Objective To investigate the degradation characteristics of the large-scale brain functional networks during aging by functional magnetic resonance imaging measurement and explore its intrinsic mechanism.Methods 40 healthy subjects including 20 elderly persons [mean aged(72.4 ±4.6)years] and 18 young persons [mean aged(23.9± 1.8) years] were enrolled in this study.All subjects underwent functional MRI scanning at blood oxygenation level-dependent contrast resting state.Four canonical resting-state networks,including the default mode network (DMN),dorsal attention network (DAN),executive control network (ECN),salience network,and visual network,were extracted by the seed zone and double regression methods.The functional connectivities in these canonical networks were compared between the young and elderly persons.Results Compared with young persons,the elderly showed the distinct and disruptive alterations in the large-scale aging-related resting brain networks.The impairment of ECN was the most serious,followed by the impairment of DAN.The salience networks and DMN showed relatively limited functional connectivity disruption.The networks associated to higher-order brain functions were impaired,while the visual network,which served as a network related to low-order brain functions,had no significant change.Conclusions The aged brain in healthy subjects is characterized by organized change in networks,and the selective impairments of large-scale brain networks were more significant in the networks associated to higher-order brain functions as compared with the networks related to low-order brain functions.

Objective To evaluate the plasma level of miR-21 in hepatocellular carcinoma (HCC) patients and its clinical diagnostic significance .Methods Case-control study was used .The plasma level of miR-21 was measured by real-time quantitative PCR.The relative expressions of miR-21 were calculated. This study included 60 cases of patients with HCC , 71 patients with liver cirrhosis ( LC ) , 52 healthy volunteers ( HV) from January to June in 2014 in Henan Province People′s Hospital.The receiver operating characteristic ( ROC) curves were analyzed to determine the sensitivity and specificity of miR-21 expression levels in HCC diagnosis. Differences between groups were assessed by the t-test.Results Plasma microRNA-21 level in the 60 patients with hepatocellular carcinoma ( 2.6 ±1.1 ) was significantly higher than in patients with chronic hepatitis (1.6 ±0.9) and healthy volunteers (1.0 ±0.6) (t=5.322,P=0.004;t =8.349, P =0.000 3, respectively ) .Plasma microRNA-21 level in the HCC patients were positively correlated with tumor size and differentiation (tdif=3.366,P=0.019;tsize =3.490,P=0.012). ROC analysis of plasma microRNA-21 yielded an AUC of 0.796 with 70.0% sensitivity and 65.3%specificity when differentiating hepatocellular carcinoma from chronic hepatitis , and an AUC of 0.934 with 89.5% sensitivity and 81.8% specificity when differentiating hepatocellular carcinoma from healthy volunteers.Conclusion The plasma level of miR-21 in HCC patients has high specificity , and maybe help to diagnose of HCC.

The clinical characteristics and radiological data of 6 cases of sacral agenesis in one single family were analyzed and a literature review was performed.On magnetic resonance imaging (MRI),all of them presented with a partial absence of sacral vertebra,including associations with lumbar abnormalities (n =2) and sacral agenesis (n =2).One case presented with fourth/fifth lumbar vertebra bone fusion and fifth lumbar/first sacral vertebra bone fusion.On radiology,4 cases had concurrent scoliosis.None of them had tethered cord,diastematomyelia or meningocele.The understanding of sacral agenesis may be improved after reviewing and summarizing clinical features and radiological findings.

Objective To assess the value of a fibrin-targeted contrast agent (EP-2104R) for MR detection of thrombus, and to compare this modality with non-contrast-enhanced (NCE) MRI and Gd-DTPA injection at acute period after thrombus generation. Methods Thrombus was induced with external injury and stasis in 5 rabbits. MRI was performed before and after contrast agent injection at 6.0 h after injury, and the MRI findings were compared with that of histopathologically examinations. Results EP-2104R enhanced MRI accurately detected thrombus, which was superior to both NCE and Gd-DTPA injection (P<0.001). Gd-DTPA injection was not associated with improvement of thrombus detection. Conclusion Being a fibrin-targeted MR contrast agent for in vivo detection of acute thrombus, EP-2104R is superior to NCE MRI and Gd-DTPA injection.

Objective To compare the safety , surgery effects , pain scores of the close-distance-two-port video-assisted lobectomy and systematic dissection of the mediastinal nodes , and single-port video-assisted thora-coscopic surgery (VATS). Methods Between October 2012 and January 2015 in Peking University First Hospi-tal and Beijing Hospital , 269 patients who were going to be performed lobectomy and systematic lymph node dissection, were gathered and 205 patients were included in this study finally. Of the total, 122 patients were performed close-distance-two-port VATS , and 83 patients underwent single-port VATS. The clinical data were gathered, and statistically analyzed. Result In both groups, no severe postoperative complications or death oc-curred. No significant differences existed between the two groups in terms of intraoperative blood loss , duration and volume of chest tube drainage , postoperative pain score , hospital stay after surgery and hospitalization ex-penses (P > 0.05) but the data about operating time, number of dissected lymph nodes, complications(subcuta-neous emphysema , air-leak from the port of drainage tube and poor wound healing ) were significantly different (P < 0.05). Conclusions Compared with the single-port VATS, the method of close-distance-two-port video-as-sistant lobectomy and systematic dissection of the mediastinal nodes is safe and practicable with definite thera-peutic effect, less operation difficulty and complications.

Objective: To learn the sequence characteristics of C2-V4 of HIV-1 env genes and the epitope variation of representative broadly monoclonal neutralizing antibody in Fuxin, so as to provide evidence for the HIV-1 variation trend and the biological characteristics of V3 loop. Methods : The whole blood samples of 112 HIV-1 cases in Fuxin Health Service Center from 2018 to 2019 were collected and the DNA was extracted. The C2-V4 of env genes were amplified by nested-PCR and the PCR products were subjected to sequencing. The bioinformatics analysis was carried out using MEGA software, and the V3-tip motifs, co-receptors, net charge and characteristic amino acids were analyzed using HIV Database. Results: Totally 101 effective gene sequences were obtained, and 5 types of V3-tip motifs were found. Among them, 77 pieces of GPGQ ( 76.24% ) were found in CRF01_AE, CRF07_BC, CRF65_cpx and G subtypes; 19 pieces of GPGR ( 18.81% ) were found in CRF01_AE, CRF07_BC and B subtypes; 3 pieces of GPGH, 1 piece of GPGK and 1 piece of GPGA were only found in CRF01_ AE subtype. The co-receptor was mainly CCR5 ( 84, 83.17% ) . The net charge numbers of V3 loops in CRF01_ AE, CRF07_ BC, B, CRF65_cpx and G were 3.28±1.17, 3.22±0.92, 4.25±0.83, 2.50±0.50 and 3, respectively. The mutation rates of neutralizing antibodies binding b12 and VRC01 were 0-9.90%. The deletion rates of N-glycosylation sites of 295 and 332 were 18.81% and 14.85%, without the loss of both sites. Conclusions The HIV-1 strains in Fuxin from 2018 to 2019 are macrophage-tropic and non-syncytium-inducing, with GPGQ as the main type of V3-tip motif, CCR5 as the main co-receptor, slow replication and low ability to escape neutralizing antibodies.

Objective: To explore the effectiveness of machine learning algorithms in predicting non-suicidal self-injury (NSSI) behavior among college students, and to analyze the influencing factors of NSSI behavior, thus providing a reference for promoting psychological well-being. Methods: In December 2022, a stratified random cluster sampling method was used to select 835 college students from a university in Guizhou Province, China. The Adolescent Self-injury Scale, Family Function Assessment Scale, and Emotion Regulation Self-efficacy Scale were used to evaluate the participants. Demographic characteristics, family factors, and emotional factors were taken as independent variables, while the dependent variable was whether college students exhibited NSSI behavior. Machine learning algorithms, including Logistic regression, support vector machine (SVM), decision trees, algorithm gradient boosting trees, random forests, and AdaBoost, were used to construct predictive models. Results: The detection rate of NSSI behavior among the college students was 23.23% (194 individuals). The NSSI behavior group scored higher than the non-NSSI behavior group in total family function, emotional communication, egoism, and family rules ( t=3.02, 3.35 , 2.23,2.87, P <0.05). On the other hand, the non-NSSI behavior group scored higher than the NSSI behavior group in total emotion regulation selfefficacy, managing negative emotion self-efficacy, and expressing positive emotion self-efficacy ( t=-5.04, -5.48 , -2.43, P <0.05). The recall rates of random forests, SVM, Logistic regression, decision trees, algorithm gradient boosting trees, and AdaBoost were 84.3% , 90.6%, 73.4%, 87.5%, 95.3%, 89.0%, respectively. The F1 scores were 84.4%, 92.1%, 71.2 %, 79.4%, 91.7%, 89.1% , respectively. The respective precision rates were 84.4%, 93.5%, 69.1%, 72.7%, 88.4%, 89.1 %. The AUC scores were 0.845, 0.922, 0.706, 0.776, 0.915, and 0.891, respectively. Conclusion Compared to the algorithm gradient boosting tree, random forest, Logistic regression, and AdaBoost models, the SVM model has a better predictive effect on whether college students in Guizhou Province exhibits NSSI behavior. It is recommended to use an appropriate model to identify students at risk of NSSI behavior as early as possible and provide psychological crisis interventions to promote their mental health.

Objective:To analyze the clinical characteristics of elderly patients with acute interstitial pneumonia after thoracic surgery, and to provide evidence for the diagnosis and treatment of acute interstitial pneumonia after surgery.Methods:Data from 2578 elderly patients who had undergonethoracic surgery at Beijing Hospital from October 2014 to October 2021were collected.Five patients developed acute interstitial pneumonia after thoracic surgery.The diagnosis and treatment of the patients were analyzed and major relevant issues were discussed in combination with the literature.Results:Of the 5 patients aged from 60 to 74 years, including 4 men and 1 woman, 3 had idiopathic pulmonary interstitial fibrosis and 2 had Sjogren's syndrome with secondary pulmonary interstitial fibrosis.Preoperative chest CT images were characterized by sporadic interlobular septal thickening and ground-glass, reticular and linear opacities in both lungs.After surgery, all 5 patients presented unexplained and progressively aggravating dyspnea in 1~3 days and chest imaging showed newly emerged and more diffuse ground-glass, reticular and linear opacities in both lungs, in addition toprevious pulmonary interstitial fibrosis.Four patients were treated with glucocorticoids, and four underwent endotracheal intubation and mechanical ventilation.Two cases were treated successfully, 1 case improved after treatment but died after re-aggravation, and 2 cases died after treatment failure.Conclusions:Patients with pulmonary interstitial fibrosis after thoracic surgery may have progressive and aggravated dyspnea in the early postoperative period.Early CT imaging and pathogenic examinations will be helpful in differential diagnosis.Acute interstitial pneumonia often involves both lungs, with rapid progression and high mortality.Once the disease has progressed to respiratory failure, mechanical ventilation should be initiated as early as possible to improve organ function.Glucocorticoids should be used early with sufficient doses and lengths to prevent re-aggravation.

Objective: To summarize the clinical features, diagnosis and treatment of postoperative acute exacerbation of interstitial lung disease (ILD) after pneumonectomy. Methods: The clinical data of 4 patients with postoperative acute exacerbation of ILD after pneumonectomy admitted in Beijing Hospital from October 2014 to November 2015 were retrospectively analyzed and related literatures were reviewed. Results: Four patients were aged 60 to 74 years, including 3 males and 1 female, 2 of whom were idiopathic pulmonary fibrosis and 2 were connective tissue diseases related ILD. Chest high resolution computed tomography (HRCT) showed multiple lobular septal thickening, ground glass opacities, reticular shadow and strip shadow in both lungs. The patients developed acute dyspnea 2 to 3 days after pneumonectomy. In 2 cases, HRCT showed new patchy ground-glass opacities, reticular shadow and strip shadow in both lungs on the basis of preoperative pulmonary fibrosis. The sputum smear and culture showed no pulmonary infection in all 4 cases. Three patients were treated with glucocorticoids and 3 received mechanical ventilation with endotracheal intubation. One patient was successfully treated by early using adequate glucocorticoids, one patient improved after treatment but died after re-exacerbation, and the other two patients died after treatment failed. Conclusions Acute exacerbation of ILD after pneumonectomy often occurs in early postoperative period and it is characterized by progressive dyspnea. Chest CT and respiratory pathogen examination are helpful for early diagnosis. Postoperative acute exacerbation of ILD often lacks effective treatment, requires mechanical ventilation, and the prognosis is poor. Although glucocorticoids may be effective, re-exacerbation should be alert during treatment.

After kidney transplantation , timely detection of changes in transplanted kidney function may guide clinical managements and prevent or delay irreversible damage to transplanted kidney. Functional magnetic resonance imaging (fMRI) of transplanted kidney is a promising non-invasive technique of acquiring microstructural and microfunctional profiles of transplanted kidney. In recent years, various diffusion imaging modalities, arterial spin labeling (ASL) and blood oxygen level dependent-magnetic resonance imaging (BOLD-MRI) have gradually been applied for transplant kidneys. Transplant kidney function may be evaluated non-invasively from such microscopic perspectives as water molecule diffusion, blood flow perfusion and blood oxygen level. This review focused upon evaluating the renal function and identifying the causes of the renal function decline of transplanted kidney through various fMRI techniques and provide new rationales for clinical diagnosis.