Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 5 de 5
Filter
Add more filters










Database
Publication year range
1.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 2722-2725, 2021 11.
Article in English | MEDLINE | ID: mdl-34891813

ABSTRACT

Automatic analysis of fetal heart and related components in fetal echocardiography can help cardiologists to reach a diagnosis for Congenital Heart Disease (CHD). Previous studies mainly focused on cardiac chamber segmentation, while few researches deal with the cardiac component detection. In this paper, we tackle the task of simultaneous detection of the fetal heart and descending aorta in four-chamber view of fetal echocardiography, which is useful to analyze some kinds of CHD, such as left/right atrial isomerism, dextroversion of heart, etc. Several CNN-based object detection methods with different backbones are thoroughly evaluated, and finally, the Hybrid Task Cascade method with HRNet is selected as the detection method. Experiments on a fetal echocardiography dataset show that the method can achieve superior performance according to common-used evaluation metrics.Clinical relevance-This can be used to help the cardiologists to estimate the position of the fetal heart and the descending aorta, which is also useful to estimate the direction of the cardiac axis and apex and analyze some kinds of CHD, such as left/right atrial isomerism, dextroversion of heart, etc.


Subject(s)
Aorta, Thoracic , Heart Defects, Congenital , Aorta, Thoracic/diagnostic imaging , Echocardiography , Female , Fetal Heart/diagnostic imaging , Heart Defects, Congenital/diagnostic imaging , Humans , Pregnancy , Ultrasonography, Prenatal
2.
RSC Adv ; 10(46): 27775-27787, 2020 Jul 21.
Article in English | MEDLINE | ID: mdl-35516942

ABSTRACT

In this paper, the reoxidation behaviours of CrOOH and Cr(OH)3 are investigated as the major reduction products of Cr(vi). The atmosphere oxidation of Cr(iii) is studied in the environment of soil without manganese and hydrogen peroxide. The influence of temperature and pH value on the oxidation rate of Cr(iii) is examined by Experiment methods in details. According to the experimental results, the oxidation of Cr(iii) is promoted in the environment with high pH value, however, the oxidation process is stable with temperature. The oxidation process of CrOOH and Cr(OH)3 are theoretically researched by thermodynamic calculation and density functional theory (DFT) simulation. The results of DFT indicate that both CrOOH and Cr(OH)3 are oxidized during the chemical adsorption process of O2 in alkaline environment. With the transformation from Cr(iii) to Cr(vi), the Cr-O covalent bond forms in the adsorption process. The crystal structure difference between CrOOH and Cr(OH)3 leads to the different oxidation reaction between O2 and Cr(iii). The significant alteration of oxidation process in (110), (310), (321) crystal planes is also observed indicating the crystal orientation dependence. Based on the chemical reaction kinetics, the chemical equivalent constant K of CrOOH is higher than Cr(OH)3, illustrating higher chemical stability in air. In summary, both experimental study and theoretical analysis on the reoxidation phenomenon of Cr(iii) reduced from Cr(vi) in natural environment demonstrate that not only the external factors such as temperature and pH value but also the crystal structure of Cr(iii) compound have dramatic influence on the oxidation process.

3.
Nan Fang Yi Ke Da Xue Xue Bao ; 32(9): 1301-6, 2012 Sep.
Article in Chinese | MEDLINE | ID: mdl-22985569

ABSTRACT

OBJECTIVE: To investigate the effect of pretreatment with ulinastatin on liver regeneration and TNF-α/IL-6/STAT-3 signal pathway in rats after 70% hepatectomy combined with ischemia-reperfusion injury. METHODS: A total of 120 normal male SD rats weighing 230-280 g were randomized into 3 groups (n=40), namely simple partial hepatectomy (PH) group, partial hepatectomy with ischemia-reperfusion (PHIR) group, and ulinastatin group. All the rats received resection of the left and middle liver lobes. In PHIR group, the remnant right lobes were subjected to blood flow occlusion for 30 min; in UTI group, the rats were given 50 000 U/kg UTI intravenously prior to the occlusion, and in PH group, the blood flow was not occluded. At 1, 6, 12, 24, and 48 after the reperfusion, the remnant liver tissues were examined for regenerated liver weight, PCNA staining, TNF-α and IL-6, STAT-3, cyclin D1, and Cdk4 expressions. RESULTS: The regenerated liver weight and PCNA positivity rates were significantly higher in ulinastatin group than in PHIR group at 24 h and 48 h after the reperfusion (P<0.05). In ulinastatin group, the levels of TNF-α and IL-6 were significantly lower, and IL-6 level and the expressions of STAT-3, cyclin D1, and Cdk4 mRNA and cyclin D1 and Cdk4 proteins were significantly higher in ulinastatin group than in PHIR group at 24 h and 48 h (P<0.05). CONCLUSION: Ulinastatin can promote liver regeneration after major hepatectomy and ischemia-reperfusion injury, and the effect is possibly related with activation of IL-6/STAT-3 signal pathway, which promotes the synthesis of cyclin Dl-Cdk4 complex and hepatocyte proliferation.


Subject(s)
Glycoproteins/pharmacology , Liver Regeneration/drug effects , Reperfusion Injury/metabolism , Signal Transduction/drug effects , Animals , Cell Proliferation , Cyclin D1/metabolism , Cyclin-Dependent Kinase 4/metabolism , Hepatectomy/adverse effects , Hepatocytes/cytology , Hepatocytes/drug effects , Interleukin-6/metabolism , Liver/blood supply , Male , Rats , Rats, Sprague-Dawley , Reperfusion Injury/etiology , STAT3 Transcription Factor/metabolism , Tumor Necrosis Factor-alpha/metabolism
4.
Zhonghua Yi Xue Za Zhi ; 92(37): 2601-6, 2012 Oct 09.
Article in Chinese | MEDLINE | ID: mdl-23290059

ABSTRACT

OBJECTIVE: To explore the effects of ischemic postconditioning on the remnant liver regeneration under ischemic reperfusion after subtotal hepatectomy. METHODS: A total of 90 male SD rats weighting 230-280 g were randomly divided into 3 groups of simple subtotal hepatectomy (SH), ischemia reperfusion (IR) and ischemic postconditioning (IPO). The left and middle liver lobes were resected. And the remnant liver was treated as follows: blood flow was non-blocked in SH group, but blocked for 30 min in IR group, then reperfused. The IPO group was established by 30-30 s intermittent interruptions of blood flow thrice during the early phase of reperfusion. At 1, 6, 12, 24, 48 h respectively, the serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), hepatocyte growth factor (HGF) and the positive ratio of proliferating cell nuclear antigen (PCNA) were detected. Also the contents of adenosine triphosphate (ATP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP) were measured and the regenerated liver weight was calculated. RESULTS: The activities of ALT and AST in IPO group from 1 - 48 h were (138 ± 20), (340 ± 22), (770 ± 55), (389 ± 60), (113 ± 25) U/L and (247 ± 31), (509 ± 51), (972 ± 77), (955 ± 159), (222 ± 44) U/L respectively at each time point and they were significantly lower than those (294 ± 37), (560 ± 69), (1222 ± 162), (540 ± 40), (161 ± 15) U/L and (439 ± 34), (669 ± 94), (1347 ± 118), (1274 ± 223), (403 ± 68) U/L in IR group (P < 0.05); the regenerated liver weight (18.8 ± 3.2, 34.0 ± 3.5%) and positive cell ratio of PCNA (43.9 ± 2.7, 56.2 ± 4.0%) in IPO group at 24 and 48 h were respectively higher than those in IR group ((11.3 ± 2.9), (26.8 ± 2.5)% and (34.5 ± 2.8), (48.8 ± 1.8)%)(P < 0.05); The HGF levels ((261 ± 54) and (252 ± 103) pg/ml) at 24 and 48 h in IPO group were significantly higher than those ((99 ± 47) and (70 ± 19) pg/ml) in IR group (P < 0.05); the contents of ATP in hepatic tissue at 24 and 48 h in IPO group were (22.20 ± 3.6) and (12.87 ± 2.49) µg/g respectively. And they were significantly higher than those in IR group (P < 0.05), but lower than those in SH group (P < 0.05). CONCLUSION: Ischemic postconditioning improves the remnant liver regeneration under ischemic reperfusion after subtotal hepatectomy through its actions of stimulating HGF production and maintaining hepatic energy metabolism.


Subject(s)
Energy Metabolism , Ischemic Postconditioning , Liver Regeneration , Reperfusion Injury/metabolism , Animals , Hepatocyte Growth Factor/metabolism , Male , Rats , Rats, Sprague-Dawley
5.
Zhonghua Wai Ke Za Zhi ; 50(10): 909-13, 2012 Oct.
Article in Chinese | MEDLINE | ID: mdl-23302462

ABSTRACT

OBJECTIVE: To investigate the impact of the ischemic postconditioning on the tumor necrosis factor (TNF)-α/IL-6/signal transducers and activators of transcription (STAT)-3 signal pathway of liver regeneration. METHODS: Ninety healthy clean grade male Sprague-Dawley rats weighting 230 to 280 g were selected and assigned into three groups randomly: group I subtotal hepatectomy (SH), group II ischemia reperfusion (IR), group III ischemic postconditioning (IPO). The left and middle liver was resected, and the remnant liver was treated as followed: the blood flow was not blocked in SH group, but blocked 30 minutes in IR group, then reperfused; IPO groups received three cycles of 30 s-30 s intermittent interruptions of blood flow at onset of reperfusion. At 1, 6, 12, 24, 48 h after reperfusion, the serum TNF-α, IL-6 was detected and the mRNA of cyclinD1, Cdk4, STAT-3 was assayed by real-time PCR as well as the protein expression of cyclinD1 and Cdk4 by Western blot. RESULTS: Compared with SH group, the expression of IL-6 declined at each set time point in IR group (t = 5.076 to 8.334, P = 0.000), but the content of TNF-α increased in early stage (1 to 12 h) (t = 2.972 to 7.215, P = 0.000 - 0.014). The expression of STAT-3, cyclinD1 and Cdk4 mRNA and protein of cyclinD1 and Cdk4 at 24 and 48 h after reperfusion were lower in IR group than in SH group (t = 2.857 to 6.684, P = 0.000 to 0.017). However, there was a significant decrease in TNF-α from 1 to 12 h after reperfusion (t = 2.995 to 4.112, P = 0.002 to 0.017), but a significant increase in IL-6 in IPO group than in IR group (t = 2.458 to 3.543, P = 0.005 to 0.034). The expression of STAT-3, cyclinD1, Cdk4 mRNA and protein of cyclinD1 and Cdk4 at 24 and 48 h after reperfusion were all increased in IPO group in comparison with in IR group (t = 2.383 to 6.803, P = 0.000 to 0.038). CONCLUSIONS: The ischemic postconditioning could promote the remnant liver regeneration after subtotal hepatectomy with ischemia reperfusion injury. Its mechanism relates with the activation of the TNF-α/IL-6/STAT-3 signal pathway of and the cyclinD1-Cdk4 complex which enhances the proliferation of hepatocyte.


Subject(s)
Interleukin-6/metabolism , Ischemic Postconditioning , Liver Regeneration , Liver/metabolism , STAT3 Transcription Factor/metabolism , Tumor Necrosis Factor-alpha/metabolism , Animals , Cyclin D1/metabolism , Cyclin-Dependent Kinase 4/metabolism , Hepatectomy , Male , Rats , Rats, Sprague-Dawley , Signal Transduction
SELECTION OF CITATIONS
SEARCH DETAIL
...