Biomedical subjects

Rui Liu

Publications and source records attributed to Rui Liu.

65 records · Page 4Linked to original sources

PubMed2003

Association between fasting and postprandial triglyceride levels and carotid intima-media thickness in type 2 diabetes patients.

OBJECTIVE: To investigate the association of fasting and postpiandial triglyceride with carotid intima-media thickness among type 2 diabetic patients in southeast China. METHODS: A total of 78 type 2 diabetic patients from southeast China were recruited. All the subjects underwent a standardized mixed-meal test (SMMT) and an oral glucose tolerance test. Carotid intima-media thickness (IMT) was measured by color doppler ultrasound examination. RESULTS: Postprandial triglyceride (PTG) after SMMT increased significantly in type 2 diabetic patients. The carotid IMT in patients with postprandial hypertriglyceridemia was significantly greater than that in patients with postprandial normal-triglyceridemia (0.90 mm vs 0.81 mm, P < 0.05), which remained significant after adjustment for fasting TG and HDL-c levels, and the IMT in patients with fasting hypertriglyceridemia only had tendency to increase compared to patients with fasting normal-triglyceridemia (0.87 mm vs 0.84 mm, P > 0.05). CONCLUSION: The results suggest that postprandial hypertriglyceridemia may be an independent risk factor of early atherosclerosis in type 2 diabetes.

Carotid Arteries↗

PubMed2003

[Inducible expression of reconstructed human caspase-6 gene in Hela cells].

AIM: To observe the pro-apoptotic effect of RCasp-6 gene in Hela cells. METHODS: RCasp-6 gene was amplified by PCR and cloned into the pIND vector. Hela cells were transfected with pIND-RCasp-6 and then inducced with ecdyson analogue. Expression of target gene was detected by immunocytochemical staining. Changes of the morphology and growth of Hela cells subjected to transfection of target gene were observed by HE staining and viable cell counting. RESULTS: RCasp-6 gene was cloned by PCR and its eukaryotic expression vector was successfully reconstructed. Expression of RCasp-6 gene in the transfected Hela cells leads to the morphological changes of the cells. Many of the transfected Hela cells shrunk and some cells were died. CONCLUSION: The expression of reconstructed human caspase-6 gene can efficiently accelerate death of Hela cells.

Apoptosis↗

PubMed2002

[Computer-assisted planning for neurosurgery: a clinical study].

OBJECTIVE: To investigate the clinical effect of computer-assisted planning for neurosurgery (CAPN). METHODS: 100 groups of directional targets were randomly sampled. The targets' directional three-dimension coordinates measured with CAPN and those measured by traditional reading device were analyzed statistically. CAPN was actualized in 137 cases of stereotactic operation. RESULTS: The data measured with CAPN and those with traditional reading device were analyzed with two samples. The paired t test showed no statistically significantly difference between the data of targets measured by both methods (t < t(0.05/2,99)=1.984, P >< 0.05). Different kinds of operation based on CAPN were performed upon 137 cases success fully. CAPN was proved reliable. All operations were successful and the clinic effects satisfactory. CONCLUSION: CAPN is accurate and reliable, and has positive effect on the improvement of stereotactic neurosurgery.

Adolescent↗

PubMed2002

[Stereotactic biopsy for intracranial deep lesions].

OBJECTIVE: To investigate the histological diagnostic efficacy and accuracy of stereotactic biopsy for intracranial deep lesions under computerized tomography (CT) and magnetic resonance imaging (MRI) guidance. METHODS: CT or MRI-guided stereotactic biopsy was performed in 605 cases with intracranial deep lesions. All the procedures were done under local anesthesia with Leksell stereotactic system. CT or MRI film was used to determine the coordinate in 450 cases and the computer-assisted planning for neurosurgery (CAPN) in 155 cases. RESULTS: Brain tumors, inflammatory lesions, and abnormal but nonspecific lesions were diagnosed pathologically in 537 cases (88.75%), 30 cases (4.96%), and 13 cases (2.15%) respectively. In 20 cases (3.31%) the biopsy procedure failed to provide useful pathological evidence. The total positive rate of biopsy was 96.69%. Complications associated with biopsy occurred in 18 patients (2.98%), and 2 patients (0.33%) died following the procedure. CONCLUSION: Stereotactic biopsy using MRI-guided stereotactic approach or CT-guided technique is a safe and reliable method for histological diagnosis of intracranial deep lesions.

Adolescent↗

PubMed2002

Maximal induction of a subset of interferon target genes requires the chromatin-remodeling activity of the BAF complex.

The mammalian SWI/SNF-like chromatin-remodeling BAF complex plays several important roles in controlling cell proliferation and differentiation. Interferons (IFNs) are key mediators of cellular antiviral and antiproliferative activities. In this report, we demonstrate that the BAF complex is required for the maximal induction of a subset of IFN target genes by alpha IFN (IFN-alpha). The BAF complex is constitutively associated with the IFITM3 promoter in vivo and facilitates the chromatin remodeling of the promoter upon IFN-alpha induction. Furthermore, we show that the ubiquitous transcription activator Sp1 interacts with the BAF complex in vivo and augments the BAF-mediated activation of the IFITM3 promoter. Sp1 binds constitutively to the IFITM3 promoter in the absence of the BAF complex, suggesting that it may recruit and/or stabilize the BAF complex binding to the IFITM3 promoter. Our results bring new mechanistic insights into the antiproliferative effects of the chromatin-remodeling BAF complex.

Animals↗

PubMed2002

[Variations of apolipoprotein A IV gene in Chinese endogenous hypertriglyceridemics].

OBJECTIVE: The aim of this study was to investigate variations of apolipoprotein A IV (apo A IV) gene and its relation to endogenous hypertriglyceridemia(HTG) in Chinese population. METHODS: One hundred and six endogenous hypertriglyceridemics and 171 healthy subjects from a population of Chinese Han nationality in Chengdu area were studied using restriction fragment length polymorphisms (RFLPs) and sequencing of apoA IV gene amplified by polymerase chain reaction (PCR). The polymorphic sites of apo A IV gene studied included codon 9 (A to G, synonymous mutation), codon 347 (A to T, non-synonymous mutation), codon 360 (G to T, non-synonymous mutation), and Msp I polymorphism (CC/TGG) within intron 2. RESULTS: The frequency of G allele at codon 9 in HTG group was higher than that in healthy controls(0.453 vs 0.366, P<0.05). The other polymorphic sites showed no significant differences of the allele frequencies between the two groups. The frequencies of rare alleles, such as G allele at codon 9, T allele at codon 347 and T allele at codon 360 polymorphic site were significantly different from those reported in European Caucasians (0.366 vs 0.032, P<0.001, 0.000 vs 0.160, P<0.001; 0.000 vs 0.070, P<0.001), but no differences were found when compared with those in Japanese, including Msp I site (P>0.05). In the healthy male control group, subjects with genotype G/G of codon 9 had a higher serum mean concentration of apoA I when compared with that of genotype A/A(P<0.01). In the HTG group, subjects with genotype C/T of Msp I site had a higher serum mean concentration of TG with compared with those with genotype C/C and T/T (P<0.05). This difference was only observed in male HTG group when male and female subgroups were further separated. CONCLUSION: These results suggest that Msp I and codon 9 polymorphism in apoA IV gene are associated with endogenous hypertriglyceridemia to some extent in Chinese population.

Adult↗

PubMed2002

Inhibitive effects of glucose and free fatty acids on proliferation of human vascular endothelial cells in vitro.

OBJECTIVES: To investigate the effects of glucose and free fatty acids (FFAs) on the proliferation and cell cycle of human vascular endothelial cells in vitro, and to examine whether the combined presence of elevated FFAs and glucose may cross-amplify their individual injurious effects. METHODS: Cultured human vascular endothelial cells (ECV304) were incubated with various concentrations of glucose and/or FFAs (palmitate and/or oleate) for 24 - 96 h. Morphologic alterations were observed using a phase contrast microscope and an electron microscope. Inhibition of proliferation was measured by a colorimetric 3-[4, 5-dimethyl thiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay. Cell viability was determined using trypan blue exclusion. Distribution of cells along phases of the cell cycle was analyzed by flow cytometry. RESULTS: Glucose 15 or 30 mmol/L, palmitate (PA) 0.25 or 0.5 mmol/L, and oleate (OA) 0.5 mmol/L inhibited proliferation and accelerated death of endothelial cells in a dose-and-time-dependent manner. After treatment with elevated glucose and/or FFAs, the G(0)/G(1) phase cells increased, whereas S phase cells decreased, suggesting that high glucose and/or FFAs mainly arrested endothelial cells at G(0)/G(1) phase. The inhibitive rates of proliferation and population of dead cells in endothelial cells incubated with glucose plus FFAs (glucose 30 mmol/L + PA 0.25 mmol/L, glucose 30 mmol/L + OA 0.5 mmol/L, glucose 30 mmol/L + PA 0.25 mmol/L + OA 0.5 mmol/L) increased more markedly than those treated with high glucose or FFAs (PA and/or OA) alone. CONCLUSION: Both high ambient glucose and FFAs can inhibit proliferation and accelerate death of endothelial cells in vitro. These changes were cross-amplified in the combined presence of high levels of glucose and FFAs.

Cell Division↗

PubMed2002

[The paraoxonase Gln-Arg 192 polymorphism in patients with endogenous hypertriglyceridemia in Chinese population].

OBJECTIVE: To investigate the 192 Gln-Arg polymorphism of paraoxonase (PON) gene and its relationship with serum lipids and apolipoproteins (apo) levels in patients with endogenous hypertriglyceridemia in Chinese population in Chengdu area. METHODS: The genotype and allele frequencies of paraoxonase gene 192 Gln-Arg polymorphism were assayed by polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP). Serum lipids were measured by enzymatic kits and apolipoproteins AI, A II, B100, C I, C II and E were measured by the RID kits developed by the Apolipoprotein Research Unit of this university in 128 HTG patients whose fasting serum TG levels were > or = 2.26 mmol/L and 129 healthy subjects whose fasting serum TG levels were < 1.82 mmol/L and TC levels < 6.2 mmol/L from a population of Chinese Han nationality in Chengdu area. RESULTS: Both in HTG group and control group, the QR genotype of PON gene was the major one, and the frequencies were 0.515 and 0.581 respectively. No differences were found in PON gene Gln-Arg polymorphism between the HTG group and the control group. In the control group, the QQ genotype of PON gene was found to have higher serum apoA I levels, compared with the RR genotype (P < 0.05). But in the HTG group, when compared with the RR genotype, the QQ genotype was found to have lower serum apoA I and A II levels and higher serum apoE levels. CONCLUSION: These may be an association of the QQ genotype of the paraoxonase 192 Gln-Arg polymorphism with the decrease of serum apoA I level and the increase of serum apoE level in endogenous hypertriglyceridemica.

Aged↗

PubMed2002

[Angiotensinogen and angiotensin-I converting enzyme gene variations in Chinese pregnancy induced hypertension].

OBJECTIVE: This study was designed to observe the genotype and allele frequency of angiotensinogen (AGT) and angiotensin-I converting enzyme (ACE) genes in pregnancy induced hypertension (PIH) and compare them with those in normal pregnant women. METHODS: Eighty-one women with pre-eclampsia (median age 28 years) and 205 normal pregnant women as controls (median age 28 years) from a population of Chinese Han nationality in Chengdu area participated in this study. The pregnant patients whose blood pressure exceeded 140/90 mmHg (or 18.7/12 kPa) were recruited with a rigorous definition of pre-eclampsia. Genotyping was performed using PCR-amplified DNA fragment for ACE I/D and PCR-RFLP for AGT polymorphism. RESULTS: The allele frequencies of AGT235T and ACE D in PIH and normal pregnant women were 0.856 vs. 0.846 and 0.333 vs 0.364, respectively. No significant difference in these allele frequencies was observed between PIH and normal pregnant women. The allele frequencies of ACE D in Caucasians were higher than those in Chinese population (P < 0.001). The allele frequencies of AGT235T in Caucasians (0.350-0.482) and other populations (0.620-0.739) were lower than that in Chinese (0.846) (P < 0.01, P < 0.001). CONCLUSION: There was no evidence in this study for the association of AGT M235T and ACE I/D polymorphism with pre-eclampsia in Chinese population in Chengdu area.

Adult↗

PubMed2002

[Analysis of serum lipid and apolipoprotein levels in pregnancy-induced hypertension and normotensive pregnant women].

OBJECTIVE: To investigate the serum lipid and apolipoprotein levels in pregnancy-induced hypertension (PIH or pre-eclampsia), normotensive pregnant women and non-pregnant women. METHODS: Twenty-eight women with PIH, 31 normatensive and 24 non-pregnant ones were studied, from whom maternal blood samples were collected. Serum lipid levels were measured by enzymatic method and apolipoproteins AI, B100, C II, CIII and E levels by radial immunodiffusion kits developed by our Lab. RESULTS: 1. Serum TG, apoC II and apoC III were highly increased in normotensive pregnant women by 3.5, 2.4 and 2.8 times respectively, when compared with those in non-pregnant ones (P < 0.001); serum TC, nHDL-C and apoAI, B100 and E were also increased in normotensive pregnant women by 21%, 33%, 55%, 79% and 77% respectively, when compared with those in non-pregnant ones (P < 0.001). TG/HDL-C in normotensive pregnant women was also significantly, higher than that in non-pregnant ones(P < 0.01). Serum HDL-C levels remained unchanged in both groups. 2. Serum TG, apoC II and apoC III were highly increased in PIH patients by 2.3, 4.0 and 2.8 times respectively, when compared with those in non-pregnant ones (P < 0.001); serum TC, nHDL-C and apoAI, B100 and E were also increased in PIH patients by 27%, 26%, 52%, 90% and 67% respectively, when compared with those in non-pregnant ones (P < 0.001) TG/HDL-C in PIH patients was also significantly higher than that in non-pregnant ones (P < 0.01). Serum HDL-C levels were increased in PIH patients by 29%, when compared with non-pregnant women. Only serum HDL-C level in PIH patients was higher than that in normotensive pregnant women. No significant differences were seen in other lipid and apolipoprotein levels between PIH patients and normotensive pregnant ones. 3. There was no significant difference in the levels of serum lipid and apolipoprotein between the subgroups of PIH patients according to the severity of the disease. CONCLUSION: The increase of serum lipid and apolipoprotein levels in PIH is probably not the predictor for pre-eclampsia.

Adult↗

PubMedDate not supplied

Hammett equation and generalized Pauling's electronegativity equation.

Substituent interaction energy (SIE) was defined as the energy change of the isodesmic reaction X-spacer-Y + H-spacer-H --> X-spacer-H + H-spacer-Y. It was found that this SIE followed a simple equation, SIE(X,Y) = -ksigma(X)sigma(Y), where k was a constant dependent on the system and sigma was a certain scale of electronic substituent constant. It was demonstrated that the equation was applicable to disubstituted bicyclo[2.2.2]octanes, benzenes, ethylenes, butadienes, and hexatrienes. It was also demonstrated that Hammett's equation was a derivative form of the above equation. Furthermore, it was found that when spacer = nil the above equation was mathematically the same as Pauling's electronegativity equation. Thus it was shown that Hammett's equation was a derivative form of the generalized Pauling's electronegativity equation and that a generalized Pauling's electronegativity equation could be utilized for diverse X-spacer-Y systems. In addition, the total electronic substituent effects were successfully separated into field/inductive and resonance effects in the equation SIE(X,Y) = -k(1)F(X)F(Y) - k(2)R(X)R(Y) - k(3)(F(X)R(Y) + R(X)F(Y)). The existence of the cross term (i.e., F(X)R(Y) and R(X)F(Y)) suggested that the field/inductive effect was not orthogonal to the resonance effect because the field/inductive effect from one substituent interacted with the resonance effect from the other. Further studies on multi-substituted systems suggested that the electronic substituent effects should be pairwise and additive. Hence, the SIE in a multi-substituted system could be described using the equation SIE(X1, X2, ..., Xn) = Sigma(n-1)(i=1)Sigma(n)(j=i+1)k(ij)sigma(X)isigma(X)j.

Journal Article↗