ZnO NP-gel) against soman. METHODS ZnO NP was synthetized using chemical precipitation method and modified with 4-pentenoic acid,and then polymerized with comonomers to obtain ZnO NP-gel. The transmission electron microscope (TEM), scanning electron microscope (SEM) and particle size instrument were used to observe the internal structure,micromorphology,particle size and zeta potential of these materials. An infrared spectroscope (IR) was used to analyze their chemical bond structure,while X-ray diffraction (XRD) was used to analyze the diffraction pattern.The content of soman was determined by benzidine chromogenic reaction. ZnO NP(1 g·L-1), ZnO NP-gel (1 g·L-1) and distilled water were mixed with soman(52.2 mg·L-1),stood for 30 min,and then filtered before filtrate was subcutaneously injected into mice (40 μL·g-1) to observe the symptoms of poisoning and death. RESULTS SEM and TEM showed that ZnO NP-gel had a block structure, the zeta potential of which was (-7.89 ± 0.04) mV. The results of IR indlicated that ZnO NP-gel had stronger absorption peaks at 754 and 618 cm-1, and XRD revealed that these materials had a sharp peak at 2θ=8.06738°. The decontamination efficiency of ZnO NP-gel was higher than that of ZnO NP group at the same concen?tration (n=3, P<0.05), and the time for decontamination of 50% soman was shortened by four times. The mice were injected subcutaneously with the soman solution treated with ZnO NP-gel, which caused no convulsion or death. CONCLUSION ZnO NP-gel can perform the double function of fast adsorption and catalysis of soman,and the decontamination ability of which could be improved through polymer modification.

High dose nanocrystallization of etoposide and its blood-brain barrier permeability in vitro / 中国药理学与毒理学杂志

OBJECTIVE To improve the poor water solubility and evaluating poor acitivity of etoposide (VP-16) by preparing VP-16 nanoparticle suspension (VP-16 NP) and its penetration through the blood-brain barrier (BBB).METHODS VP-16 NP was prepared with the anti-solution exchange method.The shape structure and diameter were observed with transmission electron microscopy (TEM) and scanning electron microscopy (SEM) and dynamic light scattering (DLS), respectively. The drug release profiles of the VP-16 powder and VP-16 NP were measured.The effect of VP-16 NP on the growth of KB cells was observed via MTT assay. In addition, primary brain microvascular endothelial cells from 1stto 2nd generation of SD rats at two weeks of age were used to construct an in vitro BBB model.The classic 4 h leak test,trans-epithelial electrical resistance (TEER) test and fluorescein disodium salt(FLU)perme?ability test were conducted to verify whether the in vitro BBB model was successfully established.RESULTS VP-16 NP was a solid sphere with a size of 140 nm detected by TEM,SEM and DLS.The cumulative release rate of VP-16 NP was 3 times that of VP-16 powder. The results of MTT colorimetric assay showed that VP-16 powder had no inhibitory effect on KB cells,while VP-16 NP could effectively inhibit KB cells. In the 4 h leakage experiment, the top and bottom chambers of the Transwell cell model could maintain a liquid surface distance of >0.5 cm,indicating that the in vitro BBB model was initially formed.The effective resistance value of the TEER experiment was 223 Ω·cm2,indicating that the in vitro BBB model was basically established. In FLU permeability experiments, the permeability coefficients were respectively (0.33±0.04)×10-3,(0.42±0.07)×10-3,and (0.52±0.06)×10-3cm·min-1at 15,30 and 60 min, indicating that the model had low permeability.The above three experiments suggested that the BBB in vitro model was successfully constructed. On this basis, the in vitro BBB model was used to evaluate the penetration of VP-16 NP at a permeability coefficient of (1.87±0.03)×10-3cm·min-1at 30 min,showing high permeability.VP-16 NP showed better penetration of BBB.CONCLUSION VP-16 NP is success?fully prepared,which increases the release rate of the drug,enhances the killing effect of the cells,and shows good penetration through the in vitro BBB model evaluation.

Effects of low level laser irradiation on the osteogenic capacity of sodium alginate/gelatin/human adipose-derived stem cells 3D bio-printing construct / 北京大学学报(医学版)

OBJECTIVE@#To explore the effects of low level laser irradiation (LLLI) on the osteogenic capacity of three-dimensional (3D) structure by 3D bio-printing construct used human adipose-derived stem cells (hASCs) as seed cells.@*METHODS@#Using hASCs as seed cells, we prepared sodium alginate/gelatin/hASCs 3D bio-printing construct, and divided them into four groups: PM (proliferative medium), PM+LLLI, OM (osteogenic medium) and OM+LLLI, and the total doses of LLLI was 4 J/cm². Immunofluorescence microscopy was used to observe the viability of the cells, and analyze the expression of the osteogenesis-related protein Runt-related transcription factor 2 (Runx2) and osteocalcin (OCN).@*RESULTS@#The 3D constructs obtained by printing were examined by microscope. The sizes of these 3D constructs were 10 mm×10 mm×1.5 mm. The wall thickness of the printed gelatin mold was approximately 1 mm, and the pores were round and had a diameter of about 700 μm. The cell viability of sodium alginate/gelatin/hASCs 3D bio-printing construct was high, and the difference among the four groups was not significant. On day 7, the expression of OCN from high to low was group OM+LLLI, PM+LLLI, OM and PM. There were significant differences among these groups (P<0.01), but there was no significant difference between group PM+LLLI and OM. On day 14, the expression of OCN in each group was higher than that on day 7, and there was no significant difference between group OM+LLLI and OM. The expression of Runx2 in group OM+LLLI was more than 90%, significantly higher than that in group OM (P<0.01). But the expression of Runx2 in group PM+LLLI and OM+LLLI were significantly lower than that in the non-irradiated groups. The expression of osteogenesis-related protein Runx2 and OCN were higher in OM groups than in PM groups. Furthermore, the irradiated groups were significantly higher than the non-irradiated groups.@*CONCLUSION@#LLLI does not affect the cell viability of sodium alginate/gelatin/hASCs 3D bio-printing construct, and may promote the osteogenic differentiation of hASCs.

Effect of Third-generation Dual-source CT Technology on Image Quality of Low-dose Chest CT / 中国医学科学院学报

Objective To evaluate the image quality and radiation dose of third-generation dual-source CT with tin filtration for spectral shaping and iterative reconstructions.Methods Thirty-five patients underwent low-dose CT (LDCT) for lung cancer screening on second-generation dual-source CT and follow-ups on third-generation dual-source CT. Image quality and radiation dose were compared between the two examinations.ResultsThe radiation dose of third-generation dual-source CT [dose-length product (DLP)(49.7±18.2)mGy·cm, effective dose (ED)(0.73±0.26)mSv] was lower than second-generation dual-source CT [DLP (86.37±13.44) mGy·cm, ED(1.20±0.42)mSv](t=6.01, P=0.000;t=6.57, P=0.000). The objective image noise of second-generation dual-source CT [(25.7±2.9)HU] was higher than that of third-generation dual-soure CT[(18.6±4.2)HU](t=5.24,P=0.000).The subjective image noise of second-generation dual-source CT [(4.60±0.49)scores] was significantly lower than that of third-generation dual-source CT [(4.80±0.40)scores] (t=4.15, P=0.000). Conclusion Chest CT for the detection of pulmonary nodules can be performed with third-generation dual-source CT that produces high image quality and low radiation dose when using a stellar infinity detector with spectral shaping.