Biomedical subjects

Wen-Wei Yan

Publications and source records attributed to Wen-Wei Yan.

9 recordsLinked to original sources

PubMed2006

[Autologous versus allogeneic stem cell transplantation in adult patients with acute lymphoblastic leukemia].

OBJECTIVE: To explore the efficacy of autologous or allogeneic stem cell transplantation in adult patients with acute lymphoblastic leukemia (ALL) and investigate its relevant prognostic factors. METHODS: A total of 96 adult patients with ALL who had admitted to our hospital from November 1986 to June 2004 were followed up till February 28, 2005. They were divided into autologous stem cell transplantation (Auto-SCT) group (n = 56) and allogeneic stem cell transplantation (Allo-SCT) group (n = 40). Auto-SCT group was further divided to treated subgroup, in which patients received graft-purified transplantation and (or) maintenance immunotherapy or chemotherapy after transplantation (n = 26), and non-treated subgroup (n = 30). Clinical characteristics of these groups were retrospectively analyzed. Survival date were analyzed by the Kaplan-Meier method and the prognostic factors were analyzed with the COX regression model. RESULTS: The 1-, 3-, and 5-year leukemia-free-survival (LFS) were not significantly different between the auto-SCT group and the allo-SCT group. The 3-and 5-year LFS of auto-SCT treated subgroup, auto-SCT non-treated subgroup and allo-SCT group were [(73.0 +/- 8.7)%, (69.2 +/- 9.0)%], [(42.2 +/- 10.1)%, (35.1 +/- 10.0)%], and [(50.9 +/- 8.2)%, (50.9 +/- 8.2)%], respectively, which showed statistical significance (P < 0.05). CONCLUSIONS: The long-term LFS is similar after auto-SCT and after allo-SCT. Purified graft and maintain immunotherapy or chemotherapy post-transplantation may decrease the relapse rate after auto-SCT and improve survival.

Adolescent↗

PubMed2005

Chronic hepatitis C virus infection and post-liver transplantation diabetes mellitus.

Patients with chronic hepatitis C virus (HCV) infection have a significantly increased prevalence of type 2 diabetes mellitus compared to controls or HBV-infected patients. Moreover, the incidence rate of post-liver transplantation diabetes mellitus (PTDM) also appears to be higher among patients with HCV infection. PTDM is often associated with direct viral infection, autoimmune disorders, and immunosuppressive regimen. Activation of tumor necrosis factor-alpha may be the link between HCV infection and diabetes. In this article, we reviewed the epidemiologic association between HCV infection and PTDM, highlighting the most recent pathophysiologic insights into the mechanisms underlying this association.

Animals↗

PubMed2005

Hepatocytes targeting of cationic liposomes modified with soybean sterylglucoside and polyethylene glycol.

AIM: In this study, a hepatocyte-specific targeting technology was developed by modifying cationic liposomes with soybean sterylglucoside (SG) and polyethylene glycol (PEG) (C/SG/PEG-liposomes). METHODS: The liposomal transfection efficiencies in HepG(2) 2.2.15 cells were estimated with the use of fluorescein sodium (FS) as a model drug, by flow cytometry. The antisense activity of C/SG/PEG-liposomes entrapped antisense oligonucleotides (ODN) was determined as HBsAg and HBeAg in HepG(2) 2.2.15 cells by ELISA. The liposome uptake by liver and liver cells in mice was carried out after intravenous injection of (3)H-labeled liposomes. RESULTS: C/SG-liposomes entrapped FS were effectively transfected into HepG(2) 2.2.15 cells in vitro. C/SG/PEG-liposomes entrapped ODN, reduced the secretion of both HBsAg and HBeAg in HepG(2) 2.2.15 cells when compared to free ODN. After in vivo injection of (3)H-labeled C/SG/PEG-liposomes, higher radiation accumulation was observed in the hepatocytes than non-parenchymal cells of the liver. CONCLUSION: C/SG/PEG-liposomes mediated gene transfer to the liver is an effective gene-delivery method for hepatocytes-specific targeting, which appears to have a potential for gene therapy of HBV infections.

Animals↗

PubMed2005

Differences in platelet endothelial cell adhesion molecule-1 expression between peripheral circulation and pancreatic microcirculation in cerulein-induced acute edematous pancreatitis.

AIM: To investigate the changes of platelet endothelial cell adhesion molecule-1 (PECAM-1) expression on polymorphonuclear leukocytes (PMNs) in peripheral circulation and pancreatic microcirculation in cerulein-induced acute edematous pancreatitis (AEP). METHODS: Fifty Wistar rats were randomly divided into control group (n = 10) and AEP group (n = 40). A model of AEP was established by subcutaneous injection of cerulein 5.5 and 7.5 mug/kg at 0 and 1 h after the beginning of experiment respectively. PECAM-1 expression on PMNs from splenic vein and inferior vena cava was determined by RT-PCR at mRNA level and determined by flow cytometry at protein level. RESULTS: In experimental rats, an increased PECAM-1 mRNA expression was seen from 4 to 8 h of AEP in peripheral circulation (0.77+/-0.25%, 0.76+/-0.28%, 0.89+/-0.30%, 1.00+/-0.21%), while in pancreatic microcirculation, expression decreased from 2 h and reached the lowest level at 6 h of AEP (0.78+/-0.29%, 0.75+/-0.26%, 0.62+/-0.28%, 0.66+/-0.20%). There were significant differences at 8-h time point of AEP between peripheral circulation and pancreatic microcirculation (1.00+/-0.21% vs 0.66+/-0.20%, P<0.05). Meanwhile, the difference at protein level was also found. CONCLUSION: A reverse expression of PECAM-1 on PMNs was found between peripheral circulation and pancreatic microcirculation, suggesting that inhibition of PECAM-1 expression may improve the pathological change of AEP.

Acute Disease↗

PubMed2005

Pituitary adenylate cyclase activating-peptide and its receptor antagonists in development of acute pancreatitis in rats.

AIM: Pituitary adenylate cyclase activating-peptide (PACAP) is a late member of the secretin/glucagon/vasoactive intestinal peptide (VIP) family of brain-gut peptides. It is unknown whether PACAP takes part in the development of acute pancreatitis and whether PACAP or its antagonists can be used to suppress the progression of acute pancreatitis. We investigated the actions of PACAP and its receptor antagonists in acute pancreatitis on rats. METHODS: Acute pancreatitis was induced in rats with caerulein or 3.5% sodium taurocholate. The rats were continuously infused with 5-30 microg/kg PACAP via jugular vein within the first 90 min, while 10-100 microg/kg PACAP6-27 and (4-Cl-D-Phe6, Leu17) VIP (PACAP receptor antagonists) were intravenously infused for 1 h. Biochemical and histopathological assessments were made at 4 h after infusion. Pancreatic and duodenal PACAP concentrations were determined by enzyme-linked immunosorbent assay (ELISA). Chinese ink-perfused pancreas was fixed, sectioned and cleared for counting the functional capillary density. RESULTS: PACAP augmented caerulein-induced pancreatitis and failed to ameliorate sodium taurocholate-induced pancreatitis. ELISA revealed that relative concentrations of PACAP in pancreas and duodenum were significantly increased in both sodium taurocholate- and caerulein-induced pancreatitis compared with those in normal controls. Unexpectedly, PACAP6-27 and (4-Cl-D-Phe6, Leu17) VIP could induce mild acute pancreatitis and aggravate caerulein-induced pancreatitis with characteristic manifestations of acute hemorrhagic/necrotizing pancreatitis. Functional capillary density of pancreas was interpreted in the context of pancreatic edema, and calibrated functional capillary density (calibrated FCD), which combined measurement of functional capillary density with dry weight/wet weight ratio, was introduced. Hyperemia or congestion, rather than ischemia, characterized pancreatic microcirculatory changes in acute pancreatitis. CONCLUSION: PACAP may take part in the pathogenesis of acute pancreatitis in rats. The two PACAP receptor antagonsits might act as partial agonists. Calibrated functional capillary density can reflect pancreatic microcirculatory changes in acute pancreatitis.

Acute Disease↗

PubMed2004

Role of COX-2 in microcirculatory disturbance in experimental pancreatitis.

AIM: To elucidate the role of COX-2 in the development of capillary leakage in rats with acute interstitial pancreatitis. METHODS: Rats with acute interstitial pancreatitis were induced by caerulein subcutaneous injection. Reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the gene expression of COX-2 in pancreatic tissues, spectrophotometry was used to assay the parameters of acute pancreatitis such as the serum amylase and plasma myeloperoxidase, and determination of capillary permeability in the pancreas by quantifying the permeability index (PI) assisted response of pancreatic microvascular via intravital fluorescence microscope video image analysis system. RESULTS: A significant increase of COX-2 expression, elevation of serum amylase, and plasma myeloperoxidase were detected in rats with acute edematous pancreatitis compared with control rats. The changes of pancreatic microvascular after caerulein injection were as following: (a) the decrease of pancreatic capillary blood flow (4th h, 0.56+/-0.09 nL/min, P<0.05; 8 th h, 0.34+/-0.10 nL/min, P<0.001); (b) reduction of functional capillary density (4 th h, 381+/-9 cm(-1), P>0.05; 8th h, 277+/-13 cm(-1), P<0.001); (c) irregular and intermittent capillary perfusion was observed at the 8th h and these vessels were also prone to permeation. CONCLUSION: COX-2 plays an important role in mediating capillary permeability in pancreatitis, thereby contributing to capillary leakage.

Animals↗

PubMed2004

Effect of inducible cyclooxygenase expression on local microvessel blood flow in acute interstitial pancreatitis.

OBJECTIVE: To investigate the role of inducible cyclooxygenase (COX-2) mRNA expression in local microvessels in rats with acute interstitial pancreatitis (AIP) induced by caerulein injection. METHODS: The reverse transcription polymerase chain reaction (RT-PCR) was used to detect COX-2 gene expression in pancreatic tissue. Parameters of acute pancreatitis, such as serum amylase (AMS) and plasma myeloperoxidase (MPO) activities, were assayed using spectrophotometry. Intravital fluorescence microscopy with fluorescein isothiocyanate-labelled erythrocytes was used to study the pancreatic microvessels of rats with AIP and normal control rats. RESULTS: Highly significant increases in COX-2 expression and AMS and MPO activity were seen in rats with AIP compared with controls. After caerulein injection, pancreatic capillary blood flow was decreased (4 hours, p > 0.05; 8 hours, p < 0.001), functional capillary density was reduced (4 hours, p > 0.05; 8 hours, p < 0.001), and there was irregular and intermittent capillary perfusion at 8 hours. There was also a positive correlation between the level of COX-2 expression and MPO activity (plasma, r = 0.5449, p < 0.05; tissue, r = 0.5698, p < 0.05). CONCLUSIONS: The correlations between increased COX-2 expression and decreased capillary perfusion and blood flow and increased oedema following AIP may show that COX-2 expression can induce neutrophil sequestration to the pancreas, which may be one of the cascading inflammatory factors in the development of AIP.

Acute Disease↗

PubMed2004

[Biodistribution and hepatocytes targeting of cationic liposomes surface-modified with sterylglucoside and golyethylene glycol].

AIM: To investigate the biodistribution and the hepatocytes targeting of cationic liposome containing 3beta[N-( N',N'-dimethylaminoethane) carbamoyl] cholesterol (DC-Chol) and surface-modified liposomes with sterylglucoside (SG) and polyethylene glycol-distearoylphosphatidylethanolamine (PEG-DSPE). METHODS: Cationic liposomes (CL) composed of DC-Chol and dipalmitoylphosphatidylcholine (DPPC), SG/PEG modified cationic liposome (SG/PEG-CL), both contained trace 3H-cholesterol (3H-Chol) as radiolabel, were prepared. The liposomes encapsulating 125I-labled antisense oligodeoxynucleotide (125I-asODN) (SG/PEG-CL-asODN) were also prepared. The biodistribution of CL, SG/PEG-CL, SG/PEG-C2-asODN as well as 125I-asODN solution, were studied. The radioactivities in hepatocytes and non-hepatocytes after administration of CL and SG/PEG-CL were determined by infuseing method. RESULTS: CL and SG/PEG CL significantly aggregated in liver. The distribution of SG/PEG CL was significantly higher in hepatocytes (P < 0.01) and lower in non-hepatocytes (P < 0.01) than that of CL. The concentrations of SG/PEG-CL-asODN in liver and spleen were significantly higher than that of asODN solution (P < 0.01). CONCLUSION: Cationic liposome modified with SG/PEG changed the distribution of asODN. Cationic liposome can target hepatocytes more effective after being modified with SG.

1,2-Dipalmitoylphosphatidylcholine↗

PubMedDate not supplied

Characteristics and biodistribution of soybean sterylglucoside and polyethylene glycol-modified cationic liposomes and their complexes with antisense oligodeoxynucleotide.

A novel cationic liposome modified with soybean sterylglucoside (SG) and polyethylene glycol-distearoylphosphatidylethanolamine (PEG-DSPE) as a carrier of antisense oligodeoxynucleotide (ODN) for hepatitis B virus (HBV) therapy was constructed. Characteristics of the cationic liposomes modified with SG and PEG (SG/PEG-CL) and their complexes with 15-mer phosphorothioate ODN (SG/PEG-CL-ODN complex) were investigated by incorporation efficiency, morphology, electrophoresis, zeta potentials, and size analysis. Antisense activity of the liposomes and ODN complexes was determined as hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) in HepG2 2.2.15 cells by ELISA. Their tissue and intrahepatic distribution were evaluated following intravenous injection in mice. The complexes gained high incorporation efficiency and intact vesicular structure with mean size at approximately 200 nm. The SG/PEG-CL-ODN complexes enhanced the inhibition of both HBsAg and HBeAg expression in the cultured HepG2 2.2.15 cells relative to free ODN. The uptake of SG/PEG-CL and nonmodified cationic liposomes (CL) was primarily by liver, spleen, and lung. Furthermore, the concentration of SG/PEG-CL was significant higher than that of CL in hepatocytes at 0.5 hr postinjection. The biodistribution of SG/DSPE-CL-ODN complex compare with free ODN showed that liposomes enhanced the accumulation of ODN in the liver and spleen, while decreasing its blood concentration. SG/PEG-CL-mediated ODN transfer to the liver is an effective gene delivery method for cell-specific targeting, which has a potential for gene therapy of HBV infections. SG and PEG-modified cationic liposomes have proven to be an alternative carrier for hepatocyte-selective drug targeting.

Animals↗