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Biomedical subjects

Wei Xie

Publications and source records attributed to Wei Xie.

At least 37 records · Page 2Linked to original sources

[Experimental study of glucocorticoid in the treatment of acute respiratory distress syndrome induced by E.coli].

OBJECTIVE: To evaluate the effect of glucocorticoid (GC) in the treatment of septic acute respiratory distress syndrome (ARDS). METHODS: ARDS model was reproduced by intraperitoneal injection of E.coli in piglets. Nine male piglets were randomly divided into control (C group), early (GC1) and middle (GC2) stage treatment groups. In the latter two groups methylprednisolone 20 mg was intravenously,given every 12 hours (4 mg(-1)xkg(-1)xd(-1)). All of the clinical data and survival time during 72 hours were collected and analyzed, including the collection of bronchioalveolar lavage fluid (BALF) for the determination of total protein (TP), total phospholipids (TPL), disaturated phosphatidyl choline (DSPC), and measurement of alveolar tension. Ratio of pulmonary wet and dry(W/D) weight was determined routinely, and pathological changes and their severity were evaluated by optical microscope and Smith scores. RESULTS: ARDS model was reproduced at (8.3+/-8.5) hours, and survival time of three groups was (11.0+/-6.6) hours, (35.3+/-12.5) hours and (52.5+/-13.8) hours respectively. Animals in GC1 and GC2 survived longer than those in C group, but there was no statistically significant difference among them (both P>0.05).Oxygen index (PaO(2)/FiO(2)) and mean arterial pressure (MAP) were improved in GC1 much better than those of controls (both P<0.05), and the same was true in GC2 as compared that before GC treatment (P<0.05 or P<0.01). There were no significant differences among TPL, DSPC, white blood cell count (WBC) of BALF in each group, so were lung surface tension and W/D (all P>0.05). TP of BALF was significantly higher in GC1 than that in GC2. Compared with C group, alveolar and interstitial edema, inflammation and hemorrhage were more severe in GC1 (all P<0.01), hyaline membrane was less(P<0.01) and no difference in atelectasis (P>0.05). The alveolar and interstitial edema and inflammation in GC2 were more severe than in C group(all P<0.01), and there was no difference in hemorrhage and hyaline membrane formation (both P>0.05). CONCLUSION: GC might improve hypoxemia and septic shock as a result of septic ARDS. But the treatment has no influence on pulmonary surfactant (PS), surface tension and lung pathology of ARDS in piglets challenged with intraperitoneal E.coli.

Animals↗

[Effect of different doses of atorvastatin on adhesion molecules of the patients undergoing percutaneous coronary intervention].

OBJECTIVE: To determine the effect of different doses of atorvastatin on the serum soluble intercellular adhesion molecules-1 (sICAM-1) in patients undergoing percutaneous coronary intervention (PCI). METHODS: The study consisted of 38 patients with unstable angina and 10 patients with old infarction who underwent elected PCI for stenotic lesions of the coronary artery. Patients were randomly assigned to either aggressive group or conventional one. After PCI the patients took atorvastatin 20 mg per day or 10 mg per day. Blood lipid profile was examined before, and 3 months after the PCI. SICAM-1 was examined before the PCI, 48 hours and 3 months after the PCI. RESULTS: The total cholesterol and LDL-Cholesterol 3 months after the PCI in the 2 groups were lower than those before the PCI (P<0.01). The aggressive group showed greater reduction in concentrations of TC and LDL-C than the conventional group (P<0.01). The changes in concentrations of HDL-C between pre-PCI and 3 months after the PCI and TG were not obvious (P>0.05). sICAM-1 in the 2 groups 48 hours after the PCI significantly higher than that before the PCI (P<0.01). But sICAM-1 in the 2 groups 3 months after the PCI significantly lower than that before the PCI (P<0.01 or P<0.05). The aggressive group showed greater reduction than the conventional group (P<0.01). TC and LDL-C were positively correlated with sICAM-1(r=0.2413, r=0.2691, all P<0.05). CONCLUSION: Atorvastatin 20 mg per day reduces TC, LDL-C, and sICAM-1 to a greater extent than atorvastatin 10 mg per day. The effect on sICAM-1 is partly related to reduce lipid profile.

Aged↗

Residue-rotamer-reduction algorithm for the protein side-chain conformation problem.

MOTIVATION: The protein side-chain conformation problem is a central problem in proteomics with wide applications in protein structure prediction and design. Computational complexity results show that the problem is hard to solve. Yet, instances from realistic applications are large and demand fast and reliable algorithms. RESULTS: We propose a new global optimization algorithm, which for the first time integrates residue reduction and rotamer reduction techniques previously developed for the protein side-chain conformation problem. We show that the proposed approach simplifies dramatically the topology of the underlining residue graph. Computations show that our algorithm solves problems using only 1-10% of the time required by the mixed-integer linear programming approach available in the literature. In addition, on a set of hard side-chain conformation problems, our algorithm runs 2-78 times faster than SCWRL 3.0, which is widely used for solving these problems. AVAILABILITY: The implementation is available as an online server at http://eudoxus.scs.uiuc.edu/r3.html

Algorithms↗

Polymorphisms of estrogen-metabolizing genes and breast cancer risk: a multigenic study.

BACKGROUND: Endogenous estrogen plays a very important role in the carcinogenesis and progression of breast cancer. The enzymes involved in the biosynthesis and metabolism of estrogen have been proposed to contribute to this effect. To examine this hypothesis, we conducted a case-control study to investigate the relationship between polymorphisms of genes responsible for estrogen biosynthesis (CYP17, cytochrome P450c17a and CYP19, aromatase cytochrome P450) and estrogen sulfation of inactivation (SULT1A1, sulfotransferase1A1) and the risk of breast cancer in Chinese women. METHODS: This study involved 213 breast cancer patients and 430 matched controls. PCR-based restriction fragment length polymorphism (RFLP) and short tandem repeat polymorphism (STRP) assays were used to detect the mononucleotide transition of CYP17 and SULT1A1 and tandem repeat polymorphism of CYP19. Logistic regression analyses were used to determine OR and 95% CI of each and all three high-risk genotypes, of all three genotypes combined, and of estrogen exposure factors. The relationship between each high-risk genotype and clinicalpathological characteristics were also assessed. RESULTS: The frequency of A2 allele of CYP17 was 49.8% in cases and 49.1% in controls (P = 0.82). The frequency of His allele of SULT1A1 was significantly higher in cases (13.6%) than in controls (9.5%) (P < 0.05). There was also significant difference of the (TTTA) 10 allele of CYP19 which was 12.4% in cases and 8.2% in controls (P < 0.05). When the CYP17 A2 allele, CYP19 (TTTA) 10 and SULT1A1 His allele were considered as the "putative high-risk" genotype, there was an increased risk of breast cancer with the number of high-risk genotypes in a dose-response effect (trend, P = 0.05). In multivariate analysis, the SULT1A1 genotype remained the most significant determinant for breast cancer, with OR = 2.37 (95% CI 1.23-4.74), followed by CYP19, with OR = 1.75 (95% CI 1.27-3.56). The (TTTA) 10 allele of CYP19 was associated with tumor size, and the His allele of SULT1A1 associated with status of lymph node metastasis. CONCLUSIONS: This study supports the hypothesis that breast cancer can be initiated by estrogen exposure and that estrogen metabolizing genes are involved in this mechanism. This multigenic model is useful for identifying individuals who are at higher risks of breast cancer.

Adult↗

Relationship between the downregulation of HLA class I antigen and clinicopathological significance in gastric cancer.

AIM: To discuss the expression of human leukocyte antigen (HLA) class I antigens in gastric cancer and correlate these with pathologic type and TNM stage. METHODS: The expression of HLA class I antigen was detected by immunohistochemistry in 185 specimens of gastric cancer, 20 gastric cancer specimens with lymphatic metastasis and 22 controls of normal gastric mucosa using four monoclonal antibodies. RESULTS: The expression of HLA class I antigen (B/C locus) was significantly downregulated in gastric cancer and in lymphatic metastasis than that in normal gastric mucosa (chi2=7.712, P<0.05). The expression of other HLA class I antigens was also downregulated, but the change was slight. There was no relationship between the downregulation of HLA class I antigen and that of beta2m and LMP2. The expression of HLA class I (B/C locus) was statistically correlated with pathologic stage in gastric adenocarcinoma (chi2=4.164, P<0.05). CONCLUSION: The expression of HLA class I antigen (B/C locus) was obviously downregulated in gastric cancer and in lymphatic metastasis. This abnormal expression would provide the tumor cells with a way to avoid immunological recognition.

Adult↗

The anti-endotoxic effect of o-aminobenzoic acid from Radix Isatidis.

AIM: To study the anti-endotoxic effect of o-aminobenzoic acid (OABA) isolated from Banlangen(BLG). METHODS: OABA was extracted and isolated from BLG and diluted into 0.5% solution. The concentration of endotoxin (ET) pretreated with OABA was quantitatively detected using Limulus test. The inhibition of ET-induced fever by OABA was measured in rabbits. The rates of lipopolysaccharides (LPS)-induced death in mice pretreated with or without OABA were then compared. The influence of OABA on the release of TNF-alpha and NO from macrophages induced by LPS was examined in mice. RESULTS: After pretreatment with OABA, 84.4% of ET was destroyed. The ET-induced fever in rabbits decreased significantly and the rate of LPS-induced death in mice dropped from 70% to 20%. The release of TNF-alpha and NO induced by LPS in mice was inhibited dose-dependently when the concentration of OABA was between 0.125% and 0.5%. CONCLUSION: OABA isolated from BLG has an anti-endotoxic effect.

Animals↗

[Preparation and characterization of monoclonal antibody against ARL-1 protein].

AIM: To prepare monoclonal antibodies against aldose reductase-like(ARL-1)protein. METHODS: Purified ARL-1 protein (ARL-GST) was used to immunize BALB/c mice, and mAbs were prepared by hybridoma technique. The mAbs against ARL-1 were detected by ELISA, Western blot and immunohistochemical staining respectively. RESULTS: One clone of hybridoma secreting specific mAb against ARL-1 was obtained. The Ig subclass of mAb was of IgG2b and the titre of the antibody in ascites was 1:4.096 x 10(5). Highexpression of ARL-1 protein in liver cancer was detected. CONCLUSION: The specific mAb against ARL-1 lays the foundation for investigation of functions of ARL-1 protein and relationship between ARL-1 protein and liver cancer.

Aldehyde Reductase↗

[Construction of DNMT1 siRNA stable expressing vector and evaluation of its silenced efficiency in blocking gene expression].

OBJECTIVE: To construct the specific stable expression and high efficiency small interfering RNA(siRNA) expression vector that can block DNMT1 gene function. METHODS: Using vector-based RNA interference technique, the authors constructed a vector to transcribe functional short interfering RNA (RNAi). After transfection by lipofectmine (TM) reagent, the treated cells were selected by G418. The expression levels of RNA and protein of DNMT1 were analyzed by reverse transcription polymerase chain reaction(RT-PCR) and Western blotting. The status of methylation of E-cadherin was analyzed by methylation-specific PCR(MSP). RESULTS: The expression level of endogenous DNMT1 mRNA in transfected SMMC-7721 cell lines with DNMT1 RNAi construct was 43% less than that in control cell 7721-pSU cell lines. The protein level in the former was about 10% less than that in the latter. The efficiency of the siRNA of DNMT1 was found to be higher than 90%. Demethylation of promoter of E-cadherin was obtained due to the inhibition of DNMT1. CONCLUSION: DNMT1 siRNA stable expressing vector was obtained by gene-recombined technology. There was no complete sameness between the levels of protein and RNA in gene silenced cell lines. The efficiency of the siRNA should be confirmed by Western-blotting.

Blotting, Western↗

[Preparation and characterization of monoclonal antibodies against AR protein].

AIM: To prepare monoclonal antibodies (mAbs) against aldose reductase (AR) and compare with anti-aldose reductase-like protein (ARL-1) mAb. METHODS: The AR gene was gained by RT-PCR and inserted into pGEX-4T-1 (His)(6)C. Recombinant protein GST-AR was used to immunize BALB/c mouse. MAb was prepared by hybridoma technique and detected by ELISA and Western blot. Simultaneously, according to the analysis of AR by software Clustalx and Antheprot, GST-dAR(80-142 aa), GST-dA1(1-79 aa), GST-dA2(80-99 aa), GST-dA3(111-142 aa) and GST-dA4(143-316 aa) were expressed in E. coli Rosetta. All the proteins were used to analyze the binding sites of the mAb and AR protein by Western blot. RESULTS: Three clones secreting anti-AR mAb were obtained. They were all of IgG1. And the titer of mAb in ascites was 1:400,000 while in cell culture was 1:10,000. All of the three anti-AR mAbs reacted to GST-AR and proteins of placenta tissues and had no cross-reaction to GST-ARL-1 and GST protein. And the three anti-AR mAb could recognize GST-dA1, GST-dA3 and GST-dA4, respectively. CONCLUSION: Three specific mAbs against AR are obtained and recognize the 1-79, 111-142, 143-316 amino acid sites of AR, respectively. The anti-AR mAb, together with the anti-ARL-1 mAb, may be a useful tool for further study of the function of AR and ARL-1 and the relationship between the two proteins and relevant diseases as well as for the epidemiological investigation.

Aldehyde Reductase↗

Identification of potential genes regulated by DNA methyltransferase 3B in a hepatocellular carcinoma cell line by RNA interference and microarray analysis.

Whether DNA methyltransferase 3B (DNMT3B) is deregulated in hepatocellular carcinoma cell lines is still unclear. The expression levels of DNMT3B protein in normal liver cell line, pericacinoma cell line and hepatocellular carcinoma cell lines were compared by both Western blotting and immunocytochemistry. Long-term downregulated DNMT3B in a hepatocellular carcinoma cell line SMMC-7721 was achieved using a RNAi recombinant plasmid. The suppression of DNMT3B induced by RNA interference was confirmed using semi-quantitative RT-PCR and Western blotting. High throughput cDNA microarray was used to analyze the expression profiling of downstream genes of DNMT3B displayed in the treated cell lines and control. In the result,DNMT3B in hepatocellular carcinoma cell lines was expressed at a significantly higher level compared to those in pericacinoma cell line and normal liver cell line. A specific DNMT3B siRNA stably expressed from a plasmid vector effectively suppressed the expression of DNMT3B in SMMC-7721 cell line. By microarray analysis,26 downregulated genes and 115 upregulated genes have been identified in the DNMT3B knockdown cell line,including some important developmental genes and tumor-related genes such as SNCG, NOTCH1, MBD3, WNT11, MAOA and FACL4. The discovery showed DNMT3B was over-expressed in most hepatocellular carcinoma cell lines examined and may be linked to the carcinogenesis of hepatocytes. An array of candidate genes that are involved in the action of DNMT3B have been identified,including those related to development.

Carcinoma, Hepatocellular↗

Gene expression profiling in the inductive human hematopoietic microenvironment.

Human hematopoietic stem cells (HSCs) and their progenitors can be maintained in vitro in long-term bone marrow cultures (LTBMCs) in which constituent HSCs can persist within the adherent layers for up to 2 months. Media replenishment of LTBMCs has been shown to induce transition of HSCs from a quiescent state to an active cycling state. We hypothesize that the media replenishment of the LTBMCs leads to the activation of important regulatory genes uniquely involved in HSC proliferation and differentiation. To profile the gene expression changes associated with HSC activation, we performed suppression subtractive hybridization (SSH) on day 14 human LTBMCs following 1-h media replenishment and on unmanipulated controls. The generated SSH library contained 191 differentially up-regulated expressed sequence tags (ESTs), the majority corresponding to known genes related to various intracellular processes, including signal transduction pathways, protein synthesis, and cell cycle regulation. Nineteen ESTs represented previously undescribed sequences encoding proteins of unknown function. Differential up-regulation of representative genes, including IL-8, IL-1, putative cytokine 21/HC21, MAD3, and a novel EST was confirmed by semi-quantitative RT-PCR. Levels of fibronectin, G-CSF, and stem cell factor also increased in the conditioned media of LTBMCs as assessed by ELISA, indicating increased synthesis and secretion of these factors. Analysis of our library provides insights into some of the immediate early gene changes underlying the mechanisms by which the stromal elements within the LTBMCs contribute to the induction of HSC activation and provides the opportunity to identify as yet unrecognized factors regulating HSC activation in the LTBMC milieu.

Bone Marrow Cells↗

Nek2A specifies the centrosomal localization of Erk2.

Nek2A is a cell-cycle-regulated protein kinase that localizes to the centrosome and kinetochore. Our recent studies provide a link between Nek2A and spindle checkpoint signaling [J. Biol. Chem. 279 (2004) 20049]. Extracellular signal-regulated kinase 2 (Erk2) is an important kinase, which belongs to mitogen activating protein (MAP) kinase family. Here we demonstrated that Nek2A binds specifically to Erk2. Erk2 interacts with Nek2A via a conserved Erk2 docking site located to the C-terminus of Nek2A. Our studies indicate this docking site is essential and sufficient for a direct Nek2A-Erk2 interaction. In addition, our immunocytochemical studies show that Nek2A and Erk2 are co-localized to centrosome. Significantly, elimination of Nek2A by RNA interference delocalized Erk2 from its centrosomal location, while inhibition of Erk2 kinase activity did not affect the localization of Nek2A in centrosome. We propose that Erk2 links extracellular signaling to centrosome dynamics by Nek2A.

Amino Acid Sequence↗

Sulfotransferase 1A1 (SULT1A1) polymorphism and breast cancer risk in Chinese women.

BACKGROUND: Sulfonation catalyzed by sulfotransferase enzymes plays an important role in chemical defense mechanisms against various xenobiotics but also bioactivates carcinogens. A major human sulfotransferase, SULT1A1, catalyzes the sulfation of a variety of phenolic and estrogenic compounds. A functional polymorphism of the SULT1A1 gene has been implicated in a decreased activity and thermostability when the wild-type arginine (Arg) at codon 213 is substituted by a histidine (His). METHODS: We investigated the association between the His allele and the risk breast cancer in 213 cases and 430 matched controls in Chinese women, and the interaction between His allele and endogenous estrogen and dietary mutagens exposure factors were also determined by use of logistic regression analysis. RESULTS: There was no significant difference in genotypes between the cancer patients and control populations. However, the frequency of the His allele in cases (13.6%) were significant higher than that in controls (9.5%), P = 0.03. Compared with women carrying the Arg/Arg genotype, the adjusted odds ratio (OR) of Arg/His was 1.48 (95% CI = 0.59-3.31) and His/His was 2.28 (95% CI = 0.69-9.58), P trend was 0.04. The adjusted OR of Arg/His + His/His was 2.60 (95% CI = 1.12-6.05). His allele strengthen the effect of endogenous estrogen exposure with interaction index r > 1, and weaken the effect of heterocyclic amines and polycyclic aromatic hydrocarbons derived from dietary with interaction index r > 1, both were multiplicative interaction model. CONCLUSIONS: Our findings suggest that the SULT1A1 His allele was positively associated with the risk of breast cancer in Chinese women. And there was interaction between SULT1A1 polymorphism and related exposure factors.

Adult↗

Evaluation of the ability of digital infrared imaging to detect vascular changes in experimental animal tumours.

Infrared imaging has frequently been used in the past to detect changes in skin surface temperature associated with breast cancer. Usually a 1-2 degrees C elevation in skin surface temperature is observed at the tumour periphery, and it has been proposed that this change is due to hypervascularity resulting from tumour-associated angiogenesis. In our study, we used the rat mammary adenocarcinoma 13762 MAT, a tumour that has been used to identify antiangiogenic drugs, to investigate whether infrared imaging can detect angiogenesis in malignant tumours. If successful, it was hoped that this technique would represent a simple, noninvasive, procedure for monitoring the activity of antiangiogenic drugs. It was found that, unlike breast cancer patients, no tumour-associated increase in skin surface temperature was observed, but a constant and highly significant reduction in temperature was noted that was independent of tumour size and was produced by relatively small tumours (>/= 0.5 cm in diameter). The explanation for this effect is unclear but it may be due to the poorly vascularised nature of rapidly growing tumours. Nevertheless, our study indicates that the peripheral temperature elevation reported in breast cancer patients is unlikely to be due to hypervascularity resulting from tumour-induced angiogenesis. An alternative explanation is that the temperature increase is due to a chronic inflammatory response around developing breast tumours. With increasing evidence that inflammation can enhance tumour growth and is associated with a poor prognosis, this suggestion implies that infrared imaging may have considerable prognostic value.

Adenocarcinoma↗

[Expression analysis of mouse homologous proteins with human aldose reductase like-1].

OBJECTIVE: To detect expression of mouse ARL-1 homologous proteins in mouse tissues, and analyze homology, genetic distance and phylogenetic relationship between human aldose reductase like-1 (ARL-1) and mouse homologous proteins. METHODS: Homology of mouse ARL-1 homologous proteins with human ARL-1 was analyzed by software Clustal X 1.8 using GenBank and Swiss-Prot database; genetic distance and phylogenetic relationship between mouse ARL-1 homologous proteins and human ARL-1 were analyzed by software Mega 2.0; mouse tissues were detected by Western blotting using polyclonal antibodies against ARL-1 protein from domestic rabbits. RESULTS: The amino acid sequence of human ARL-1 was 83%, 82%, 81%, 79%, 70%, 51%, 50% and 45% identical to that of the Chinese hamster ovary reductase (CHO-Red), the mouse fibroblast growth factor-regulated protein (FR-1), rat aldose reductase-like protein (rARLP), the mouse vas deferens protein (MVDP), rat lens aldose reductase (LeAR), delta4-3-ketosteroid-5beta-reductase (5beta-Red), rat aldo-keto reductase protein c (RaK-c) and 3alpha-hydroxysteroid dehydrogenase (3alpha-HSD). Among all the mouse ARL-1 homologous proteins, the genetic distance between CHO-Red and human ARL was the shortest (18.0%, P = 0.023), next was FR-1 (19.1%, P=0.023) and rARLP (19.9%, P = 0.025). From the phylogenetic tree, the protein whose relationship with human ARL-1 was the closest with CHO-Red, next was mouse FR-1, rARLP, MVDP and LeAR. Homologous proteins were found in mouse tissues including vas deferens, testis, bladder and uterus by Western blotting using polyclonal antibodies against ARL-1 protein from domestic rabbits. CONCLUSIONS: CHO-Red has the highest homology, the shortest genetic distance and the closest relationship with human ARL-1, next is FR-1, rARLP, MVDP. The major distribution of mouse ARL-1 homologous proteins is in vas deferens, testis, bladder and uterus, deducing they might be CHO-Red, FR-1, rARLP or MVDP

ADP-Ribosylation Factors↗

[Role of PD153035 in the induction of apoptosis of XG-1 myeloma cell line].

OBJECTIVE: To study the role of epidermal growth factor receptor (EGFR) in the proliferation and survival of human myeloma cells. METHODS: The inhibitor of EGFR, PD153035, was used to block the signal transduction of EGFR. The proliferation and apoptosis of myeloma cell line, XG-1, were detected by 3H-TCR incorporation assay and Annexin V staining analysis, respectively. The phosphatation of STAT3, the key activate signal to the myeloma cell proliferation, was detected with Western blot. RESULTS: PD153035 decreased the proliferation of XG-1 and induced an obvious apoptosis in XG-1. The phosphatation of STAT3 induced by HB-EGF but not by IL-6 was blocked by PD153035. CONCLUSION: The proliferation and survival of myeloma cells may be suppressed by PD153035 due to the blockage of phosphatation of STAT3 induced by the activation of EGFR.

Antineoplastic Agents↗

[Effect of saikosaponins on epileptic rat electroenciphalogram].

OBJECTIVE: To study the effect of saikosaponins on the electroencephalogram (EEG) of epileptic rats to evaluate its therapeutic effect against epilepsies. METHODS: Sixty 8-week-old healthy SD rats were randomized into normal control group (A), epileptic model group (B), lamotrigine group (C), and 3 saikosaponin groups of small, moderate and high doses (D, E, and F groups, respectively), with 10 rats in each group. Penicillin was used to induce epilepsy in the latter 5 groups, and the EEG and onset of epileptic seizures were observed in each group. RESULTS: In group B, the EEG contained obvious epileptic discharges, which were not found in that in group A. After treatment with saikosaponins and lamotrignie, the EEG of group C and F became normal, whereas the EEG in group D still contained epileptic discharges at a low level, and that in group E was basically normal. The EEGs of group C, D, E, and F were significantly different from that in group B (P<0.001). CONCLUSION: Saikosaponins can obviously alleviate the severity of epileptic seizure in epileptic rats.

Animals↗