Bifunctional collagen fiber/carbon quantum dot fluorescent adsorbent for efficient adsorption and detection of Pb2.

In this work, fluorescent adsorbents that can efficiently detect and remove Pb2+ were developed by integrating the designed amino-modified carbon quantum dots and carboxyl-modified collagen. The adsorption properties of the fluorescent adsorbent were further optimized and analyzed using a series of response surface experiments. The maximum adsorption concentration for Pb2+ was 183 mg.g-1. The adsorption isotherms fit well with the Langmuir model, and the adsorption kinetics fit with the pseudo-second-order model. The emission intensity of the fluorescent adsorbent gradually decreased with the increase of the concentration of Pb2+, and had a good linear correlation. In addition, the mechanism of detection and removal of Pb2+ by fluorescent adsorbents was further demonstrated. The novel three-dimensional structured fluorescent aerogel can be used as a promising adsorbent with good adsorption concentration and sensing ability for Pb2+, which shows great prospects in wastewater.

Effects of TCFA on stent neointimal coverage at 9 months after EXCEL drug-eluting stent implantation assessed by OCT.

BACKGROUND: The aim of this study was to investigate the effects of thin-cap fibroatheromas (TCFAs) on stent neointimal coverage at the 9­month follow-up after EXCEL stent implantation assessed by optical coherence tomography (OCT). METHODS: A total of 93 patients with non-ST elevation acute coronary syndrome (NSTEACS) who underwent EXCEL stent implantation were prospectively enrolled in the study and divided into a TCFA group (n = 47) and a non-TCFA group (n = 46) according to whether EXCEL stents covered the TCFAs. A TCFA was defined as a plaque with lipid content in more than one quadrant and fibrous cap thickness measuring less than 65 µm. The effect of TCFAs on stent neointimal coverage at the 9­month follow-up after stent implantation was evaluated by OCT. The primary study endpoints were the incidence of neointimal uncoverage and stent malapposition. RESULTS: At the 9­month follow-up, the minimal lumen diameter of the TCFA group tended to be smaller (2.8 ± 0.8 vs. 2.1 ± 0.8, p = 0.08) and the diameter of stenosis in the TCFA group tended to be larger (15.1 ± 10.3% vs. 26.3 ± 15.1%, p = 0.08) than those in the non-TCFA group. The mean intimal thickness of the TCFA group was significantly lower than that of the non-TCFA group (67.2 ± 35.5 vs. 145.1 ± 48.7, p < 0.001). The uncovered struts (10.1 ± 9.7 vs. 4.8 ± 4.3, p = 0.05) and malapposed struts (2.1 ± 4.7 vs. 0.3 ± 0.5, p = 0.003) in the TCFA group were more significant than those in the non-TCFA group. Multivariate analysis showed that TCFAs and lesion types were independent predictors of incomplete neointimal coverage (p < 0.05), and lesion types were independent predictors of stent malapposition (p < 0.05). CONCLUSION: In patients with NSTEACS, TCFAs delayed endothelium coverage at 9 months after stent implantation, and TCFAs were independent predictors of incomplete neointimal coverage of the stent.

Rare c-KIT c.1926delA and c.1936T>G Mutations in Exon 13 Define Imatinib Resistance in Gastrointestinal Stromal Tumors and Melanoma Patients: Case Reports and Cell Experiments.

Background: Target therapies play more and more important roles in gastrointestinal stromal tumors (GISTs) and melanoma with the advancement of clinical drugs that overcome the resistance caused by gene mutations. c-KIT gene mutations account for a large portion of GIST patients, which are known to be sensitive or resistant to tyrosine kinase inhibitors. However, the role rare mutations play in drug efficacy and progression-free duration remains elusive. Methods: Two rare mutations were identified using Sanger sequencing from the GIST and melanoma cases. Cell experiments were further carried out to demonstrate their role in the imatinib resistance. Results: c-KIT c.1926delA p.K642S*FS mutation in primary and recurrent GIST patients and c-KIT c.1936T>G p.Y646D point mutation in melanoma patients in exon 13 were first demonstrated to be novel targets resistant to imatinib agent. Conclusion: c-KIT mutations c.1926delA and c.1936T>G in exon 13 are clinically significant targets that exhibit resistance to imatinib. This study provides guidance to GIST and melanoma treatments.

Optical coherence tomography: evaluating the effects of stent boost subtract imaging on stent underexpansion in STEMI patients.

BACKGROUND: To evaluate the effect of stent boost subtract (SBS) imaging on stent underexpansion during percutaneous coronary intervention (PCI) in patients with acute ST-segment elevation myocardial infarction (STEMI) by optical coherence tomography (OCT). METHODS: One hundred thirty-eight STEMI patients who underwent drug-eluting stent (DES) implantation were prospectively recruited and divided into the SBS group (69 cases) and the CAG group (69 cases) according to whether SBS was used to guide PCI. Finally, OCT was performed on all enrolled patients, and the OCT results were used as the gold standard to evaluate the impact of standard SBS technology on stent underexpansion immediately after DES implantation. RESULTS: SBS identified 51 patients (24%) with stent underexpansion while OCT identified 56 patients (27.2%). SBS has a sensitivity of 80%, a specificity of 96%, a positive predictive value of 88%, and a negative predictive value of 93% for identifying stent underexpansion. CONCLUSION: Compared with OCT, SBS technology is a rapid stent imaging evaluation method that can accurately quantify the stent expansion level and is time-saving and economical.

Correlation between dual-axis rotational coronary angiography and intravascular ultrasound in a coronary lesion assessment.

The purpose of this study was to evaluate the accuracy of dual-axis rotational coronary angiography (DARCA) for coronary lesion assessment by directly comparing with intravascular ultrasound (IVUS). From October 2014 to December 2015, 40 patients (58 lesions) who had undergone both DARCA and IVUS were included in the image analysis. The minimum lumen diameter (MLD), lesion length, reference vessel diameter (RVD) and percent diameter stenosis at the same lesion, were identified and assessed. Significant correlation with IVUS was found for DARCA in either lesion length (r = 0.90, P < 0.001) or RVD (r = 0.81, P < 0.001) comparison. DARCA had fair correlation with IVUS for both MLD (r = 0.65, P < 0.001) and diameter stenosis (r = 0.48, P < 0.001). From the Bland-Altman plots, there was a good agreement between DARCA and IVUS regarding MLD (mean difference: -0.23 mm, 95 % limits of agreement: -0.96 to 0.50 mm) and RVD (mean difference: -0.15 mm, 95 % limits of agreement: -0.85 to 0.55 mm), while lesser agreement was found on lesion length (mean difference: -3.39 mm, 95 % limits of agreement: -12.63 to 5.85 mm) and diameter stenosis (mean difference: 4.82 %, 95 % limits of agreement: -17.05 to 26.68 %). There is an adequate correlation and agreement between DARCA and IVUS in coronary lesion assessment.

AuNP-Collagen Matrix with Localized Stiffness for Cardiac-Tissue Engineering: Enhancing the Assembly of Intercalated Discs by ß1-Integrin-Mediated Signaling.

A schematic for the mechanism of accelerating the assembly of intercalated discs (IDs) in cardiac myocytes regulated by gold nanoparticles (AuNPs) is presented. AuNPs with local nanoscale stiffness in the substrate activate ß1-integrin signaling, which mediates the activation of integrin-linked kinase (ILK) and its downstream signal kinase by stimulating expression of the transcription factors GATA4 and MEF-2c.

Down-regulation of SIRT3 promotes ovarian carcinoma metastasis.

Distant metastasis and local recurrence are still the major causes for failure of treatment in patients with ovarian carcinoma (OC), making it urgent to further elicit the molecular mechanisms of OC metastasis. Sirtuin-3 (SIRT3), a member of the NAD(+)-dependent Class III histone deacetylases, may function as different role depending on the cell-type and tumor-type. However, the function and mechanism of SIRT3 has been not explored in OC metastasis. Here, we found that SIRT3 was significantly down-regulated in the metastatic tissues and highly metastatic cell line of ovarian cancer. In addition, knockdown of SIRT3 enhanced the migration and invasion in vitro and the liver metastasis in vivo of ovarian cancer cell. By contrast, ectopic overexpression of SIRT3 dramatically suppressed cancer cell metastatic capability. Mechanistically, SIRT3 inhibits epithelial-to-mesenchymal transition (EMT) by down-regulating Twist in ovarian cancer cells. Furthermore, an interaction between SIRT3 and Twist was detected. In conclusion, our results demonstrated that SIRT3 plays a crucial suppressive role in the metastasis of ovarian cancer by down-regulating Twist, and that this novel SIRT3/Twist axis may be valuable to develop new strategies for treating OC patients with metastasis.

Stent boost subtract imaging for the assessment of optimal stent deployment in coronary ostial lesion intervention: comparison with intravascular ultrasound.

Percutaneous coronary intervention (PCI) of ostial lesions is complex and is technically very demanding. Intravascular ultrasound (IVUS) is considered the gold standard method to guide PCI but has several limitations. Stent boost subtract (SBS) imaging is an enhancement of the radiologic edge of the stent by digital management of regular X-ray images. The purpose of this study was to determine the availability of stent enhancement with SBS during ostial PCI by comparison with IVUS.We investigated SBS and IVUS after stent implantation in 58 ostial lesions in 55 patients. SBS and IVUS were performed in all patients to obtain improved stent location and to detect optimal release and deployment. We defined the SBS and IVUS criteria for accuracy of stent location and adequate stent deployment. IVUS findings showed that stent location was generally good. The location was accurate in 48 (82.8%) and inadequate stent deployment was observed in 10 of 58 (17.2%). Eight SBS images showed inadequate stent expansion. SBS predicted inadequate findings of IVUS with 100% specificity and 80% sensitivity, while a significant positive correlation was observed between SBS-MSA and MSA by IVUS with a regression coefficient of 0.95.Imaging techniques have a primary role during ostial PCI. SBS is a simple and quick method that offers several advantages, enabling improved stent location, adequate stent expansion, and optimal apposition of the struts to the wall. SBS imaging could be conventionally used during ostial PCI, especially in centers where IVUS is not used routinely.

Dual-axis rotational coronary angiography can reduce peak skin dose and scattered dose: a phantom study.

The purpose of this study was to evaluate peak skin dose received by the patient and scattered dose to the operator during dual-axis rotational coronary angiography (DARCA), and to compare with those of standard coronary angiography (SA). An anthropomorphic phantom was used to simulate a patient undergoing diagnostic coronary angiography. Cine imaging was applied on the phantom for 2 s, 3 s, and 5 s in SA projections to mimic clinical situations with normal vessels, and uncomplicated and complicated coronary lesions. DARCA was performed in two curved trajectories around the phantom. During both SA and DARCA, peak skin dose was measured with thermoluminescent dosimeter arrays and scattered dose with a dosimeter at predefined height (approximately at the level of left eye) at the operator's location. Compared to SA, DARCA was found lower in both peak skin dose (range: 44%-82%, p < 0.001) and scattered dose (range: 40%-70%, p < 0.001). The maximal reductions were observed in the set mimicking complicated lesion examinations (82% reduction for peak skin dose, p < 0.001; 70% reduction for scattered dose, p < 0.001). DARCA reduces both peak skin dose and scattered dose in comparison to SA. The benefi t of radiation dose reduction could be especially signifi cant in complicated lesion examinations due to large reduction in X-ray exposure time. The use of DARCA could, therefore, be recommended in clinical practice to minimize radiation dose.

Comparison of radiation dose to operator between transradial and transfemoral coronary angiography with optimised radiation protection: a phantom study.

A growing concern in applying radial access in cardiac catheterisation is the increased operator radiation exposure. This study used an anthropomorphic phantom to simulate transradial and transfemoral coronary angiography with optimised radiation protection conditions. Operator radiation exposure was measured with thermoluminescent dosemeters at predefined locations. Compared with the femoral route, the radial route was associated with a dose decrease of 15 % at the operator's chest level with optimised radiation shielding. However, radiation exposure to the operator's hand remained significantly higher when applying radial access even with collective protective equipment used (by a factor of 2). Furthermore, the efficiency of operator radiation protection was found to be dependent on the tube incidence. Awareness should be raised about the significant increase of radiation exposure to operators' hands in transradial coronary angiography. Protection to reduce the dose level to the hands is necessary and should be further improved.

Impact of StentBoost subtract imaging on patient radiation exposure during percutaneous coronary intervention.

The purpose of this study was to assess the impact of StentBoost Subtract (SBS) imaging on patient radiation dose during percutaneous coronary intervention. Data were prospectively collected between February 2010 and November 2012 at a tertiary cardiac catheterization. All patients who had scheduled for coronary stent implantation performed by one expert interventional cardiologist with sufficient experience in SBS imaging and radiation protection, were included. The patients were divided into groups with or without SBS. A multiple linear regression analysis was used to determine the impact of SBS imaging on patient radiation dose. Of 712 patients screened, 414 patients were enrolled in the study (with SBS: n = 177, without SBS: n = 237). Although the DAP, fluoroscopy time and cine frames used in the group with SBS were significantly increased when compared with those used in the group without SBS (P < 0.05), multiple linear regression shows SBS imaging has no significant impact on patient radiation dose (P > 0.05). Multivariate predictors of patient radiation dose were the patients' BMI, B2/C lesions, number of stents placed and bifurcation stenting (P < 0.05). In selected patients, SBS imaging can be performed with comparable patient radiation dose, compared with plain fluoroscopic imaging. This may attribute to the operator's sufficient experience in SBS imaging and radiation protection.

Administration of a loading dose of atorvastatin before percutaneous coronary intervention prevents inflammation and reduces myocardial injury in STEMI patients: a randomized clinical study.

BACKGROUND: Administration of a loading dose of atorvastatin 80 mg/d has been shown to be beneficial in patients with stable coronary artery disease and acute coronary syndromes. However, little is known about the impact and mechanism behind the beneficial effects of loading-dose atorvastatin treatment before percutaneous coronary intervention (PCI), especially for those patients experiencing cardiovascular inflammation in ST-segment elevation myocardial infarction (STEMI). OBJECTIVE: The goal of this randomized clinical study was to investigate whether, before emergency PCI, administration of loading-dose atorvastatin therapy in STEMI patients inhibits inflammation and improves cardiac function during 24 weeks of follow-up. METHODS: A total of 102 STEMI patients were enrolled into 3 groups: group A (n = 32) received 80 mg of atorvastatin before emergency PCI, post-PCI follow-up atorvastatin 40 mg for 4 weeks, and atorvastatin 20 mg for 20 weeks; group B (n = 32) received no pre-PCI loading dose of atorvastatin but did receive atorvastatin 40 mg for 4 weeks and then atorvastatin 20 mg for 20 weeks; and group C (n = 38) received only post-PCI atorvastatin 20 mg for 24 weeks. RESULTS: No differences were found in baseline demographic and angiographic characteristics among the 3 groups. Patients in group A had the lowest plasma levels of high-sensitivity C-reactive protein (hs-CRP), B-type natriuretic peptide (BNP), and matrix metalloproteinase type 9 (MMP-9) (P < 0.05). Patients in group A also showed improvement in heart performance, with significant increases in their left ventricular ejection fraction. To a lesser extent, group B displayed reductions in the plasma levels of hs-CRP, BNP, and MMP-9 at later time points (P < 0.05). Compared with those in group C, patients in group B also exhibited significant improvement in left ventricular ejection fraction (P < 0.05). CONCLUSIONS: Loading-dose atorvastatin therapy before emergency PCI reduced the inflammatory response and myocardial dysfunction in these STEMI patients by lowering hs-CRP, BNP, and MMP-9. Pre-PCI loading-dose atorvastatin treatment may help prevent inflammatory response and improve cardiac function in patients with acute coronary syndromes undergoing emergency PCI. ClinicalTrials.gov identifier: NCT01334671.

Long-term effects of biodegradable versus durable polymer-coated sirolimus-eluting stents on coronary arterial wall morphology assessed by virtual histology intravascular ultrasound.

BACKGROUND: The durable presence of polymer coating on drug-eluting stent (DES) surface may be one of the principal reasons for stent thrombosis. The long-term coronary arterial response to biodegradable polymer-coated sirolimus-eluting stent (BSES) in vivo remained unclear. METHODS: Forty-one patients were enrolled in this study and virtual histology intravascular ultrasound (VH-IVUS) was performed to assess the native artery vascular responses to BSES compared with durable polymer-coated SES (DSES) during long-term follow-up (median: 8 months). The incidence of necrotic core abutting to the lumen was evaluated at follow-up. RESULTS: With similar in-stent late luminal loss (0.15 mm (0.06-0.30 mm) vs. 0.19 mm (0.03-0.30 mm), P = 0.772), the overall incidence of necrotic core abutting to the lumen was significantly less in BSES group than in DSES group (44% vs. 63%, P < 0.05) (proximal 18%, stented site 14% and distal 12% in BSES group, proximal 19%, stented site 28% and distal 16% in DSES group). The DSES-treated segments had a significant higher incidence of necrotic core abutting to the lumen through the stent struts (73% vs. 36%, P < 0.01). In addition, more multiple necrotic core abutting to the lumen was observed in DSES group (overall: 63% vs. 36%, P < 0.05). Furthermore, when the stented segments with necrotic core abutting to the lumen had been taken into account only, DSES-treated lesions tended to contain more multiple necrotic core abutting to the lumen through the stent struts than BSES-treated lesions (74% vs. 33%), although there was no statistically significant difference between them (P = 0.06). CONCLUSIONS: By VH-IVUS analysis at follow-up, a greater frequency of stable lesion morphometry was shown in lesions treated with BSESs compared with lesions treated with DSESs. The major reason was BSES produced less toxicity to the arterial wall and facilitated neointimal healing as a result of polymer coating on DES surface biodegraded as time went by.

Coronary plaque characterization of nonculprit or nontarget lesions assessed by analysis of in vivo intracoronary ultrasound radio-frequency data.

BACKGROUND: Unheralded sudden death and acute myocardial infarction are common manifestations of coronary atherosclerosis. Such events are related to thrombotic occlusion at the site of non-flow limiting atherosclerotic plaques in epicardial coronary arteries. This study aimed to assess plaque characterization of nonculprit lesions in patients with acute coronary syndrome (ACS) compared with those with stable angina pectoris (SAP) determined by analysis of intravascular ultrasound (IVUS) radiofrequency (RF) data. METHODS: In 81 patients, nonculprit vessels with < 50% diameter stenosis and nontarget segment of culprit vessels with < 50% diameter stenosis were studied with IVUS. Tissue maps were reconstructed from RF data using IVUS-Virtual Histology software. RESULTS: Mean lipid core percentage was significantly higher in patients with ACS than in those with SAP ((25.78 +/- 6.30)% vs (9.11 +/- 4.90)%, P < 0.001). In addition, patients with SAP showed more fibrotic vessels ((59.66 +/- 16.87)% vs (49.07 +/- 10.20)%, P < 0.001). There was no significant difference in either mean calcium ((4.37 +/- 2.40)% vs (5.12 +/- 3.00)%, P = 0.225) or fibrolipid ((24.94 +/- 9.40)% vs (25.82 +/- 13.60)%, P = 0.731) percentages in nonculprit vessels, but the mean calcium percentage was significantly higher in nontarget lesions of culprit vessels ((5.51 +/- 3.29)% vs (3.57 +/- 2.10)%, P = 0.003). In addition, there was a positive correlation between lipid core and remodeling index (RI) (r = 0.847, P < 0.001) and a negative correlation between fibrous tissue and RI (r = -0.946, P < 0.001). CONCLUSIONS: In this study, in both nonculprit vessels and nontarget lesion of culprit vessels, plaque characterization of nonculprit lesions determined by spectral analysis of IVUS RF data was significantly different in patients with ACS. The percentage of lipid core was significantly higher in patients with ACS than in those with SAP. Conversely, SAP patients showed more fibrotic content. In vivo plaque composition and morphological changes were related to remodeling of the coronary artery tree.