Proteinase-activated receptor 1 contributed to up-regulation of enkephalin in keratinocytes of patients with obstructive jaundice.

BACKGROUND: Skin synthesis of endogenous opioids such as enkephalin is considered to be increased in cholestatic rodents, which may induce antinociception in cholestatic liver disease. No studies have reported yet the expression of skin enkephalin in patients with cholestasis. METHODS: Electrical pain threshold, postoperative morphine consumption, and skin enkephalin expression were measured in patients with jaundice (n = 18) and control patients (n = 16). Male Sprague-Dawley rats (n = 52) and human keratinocyte cell line HaCaT were used in vivo and in vitro studies, respectively. Nociceptive thresholds and plasma and skin levels of methionine-enkephalin were compared in protease-activated receptors-1-antagonized and control bile duct-ligated rats. In in vitro study, the effect on thrombin-induced enkephalin expression was examined and the role of extracellular regulated protein kinases 1/2 and p38 was investigated. RESULTS: The authors found that: (1) the electrical pain threshold (mean ± SD) was 1.1 ± 0.1 mA in control patients, whereas it was significantly increased in patients with jaundice (1.7 ± 0.3 mA); 48-h postoperative morphine consumption was approximately 50% higher in the control group than that in the group with jaundice; (2) Skin keratinocytes enkephalin expression was increased in the patients with jaundice; (3) Protease-activated receptors-1 antagonist 1 µg·kg(-1)·day(-1) treatment to the bile duct-ligated rats significantly reduced plasma levels of methionine-enkephalin, nociceptive thresholds, and keratinocytes enkephalin expression; and (4) protease-activated receptors-1 activation induced enkephalin expression through phosphorylation of extracellular regulated protein kinases 1/2 and p38 in keratinocytes. CONCLUSION: Protease-activated receptors-1 activation in peripheral keratinocytes may play an important role in the local synthesis of enkephalin during cholestasis.

Structure determination of two new indole-diterpenoids from Penicillium sp. CM-7 by NMR spectroscopy.

Two new indole-diterpenoids 4b-deoxy-1'-O-acetylpaxilline (1) and 4b-deoxypenijanthine A (2) were isolated from the fermentation broth and the mycelia of the soil fungus Penicillium sp. CM-7, along with three known structurally related compounds, 1'-O-acetylpaxilline (3), paspaline (4) and 3-deoxo-4b-deoxypaxilline (5). The structures of compounds 1 and 2 were elucidated by extensive spectroscopic methods, especially 2D NMR, and their absolute configurations were suggested on the basis of the circular dichroism spectral analysis and the NOESY data.

MicroRNA-98 and microRNA-214 post-transcriptionally regulate enhancer of zeste homolog 2 and inhibit migration and invasion in human esophageal squamous cell carcinoma.

BACKGROUND: The enhancer of zeste homolog 2 (EZH2) was found to be overexpressed and associated with tumor metastasis in esophageal squamous cell carcinoma (ESCC). On the other hand, it was reported that miR-26a, miR-98, miR-101, miR-124, miR-138 and miR-214 could inhibit the expression of EZH2 in some tumors. However, the role of miRNAs in the regulation of EZH2 expression in human ESCC has not been documented. The aim of this study was to determine the role of these miRNAs in the regulation of tumor metastasis via EZH2 overexpression in human ESCC. METHODS AND RESULTS: The expression of these miRNAs and EZH2 mRNA were examined by qPCR and the expression of EZH2 protein was detected by western blot. The role of these miRNAs in migration and invasion was studied in ESCC cell line (Eca109) transfected with miRNA mimics or cotransfected with miRNA mimics and pcDNA-EZH2 plasmid (without the 3'-UTR of EZH2). Through clinical investigation, we found that miR-98 and miR-214 expression was significantly lower in ESCC tissues than in matched normal tissues, and the expression level of miR-98 and miR-214 was inversely correlated to EZH2 protein expression and the clinical features such as pathological grade, tumor stage and lymph node metastasis in ESCC. In Eca109 cells, overexpression of miR-98 and miR-214 significantly inhibited the migration and invasion of ESCC cells, which was reversed by transfection of EZH2. CONCLUSIONS: These findings suggest that decreased expression of miR-98 and miR-214 might promote metastasis of human ESCC by inducing accumulation of EZH2 protein.

PRAF3 induces apoptosis and inhibits migration and invasion in human esophageal squamous cell carcinoma.

BACKGROUND: Prenylated Rab acceptor 1 domain family member 3 (PRAF3) is involved in the regulation of many cellular processes including apoptosis, migration and invasion. This study was conducted to investigate the effect of PRAF3 on apoptosis, migration and invasion in human esophageal squamous cell carcinoma (ESCC). METHODS: The expression of PRAF3 mRNA and protein in primary ESCC and the matched normal tissues (57cases) was determined by quantitative RT-PCR and Western blot. Immunohistochemical analysis of PRAF3 expression was carried out in paraffin-embedded sections of ESCC and correlated with clinical features. The role of PRAF3 in apoptosis, migration and invasion was studied in ESCC cell lines of Eca109 and TE-1 through the adenovirus mediated PRAF3 gene transfer. The effect of PRAF3 on apoptosis was analyzed by annexin V-FITC assay. The regulation of PRAF3 on migration was determined by transwell and wounding healing assay, while the cellular invasion was analyzed by matrigel-coated transwell assay. RESULTS: We found that the expression of PRAF3 was significantly down-regulated in ESCC tissue compared with the matched normal tissue and was correlated with the clinical features of pathological grade, tumor stage and lymph node metastasis. Moreover, overexpression of PRAF3 induced cell apoptosis through both caspase-8 and caspase-9 dependent pathways, and inhibited cell migration and invasion by suppressing the activity of both MMP-2 and MMP-9 in human ESCC cell lines. CONCLUSIONS: Our data suggest that PRAF3 plays an important role in the regulation of tumor progression and metastasis and serves as a tumor suppressor in human ESCC. We propose that PRAF3 might be used as a potential therapeutic agent for human ESCC.

MicroRNA-203 inhibits cell proliferation by repressing ΔNp63 expression in human esophageal squamous cell carcinoma.

BACKGROUND: This study was performed to investigate the effect of microRNA-203 (miR-203) and ΔNp63 on cell proliferation and the functional connection between miR-203 and ΔNp63 in ESCC. METHODS: We employed 2 human ESCC cell lines, Eca109 and TE-1, as the model system. The effect of miR-203 and ΔNp63 on cell proliferation was determined in cells transfected with miR-203 mimic and ΔNp63 small interfering RNA (siRNA), respectively. The regulation of ΔNp63 expression in ESCC cells by miR-203 was studied by luciferase reporter assay, RT-PCR and western blot analysis in cells transfected with miR-203. The effect of ΔNp63 re-expression on miR-203 induced inhibition of cell proliferation was studied by cell proliferation assay in cells cotransfected with miR-203 and pcDNA-ΔNp63 plasmid (without the 3'-UTR of ΔNp63). RESULTS: We found that both miR-203 and ΔNp63 siRNA signicantly inhibited cell proliferation in ESCC. MiR-203 could down-regulate endogenous ΔNp63 expression at the posttranscriptional level. Moreover, re-expression of ΔNp63 in cells transfected with miR-203 significantly attenuated the miR-203 induced inhibition of cell proliferation. CONCLUSIONS: Our data implied that miR-203 could inhibit cell proliferation in human ESCC through ΔNp63-mediated signal pathway. Therefore, we propose that miR-203 might be used as a therapeutic agent for human ESCC.

Emulsified isoflurane preconditioning reduces lung injury induced by hepatic ischemia/reperfusion in rats.

OBJECTIVE: To investigate whether emulsified isoflurane preconditioning could reduce lung injury induced by hepatic I/R in rats and its mechanism. MATERIALS AND METHODS: 32 pentobarbital-anesthetized Sprague-Dawley rats were equally randomized into four groups: laparotomy group (Sham group), hepatic I/R and normal saline infusion group (I/R+S group), I/R and lipid vehicle infusion (I/R+V group), or I/R and 8% emulsified isoflurane infusion (I/R+E group) at the rate of 8 ml·kg(-1)·h(-1) for 30 min. Blood supply of the hepatic artery and portal vein to the left and the median liver lobes was occluded for 90 min after 30-min washout time. Reperfusion was allowed to proceed for 4 h before sacrifice of the animals. Lung injury was observed histologically. Neutrophil infiltration and TNF-α concentration in serum and lung were measured. Changes of wet-to-dry weight ratios in lung tissue, ICAM-1 expression and NF-κB activity in lung after hepatic I/R were determined. RESULTS: Compared with I/R+S or I/R+V group, emulsified isoflurane preconditioning reduced hepatic I/R-induced lung histologic injury and inhibited the increase of myeloperoxidase (MPO) activity in the lung tissue markedly (5.5±1.37 and 5.22±1.33 vs 3.81±1.62 U/g, P<0.05). In addition, both serum and lung tissue TNF-α levels were reduced in I/R+E group (104.58±31.40 and 94.60±22.23 vs 72.44±17.28 pg/ml, P<0.05; 393.51±88.22 and 405.46±102.87 vs 292.62±74.56 pg/ml, P<0.01). Emulsified isoflurane preconditioning also inhibited the increase of ICAM-1 expression (0.79±0.17 and 0.84±0.24 vs 0.62±0.21, P<0.05) and NF-κB translocation (4.93±0.48 and 4.76±0.57 vs 4.01±0.86, P<0.05) in the lung tissue markedly. CONCLUSIONS: Emulsified isoflurane preconditioning markedly attenuated hepatic I/R-induced lung injury in rats, which may be hopefully applied to the clinical treatment of organ injury caused by hepatic surgery, transplantation or hemorrhagic shock.

Intrathecal siRNA against Toll-like receptor 4 reduces nociception in a rat model of neuropathic pain.

BACKGROUND: Neuropathic pain is characterized by hyperalgesia, allodynia and spontaneous pain. It often occurs as a result of injury to peripheral nerves, dorsal root ganglions (DRG), spinal cord, or brain. Recent studies have suggested that Toll-like receptor 4 (TLR4) might play a role in neuropathic pain. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we investigated the role of TLR4 in a rat chronic constriction injury (CCI) model and explored the feasibility of treating neuropathic pain by inhibiting TLR4. Our results demonstrated that intrathecal siRNA-mediated suppression of TLR4 attenuated CCI-induced mechanical allodynia and thermal hyperalgesia through inhibiting the activation of NF-kappaB p65 and production of proinflammatory cytokines (e.g., TNF-alpha and IL-1 beta). CONCLUSIONS/SIGNIFICANCE: These findings suggest that suppression of TLR4 mediated by intrathecally administered siRNA may be a new strategy for the treatment of neuropathic pain.

Association of TNFAIP3 polymorphism with rheumatic heart disease in Chinese Han population.

In a pair-matched case-control study (239 versus 478) conducted in Chinese Han population, we investigated the association between tumor necrosis factor-alpha-induced protein 3 (TNFAIP3) gene, tumor necrosis factor receptor-associated factor 1 (TRAF1) gene, complement component 5 (C5) gene, and rheumatic heart disease (RHD). We observed no association with RHD for the five tagging single nucleotide polymorphisms (tSNP) in the C5 gene, the three tSNPs in the TNFAIP3 gene, or the two tSNPs in the TRAF1 gene. However, we determined that the tSNP, rs582757, located at intron_5 of the TNFAIP3 gene, associated with RHD in Chinese Han population. Both the distribution of genotype and allele frequencies differed significantly between case and control subjects (p = 0.001 and p = 0.0004, respectively). The minor C allele reduced the risk of RHD with a per-allele odds ratio of 0.57 (0.42-0.78) for the additive model in univariate analysis (p = 0.000). Under a dominant model, CC/CT carriers had a 0.54-fold reduced risk of RHD (95% confidence interval 0.38-0.75, p = 0.000) than TT carriers. Therefore, we report a new genetic variant (rs582757) in the TNFAIP3 gene that associated with the prevalence of RHD in Chinese Han population. Further genetic and functional studies are required to identify the etiological variants in linkage disequilibrium with this polymorphism.

Self-renewal and chemotherapy resistance of p75NTR positive cells in esophageal squamous cell carcinomas.

BACKGROUND: p75NTR has been used to isolate esophageal and corneal epithelial stem cells. In the present study, we investigated the expression of p75NTR in esophageal squamous cell carcinoma (ESCC) and explored the biological properties of p75NTR+ cells. METHODS: p75NTR expression in ESCC was assessed by immunohistochemistry. p75NTR+ and p75NTR- cells of 4 ESCC cell lines were separated by fluorescence-activated cell sorting. Differentially expressed genes between p75NTR+ and p75NTR- cells were determined by real-time quantitative reverse transcription-PCR. Sphere formation assay, DDP sensitivity assay, 64copper accumulation assay and tumorigenicity analysis were performed to determine the capacity of self-renewal, chemotherapy resistance and tumorigenicity of p75NTR+ cells. RESULTS: In ESCC specimens, p75NTR was found mainly confined to immature cells and absent in cells undergoing terminal differentiation. The percentage of p75NTR+ cells was 1.6%-3.7% in Eca109 and 3 newly established ESCC cell lines. The expression of Bmi-1, which is associated with self-renewal of stem cells, was significantly higher in p75NTR+ cells. p63, a marker identified in keratinocyte stem cells, was confined mainly to p75NTR+ cells. The expression of CTR1, which is associated with cisplatin (DDP)-resistance, was significantly decreased in p75NTR+ cells. Expression levels of differentiation markers, such as involucrin, cytokeratin 13, beta1-integrin and beta4-integrin, were lower in p75NTR+ cells. In addition, p75NTR+ cells generated both p75NTR+ and p75NTR- cells, and formed nonadherent spherical clusters in serum-free medium supplemented with growth factors. Furthermore, p75NTR+ cells were found to be more resistant to DDP and exhibited lower 64copper accumulation than p75NTR- cells. CONCLUSION: Our results demonstrated that p75NTR+ cells possess some characteristics of CSCs, namely, self-renewal and chemotherapy resistance. Chemotherapy resistance of p75NTR+ cells may probably be attributable to decreased expression of CTR1.

[Isolation and identification of cancer stem cells from human esophageal carcinoma].

OBJECTIVE: To isolate and identify cancer stem cells from esophageal carcinoma cells (ECCs) using cell surface marker p75NTR. METHODS: ECCs cell lines were established with ECCs collected from 38 surgically resected specimens. Flow cytometry was used to identify the p75NTR positive cells therein that were isolated then using magnetic activated cell sorting (MACS) method. The growing characteristics in DMEM medium and capability of colony-forming in soft agar of the p75NTR positive cells were evaluated ex vivo with MTT method. p75NTR positive cells of different concentrations were subcutaneously injected into the backs of Balb/c nude mice and PBS was injected into the contralateral back, and then tumorigenesis was observed, 8 weeks later the mice were killed with their tumors taken out to undergo microscopy. RESULTS: Eight ECCs cell lines were established, 6 of which were found to contain 0.32%-3.35% of p75NTR positive cells. The purity of p75NTR positive cells isolated by MACS was up to 90%. MTT result showed that population doubling time of the p75NTR positive cells was (17+/-3) hours, significantly shorter than that of the p75NTR negative cells [(37+/-7) hours, P<0.01]. The colony-forming rate in soft agar of the p75NTR positive cells was (45.9%+/-8.9%), significantly higher than that of the p75NTR negative cells [(3.7%+/-2.1%), P<0.01]. As few as 2000 p75NTR positive cells gave rise to new tumors in xenotransplantation, with a tumorigenic ability 50 times as high as that of the p75NTR negative cells. CONCLUSION: p75NTR positive cells carry some properties of cancer stem cells, such as the ability of self-renewal, differentiation and proliferation and demonstrate higher ability of colony-forming ex vivo and tumorigenesis in vivo.

[Recombinant adeno-associated virus mediated RNA interference of angiogenin expression inhibits cell growth of human lung adenocarcinoma].

OBJECTIVE: To study the inhibition of angiogenin (ANG) expression in human lung squamous cancer cell strain-A549 through adeno-associated virus (AAV)-mediated RNA-interference, and therefore to observe its effect on the growth of cancer cells and tumor formation. METHODS: Recombinant AAV expressing H1-promoter-induced small-interference- RNA (siRNA) targeting ANG (AAV-shANG) was constructed, and then transfected into A549 cells. A549 cells and cells transfected with AAV-Null were used as the control groups. The effects of the reduced expression of ANG by RNAi from AAV-shANG on the growth, formation, reproduction, apoptosis, and microvessel-density of the carcinoma were observed. RESULTS: In vitro experiment showed that AAV-shANG was constructed successfully, There was an significant decrease in the expression of ANG protein 72 h after transfection, compared with the normal A459 cells and AAV-Null cells (P < 0.01). Cell cycle analysis showed that the proliferation index (PI) of normal A549 cells, AAV-Null cells and AAVshANG cells were 0.32 +/- 0.29, 0.35 +/- 0.38 and 0.31 +/- 0.43, respectively. There was no statistic difference in the PIs among the 3 groups (P > 0.05). In vivo experiment using thymus-defect mice showed that, there was an remarkable reduction in the mass and volume of tumors in AAV-shANG transfected group, compared to the control groups. Microvessel-density was 9.4 +/- 1.5, 9.8 +/- 2.1 and 5.7 +/- 1.9, respectively in the 3 groups, a statistic difference among the AAV-shANG-transfected group, the normal A549 group and the AAV-Null transfected group. The percentages of apoptotic cells in each group were (7.7 +/- 3.1)%, (8.5 +/- 5.4)%, (17.1 +/- 8.6)%, respectively, the experimental group being higher than those of the control groups. Positive rates of PCNA were (84.8 +/- 9.7)%, (85.8 +/- 9.8)%, and (70.4 +/- 10.1)%, respectively, the AAV-shANG transfected cancer cells showing a lower PCNA index than the control groups. CONCLUSION: AAV-mediated expression of siRNA could reduce the expression of ANG in cancer cells, significantly enough to inhibit cell proliferation, promote cell apoptosis and inhibit tumor growth.

Therapeutic potential of angiogenin modified mesenchymal stem cells: angiogenin improves mesenchymal stem cells survival under hypoxia and enhances vasculogenesis in myocardial infarction.

BACKGROUND: To examine the effects of angiogenin modified mesenchymal stem cells (MSCs) on ventricular remodeling and cardiac function in a rat model of acute myocardial infarction. METHODS: MSCs were transfected with adenoviral vectors carrying either angiogenin (MSC(AdANG)) or EGFP (MSC(AdEGFP)). Angiogenin gene amplification, protein expression and cell death were assayed after hypoxic treatment. DiI labeled MSC(AdANG) and MSC(AdEGFP) were injected into infracted heart. Six weeks after cell transplantation, echocardiography and histological study were performed. RESULTS: After hypoxia treatment, angiogenin modified MSCs effectively expressed angiogenin for at least 14 days. The death of MSC(AdANG) was one-third of MSCAd(EGFP), and 50% of untreated MSCs. In the infracted myocardium, the number of DiI labeling cells in MSC(AdANG) group with high angiogenin expression was three-fold that in MSC(AdEGFP) group. Echocardiograms suggested that angiogenin modified MSCs significantly improved left ventricular (LV) systolic and diastolic function. Histological study confirmed that ventricular remodeling was attenuated significantly in MSC(AdANG) group. Furthermore, vasculogenesis was enhanced significantly in MSC(AdANG) group as measured by both factor VIII and alpha-SMA staining. CONCLUSION: Angiogenin modified MSCs enhanced the tolerance of engrafted MSCs to hypoxia injury in vitro and improved their viability in infracted hearts, thus helping preserve the LV contractile function and attenuate LV remodeling through vasculogenesis.

Angiopoietin-1 targeted RNA interference suppresses angiogenesis and tumor growth of esophageal cancer.

AIM: To determine the inhibitory effect of the adenovirus-based angiopoietin-1 (Ang-1) targeted small interfering RNA expression system (Ad/Ang-1si) on the expression of the Ang-1 gene, cell growth and apoptosis in human esophageal cancer cell line Eca109. METHODS: siRNA-expressing adenovirus targeting Ang-1 gene was constructed using the Ad Easy System. Cultured Eca109 cells were transfected with Ad/Ang-1si (Eca109/Ang-1si), and Ad/si was used to infect Eca109 cells as control (Eca109/si). Ang-1 gene expression and concentration was determined with RT-PCR and ELISA, respectively. Human umbilical vein endothelial cell (HUVEC) migration and proliferation were analyzed. After s.c. injection into athymic nu/nu mice, the tumor growth, vessel density and apoptosis of each group was also determined. RESULTS: HUVEC migration induced by conditioned medium from Ang-1si-transfected Eca109 cells was significantly less than that induced by conditioned medium from Eca109 cells and control adenovirus-transfected Eca109 cells. Furthermore, after s.c. injection into athymic nu/nu mice, the tumor growth and cell apoptosis of Ad/Ang-1si -expressing Eca109 cells was significantly lower than that of parental or control adenovirus-transfected cells. Vessel density assessed by CD31 immunohistochemical analysis and Ang-1 expression by RT-PCR were also decreased. CONCLUSION: The targeting Ang-1 may provide a therapeutic option for esophageal cancer.

[Isoflurane pretreatment reduced liver injury induced by ischemia/reperfusion combined with lipopolysaccharide in rats].

OBJECTIVE: To investigate the effect of lipopolysaccharide (LPS) on ischemia/reperfusion (I/R) injury of liver and the protective effect of isoflurane (ISO) pretreatment on such injury in rat. METHODS: Thirty-two male Sprague-Dawley(SD) rats were randomly assigned to 4 groups: Sham group, only receive anesthesia and laparotomy; I/R group; I/R+LPS group, with 1 hour of hepatic ischemia and 4 hours of reperfusion, and LPS was given at the beginning of reperfusion; ISO group, received ISO pretreatment for 0.5 hour, then 1 hour of hepatic ischemia followed by 4 hours of reperfusion and LPS given at the beginning of reperfusion. The pathological changes in the liver tissue were assessed. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), the myeloperoxidase (MPO) activity in liver tissue, hepatic and serum tumor necrosis factor-alpha (TNF-alpha) were determined. RESULTS: Compared with Sham group, ALT, AST, TNF-alpha in serum and MPO activity in liver tissue, hepatic and serum TNF-alpha were increased significantly in all injury groups (all P<0.01). Compared with ISO group alone, hepatic I/R combined with LPS resulted in severer liver injury, with the levels of ALT, AST in serum, MPO activity in the liver tissue, and hepatic and serum TNF-alpha level were all increased (all P<0.05). Compared with I/R+LPS group, both the liver injury and inflammatory reaction were significantly reduced in I/R group (P<0.05 or P<0.01). CONCLUSION: LPS injection during reperfusion results in severer liver injury and inflammatory reaction after hepatic I/R in rats. ISO pretreatment for 30 minutes might reduce the inflammatory reaction and live injury induced by hepatic I/R combined with LPS.

[Effects of Xuefu Zhuyu Capsule on endothelin-1 release in myocardium and vascular endothelium and nitric oxide/nitric oxide synthase system of swines after acute myocardial infarction and reperfusion].

OBJECTIVE: To observe the effects of Xuefu Zhuyu Capsule (XFZYC), a compound traditional Chinese herbal medicine, on endothelin-1 (ET-1) release in myocardium and vascular endothelium and nitric oxide (NO)/nitric oxide synthase (NOS) system of swines after acute myocardial infarction (AMI) and reperfusion, and to explore the action mechanisms of XFZYC in improving the endothelium function. METHODS: Forty-five Yorkshire swines were randomized into 3 groups: sham-operated group, untreated group and XFZYC-treated group. A Yorkshire swine model of reperfusion in AMI was established by ligation of left anterior descending coronary artery for 90 min followed by 2 h relaxation. The content of serum ET-1 and NO was measured by radioimmunoassay before and after AMI and after reperfusion, respectively. Twenty-four hours after operation, all Yorkshire swines underwent diagnostic coronary angiography to delineate coronary arteries. The expressions of ET-1 and endothelial nitric oxide synthase (eNOS) in myocardial tissue of ischemic area were quantified with Western blotting. Microvessel density of the implanting sites was assessed by using HE staining. RESULTS: Compared with the untreated group, the levels of serum ET-1 after AMI and reperfusion were significantly decreased in XFZYC-treated group (P<0.01), while the NO levels after AMI and reperfusion in XFZYC-treated group were significantly increased (P<0.01). There was no significant difference in diagnostic coronary angiography between XFZYC-treated group and untreated group (P=0.253). Western blotting showed that the level of ET-1 in ischemic area in XFZYC-treated group was lower than that in the untreated group (P<0.01), while the eNOS protein expression in XFZYC-treated group was higher than that in the untreated group (P<0.01). The results of HE staining and microvessel density analysis of the implanting sites all showed that the degree of telangiectasis was reduced, the cardiac muscle damage was improved, and the density of capillaries was increased obviously in XFZYC-treated group as compared with the untreated group. CONCLUSION: The endothelium injury may be one of the important mechanisms for no-reflow phenomenon. XFZYC may reduce the no-reflow by protecting endothelium cells.

Does PGA external stenting reduce compliance mismatch in venous grafts?

BACKGROUND: Autogenous vein grafting is widely used in regular bypassing procedures. Due to its mismatch with the host artery in both mechanical property and geometry, the graft often over expands under high arterial blood pressure and forms a step-depth where eddy flow develops, thus causing restenosis, fibrous graft wall, etc. External stents, such as sheaths being used to cuff the graft, have been introduced to eliminate these mismatches and increase the patency. Although histological and immunochemical studies have shown some positive effects of the external stent, the mechanical mismatch under the protection of an external stent remains poorly analyzed. METHODS: In this study, the jugular veins taken from hypercholesterolemic rabbits were transplanted into the carotid arteries, and non-woven polyglycolic acid (PGA) fabric was used to fabricate the external stents to study the effect of the biodegradable external stent. Eight weeks after the operation, the grafts were harvested to perform mechanical tests and histological examinations. An arc tangent function was suggested to describe the relationship between pressure and cross-sectional area to analyse the compliance of the graft. RESULTS: The results from the mechanical tests indicated that grafts either with or without external stents displayed large compliance in the low-pressure range and were almost inextensible in the high-pressure range. This was very different from the behavior of the arteries or veins in vivo. The data from histological tests showed that, with external stents, collagen fibers were more compact, whilst those in the graft without protection were looser and thicker. No elastic fiber was found in either kind of grafts. Furthermore, grafts without protection were over-expanded which resulted in much bigger cross-sectional areas. CONCLUSION: The PGA external extent contributes little to the reduction of the mechanical mismatch between the graft and its host artery while remodeling develops. For the geometric mismatch, it reduces the cross-section area, therefore matching with the host artery much better. Although there are some positive effects, conclusively the PGA is not an ideal material for external stent.

Primary triple valve surgery for advanced rheumatic heart disease in Mainland China: a single-center experience with 871 clinical cases.

BACKGROUND: Triple valve surgery (TVS) is still of choice for advanced rheumatic heart disease (RHD), which has been associated with reported poor early and late outcomes. We describe the short- and long-term results after TVS in last two decades in Mainland China. METHODS: From January 1985 to January 2005, a total of 871 patients (217 men, 654 women), with mean age of 42+/-11 years, underwent primary TVS for isolated advanced RHD. All patients received replacement procedures in mitral and aortic position (845 mechanical, 26 bioprosthetic), and 840 patients received repair procedures and the other 31 received replacement procedures in tricuspid position (9 mechanical, 22 bioprosthetic). Preoperative, perioperative, and postoperative data were retrospectively analyzed and risk factors affecting early and late survival were evaluated. RESULTS: The 30-day hospital mortality was 8% (n=71). Presence of ascites, New York Heart Association (NYHA) class IV and lower left ventricular ejection fraction (LVEF) were identified as independent risk factors for hospital mortality. Overall long-term survival rate was 71%+/-3% at 5 years, and 59%+/-5% at 10 years. The cardiac survival rate was 75%+/-3% at 5 years and 63%+/-4% at 10 years. The event-free survival rate at 5 years and 10 years was 61%+/-6% and 41%+/-13%, respectively. Multivariate analysis revealed advanced age, NYHA class IV and lower LVEF were associated with increased late mortality. The freedom from thromboembolism and anticoagulation-related hemorrhage at 10 years was 90%+/-4% and 81%+/-5%, respectively. Of the 508 patients still alive, 376 (74%) were in NYHA class I and II. CONCLUSIONS: Primary TVS for advanced RHD appears to offer satisfactory short- and long-term results with excellent symptomatic improvement. Cardiac-related late mortality following TVS may be improved by early surgical treatment before NYHA class IV or deterioration of LVEF occurs.

Effect of external stents on prevention of intimal hyperplasia in a canine vein graft model.

BACKGROUND: External stents have been used to reduce intimal hyperplasia of vein grafts. The aim of the present study was to define the size of an external stent appropriate for a particular graft by comparing vein grafts with different sizes of external stents. METHODS: A series of paired trials was performed to compare femoral vein grafts with different sizes of external stents, where 30 modeled canines were equally divided into three groups: 6-mm external stent vs non-stent control, 4-mm vs 6-mm external stent, and 4-mm vs 8-mm external stent. At day 3 after operation, color Doppler flow imaging (CDFI) was done to observe blood flow in the lumen. Four weeks later, CDFI was re-checked and the veins were harvested, stained and measured. RESULTS: All grafts were patent without formation of thrombosis. External stents significantly reduced intimal thickness of the vein grafts with a 6-mm external stent compared with the vein grafts without external stents (P < 0.05). The vein grafts with the 4-mm external stent had similar intimal, medial and adventitial thicknesses compared with those with the 6-mm external stent and the 8-mm external stent. CONCLUSIONS: External stents can reduce intimal hyperplasia of vein grafts. Stents of different diameters exert the similar effect on prevention of intimal hyperplasia.

[Expression of mineralocorticoid receptor and 11-beta-hydroxysteroid dehydrogenase type 2 in human atria during chronic atrial fibrillation: study of 25 cases].

OBJECTIVE: To investigate the mRNA and protein expression of mineralocorticoid receptor (MR) and 11-beta-hydroxysteroid dehydrogenase type 2 (11betaHSD2), which plays a crucial role in the human heart to confer specificity on MR, in patients with chronic atrial fibrillation. METHODS: Twenty-five patients of rheumatic heart valve disease, 12 with sinus rhythm, and 13 with chronic atrial fibrillation for 6 months or over, underwent transthoracic echocardiography and mitral/aortic valve replacement operation during which right atrial lateral wall tissue samples were obtained and left atrial lateral wall tissue samples were obtained from 14 of them in addition. Realtime quantitative PCR was used to determine the mRNA expression of MR and 11betaHSD2 and Western blotting was employed to detect the protein expression of MR and 11betaHSD2 in the atrial myocardium. RESULTS: The left atrial diameters increased markedly in the atrial fibrillation group as compared to the sinus rhythm group (P < 0.01). The mRNA expression of MR in the right atrium of the patients with atrial fibrillation was 5.37 +/- 1.15, significantly higher than that of the patients with sinus rhythm (2.67 +/- 1.09, P < 0.01), the mRNA expression of MR in the left atrium of the patients with atrial fibrillation was 5.19 +/- 1.14, significantly higher than that of the patients with sinus rhythm (270 +/- 0.82, P < 0.01). The mRNA expression of 11betaHSD2 in the right atrium of the patients with atrial fibrillation was 0.86 +/- 0.14, significantly higher than that of the patients with sinus rhythm (0.33 +/- 0.12, P < 0.01), and the mRNA expression of 11betaHSD2 in the left atrium of the patients with atrial fibrillation was 0.95 +/- 0.15, significantly higher than that of the patients with sinus rhythm (0.37 +/- 0.10, P < 0.01). The protein expression of MR in the right atrial tissue of the patients with atrial fibrillation was 1.65 +/- 0.72, significantly higher than that of the patients with sinus rhythm (0.86 +/- 0.33, P < 0.01); and the protein expression of MR in the left atrial tissue of the patients with atrial fibrillation was 1.72 +/- 0.62, significantly higher than that of the patients with sinus rhythm (0.97 +/- 0.37a, P < 0.05). The protein expression of 11betaHSD2 in the right atrial tissue of the patients with atrial fibrillation was 1.18 +/- 0.64, significantly higher than that of the patients with sinus rhythm (0.71 +/- 0.21, P < 0.05); and the protein expression of 11betaHSD2 in the left atrial tissue of the patients with atrial fibrillation was 1.36 +/- 0.58, significantly higher than that of the patients with sinus rhythm (0.85 +/- 0.15, P < 0.05). The mRNA expression and protein expression of MR and 11betaHSD2 were not significantly different between the left atria and right atria both in the fibrillation and sinus groups (all P > 0.05). CONCLUSION: The mRNA expression and protein expression of MR and 11betaHSD2 are upregulated in atrial fibrillation and aldosterone antagonists may be effective to arrest the development of sustained atrial fibrillation.