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S L Jiang

Publications and source records attributed to S L Jiang.

18 recordsLinked to original sources
PubMed2001

Effects of window and threshold levels on the accuracy of three-dimensional rendering techniques in coronary artery electron-beam CT angiography.

RATIONALE AND OBJECTIVES: The authors performed this study to evaluate the effect of window level and gray-scale threshold on the demonstration of coronary artery lumina at three-dimensional electron-beam computed tomographic (CT) angiography. MATERIALS AND METHODS: Forty-four coronary artery branches in postmortem pigs were evaluated with electron-beam CT angiography, and the findings were compared with those from conventional angiography. Images from electron-beam CT angiography were reconstructed with maximal intensity projection (MIP), multiplanar reformation (MPR), and shaded-surface display (SSD). Four categories of window level and gray-scale threshold were evaluated. RESULTS: Three-dimensional electron-beam CT angiography accurately depicted the luminal diameters of the coronary arteries compared with conventional angiography (r = 0.83-0.90, P < .0001). The length of lumina visualized at electron-beam CT angiography was significantly shorter than that visualized with conventional angiography (P < .001). The use of MPR enabled visualization of longer segments of coronary arteries than did the use of MIP or SSD (P < .05). The higher the window level and gray-scale threshold used, the smaller the coronary luminal diameters measured (P < .05). The most accurate window level and gray-scale threshold (82.6 HU +/- 29.8 and 89.5 HU +/- 29.7, respectively) were found to correspond to the attenuation of the lumina (275.8 HU +/- 58.8). Results of simple linear regression showed a strong correlation between luminal attenuation and window level (r = 0.89, P < .0001) or gray-scale threshold (r = 0.95, P < .0001). CONCLUSION: Electron-beam CT angiography shows promise in the visualization of coronary artery lumina. For accurate display of lumina, a proper window level and gray-scale threshold for three-dimensional rendering techniques should be determined and used on the basis of the attenuation of the target vessel.

Animals↗
PubMed2000

[Study on the characteristics and applications of a new hydrophobic interaction chromatographic packing using chitosan as support].

Based on chitosan, by using valeraldehyd as ligand, a new hydrophobic interaction chromatographic (HIC) packing material was prepared by an improved method. The effects of salt concentration, temperature, pH on the adsorption of bovine serum albumin(BSA) were investigated. The results showed that the adsorption behavior of protein by packing material is in agree with the theory of hydrophobic interaction. The alpha-amylase could be separated by HIC with high recovery of enzymatic activity.

Chitin↗
PubMed1996

C-reactive protein and serum amyloid A mRNA stability following induction by cytokines.

We determined the effects of cytokine withdrawal on C-reactive protein (CRP) and serum amyloid A (SAA) mRNA abundance in Hep3B cells following 24 h of preinduction with interleukin 6 plus interleukin 1 beta. After cytokine withdrawal, CRP transcription rate rapidly fell to undetectable levels and mRNA levels fell with a half-disappearance time of about 2.5 h. In view of the relatively small amount of CRP transcription occurring at this time, it is likely that this value closely reflects the actual half-life of CRP mRNA. In contrast, substantial SAA transcription continued for at least 8 h, while SAA mRNA fell with a half-disappearance time of about 8.5 h. It is not possible, under these conditions, to determine SAA mRNA half-life, but it clearly was no greater than 8.5 h. Both Actinomycin D (ActD) and cycloheximide enhanced the stability of SAA mRNA, strongly suggesting that SAA mRNA degradation requires synthesis of a short-lived protein. CRP mRNA stability was also enhanced by ActD, but cycloheximide did not have a protracted stabilizing effect, suggesting complex regulatory processes. These studies provide insight into the stability of CRP and SAA mRNA following induction with [IL-6 + IL-1 beta] and into the mechanisms regulating their degradation.

Blotting, Northern↗
PubMed1995

The effect of interleukin-1 on C-reactive protein expression in Hep3B cells is exerted at the transcriptional level.

The combination of interleukin 6 (IL-6) and interleukin 1 (IL-1) synergistically induces the human acute-phase reactant, C-reactive protein (CRP) in Hep3B cells. While previous studies have indicated that IL-6 induces transcription of CRP, the mode of action of IL-1 has not been clearly defined. It has been suggested that the effect of IL-1 might be post-transcriptional, exerted through the 5'-untranslated region (5'-UTR). To evaluate the role of IL-1 in CRP gene expression, we studied the effects of interleukin-6 (IL-6) and interleukin-1 beta (IL-1 beta) on both the endogenous CRP gene and on transfected CRP-CAT constructs in Hep3B cells. In kinetic studies of the endogenous CRP gene, IL-1 beta alone had no effect on CRP mRNA levels, but when added to IL-6, synergistically enhanced both CRP mRNA levels and transcription, as determined by Northern-blot analyses and nuclear run-on studies. IL-6 alone and the combination of [IL-1 beta + IL-6] each induced increases in mRNA levels roughly comparable with observed increases in transcription. These findings indicate that the effect of IL-1 beta on CRP expression is exerted largely at the transcriptional level in this system. This conclusion was confirmed by studies in Hep3B cells transiently transfected with CRP-CAT constructs, each containing 157 bp of the CRP 5'-flanking region but differing in the length of the 5'-UTR from 104 bp to 3 bp. All constructs responded in the same way; IL-6, but not IL-1 beta, induced significant chloramphenicol acetyltransferase (CAT) expression which was synergistically enhanced 2- to 3-fold by IL-1 beta. These results indicate that IL-1 beta stimulates transcriptional events in the presence of IL-6 and that the upstream 157 bases of the CRP promoter contain elements capable of both IL-6 induction and the synergistic effect of IL-1 beta on transcription.

C-Reactive Protein↗
PubMed1995

Induction of human serum amyloid A in Hep 3B cells by IL-6 and IL-1 beta involves both transcriptional and post-transcriptional mechanisms.

Previous studies of murine serum amyloid A (SAA) regulation during inflammatory states or following exposure to macrophage-conditioned medium have raised the possibility that both post-transcriptional and transcriptional mechanisms participate in induction of this family of proteins. Since IL-6 and IL-1 have been shown to induce SAA in human hepatoma cell lines, we explored the possibility that these cytokines might induce human SAA through post-transcriptional as well as transcriptional mechanisms. In kinetic studies, we found that continuous exposure of Hep 3B cells to either IL-6 or IL-1 beta alone caused only minimal increases in SAA mRNA and marginal increases in transcription (as measured by nuclear runon). In contrast, the combination of these cytokines led to a 23-fold increase in transcription, maximal at 12 h, with continuing increase in mRNA, achieving levels more than 1,000-fold greater than baseline by 72 h. This massive disparity between increases in mRNA and in transcription rate strongly supports the participation of post-transcriptional mechanisms in SAA induction by (IL-6 + IL-1 beta), whereas the lag between peaks of transcription and mRNA abundance reflects a relatively slow degradation rate of SAA mRNA. As observed by other workers, mean size of SAA mRNA decreased progressively over the course of incubation. Simultaneous kinetic studies of complement factors B and C3, haptoglobin, and alpha-1 protease inhibitor revealed several different patterns of response to IL-6 and IL-1 beta.

Blotting, Northern↗
PubMed1995

Kinetic modeling and mathematical analysis indicate that acute phase gene expression in Hep 3B cells is regulated by both transcriptional and posttranscriptional mechanisms.

To evaluate the possible role of posttranscriptional mechanisms in the acute phase response, we determined the kinetics of transcription (by nuclear run-on assay) and mRNA accumulation of five human acute phase genes in Hep 3B cells incubated with conditioned medium from LPS-stimulated monocytes. Increase in mRNA accumulation was comparable to increase in transcription rate for fibrinogen-alpha and alpha-1 protease inhibitor, suggesting largely transcriptional regulation. In contrast, mRNA accumulation was about 10-20-fold greater than transcriptional increase for serum amyloid A, C3, and factor B, suggesting participation of posttranscriptional mechanisms. Since finding a disparity between the magnitudes of increase in mRNA and transcription does not definitively establish involvement of posttranscriptional mechanisms, we subjected our data to modeling studies and dynamic mathematical analysis to evaluate this possibility more rigorously. In modeling studies, accumulation curves resembling those observed for these three mRNAs could be generated from the nuclear run-on results only if posttranscriptional regulation was assumed. Dynamic mathematical analysis of relative transcription rates and relative mRNA abundance also strongly supported participation of posttranscriptional mechanisms. These observations suggest that posttranscriptional regulation plays a substantial role in induction of some, but not all acute phase proteins.

Acute-Phase Reaction↗
PubMed1993

Applicability of Orem's conceptual framework: a cross-cultural point of view.

Orem's conceptual framework for nursing is analysed and evaluated for its applicability in Chinese nursing practice. The appropriateness of Orem's nursing theory for application in Chinese nursing practice is determined through an examination of its completeness, compatibility, practicality and feasibility. Some insights and recommendations are offered for consideration.

Attitude to Health↗
PubMed1991

Effect of combinations of cytokines and hormones on synthesis of serum amyloid A and C-reactive protein in Hep 3B cells.

We have previously shown that induction of synthesis of the two major human acute phase proteins, serum amyloid A (SAA) and C-reactive protein (CRP), can be accomplished in the human hepatoma cell line Hep 3B, in the presence of dexamethasone, either by conditioned medium from LPS-stimulated monocytes or by the combination of IL-6 and IL-1. Neither of these cytokines alone caused significant induction of either SAA or CRP. In the present study we extended our earlier observations by evaluating the role of dexamethasone, the effect of different concentrations of IL-6 and IL-1 alpha in combination, and the possible role of TNF-alpha in regulating synthesis of SAA and CRP. Dexamethasone alone had no effect on induction of SAA or CRP. Incubation of Hep 3B cells with conditioned medium from LPS-stimulated monocytes, in the absence of dexamethasone, led to modest induction of SAA or CRP, but addition of dexamethasone potentiated this response in a dose-dependent manner. Similar results were obtained for the effect of dexamethasone on the induction of SAA by IL-6 plus IL-1 alpha. Checkerboard titration of IL-6 and IL-1 alpha revealed that increases in concentration of either cytokine led to dose-related increases in synthesis of both SAA and CRP as long as a minimal amount of the other cytokine was present. TNF-alpha alone had no significant effect on synthesis of either SAA or CRP, but the combination of IL-6 plus TNF-alpha led to substantial induction of SAA. This combination was less effective than the combination of IL-6 plus IL-1 alpha. No detectable effect of IL-6 plus TNF-alpha was observed on CRP synthesis. Both combinations of cytokines, IL-6 plus IL-1 alpha, and IL-6 plus TNF-alpha, caused increased SAA mRNA accumulation that roughly paralleled increase in synthesis. These data indicate that IL-6, IL-1 alpha, TNF-alpha, and dexamethasone in various combinations are all capable of influencing synthesis of SAA in Hep 3B cells, whereas only IL-6, IL-1 alpha, and dexamethasone can influence CRP synthesis.

C-Reactive Protein↗
PubMed1989

[Coronary arteriography in coronary heart diseases with angina pectoris (an analysis of 55 cases)].

A retrospective study of the coronary arteriographic findings in 55 cases with angina pectoris, 10 spontaneous angina and 45 effort angina (unstable angina 21, stable 24) was presented in the present article. Among the 10 cases with spontaneous angina, 8 showed normal coronary arteries, 2 with double vessel disease. In the 45 cases with effort angina, single and multiple vessel disease was found in 9/45 (20%) and 33/45 (73.3%) respectively, the remaining 3/45 (6.7%) were normal. There was no significant difference in severity and distribution of coronary atherosclerotic lesion (P greater than 0.05) in the two subgroups of unstable and stable angina. However in 3 out of 21 cases (14%) with unstable angina total occlusion of coronary arteries was found suggesting the presence of intracoronary thrombus. Triple vessel disease or/and left main coronary artery lesion was observed more frequently in cases with unstable angina (13/21, 61.9%) than in cases with stable angina (10/24, 41.7%).

Adult↗
PubMedDate not supplied

Coronary artery stenoses: a phantom study using contrast enhanced three-dimensional electron beam tomography.

This paper evaluated the accuracy of electron beam tomographic angiography (EBA) with conventional coronary arteriography (CCA) using four graded artificial stenoses in a postmortem swine coronary phantom model. The sensitivity, specificity, and accuracy of EBA for diagnosing significant stenosis (> or =50% stenosis) were 94.3%, 96.7%, and 95.8%, respectively. The diagnostic accuracy of EBA had no significant difference with CCA (chi(2)=0.0162; P>.05). EBA three-dimensional (3D) procedures had high interobserver reproducibility (k=.92-.95, P>.05). Maximum intensity projection (MIP) was the most sensitive and curved planar reformation (CPR) was the most accurate 3D procedure for quantitatively identifying coronary stenosis. EBA yields promising results concerning the visualization of coronary artery stenosis with high accuracy for stenoses >50%.

Animals↗