Inhibitory Effect of CCK-8 on Methamphetamine-Induced Apoptosis / 法医学杂志

OBJECTIVES@#To investigate the inhibitory effect of cholecystokinin octapeptide (CCK-8) binding to cholecystokinin 2 receptor (CCK2R) on methamphetamine (METH)-induced neuronal apoptosis, and to explore the signal transduction mechanism of β-arrestin 2 in CCK-8 inhibiting METH-induced neuronal apoptosis.@*METHODS@#SH-SY5Y cell line was cultured, and HEK293-CCK1R and HEK293-CCK2R cell line were constructed by lentivirus transfection. Small interfering RNA (siRNA) was used to knockdown the expression of β-arrestin 2. Annexin Ⅴ-FITC/PI staining and flow cytometry were used to detect the apoptotic rate of cells, and Western blotting was used to detect the expression of apoptosis-related proteins.@*RESULTS@#The apoptosis of SH-SY5Y cells was induced by 1 mmol/L and 2 mmol/L METH treatment, the number of nuclear fragmentation and pyknotic cells was significantly increased, and the expression of apoptosis-related proteins Bax and cleaved caspase-3 were increased. CCK-8 pre-treatment at the dose of 0.1 mmol/L and 1 mmol/L significantly reversed METH-induced apoptosis in SH-SY5Y cells, and inhibited cell nuclear fragmentation, pyknosis and the changes of apoptosis-related proteins induced by METH. In lentivirus transfected HEK293-CCK1R and HEK293-CCK2R cells, the results revealed that CCK-8 had no significant effect on METH-induced changes of apoptosis-related proteins in HEK293-CCK1R cells, but it could inhibit the expression level of apoptosis-related proteins in HEK293-CCK2R cells induced by METH. The inhibitory effect of CCK-8 on METH-induced apoptosis was blocked by the knockdown of β-arrestin 2 expression in SH-SY5Y cells.@*CONCLUSIONS@#CCK-8 can bind to CCK2R and exert an inhibitory effect on METH-induced apoptosis by activating the β-arrestin 2 signal.

Preliminary evaluation of coronary fractional flow reserve derived from CT based on tracer-kinetics principle / 中华放射学杂志

Objective:To evaluate the feasibility and diagnostic efficacy of the coronary fractional flow reserve derived from CT (CT-FFR) measurement method based on tracer pharmacokinetic principle.Methods:A total of 130 patients (159 coronary artery vessels) who were admitted to Beijing Anzhen Hospital from January 2015 to March 2019 were included in this study retrospectively. All patients had completed coronary CT angiography (CCTA) and invasive coronary angiography with invasive FFR. Subjective assessment of stenosis degree was performed on CCTA images and non-invasive FFR measurement was performed by using a tracer-kinetics based on CT-FFR measurement method. The Bland-Altman method was used to evaluate the diagnostic consistency of the two methods. Compared with the invasive FFR results, the sensitivity, specificity, positive predictive value, negative predictive value, and area under the ROC curve (AUC) of tracer-kinetics based on CT-FFR results for the diagnosis of coronary ischemic lesions were evaluated. All cases were divided into two heart rate groups:>65 bpm and ≤65 bpm. The diagnostic efficacy of tracer-kinetics based on CT-FFR in different heart rate groups was evaluated. χ 2 test and DeLong test were used to compare diagnostic performance in different evaluation methods and heart rate groups. Logistic regression analysis was used to evaluate the impact of factors such as heart rate, image thickness, image enhancement, and noise on the accuracy of diagnosis. Results:Bland-Altman analysis showed that the average difference between the two methods was -0.01. (-0.11-0.10). Compared with invasive FFR results, the tracer-kinetics based on CT-FFR method had a diagnostic sensitivity of 92.4%, specificity of 82.1%, positive predictive value of 87.6%, negative predictive value of 88.7%, and the area under ROC curve (AUC) value was 0.94. Compared with the diagnostic efficacy of luminal stenosis evaluated based on CCTA images, the difference was significantly statistical ( P<0.05). The diagnostic performance of CT-FFR had no statistically significant difference between the two heart rate groups. Factors such as heart rate, image thickness, image enhancement, and noise had no significant effect on the diagnostic accuracy of the tracer-kinetics based on CT-FFR method. Conclusions:The tracer-kinetics based on CT-FFR method may quickly complete the non-invasive FFR measurement on CCTA images with image quality that meets the needs of clinical diagnosis. It has a good diagnostic performance in the diagnosis of coronary ischemic lesions even for those cases with a faster heart rate. The diagnostic accuracy of tracer-kinetics based on CT-FFR method is not significantly affected by factors such as heart rate, image thickness, image enhancement, and image noise.

Estimation on Formation Time of Thrombus / 法医学杂志

OBJECTIVES@#To observe the changes of the formation time of venous thrombus in rats, and to provide new ideas and methods for the estimation on thrombus formation time of the forensic cases died from thrombosis.@*METHODS@#Totally 80 rats were randomly divided into 10 groups （0 h, 3 h, 6 h, 12 h, 1 d, 3 d, 1 week, 2 weeks, 3 weeks and 4 weeks after operation）. A vein thrombosis model was established by the "narrow" method. The processes of thrombosis, organization, recanalization and the features of change on hemosiderin and calcium salt were observed by HE stain, Perls stain and Von Kossa stain. The expression changes of CD61, α-SMA and CD34 were observed by immunohistochemical staining technique.@*RESULTS@#Platelets adhered to the exposed blood vessel intima 3 h after operation, and platelet trabeculae were formed by the repeated accumulation of platelets 1 d after operation. The thrombus organization formed through the fibroblasts from vessel wall that grew into the interior of the thrombus 3 d after operation. Endothelial cells covered the surface of thrombus and then the new blood vessels were reformed, and the vessels were reconstructed. The expression of CD61 upregulated at the stages of the thrombus formation （3 h） and thrombus reformation （4 weeks）, and reached the peak 1 d after thrombus formation. The release of hemosiderin and the initial expression of α-SMA were detected 3 d later. Calcium deposit and expression of CD34 were observed 1 week later.@*CONCLUSIONS@#The hemosiderin, calcium salt, CD61, α-SMA and CD34 show time-dependent changing characteristics, which is expected to provide a reference for the estimation on thrombus formation time of the forensic cases died from thrombosis.

Cardiac Ultrastructure and Changes of HSP70 and HIF-1α Expression in Electric Shock Death Rats / 法医学杂志

OBJECTIVE@#To observe cardiac ultrastructure and the expression of heat shock protein 70 (HSP70) and hypoxia inducible factor-lα (HIF-lα) in electric shock death rats and to explore the application of these indexes as the basis of medical identification in electric shock death.@*METHODS@#Seventy-two SD rats were randomly divided into electric shock death group, postmortem electric shock group and the control group. The changes of myocardial ultrastructure were observed by transmission electron microscope, and the expressions of myocardial HSP70 and HIF-1α were observed by immunohistochemical technology.@*RESULTS@#Myocardial myofibril fracture, mitochondrial cristae and membrane dissolution, and disordered arrangement of Z lines and M lines were observed in electric shock rats. HSP70 and HIF-lα were strong positive expressions in the electric shock death group, significantly compared with the control and postmortem electric shock groups (P < 0.05).@*CONCLUSION@#The expressions of HSP70 and HIF-lα were obviously increased in electric shock death group, which may be used as the diagnostic indicator of electric shock death.

Study on isolation of endophytic fungi from Sinopodophyllum hexandrum and their antimicrobial activities / 中草药

Objective: To explore the resource diversity of endophytic fungi from the endangered Sinopodophyllum hexandrum and its antimicrobial activity. Methods: The endophytic fungi were isolated by tissue block method. Five pathogenic fungi and four bacteria were used as indicators to test the antimicrobial activity by agar plate antagonistic action and improved agar gel diffusion methods. Results: The results indicated that 49 endophytic fungi strains were isolated from the roots, stems, and leaves of S. hexandrum, the most was from the roots (22), then from the stems (18), but the least was from the leaves (19); The isolated strains attributed to nine genera, three families, and two orders, and Fusidium sp. was the dominant genera based on morphological characters; For the isolated strains, 22 of them expressed the inhibition to one or more pathogenic fungi, amounting to 44.8% of the total isolates, and eight strains were found to have significant inhibition against two or more pathogenic fungi, making up 16.3% of the total isolated strains, and three isolated endophytic fungal strains showed the evident inhibition against four or more indicating pathogenic fungi, and the two isolated strains showed the obvious antibacterial activity against the two indicating bacteria. Conclusion: The endophytic fungi isolated from S. hexandrum have the diversity and evident inhibition against exterior fungi, active strains belong to the fungi of Aspergillus sp., Hormodendrum sp., and Fusidium sp., respectively, and its research and development are of ecological and economic significances.

Stercoral colonic diverticulum perforation with jejunal diverticulitis mimicking upper gastrointestinal perforation / 中华医学杂志(英文版)

Stercoral perforation of the colon is an unusual pathological condition with fewer than 150 cases reported in the literature to date. We present a case of stercoral colonic perforation mimicking upper gastrointestinal perforation, which was diagnosed by computed tomography preoperatively. However, at laparotomy, stercoral colonic diverticulum perforation with jejunal diverticulitis became the most appropriate diagnosis.

Dual-energy CT angiography plus CT perfusion-diagnostic value in coronary artery disease: initial experience / 中华放射学杂志

Objective To evaluate the combination of dual-energy CT angiography (DE-CTA) and dual-energy CT peffusion (DE-CTP) in the diagnosis of coronary artery disease. Methods Thirty-one patients with angina pectoris were examined using dual-source dual energy CT and conventional coronary angiography. For DE-CTA, we used a contrast-enhanced ECG-gated coronary scan protocol with energy levels of two tube detector arrays at 140 and 100 kVp. Two kinds of acquired images were fused for the CT angiogram and further calculated to construct a perfusion map (Siemens DE Heart PBV). The compared the following results: DE-CTA vs. CA, DE-CTP vs. CA to assess the sensitivity and specificity, and further compared DE-CTA plus DE-CTP with CA. Results DECT obtained diagnostic image quality in 28 patients.DE-CTA detected 41/112 arterial stenosis. Using CA as a reference, the sensitivity of DE-CTA was 81%(38/47), specificity was 95% (62/65), positive predictive value was 92% (38/41), negative predictive value was 87% (62/71), and accuracy was 89% (100/112). DE-CTP detected 46 perfusion defects in artery territories. Using CA as a reference, the sensitivity of DE-CTP was 76% ( 36/47), specificity was 85% (55/65), positive predictive value was 78% (36/46), negative predictive value was 83% (55/66),and accuracy was 81% (91/112). DE-CTA plus DE-CTP diagnosed 52 arteries stenosis. Using CA as a reference, combination of DE-CTA and DE-CTP gave sensitivity of 95% ( 45/47 ), specificity of 89%(58/65) , NPV of 97% (58/60), and accuracy of 92% (103/112). Conclusions DECT can provide perfusion blood volume information as well as vessel pathology in one scan. DECT can provide comprehensive diagnosis and improve diagnosis of CAD.

Multiple center study about the reliability of the low-dose dual-source CT coronary angiography in the step-and-shoot mode / 中华放射学杂志

Objective To investigate the accuracy of low-dose dual-source computed tomography (DSCT) coronary angiography in the step-and-shoot (SAS) mode for the diagnosis of coronary artery stenosis in comparison with conventional coronary angingraphy (CCA).Methods Prospective multiple-center study, 46 patients[mean age(58±9) years;bedy mass index(BMI) (25±3) kg/m2]underwent both DSCT in the SAS mode and CCA within 14 days.The inclusion criteria for contrast-enhanced CT: (1) heart rate less than 65 times/rain (bpm).(2) regular sinus rhythm, heart rate fluctuations within the range of 6 bpm. (3) holding breath well, breath-hold time is about 12-15 s.The exclusion criteria:(1) allergy to iodinecontaining contrast medium, nephropathy (serum creatinine level 120 μmol/L), heart failure and serious arrhythmias.(2) patients with coronary stents or bypass grafts.(3) heart rate can not be controlled very well (4)the patient could not take nitroglycerin.(5)BMI 30 kg/m2.(6) other heart disease: carcliomyopathy, valvular disease etc.Sensitivity, specificity, negative (NPV) and positive predictive value (PPV) were determined with CCA as standard of reference.The Kappa value between the two modalities and the two observers was calculated.Radiation dose values were measured.Results Mean heart rate during scanning was (61±6)bpm.99.19% (614/619) coronary segments were depicted with a diagnostic image quality. The vessel-based sensitivity, specificity, PPV, and NPV for the diagnosis of coronary artery stenosis were 96.2% (75/78), 88.2% (60/68), 90.4% (75/83), and 95.2% (60/63), respectively.The Kappa value between the two modalities was 0.848 (P=0.000).The mean effective dose of the SAS-CTCA was (2.95± 0.96) rosy(1.26-4.32 mSy).Conclusion In selected patients, DSCT coronary angiography in the SAS mode have good image quality, which allows for the accurate diagnosis of coronary stenosis at a low radiation dose.