Viabahn Stent Graft for the Endovascular Treatment of Occlusive Lesions in the Femoropopliteal Artery: A Retrospective Cohort Study with 4-Year Follow-Up.

BACKGROUND: The polytetrafluoroethylene-covered Viabahn stent may be effective for the endovascular treatment of patients with femoropopliteal artery occlusive lesions. However, the long-term efficacy of Viabahn stent remains unclear. The aim of the study is to evaluate the long-term patency of Viabahn stent grafts in patients with occlusive lesions in the femoropopliteal artery. METHODS: Consecutive patients with occlusive lesions in the femoropopliteal artery who had been treated with Viabahn stent grafts during the period from June 2013 to December 2016 at our center were retrospectively included. Accumulative incidences of primary patency and secondary patency were estimated by Kaplan-Meier survival analysis, and the predictors of primary patency were evaluated by Cox regression analysis. RESULTS: A total of 66 patients underwent successful endovascular treatment and were included in the study. Endovascular treatment with a Viabahn stent was associated with a complication rate of 9.1% and a 30-day mortality rate of 1.5%. Sixty-one patients were followed for a mean duration of 29.5 months. The 1-year, 2-year, 3-year, and 4-year primary patency rates were 81.7%, 74.7%, 67.6%, and 58.9%, respectively. The secondary patency rates were 94.9%, 92.9%, 90.1%, and 90.1%, respectively. The overall major amputation rate was 5.0%. The results of multivariate Cox regression analyses showed that stent location was the only independent predictor of primary patency (P = 0.001). Implantation of a Viabahn stent above the knee, compared with implantation below the knee, was associated with a higher rate of primary patency. CONCLUSIONS: The Viabahn stent graft is associated with a satisfactory rate of long-term patency for the endovascular treatment of occlusive lesions in the femoropopliteal artery, especially for those located above the knee.

ARHGAP18 Protects Against Thoracic Aortic Aneurysm Formation by Mitigating the Synthetic and Proinflammatory Smooth Muscle Cell Phenotype.

RATIONALE: Thoracic aortic aneurysm (TAA) is a potentially lethal condition, which can affect individuals of all ages. TAA may be complicated by the sudden onset of life-threatening dissection or rupture. The underlying mechanisms leading to TAA formation, particularly in the nonsyndromal idiopathic group of patients, are not well understood. Thus, identification of new genes and targets that are involved in TAA pathogenesis are required to help prevent and reverse the disease phenotype. OBJECTIVE: Here we explore the role of ARHGAP18, a novel Rho GAP expressed by smooth muscle cells (SMCs), in the pathogenesis of TAA. METHODS AND RESULTS: Using human and mouse aortic samples, we report that ARHGAP18 levels were significantly reduced in the SMC layer of aortic aneurysms. Arhgap18 global knockout (Arhgap18-/-) mice exhibited a highly synthetic, proteolytic, and proinflammatory smooth muscle phenotype under basal conditions and when challenged with angiotensin II, developed TAA with increased frequency and severity compared with littermate controls. Chromatin immunoprecipitation studies revealed this phenotype is partly associated with strong enrichment of H3K4me3 and depletion of H3K27me3 at the MMP2 and TNF-α promoters in Arhgap18-deficient SMC. We further show that TAA formation in the Arhgap18-/- mice is associated with loss of Akt activation. The abnormal SMC phenotype observed in the Arhgap18-/- mice can be partially rescued by pharmacological treatment with the mTORC1 inhibitor rapamycin, which reduces the synthetic and proinflammatory phenotype of Arhgap18-deficient SMC. CONCLUSION: We have identified ARHGAP18 as a novel protective gene against TAA formation and define an additional target for the future development of treatments to limit TAA pathogenesis.

Downregulation of Pin1 in human atherosclerosis and its association with vascular smooth muscle cell senescence.

OBJECTIVE: Pin1 is prevalently overexpressed in human cancers and implicated to regulate cell growth and apoptosis. Thus far, however, no role for Pin1 has been described in modulating vascular smooth muscle cell (VSMC) senescence. METHODS: Immunohistochemistry and Western blotting were used to assess Pin1 protein level in human normal and atherosclerotic tissues. ß-galactosidase staining, cumulative population doubling level, telomerase activity, and relative telomere length measurement were used to confirm VSMC senescence. The expressions of Pin1 and other genes involved in this research were analyzed by quantitative reverse-transcription polymerase chain reaction and Western blotting in VSMCs. Apolipoprotein E gene-deleted mice (ApoE-/-) fed a high-fat diet were treated with juglone or 10% ethanol, respectively, for 3 weeks. The extent of atherosclerosis was evaluated by Oil Red O, Masson trichrome staining, and immunohistology. RESULTS: Pin1 protein level decreased in human atherosclerotic tissues and VSMCs, synchronously with increased VSMC senescence. Adenoviral-mediated Pin1 overexpression rescued cellular senescence in atherosclerotic VSMCs, with concurrent down-regulation of P53, p21, growth arrest and DNA-damage-inducible protein 45-alpha (Gadd45a), phosphorylated retinoblastoma (p-pRb), p65 and upregulation of cyclin subfamilies (cyclin B, D, and E), and cyclin-dependent kinase subfamilies (2, 4, and 6), whereas Pin1 knockdown resulted in the converse effects, indicating that VSMC senescence mediated by Pin1 is an integrated response to diverse signals. In vivo data from ApoE-/- mice showed that treatment of juglone led to accelerated atherosclerosis development. CONCLUSIONS: Altogether this work supports a role for Pin1 as a vital modulator of VSMC senescence, thereby providing a novel target for regulation and control of atherosclerosis.

[Molecular mechanisms of antithrombin deficiency caused by novel double heterozygous mutations].

OBJECTIVE: To explore the molecular mechanisms of antithrombin (AT) deficiency caused by novel double heterozygous mutations. METHODS: Wild-type and mutant AT cDNA expression plasmids (ATwt, AT-c.134G > A, AT-c.342T > G, AT-c.134G > A and AT-c.342T > G) were transfected into HEK293T cells. Western blot was used to detect the AT:Ag in cell lysates. Homology was used to reestablish 3-D spatial structure of AT. Laser confocal assay was utilized to analyze the distribution of AT in endoplasmic reticulum (ER). RESULTS: Compared to the wild-types, the AT expression of HEK293T cells sharply increased when they were transfected by AT-c.342T > G or AT-c.134G > A and c.342T > G. Homology modeling showed that the mutation (AT-c.342T > G) caused a decreased distance between Arg and surrounding bases as Arg's side chain was significantly longer than Ser's. The mutation of 13th base pair decreases the distance between AT and heparin. Laser confocal assay showed that the AT protein concreted in HEK293T cells when they were transfected by mutant plasmids (AT-c.134G > A and c.342T > G) and aggregated in ER. CONCLUSIONS: The main molecular mechanism of AT deficiency in this pedigree is the disturbed AT secretion as a result of the mutation of AT-c.342T > G.

[Subintimal arterial flossing with antegrade-retrograde intervention technique to treat long-segment occlusion of peripheral artery].

OBJECTIVE: To discuss the technique details of subintimal arterial flossing with antegrade-retrograde intervention (SAFARI) to improve technical success in the treatment of chronic total occlusions (CTO) diseases in lower extremity when there is failure to reenter the distal true lumen. METHODS: Between May 2009 and Aug 2010, 15 patients underwent endovascular recanalization with SAFARI technique. There were 8 male and 7 female patients with a mean age of 74.9 years. There were 3 patients with severe claudication (Rutherford category 3) and 12 patients with critical limb ischemia (Rutherford category 4 to 6). The clinical and follow-up data of these patients were analyzed retrospectively. RESULTS: Fourteen patients were treated with SAFARI technique successfully. The technique success rates were 93.3%. The mean ankle brachial index increased from 0.39 to 0.83.Symptoms were relieved in 86.6% patients, Ulcer were healed in 93.3%patients. CONCLUSIONS: SAFARI technique is a safe and effective method in treating CTO diseases, when it is failure to renter the distal true lumen with subintimal angioplasty technique.

C1q/TNF-related protein 9 decreases cardiomyocyte hypoxia/reoxygenation-induced inflammation by inhibiting the TLR4/MyD88/NF-κB signaling pathway.

C1q/TNF-related protein 9 (CTRP9) acts as an adipokine and has been reported to exert numerous biological functions, such as anti-inflammatory and anti-oxidative stress effects, in ischemic heart disease. In the present study, the role of CTRP9 in neonatal rat cardiomyocytes (NRCMs) following hypoxia/reoxygenation (H/R) and the underlying mechanism was investigated. Adenoviral vectors containing CTRP9 or green fluorescent protein were transfected into NRCMs. A H/R model was constructed 2 days after transfection by 2 h incubation under hypoxia followed by 4 h of reoxygenation. Lactate dehydrogenase (LDH), creatine kinase (CK) and CK-myocardial band (CK-MB) levels were detected by a biochemical analyzer using biochemical kits. In addition, cell viability was detected using trypan blue staining to determine the extent of cell injury. Inflammatory cytokines TNF-α, IL-6 and IL-10 were measured by ELISA. Western blotting and reverse transcription-quantitative PCR were used to evaluate the expression levels of CTRP9, toll-like receptor 4 (TLR4), myeloid differentiation primary response (MyD88) and NF-κB. The DNA binding activity of NF-κB was also detected using an electrophoretic mobility shift assay. The results indicated that transfection with adenoviral vectors containing CTRP9 could markedly enhance CTRP9 expression. CTRP9 overexpression increased cell viability and decreased the release of LDH, CK and CK-MB. In addition, CTRP9 overexpression reduced TNF-α and IL-6 levels whilst increasing IL-10 levels, but decreased the expression of TLR4, MyD88 and NF-κB. Furthermore, the DNA binding activity of NF-κB under H/R was also decreased by CTRP9 overexpression. In conclusion, the results of the present study suggested that CTRP9 could protect cardiomyocytes from H/R injury, which was at least partially due to the inhibition of the TLR4/MyD88/NF-κB signaling pathway to reduce the release of inflammatory cytokines.

Inhibition of peptidyl-prolyl cis/trans isomerase Pin1 induces cell cycle arrest and apoptosis in vascular smooth muscle cells.

This study was undertaken to determine the in vitro effect of lentivirus-mediated siPin1 on cell cycle and apoptosis of vascular smooth muscle cells (VSMCs). Further we sought to provide insight into the mechanisms behind these processes. Human umbilical artery smooth muscle cells (HUASMCs) were transfected with lentiviral siPin1. Real-time RT-PCR and Western blotting were used to examine Pin1 mRNA and protein expression. MTT and [(3)H]thymidine incorporation assays were employed to observe cell proliferation status. The apoptotic rate and cell cycle were analyzed by Hoechst33258 staining and flow cytometry. Finally we measured the expression of cyclin D1, beta-catenin, CDK4, cytochrome c, procaspase-3, cleaved caspase-3, procaspase-9, cleaved caspase-9, Bcl-2, Bax, STAT3, phosphorylated STAT3 and VEGF in lentiviral siPin1 infected VSMCs. Lentivirus-mediated siPin1 effectively diminished endogenous Pin1 expression in VSMCs resulting in cell cycle arrest and enhancement of apoptosis. This was accompanied by downregulation of cyclin D1, beta-catenin, CDK4, increase of Bax/Bcl-2 ratio, release of cytochrome c, and activation of caspase-3 and -9. We concluded that this effect was mediated, at least in part, via the beta-catenin/cyclin D1/CDK4 cascade, and that the mitochondrial pathway was responsible for VSMC apoptosis in the absence of Pin1. Our observations raised the possibility that Pin1 might be a potential therapeutic target to prevent stenosis.

Drug packaging and delivery using perfluorocarbon nanoparticles for targeted inhibition of vascular smooth muscle cells.

AIM: To investigate the in vitro release profile of drugs encapsulated within perfluorocarbon (PFC) nanoparticles (NPs) and their ability to inhibit the activity of vascular smooth muscle cells (SMCs). METHODS: Dexamethasone phosphate (DxP) or dexamethasone acetate (DxA) was encapsulated into PFC nanoparticles using a high-pressure homogenous method. The morphology and size of the NPs were examined using scanning electron microscopy (SEM) and a laser particle size analyzer. Drug loading and in vitro release were assessed by high-performance liquid chromatography (HPLC). The impact of NP capsules on SMC proliferation, migration and apoptosis in vitro was assessed using cell counting kit-8, transwell cell migration and flow cytometry assays. RESULTS: The sizes of DxP-NPs and DxA-NPs were 224+/-6 nm and 236+/-9 nm, respectively. The encapsulation efficiency (EE) of DxP-NPs was 66.4%+/-1.0%, with an initial release rate of 77.2%, whereas the EE of DxA-NPs was 95.3%+/-1.3%, with an initial release rate of 23.6%. Both of the NP-coated drugs could be released over 7 d. Human umbilical artery SMCs were harvested and cultured for four to six passages. Compared to free DxP, SMCs treated with tissue factor (TF)-directed DxP-NPs showed significant differences in the inhibition of proliferation, migration and apoptosis (P<0.05). CONCLUSION: The results collectively suggest that PFC nanoparticles will be beneficial for targeted drug delivery because of the sustained drug release and effective inhibition of SMC proliferation and migration.

Lentivirus-mediated RNA interference targeting STAT4 inhibits the proliferation of vascular smooth muscle cells.

BACKGROUND: STAT4 is a key transcription factor regulating Th1 development. However, its presence and role in vascular smooth muscle cells (VSMCs) has not been well studied. In the current study, we have utilized lentivirus-mediated shRNA for functional gene knockdown in human umbilical artery smooth muscle cells in order to access the potential role of STAT4 in VSMC growth. METHODS: Cells were isolated from the umbilical arteries of newborns and used at passage 3-5. Recombinant lentivirus producing STAT4 siRNA was prepared. Protein and mRNA expression of STAT4 and relevant genes were examined by Western blot, ELISA, and quantitative RT-PCR analysis, and the effects of the lentivirus on cell growth and apoptosis were determined using MTT assay and flow cytometry, respectively. RESULTS: Lentivirus-mediated RNAi effectively reduced endogenous STAT4 expression and downregulation of STAT4 in VSMCs and significantly reduced VSMC growth rate in vitro. We found that STAT4 knockdown led to impaired pSTAT4 protein expression. SOCS-3 as well as MCP-1 production were also markedly decreased, consistent with the suppression of STAT4 expression. CONCLUSIONS: Results from our study suggest that STAT4 may play a role in VSMC proliferation, and thus is a novel therapeutic target for neointima formation following vascular injury, e.g., post-angioplasty restenosis.

[Effect of different transpulmonary pressures guided mechanical ventilation on respiratory and hemodynamics of patients with ARDS: a prospective randomized controlled trial].

OBJECTIVE: To assess the effect of different transpulmonary pressures (Ptp) guided mechanical ventilation (MV) on respiratory function and hemodynamics parameters of patients with acute respiratory distress syndrome (ARDS), and to find out a more optimized Ptp. METHODS: A prospective randomized controlled trial (RCT) was conducted. The ventilated patients with ARDS admitted to Department of Critical Care Medicine (ICU) of Shenzhen Shajing Affiliated Hospital of Guangzhou Medical University and Department of Emergency and Critical Care Medicine (EICU) of Shenzhen Hospital of South Medical University from February 2013 to August 2016 were enrolled. According to random number table method, all patients were divided into control group and observation group. The patients in observation group was subdivided into three subgroups according to the different setting of Ptp, namely Ptp 10, 15, 20 cmH2O (1 cmH2O = 0.098 kPa) subgroups. The patients in all groups received standard treatment in accordance with the international guidelines for ARDS. The patients in control group were ventilated by guidance of ARDSNet, and the patients in observation group were ventilated by guidance of different Ptp. After setting different Ptp at 1, 24, 48 hours in the process of MV, respiratory function parameters of patients in all groups were determined. The hemodynamic parameters were determined by using pulse indicating continuous cardiac output (PiCCO) technology. The duration of MV, length of ICU stay and 28-day mortality were recorded. RESULTS: A total of 67 patients with ARDS were enrolled, among whom 2 patients died within 48 hours, and 1 case was lost to follow-up. Finally, 64 patients completed the study, 43 patients in observation group, and 21 in control group. There were no significant differences in gender composition, age, oxygenation index (PaO2/FiO2) within 4 hours after hospital admission and acute physiology and chronic health evaluation II (APACHE II) score between the two groups, which showed the baseline was equivalent and comparable. The respiratory function and hemodynamic parameters showed no obvious change in control group at different time points of MV; but with the extension of ventilation, the respiratory function was improved significantly in observation group, and the gradually rising of Ptp had obvious adverse effects on hemodynamics parameters. Compared with control group, at 48 hours of ventilation after setting Ptp, the respiratory function in Ptp 20 cmH2O subgroup was improved significantly, PaO2/FiO2, arterial partial pressure of carbon dioxide (PaCO2), positive end-expiratory pressure (PEEP), airway platform pressure (Pplat), and lung compliance (Cst) were significantly increased [PaO2/FiO2 (mmHg, 1 mmHg = 0.133 kPa): 220.9±30.8 vs. 178.5±42.9, PaCO2 (mmHg): 55.1±7.6 vs. 38.6±4.8, PEEP (cmH2O): 24.7±4.8 vs. 6.6±2.2, Pplat (cmH2O): 34.4±3.7 vs. 20.7±3.5, Cst (mL/cmH2O): 23.8±3.6 vs. 13.1±4.6; all P < 0.05], and extravascular lung water index (ELWI) was significantly decreased (mL/kg: 6.8±1.7 vs. 10.8±2.6, P < 0.05), but mean artery pressure (MAP), cardiac index (CI), global end-diastolic volume index (GEDVI) such as hemodynamics parameters were also significantly reduced [MAP (mmHg): 58.8±6.7 vs. 69.7±4.7, CI (mL×s-1×m-2): 46.7±23.3 vs. 73.3±30.0, GEDVI (mL/m2): 633.2±45.2 vs. 702.6±55.7; all P < 0.05]; the PaO2/FiO2, PEEP, Pplat, and Cst in Ptp 10 cmH2O subgroup were significantly increased [PaO2/FiO2 (mmHg): 183.4±45.5 vs. 178.5±42.9, PEEP (cmH2O): 14.4±3.6 vs. 6.6±2.2, Pplat (cmH2O): 25.7±5.6 vs. 20.7±3.5, Cst (mL/cmH2O): 16.2±4.3 vs. 13.1±4.6; all P < 0.05], and ELWI was significantly reduced (mL/kg: 8.7±1.8 vs. 10.8±2.6, P < 0.05), but the MAP, CI and GEDVI showed no significant difference [MAP (mmHg): 65.8±4.6 vs. 69.7±4.7, CI (mL×s-1×m-2): 65.0±35.0 vs. 73.3±30.0, GEDVI (mL/m2): 706.7±54.4 vs. 702.6±55.7; all P > 0.05]. The above illustrated that 10 cmH2O Ptp could act as the same as 20 cmH2O did to improve oxygenation and respiratory function, but had no obvious effect on hemodynamics. Compared with control group, the duration of MV and the length of ICU stay showed no significant differences in Ptp 10 cmH2O and 15 cmH2O subgroups, but those in 20 cmH2O subgroup were significantly shortened [duration of MV (days): 95.5±21.5 vs. 130.8±23.6, length of ICU stay (days): 8.1±2.2 vs. 12.8±2.8, both P > 0.05]. There was no significant difference in 28-day mortality among the groups. CONCLUSIONS: MV guided by Ptp of 10 cmH2O could improve oxygenation and respiratory mechanics, while has less hemodynamic influence. It was a safe and effective cardiopulmonary protection ventilation method.

[Related factor of serum carnitine deficiency and influence of its deficiency on the length of hospital stay in critical ill patients].

OBJECTIVE: To investigate the related factors of serum carnitine deficiency in critical ill patients, and the influence of its deficiency on the length of hospital stay. METHODS: A prospective study was conducted. Critical ill patients with acute physiology and chronic health evaluation II (APACHEII) score>12 admitted to Department of Critical Care Medicine of the First Affiliated Hospital of Sun Yat-sen University from March 2013 to September 2013 were enrolled. Serum carnitine concentration and indexes of organ function were determined, and the tolerance of enteral nutrition within 5 days, the length of hospital stay, the length of intensive care unit (ICU) stay, and the hospital mortality were recorded. The relationship between serum carnitine and indexes mentioned above was analyzed. RESULTS: Thirty critically ill patients were enrolled. Serum carnitine concentration was very low in all critically ill patients, i.e. (8.92 ± 5.05) µmol/L (normal reference value at 43.5 µmol/L) at hospital admission. Serum carnitine concentration in patients with APACHEII score>23 (7 cases) was significantly lower than that in those with APACHEII score 12-23 (23 cases, µmol/L: 5.33 ± 1.72 vs. 10.02 ± 5.24, t=2.300, P=0.001). Serum carnitine concentration in patients with serum total bilirubin(TBil)>19 µmol/L (9 cases) was significantly lower than that in those with TBil≤19 µmol/L (21 cases, µmol/L: 5.54 ± 2.70 vs. 9.84 ± 5.08, t=2.750, P=0.014). Serum carnitine concentration was negatively correlated with the APACHEII score and the TBil (r=-0.387, P=0.035; r=-0.346, P=0.048). During the 5-day observation period, enteral feeding amount [(5 134 ± 1 173) mL] was positively correlated with serum carnitine concentration(r=0.430, P=0.022). In 30 critical patients, the incidence of abdominal distension was 40.0% (12/30), and the serum carnitine concentration of patients with abdominal distension was lower compared with that of patients without abdominal distension (µmol/L: 7.83 ± 4.98 vs. 9.12 ± 5.35, t=0.707, P=0.383). The incidence of diarrhea was 26.7% (8/30), and the serum carnitine concentration of diarrhea patients was lower compared with that of patients without diarrhea (µmol/L: 8.27 ± 5.78 vs. 9.73 ± 4.78, t=0.607, P=0.576). The mean length of hospital stay was (34.72 ± 16.66) days. The serum carnitine concentrations in patients with hospital stay ≥ 45 days (8 cases) were lower compared with those in those <45 days (22 cases, µmol/L: 5.71 ± 3.23 vs. 9.95 ± 5.26, t=1.627, P=0.020). No correlation was found between serum carnitine concentrations and the hospital stay (r=-0.165, P=0.385). The length of ICU stay was (18.60 ± 10.72) days. Serum carnitine concentration in patients with the length of ICU stay>7 days (27 cases) was slightly lower than that in those with the length of ICU stay ≤ 7 days (3 cases, µmol/L: 8.44 ± 5.00 vs. 13.24 ± 3.65, t=1.610, P=0.119). No correlation was found between serum carnitine concentrations and the length of ICU stay (r=-0.019, P= 0.293). In-hospital mortality was 26.67% (8/30). No significant difference in serum carnitine concentrations was found between the death group and the survival group (µmol/L: 12.24 ± 6.52 vs. 7.72 ± 3.91, t=-1.846, P=0.098). No correlation was found between serum carnitine concentrations and in-hospital mortality (r=0.340, P=0.066). CONCLUSIONS: Carnitine deficiency is significant in critically ill patients, and it is correlated with disease severity and serum TBil. The total amount of lenteral feeding was lower, and hospital stay was prolonged in critically ill patients with low serum carnitine level.