1.Methods of analysis based on the signal characteristics of fMRI
International Journal of Biomedical Engineering 2006;0(01):-
The principles, traits, and proceedings of the data-driven methods including principal component analysis, independent component analysis and canonical analysis are summarized. And the aspects of the methods adapted to functional magnetic resonance images(fMRI) data are emphasized.
2.Application of Linear Models in Exploring the Relations between Behavior Data and Functional Magnetic Resonance Signals of Brain during Cognitive Task
Jiacheng LIU ; Jing BAI ; Qiyong GUO ; Dexuan ZHANG
Space Medicine & Medical Engineering 2006;0(04):-
Objective To build the linear models for exploring relations between behavior data and functional magnetic resonance image(fMRI) signals of brain during cognitive task and to validate whether it is reasonable.Methods The linear models of behavior data and fMRI signals were built,and the functional regions of brain were detected by tests of corresponding parameters.Experimental data of Stroop tasks were used to study the effects of the models by comparing with the results of SPM.Results The results of Stroop data showed that dorsal lateral prefrontal cortex(Brodmann 9/46),and superior frontal median cortex(Brodmann 8/9) were associated with response time of Stroop tasks,and accorded with SPM results and other reports.Conclusion The models can quantitatively analyze the relations of response time and fMRI signals,providing a new way to explore functional images of cognition.
3.A method to evaluate femoral bone mass in rats with CT numbers.
Liang PENG ; Hongkai WANG ; Jiacheng LIU ; Yu SHANG ; Jing BAI
Journal of Biomedical Engineering 2008;25(2):231-234
To develop a method of evaluating bone mass with CT numbers (Hounsfield unit, HU), volumetric mean of CT numbers (HUm) was defined to describe bone mass for the study of bone loss caused by microgravity. Ten femurs in the tail-suspended rats experiment were scanned by CT scanner. And the RUm of the intact, proximal, middle and distal femurs were obtained from these CT data. Then regressive analysis was performed between HUm and bone mineral density (BMD) measured by DXA in those regions. When HU threshold is equal to 400, the correlation between BMD and HUm of the intact femur is the best in all cases (R = 0.887, P <0.001), and the correlation between BMD and HUm of the proximal femur (R = 0.833, P <0.01) is better than those of the middle femur (R=0.683, P<0.05) and distal femur (R = 0.744, P<0.05). Volumetric mean of CT numbers has a good linear relationship with BMD; it can accurately describe bone mass and can be used to evaluate the results of the tail-suspended rats experiment.
Animals
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Bone Density
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Femur
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diagnostic imaging
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Radiographic Image Interpretation, Computer-Assisted
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Rats
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Tomography, X-Ray Computed
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methods
4.Effect of underdilated stent on the occurrence of hepatic encephalopathy after transjugular intrahepatic portosystemic shunt creation
Chaoyang WANG ; Bin XIONG ; Jiacheng LIU ; Chongtu YANG ; Shuguang JU ; Yaowei BAI ; Wei YAO ; Yingliang WANG
Chinese Journal of Internal Medicine 2022;61(5):537-542
Objective:To evaluate whether underdilated stent could reduce the occurrence of hepatic encephalopathy (HE) after transjugular intrahepatic portosystemic shunt (TIPS) creation.Methods:A total of 197 patients with decompensated liver cirrhosis, who had underwent TIPS creation at Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, were analyzed retrospectively, including 110 males and 87 females with age 25-79 (54±11) years old. Uncovered and covered stents with 8 mm diameter were implanted in all subjects, and then dilated by balloon catheters with 6 mm or 8 mm diameter. The patients were divided into two groups, including underdilated group (6 mm, n=105) and control group (8 mm, n=92).Kaplan-Meier curves were used to illustrate cumulative rate of HE, and the differences were assessed with the log-rank test. Multivariate analyses with a Cox regression model were conducted to explore the risk factors for HE. Results:During a median follow-up period of 29 (12-54) months, 16 (15.2%) patients developed HE in the underdilated group and 27 (29.3%) patients in the control group. There was a significant difference in the cumulative rate of HE ( P=0.014), but no statistical differences were found in terms of variceal rebleeding, shunt dysfunction and survival between the two groups ( P=0.608, P=0.659, P=0.968). In multivariated analysis, group assignment (underdilated vs. control, HR=0.291, 95% CI 0.125-0.674, P=0.004) was identified as an independent risk factor for HE after TIPS creation. Conclusion:Underdilated TIPS could reduced the risk of HE compared with completely dilated TIPS, with comparable risk of variceal rebleeding, shunt dysfunction and mortality. And it is worthy of applying this technique to a large sample of patients in clinical practice.
5.Ginsenoside rg3 reduces body weight by regulating fat content and browning in obese mice
Mu QIANQIAN ; Zuo JIACHENG ; Zhao DANDAN ; Zhou XIAOSHAN ; Hua JING ; Bai YING ; Mo FANGFANG ; Fang XIN ; Fu MIN ; Gao SIHUA
Journal of Traditional Chinese Medical Sciences 2021;8(1):65-71
Objective: To determine the effects of ginsenoside rg3 on the body weight of C57BL/6J obese mice and to investigate its underlying weight loss mechanisms with a focus on white fat browning-related factors. Methods: Eight-week-old C57BL/6J male mice were fed a high-fat diet for 12 successive weeks to construct the obese model. C57BL/6J male mice were fed a standard chow diet to construct normal control group. After 8 weeks of intervention with ginsenoside rg3, the food intake, body weight, body fat mass, blood sugar, and lipid profiles of the mice in each group were detected. Hematoxylin and eosin (HE) staining was used to observe the histological morphology of the adipose tissues. Real-time poly-merase chain reaction (RT-PCR) and Western blotting (WB) were applied to detect the gene and protein expression levels of peroxisome proliferators-activated receptor gama (PPARγ), Peroxisome proliferator-activated receptor-gamma coactivator -1alpha (PGC-1α), PR domain containing 16 (PRDM16), and uncoupling protein 1 (UCP-1).Results: Compared to normal control group mice, the body weight, food intake, body fat composition, and blood lipid levels of model group mice increased significantly. After 8 weeks of intervention with ginsenoside rg3, body weight, body fat composition, food intake, and blood lipid profiles decreased. HE staining showed that ginsenoside rg3 can improve white adipocyte hypertrophy to a certain extent. RT-PCR and WB demonstrated that ginsenoside rg3 can increase the mRNA and protein expression levels of PPARγ, PGC-1α, PRDM16, and UCP-1 in the adipose tissues of obese mice. Conclusion: The weight reduction effect of ginsenoside rg3 may be related to the promotion of white fat browning.
6.Direct reprogramming of fibroblasts into functional hepatocytes via CRISPRa activation of endogenous Gata4 and Foxa3
Jiacheng LI ; Ruopu LI ; Xue BAI ; Wenlong ZHANG ; Yu NIE ; Shengshou HU
Chinese Medical Journal 2024;137(11):1351-1359
Background::The ability to generate functional hepatocytes without relying on donor liver organs holds significant therapeutic promise in the fields of regenerative medicine and potential liver disease treatments. Clustered regularly interspaced short palindromic repeats (CRISPR) activator (CRISPRa) is a powerful tool that can conveniently and efficiently activate the expression of multiple endogenous genes simultaneously, providing a new strategy for cell fate determination. The main purpose of this study is to explore the feasibility of applying CRISPRa for hepatocyte reprogramming and its application in the treatment of mouse liver fibrosis.Method::The differentiation of mouse embryonic fibroblasts (MEFs) into functional induced hepatocyte-like cells (iHeps) was achieved by utilizing the CRISPRa synergistic activation mediator (SAM) system, which drove the combined expression of three endogenous transcription factors— Gata4, Foxa3, and Hnf1a—or alternatively, the expression of two transcription factors, Gata4 and Foxa3. In vivo, we injected adeno-associated virus serotype 6 (AAV6) carrying the CRISPRa SAM system into liver fibrotic Col1a1-Cre ER; Cas9 fl/fl mice, effectively activating the expression of endogenous Gata4 and Foxa3 in fibroblasts. The endogenous transcriptional activation of genes was confirmed using real-time quantitative polymerase chain reaction (RT-qPCR) and RNA-seq, and the morphology and characteristics of the induced hepatocytes were observed through microscopy. The level of hepatocyte reprogramming in vivo is detected by immunofluorescence staining, while the improvement of liver fibrosis is evaluated through Sirius red staining, alpha-smooth muscle actin (α-SMA) immunofluorescence staining, and blood alanine aminotransferase (ALT) examination. Results::Activation of only two factors, Gata4 and Foxa3, via CRISPRa was sufficient to successfully induce the transformation of MEFs into iHeps. These iHeps could be expanded in vitro and displayed functional characteristics similar to those of mature hepatocytes, such as drug metabolism and glycogen storage. Additionally, AAV6-based delivery of the CRISPRa SAM system effectively induced the hepatic reprogramming from fibroblasts in mice with live fibrosis. After 8 weeks of induction, the reprogrammed hepatocytes comprised 0.87% of the total hepatocyte population in the mice, significantly reducing liver fibrosis. Conclusion::CRISPRa-induced hepatocyte reprogramming may be a promising strategy for generating functional hepatocytes and treating liver fibrosis caused by hepatic diseases.
7.Analysis of multi spiral CT features of acute blunt or penetrating intestinal injury
Yinghe HUANG ; Xiongjun BAI ; Yingqi LI ; Jiacheng HUANG ; Junchu BAO ; Xucang DU ; Jiuping LIANG
Journal of Practical Radiology 2024;40(4):595-597,640
Objective To analyze the CT signs of acute blunt or penetrating intestinal injury,and to improve the diagnostic accuracy of multi spiral CT for intestinal injury.Methods The CT and clinical data of 63 patients with intestinal injury confirmed by clinical surgical exploration who underwent emergency CT scan were collected,and the CT findings and surgical findings were comparatively analyzed.Results There were 63 cases of intestinal injury,of which 26 cases were complicated with mesenteric injury.The direct CT signs of intestinal injury included intestinal wall thickening sign and intestinal discontinuity sign,which accounted for 64%(40/63)and 17%(10/63),respectively.The indirect CT signs of intestinal injury included intraperitoneal/retroperitoneal gas sign,intraperitoneal/retroperitoneal effusion sign,intramural air,and portal venous gas,which accounted for 72%(45/63),88%(55/63),7%(5/63)and 5%(3/63),respectively.Conclusion Recognizing the CT signs of intestinal injury,such as intestinal wall thickening sign,intestinal discontinuity sign,intraperitoneal/retroperitoneal gas sign,intraperitoneal/retroperitoneal effusion sign,intramural air,and portal venous gas can help to make the early and correct diagnosis of intestinal injury if combined with clinical practice.
8.Construction of EF-G knockdown strain of Mycobacterium smegmatis and drug resistance analysis.
Yuchang DI ; Jiacheng BAI ; Mingzhe CHI ; Weixing FAN ; Xuelian ZHANG
Chinese Journal of Biotechnology 2022;38(3):1050-1060
As the only translational factor that plays a critical role in two translational processes (elongation and ribosome regeneration), GTPase elongation factor G (EF-G) is a potential target for antimicrobial agents. Both Mycobacterium smegmatis and Mycobacterium tuberculosis have two EF-G homologous coding genes, MsmEFG1 (MSMEG_1400) and MsmEFG2 (MSMEG_6535), fusA1 (Rv0684) and fusA2 (Rv0120c), respectively. MsmEFG1 (MSMEG_1400) and fusA1 (Rv0684) were identified as essential genes for bacterial growth by gene mutation library and bioinformatic analysis. To investigate the biological function and characteristics of EF-G in mycobacterium, two induced EF-G knockdown strains (Msm-ΔEFG1(KD) and Msm-ΔEFG2(KD)) from Mycobacterium smegmatis were constructed by clustered regularly interspaced short palindromic repeats interference (CRISPRi) technique. EF-G2 knockdown had no effect on bacterial growth, while EF-G1 knockdown significantly retarded the growth of mycobacterium, weakened the film-forming ability, changed the colony morphology, and increased the length of mycobacterium. It was speculated that EF-G might be involved in the division of bacteria. Minimal inhibitory concentration assay showed that inhibition of EF-G1 expression enhanced the sensitivity of mycobacterium to rifampicin, isoniazid, erythromycin, fucidic acid, capreomycin and other antibacterial agents, suggesting that EF-G1 might be a potential target for screening anti-tuberculosis drugs in the future.
Antitubercular Agents/pharmacology*
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Bacterial Proteins/metabolism*
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Drug Resistance
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Mycobacterium smegmatis/metabolism*
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Peptide Elongation Factor G/pharmacology*
9.Impact of radiation dose to the immune system on prognosis for peripheral early-stage NSCLC treated with stereotactic body radiation therapy
Meigui LI ; Jiacheng LI ; Xiaofeng WANG ; Hui BAI ; Zhiyong YUAN ; Jun LIANG
Chinese Journal of Radiation Oncology 2024;33(5):405-412
Objective:To investigate the effects of radiation dose to the host immune system during radiotherapy on disease progression and survival in patients with peripheral early-stage non-small cell lung cancer (ES-NSCLC) receiving stereotactic body radiation therapy (SBRT).Methods:Clinical data of pathologically confirmed ES-NSCLC patients who were treated with SBRT at Tianjin Medical University Cancer Institute and Hospital between January 2007 and December 2020 were retrospectively analyzed. The prognostic significance of the estimated dose of radiation to immune cells (EDRIC) in ES-NSCLC patients undergoing SBRT was cited and validated. EDRIC was calculated using the model developed by Kong et al. and improved by Ladbury et al. Kaplan-Meier method and Cox proportional hazards regression were adopted to estimate cancer-specific survival (CSS), progression-free survival (PFS), local progression-free survival (LPFS), and distant metastasis-free survival (DMFS). Pearson's correlation was used to assess the correlation between variables. Results:The median prescription dose/fraction was 60 Gy/5 fractions (range: 48-60 Gy in 3-10 fractions). The median follow-up time was 52.17 (1.17-154.77) months. The median gross tumor volume (GTV) and EDRIC were 10.98 (0.91-120.34) cm 3 and 2.064 (0.426-6.015) Gy, respectively. Person's correlation analysis showed that GTV was positively correlated with EDRIC ( r=0.712, P<0.001). In multivariate analysis, EDRIC was an important prognostic variable of CSS and DMFS. Higher EDRIC was significantly associated with worse CSS ( HR=1.763, P=0.004) and DMFS ( HR=1.902, P=0.004). Compared to patients with EDRIC ≤ 1.56 Gy, those with EDRIC > 2.64 Gy and EDRIC between <2.06-2.64 Gy exhibited significantly lower CSS ( P<0.001, P=0.049). There were significant differences in DMFS among the groups divided by quartiles of EDRIC (compared to EDRIC ≤1.56 Gy, the P values were <0.001, 0.004, and 0.022 respectively). Conclusions:EDRIC is an important predictor of CSS and DMFS in ES-NSCLC patients treated with SBRT, suggesting that radiation dose to the immune system is a critical determinant of treatment outcomes. EDRIC can be used to quantify the effects of radiation therapy on the host immune system.