A Modified Vancomycin Molecule Confers Potent Inhibitory Efficacy against Resistant Bacteria Mediated by Metallo-ß-Lactamases.

Multidrug-resistant bacterial infections mediated by metallo-ß-lactamases (MßLs) have grown into an emergent health threat, and development of novel antimicrobials is an ideal strategy to combat the infections. Herein, a novel vancomycin derivative Vb was constructed by conjugation of triazolylthioacetamide and vancomycin molecules, characterized by reverse-phase high performance liquid chromatography (HPLC) and confirmed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). The biological assays revealed that Vb effectively inhibited S. aureus and methicillin-resistant S. aureus (MRSA), gradually increased the antimicrobial effect of ß-lactam antibiotics (cefazolin, meropenem and penicillin G) and exhibited a dose-dependent synergistic antibacterial effect against eight resistant strains tested, which was confirmed by the time-kill curves determination. Most importantly, Vb increased the antimicrobial effect of meropenem against the clinical isolates EC08 and EC10 and E. coli producing ImiS and CcrA, resulting in a 4- and 8-fold reduction in MIC values, respectively, at a dose up to 32 µg/mL. This work offers a promising scaffold for the development of MßLs inhibitors, specifically antimicrobials for clinically drug-resistant isolates.

Copper(II) and iron(III) complexes of chiral dehydroabietic acid derived from natural rosin: metal effect on structure and cytotoxicity.

A novel optically pure dinuclear copper(II) complex of a rosin derivative dehydroabietic acid (DHA, HL) was synthesized and fully characterized. The in vitro antitumor activities of the copper(II) complex Cu2(µ2-O)(L)4(DMF)2 (1) were explored and compared with those of a trinuclear iron(III) complex [Fe3(µ3-O)(L)6(CH3OH)2(CH3O)]·H2O (2). 1 was more cytotoxic than 2, and the in vitro cytotoxicity of 1 was comparable to that of cisplatin and oxaliplatin. The metal coordination improved the cytotoxicity of DHA. 1 could arrest cycle in G1 phase and induce apoptosis in MCF-7 cell. 1 increased reactive oxygen species level, GSSG/GSH ratio, and Ca2+ production, and caused the loss of mitochondrial membrane potential (Δψm) in MCF-7 cells. The up-regulated Bax and down-regulated Bcl-2 expression levels, caspase-9/caspase-3 activation, and the release of Cyt c demonstrate that 1 triggered mitochondria-mediated intrinsic apoptosis in MCF-7 cells. Caspase-8/caspase-4 activation and up-regulated Fas expression indicate that death receptor-mediated extrinsic apoptosis was included. Comet assay and up-regulated γ-H2AX and p53 expressions confirmed that 1 caused DNA damage in MCF-7 cells. Moreover, 1 led to enhancement of the biomarker of lipid peroxidation and the indicator of protein carbonylation in MCF-7 cells. All the results suggest that 1 could kill MCF-7 cells by generating oxidative stress, impairing DNA, promoting lipid peroxidation and protein carbonylation, and inducing apoptosis and autophagy. Furthermore, 1 also displayed antimetastatic activities with inhibition of cell invasion and migration, together with antiangiogenesis properties. On the whole, copper complex based on rosin derivatives is worth developing as metal-based antitumor drugs.

Discovery of novel dehydroabietic acid derivatives as DNA/BSA binding and anticancer agents.

To explore the biological properties of rosin derivatives, two dehydroabietic acid derivatives N-(5-dehydroabietyl-1,3,4-thiadiazole)-yl-pyridine-2-carboxamide (DTPC) and di-N-(5-dehydroabietyl-1,3,4-thiadiazole)-yl-pyridine-2,6-carboxamide (DDTPC) with 1,3,4-thiadiazole, pyridine and amide moieties were designed and synthesized according to superposition principle of activity group. They interact with calf thymus DNA (CT DNA) via intercalation based on the results of circular dichroism (CD) and fluorescence spectroscopy, DNA denaturation and viscosity studies. Fluorescence and CD spectral experiments indicate that they might be transported and stored by protein like bovine serum albumin (BSA). MTT assay was further carried out to examine their cytotoxicity, they both showed selective cytotoxicity and DTPC exhibited better cytotoxicity. The antiproliferative effect of DTPC toward A431 cell line was stronger than that of clinically used cisplatin and oxaliplatin. In addition, the cytotoxicity of DTPC and DDTPC was closely related with their DNA binding ability.

A Whole-Tumor Histogram Analysis of Apparent Diffusion Coefficient Maps for Differentiating Thymic Carcinoma from Lymphoma.

Objective: To assess the performance of a whole-tumor histogram analysis of apparent diffusion coefficient (ADC) maps in differentiating thymic carcinoma from lymphoma, and compare it with that of a commonly used hot-spot region-of-interest (ROI)-based ADC measurement. Materials and Methods: Diffusion weighted imaging data of 15 patients with thymic carcinoma and 13 patients with lymphoma were retrospectively collected and processed with a mono-exponential model. ADC measurements were performed by using a histogram-based and hot-spot-ROI-based approach. In the histogram-based approach, the following parameters were generated: mean ADC (ADCmean), median ADC (ADCmedian), 10th and 90th percentile of ADC (ADC10 and ADC90), kurtosis, and skewness. The difference in ADCs between thymic carcinoma and lymphoma was compared using a t test. Receiver operating characteristic analyses were conducted to determine and compare the differentiating performance of ADCs. Results: Lymphoma demonstrated significantly lower ADCmean, ADCmedian, ADC10, ADC90, and hot-spot-ROI-based mean ADC than those found in thymic carcinoma (all p values < 0.05). There were no differences found in the kurtosis (p = 0.412) and skewness (p = 0.273). The ADC10 demonstrated optimal differentiating performance (cut-off value, 0.403 × 10-3 mm2/s; area under the receiver operating characteristic curve [AUC], 0.977; sensitivity, 92.3%; specificity, 93.3%), followed by the ADCmean, ADCmedian, ADC90, and hot-spot-ROI-based mean ADC. The AUC of ADC10 was significantly higher than that of the hot spot ROI based ADC (0.977 vs. 0.797, p = 0.036). Conclusion: Compared with the commonly used hot spot ROI based ADC measurement, a histogram analysis of ADC maps can improve the differentiating performance between thymic carcinoma and lymphoma.

Histogram analysis of apparent diffusion coefficient maps for assessing thymic epithelial tumours: correlation with world health organization classification and clinical staging.

OBJECTIVE: To investigate the value of apparent diffusion coefficients (ADCs) histogram analysis for assessing World Health Organization (WHO) pathological classification and Masaoka clinical stages of thymic epithelial tumours. METHODS: 37 patients with histologically confirmed thymic epithelial tumours were enrolled. ADC measurements were performed using hot-spot ROI (ADCHS-ROI) and histogram-based approach. ADC histogram parameters included mean ADC (ADCmean), median ADC (ADCmedian), 10 and 90 percentile of ADC (ADC10 and ADC90), kurtosis and skewness. One-way ANOVA, independent-sample t-test, and receiver operating characteristic were used for statistical analyses. RESULTS: There were significant differences in ADCmean, ADCmedian, ADC10, ADC90 and ADCHS-ROI among low-risk thymoma (type A, AB, B1; n = 14), high-risk thymoma (type B2, B3; n = 9) and thymic carcinoma (type C, n = 14) groups (all p-values <0.05), while no significant difference in skewness (p = 0.181) and kurtosis (p = 0.088). ADC10 showed best differentiating ability (cut-off value, ≤0.689 × 10-3 mm2 s-1; AUC, 0.957; sensitivity, 95.65%; specificity, 92.86%) for discriminating low-risk thymoma from high-risk thymoma and thymic carcinoma. Advanced Masaoka stages (Stage III and IV; n = 24) tumours showed significant lower ADC parameters and higher kurtosis than early Masaoka stage (Stage I and II; n = 13) tumours (all p-values <0.05), while no significant difference on skewness (p = 0.063). ADC10 showed best differentiating ability (cut-off value, ≤0.689 × 10-3 mm2 s-1; AUC, 0.913; sensitivity, 91.30%; specificity, 85.71%) for discriminating advanced and early Masaoka stage epithelial tumours. CONCLUSION: ADC histogram analysis may assist in assessing the WHO pathological classification and Masaoka clinical stages of thymic epithelial tumours. Advances in knowledge: 1. ADC histogram analysis could help to assess WHO pathological classification of thymic epithelial tumours. 2. ADC histogram analysis could help to evaluate Masaoka clinical stages of thymic epithelial tumours. 3. ADC10 might be a promising imaging biomarker for assessing and characterizing thymic epithelial tumours.

Retrospective Evaluation of Safety, Efficacy and Risk Factors for Pneumothorax in Simultaneous Localizations of Multiple Pulmonary Nodules Using Hook Wire System.

PURPOSE: To evaluate the safety and efficacy of the hook wire system in the simultaneous localizations for multiple pulmonary nodules (PNs) before video-assisted thoracoscopic surgery (VATS), and to clarify the risk factors for pneumothorax associated with the localization procedure. METHODS: Between January 2010 and February 2016, 67 patients (147 nodules, Group A) underwent simultaneous localizations for multiple PNs using a hook wire system. The demographic, localization procedure-related information and the occurrence rate of pneumothorax were assessed and compared with a control group (349 patients, 349 nodules, Group B). Multivariate logistic regression analyses were used to determine the risk factors for pneumothorax during the localization procedure. RESULTS: All the 147 nodules were successfully localized. Four (2.7%) hook wires dislodged before VATS procedure, but all these four lesions were successfully resected according to the insertion route of hook wire. Pathological diagnoses were acquired for all 147 nodules. Compared with Group B, Group A demonstrated significantly longer procedure time (p < 0.001) and higher occurrence rate of pneumothorax (p = 0.019). Multivariate logistic regression analysis indicated that position change during localization procedure (OR 2.675, p = 0.021) and the nodules located in the ipsilateral lung (OR 9.404, p < 0.001) were independent risk factors for pneumothorax. CONCLUSION: Simultaneous localizations for multiple PNs using a hook wire system before VATS procedure were safe and effective. Compared with localization for single PN, simultaneous localizations for multiple PNs were prone to the occurrence of pneumothorax. Position change during localization procedure and the nodules located in the ipsilateral lung were independent risk factors for pneumothorax.

Identification of three novel B-cell epitopes of VMH protein from Vibrio mimicus by screening a phage display peptide library.

Vibrio mimicus is the causative agent of ascites disease in fish. The heat-labile hemolytic toxin designated VMH is an immunoprotective antigen of V. mimicus. However, its epitopes have not been well characterized. Here, a commercially available phage displayed 12-mer peptide library was used to screen epitopes of VMH protein using polyclonal rabbit anti-rVMH protein antibodies, and then five positive phage clones were identified by sandwich and competitive ELISA. Sequences analysis showed that the motif of DPTLL displayed on phage clone 15 and the consensus motif of SLDDDST displayed on the clone 4/11 corresponded to the residues 134-138 and 238-244 of VMH protein, respectively, and the synthetic motif peptides could also be recognized by anti-rVMH-HD antibody in peptide-ELISA. Thus, both motifs DPTLL and SLDDDST were identified as minimal linear B-cell epitopes of VMH protein. Although no similarity was found between VMH protein and the consensus motif of ADGLVPR displayed on the clone 2/6, the synthetic peptide ADGLVPR could absorb anti-rVMH-HD antibody and inhibit the antibody binding to rVMH protein in enhanced chemoluminescence Western blotting, whereas irrelevant control peptide did not affect the antibody binding with rVMH. These results revealed that the peptide ADGLVPR was a mimotope of VMH protein. Taken together, three novel B-cell epitopes of VMH protein were identified, which provide a foundation for developing epitope-based vaccine against V. mimicus infection in fish.

[Value of dual-source computed tomography angiography of coronary artery for preoperative evaluation of old patients scheduled for noncardiac surgery].

OBJECTIVE: To assess the role of computed tomography angiography (CTA) using dual-source computed tomography in the preoperative evaluation of old patients scheduled for noncardiac surgery. METHODS: A retrospective review of the clinical data of patients who underwent CTA in our hospital between May 2011 and May 2013 was performed, and totally 111 old patients with risk factors of coronary artery diseases scheduled for noncardiac surgery were found to coronary CTA for preoperative evaluation. Prospectively electrocardiograph-triggered sequence scan protocol with dual-source computed tomography was performed. The imaging quality, coronary artery stenosis, the treatment before operation, and perioperative complications were assessed. RESULTS: For 1 779 coronary artery segments in 111 patients, the number of evaluable segments was 1 676 (97.4%). The mean effective dose of CTA was (2.7 ± 0.9) mSv. Among them, 71 patients with coronary artery stenosis <50% underwent surgery without cardiac complication and 17 patients with coronary artery stenosis ≥ 70% underwent conventional coronary angiography and coronary angioplasty or bypass surgery. The sensitivity and specificity of CTA in detecting ≥ 50% stenosis were 95% and 96%, and the sensitivity and specificity of CTA in detecting ≥ 70% stenosis were 97% and 98%. For 19 patients with coronary artery stenosis between 50% and 70%, the levels of myocardial enzyme were transiently higher for two patients, and no other cardiac complication occurred. CONCLUSION: Coronary artery CTA is reliable in artery stenosis evaluation and can be used as cardiac risk stratification for old patients scheduled for noncardiac surgery.

128-slice Dual-source Computed Tomography Coronary Angiography in Patients with Atrial Fibrillation: Image Quality and Radiation Dose of Prospectively Electrocardiogram-triggered Sequential Scan Compared with Retrospectively Electrocardiogram-gated Spiral Scan.

Objective To evaluate the image quality (IQ) and radiation dose of 128-slice dual-source computed tomography (DSCT) coronary angiography using prospectively electrocardiogram (ECG)-triggered sequential scan mode compared with ECG-gated spiral scan mode in a population with atrial fibrillation. Methods Thirty-two patients with suspected coronary artery disease and permanent atrial fibrillation referred for a second-generation 128-slice DSCT coronary angiography were included in the prospective study. Of them, 17 patients (sequential group) were randomly selected to use a prospectively ECG-triggered sequential scan, while the other 15 patients (spiral group) used a retrospectively ECG-gated spiral scan. The IQ was assessed by two readers independently, using a four-point grading scale from excel-lent (grade 1) to non-assessable (grade 4), based on the American Heart Association 15-segment model. IQ of each segment and effective dose of each patient were compared between the two groups. Results The mean heart rate (HR) of the sequential group was 96±27 beats per minute (bpm) with a variation range of 73±25 bpm, while the mean HR of the spiral group was 86±22 bpm with a variationrange of 65±24 bpm. Both of the mean HR (t=1.91, P=0.243) and HR variation range (t=0.950, P=0.350) had no significant difference between the two groups. In per-segment analysis, IQ of the sequential group vs. spiral group was rated as excellent (grade 1) in 190/244 (78%) vs. 177/217 (82%) by reader1 and 197/245 (80%) vs. 174/214 (81%) by reader2, as non-assessable (grade 4) in 4/244 (2%) vs. 2/217 (1%) by reader1 and 6/245 (2%) vs. 4/214 (2%) by reader2. Overall averaged IQ per-patient in the sequential and spiral group showed equally good (1.27±0.19 vs. 1.25±0.22, Z=-0.834, P=0.404). The effective radiation dose of the sequential group reduced significantly compared with the spiral group (4.88±1.77 mSv vs. 10.20±3.64 mSv; t=-5.372, P=0.000). Conclusion Compared with retrospectively ECG-gated spiral scan, prospectively ECG-triggered sequential DSCT coronary angiography provides similarly diagnostically valuable images in patients with atrial fibrillation and significantly reduces radiation dose.

In vivo and in vitro imaging tracing of dual-labeled bone mesenchymal stem cells transplanted into myocardium of F344 rats.

OBJECTIVE: To investigate the feasibility of in vitro and in vivo magnetic resonance imaging (MRI) and fluorescence imaging tracking of transplanted bone mesenchymal stem cells (BMSCs) dual-labeled with ultrasmall superparamagnetic iron oxide (USPIO) and red fluorescence protein (RFP). METHODS: BMSCs were incubated with culture medium containing USPIO for 24 hours. The Prussian-blue staining, transmission electron microscopy and trypan-blue staining were used to study the efficacy and safety of labeling. F344 rat model of acute myocardial infarction was established by ligating the left anterior descending coronary artery. The dual-labeled BMSCs were injected into the margin of the infraction myocardium. Then MRI and fluorescence imaging were performed to trace the cells both in vitro and in vivo. Postmortal study was carried out to observe the distribution of transplanted cells in myocardium. RESULTS: The percentage of dual-labeled BMSCs reached 99% after co-incubating with USPIO for 24 hours. USPIO particles were mainly located in lysosomes. As demonstrated by trypan-blue staining, there was no significant deference in viability between labeled and unlabeled groups (P>0.05). All dual-labeled transplanted BMSCs showed a significant decreasing signal on MRI, and the signal intensity changes had no significant difference over 4 weeks (P=0.66). In vitro cell tracing with fluorescence imaging of isolated heart from F344 rats was successful,while in vivo cell tracing with fluorescence imaging failed. Prussian blue staining showed that USPIO distributed near the infarcted myocardium, corresponding with the fluorescence imaging. CONCLUSION: MRI can be used to trace the dual-labeled BMSCs transplanted into F344 rat hearts in vivo, while fluorescence imaging and pathological fluorescence imaging can trace the transplanted cells in vitro.

Assessment of coronary stents by 64-slice computed tomography: in-stent lumen visibility and patency.

OBJECTIVE: To assess lumen visibility of coronary stents by 64-slice computed tomography (CT) coronary angiography, and determine the value of 64-slice CT in non-invasive detecting of in-stent restenosis after coronary artery stent implantation. METHODS: Totally, 60 patients (54 males, aged 57.0+/-12.7 years) and 105 stents were investigated by 64-slice CT at a mean interval of 20.0+/-16.6 months after coronary stents implantation. Axial multi-planar reconstruction images of the stents and curved-planar reconstruction images through the median of the stents were reconstructed for evaluating stent image quality on a 5-point scale (1=excellent, 5=non-assessable), and stent lumen diameter was detected. Conventional coronary angiography was performed in 18 patients, and 32 stents were evaluated. RESULTS: Image quality was good to excellent on average (score 1.71+/-0.76). Stent image quality score was correlated to heart rate (r=0.281, P<0.01) and stent diameter (r=-0.480, P<0.001). All the stents were assessable in lumen visibility with an average visible lumen diameter percentage of 60.7%+/-13.6%. Visible lumen diameter percentage was correlated to heart rate (r=-0.193, P<0.05), stent diameter (r=0.403, P<0.001), and stent image quality score (r=-0.500, P<0.001). Visible lumen diameter percentage also varied depending on the stent type. In comparison with the conventional coronary angiography, 4 of 6 in-stent stenoses were correctly detected. The sensitivity and specificity for the detection of in-stent stenosis were 66.7% and 84.6%, respectively. CONCLUSIONS: Using a 64-slice CT, the stent lumen is partly visible in most of the stents. And 64-slice CT may be useful in the assessment of stent patency.

[Diagnostic value of dual-source CT coronary angiography on the detection of coronary artery disease with myocardial perfusion defect].

OBJECTIVE: To determine the accuracy of dual-source CT (DSCT) coronary angiography (CAG) for the diagnosis of coronary artery disease (CAD) that induces perfusion defects at myocardial perfusion imaging (MPI) with single photon emission computed tomography (SPECT), by using SPECT and conventional CAG as the reference standard. METHODS: Thirty-five patients with suspected or known CAD underwent both DSCT coronary angiography and MPI (using exercise or adenosine stress-rest protocol) with technetium-99m sestamibi SPECT. All the patients were beta-blockers-naïve before DSCT scan. The DSCT CAG studies were classified as having no stenosis, non-obstructive (< 50% luminal narrowing) stenosis, or obstructive (> or = 50% luminal narrowing) stenosis. MPI examinations were classified as showing normal or abnormal (reversible and/or fixed defects). A comparative regional analysis of coronary stenosis on DSCT versus myocardial perfusion on SPECT was made. In a subset of 20 patients, CAG was performed as a reference standard for CT angiography. RESULTS: On the basis of the DSCT data, 98.4% of coronary segments were assessable. Twenty-seven branches were classified as having no stenosis, among which 85% had normal MPI. Nine branches showed non-obstructive stenosis and 69 branches showed at least one obstructive lesion. Only 50 (64%) branches with an abnormal DSCT had abnormal MPI; even in branches with obstructive stenosis on DSCT, 23 (33%) still had a normal MPI. By receiver operating characteristic curve analysis, at the optimal cutoff value of 58% stenosis, the sensitivity and specificity of DSCT to detect myocardial perfusion defect as defined by SPECT were 85% and 65%. In the subgroup compared with CAG, the sensitivity and specificity of DSCT to identify obstructive stenosis were 93% and 96%. CONCLUSIONS: DSCT and SPECT provide mutually complementary information on CAD. CT angiography can help rule out functionally relevant CAD, but has poor capability in predicting ischemia. DSCT provides high-quality diagnostic image without heartbeat controlling and has a high accuracy in detecting obstructive stenosis.

[Evaluation of cardiac structure and function by cardiac magnetic resonance imaging in healthy volunteers].

OBJECTIVE: To evaluate the role of cardiac magnetic resonance (CMR) sequence in assessing the cardiac structure and function. METHODS: A total of 36 healthy volunteers were examined with fast imaging employing steady-state acquisition cine MR sequence. All the MR images were processed on Report Card software to test the cardiac dimensions and function. The relationships between the CMR results and the ultrasonic cardiography (UCG) results were analyzed. RESULTS: CMR analysis showed that interventricular septum thickness, left ventricle posterior wall thickness, end diastolic dimension of left ventricle, and end systolic dimension of left ventricle were (9.2 +/- 2.1), (8.0 +/- 2.1), (48.6 +/- 5.5), and (30.3 +/- 5.3) mm, respectively. Major dimension of right ventricle, minor dimension of right ventricle, index of major, dimension of right ventricle and index of minor dimension of right ventricle were (69.2 +/- 9.7), (30.6 +/- 6.6) mm, and (39.4 +/- 5.5), (18.1 +/- 3.4) min/m2, respectively. The left ventricle indicators above measured by CMR correlated with those by UCG (r = 0.843, 0.784, 0.686, 0.730, all P < 0.01). CMR analysis showed that left ventricular end diastolic volume, right ventricular end diastolic volume, left ventricular end systolic volume, and right ventricular end systolic volume were (93.6 +/- 17.2), (108.6 +/- 28.2), (39.5 +/- 13.0), and (45.6 +/- 15.1) ml, respectively. The left ventricular ejection fraction and right ventricular ejection fraction were (58.5 +/- 8.19)% and (58.2 +/- 7.4)% , respectively. Left ventricular ejection fraction measured by CMR was correlated with that (64.1 +/- 6.8)% by UCG (r = 0.75, P < 0.01). CONCLUSIONS: CMR sequence with standard location is well applicable for accurate measurement of left and right ventricle dimensions and function, especially for right ventricle. CMR can be used to diagnose the heart disease and monitor the efficacy.

[Assessment of global left ventricular function by 64-slice spiral CT in patients with old myocardial infarction].

OBJECTIVE: To investigate the clinical value of 64-slice spiral CT (64SCT) in assessing global left ventricular function in patients with old myocardial infarction (OMI), with magnetic resonance imaging (MRI) as the reference standard. METHODS: A total of 28 patients (23 men and 5 women) with OMI underwent contrast-enhanced 64SCT with retrospective electrocardiographic-gating, MRI, and transthoracic echocardiography (Echo). The data sets of 64SCT and MRI were reconstructed at both end-diastole and end-systole to measure left ventricular end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejective fraction (EF), and myocardial mass at end-diastole (MM). The data acquired with 64SCT and Echo were compared with the results obtained on MRI as the standard of reference respectively. RESULTS: The parameters of global left ventricular function obtained with 64SCT were significantly correlated with the MRI data (r = 0.788-0.976, P < 0.001). EDV, ESV, SV, EF, and MM were slightly overestimated by 64SCT compared with MRI; however, there was no significant difference among the measurements. 64SCT was in good agreement with MRI. For the EDV, ESV, SV, and EF, the limits of agreement with Echo were significantly larger than with 64SCT compared with MRI (P < 0.05). The sensitivity, specificity, and accuracy of 64SCT to identify EF value less than 50% were 84.6%, 100% and 92.9%, respectively, whereas those of Echo were 61.5%, 66.7% and 64.3%, respectively. The accuracy of 64SCT was significantly higher than that of Echo (P < 0.01). There was a significantly larger overestimation of EDV, ESV, and SV with Echo than with 64SCT compared with MRI (P < 0.05), whereas EF was not significantly different. CONCLUSIONS: A strong correlation between 64SCT and MRI is found for all parameters. 64SCT agrees well with MRI, and allows more reliable and accurate evaluation of global left ventricular function in patients with OMI than Echo compared with MRI.

Coronary angiography with dual source computed tomography: initial experience.

OBJECTIVE: To explore the scan technique and image quality of coronary angiography with dual source computed tomography (CT) without oral metoprolol preparation. METHODS: Plain and enhanced dual source CT coronary angiography without oral metoprolol preparation was prospectively performed in 600 patients. Calcium scoring with plain scan images as well as multi-planar reconstruction (MPR), maximum intensity projection (MIP), and volume rendering technique (VRT) reconstruction with enhanced scan images were performed in all cases. The scan technique and post-reconstruction experience was summarized. The image quality was classified as 1 to 4 points, and coronary segments classified according to the American Heart Association standards were evaluated. RESULTS: The average calcium score of the 600 cases was 213.6 +/- 298.7 (0-3,216.5). The average heart rate of the enhanced scan was 82.1 +/- 16.2 (47-139) bpm. The post-reconstruction methods with which coronary segments could be shown as best as possible consisted of single phase reconstruction method, two or more phases supplemented method, and electrocardiogram editing method. Altogether 8,457 coronary segments were evaluated, among which 97.2% were evaluated as point 1, 1.7% point 2, 0.5% point 3, and 0.6% point 4. The coronary segments in 261 cases were completely normal, while 360 segments were diagnosed with < 50% stenosis and 625 segments with > or = 50% stenosis. CONCLUSIONS: Excellent coronary artery image can be obtained with dual source CT in patients with any heart rate without oral metoprolol preparation. Heart rate is not a major source of the artifact, coronary segments can be well shown with single or multiple-phase reconstruction method.

Cadmium(II) and copper(II) complexes with imidazole-containing tripodal polyamine ligands: pH and anion effects on carbon dioxide fixation and assembling.

A new Cd(II) complex [Cd3(L)3(mu3-CO3)](ClO4)4.2CH3CN (1) with two-dimensional (2D) network structure was obtained by reaction of an imidazole-containing tripodal polyamine ligand N1-(2-aminoethyl)-N1-(2-imidazolethyl)-ethane-1,2-diamine (L) with Cd(ClO4)2.6H2O at pH 9.0 in air. The carbonate anions (CO3(2-)) are from the hydration of the atmospheric carbon dioxide, which is the same as in the previously reported Cu(II) complex [Cu3(L)3(mu3-CO3)](ClO4)4.3CH3CN (2). However, the coordination mode of CO3(2-) in 1 is mu3-eta2:eta2:eta2 while the one in 2 is mu3-eta1:eta1:eta1. One-dimensional (1D) chain Cd(II) and Cu(II) complexes [Cd(L)Cl]ClO4.H2O (3) and [Cu(L)(H2O)](ClO4)2 (4) without CO3(2-) were prepared by a similar method as that for 1 and 2 except for the different reaction pH, namely, 3 and 4 were obtained at pH 7 while 1 and 2 were obtained at pH 9. In addition, when Cu(NO3)2 was used to react with L at pH 9, a unique 1D double-stranded helical chain complex [Cu(L)Cl]NO3.1.25H2O (5) was obtained. The results revealed that the reaction pH and the counteranion have great impact on the carbon dioxide absorption and hydration as well as on the assembling and structure of the complexes. The magnetic property of complex 2 was investigated in the temperature range of 1.8-300 K, and weak ferromagnetic coupling among the mu3-eta1:eta1:eta1-CO3(2-) bridged Cu(II) atoms was observed.

Dinuclear zinc(II) complex with novel tripodal polyamine ligand: synthesis, structure and kinetic study of carboxy ester hydrolysis.

An imidazole-containing tripodal polyamine ligand N(1)-(2-aminoethyl)-N(1)-(2-imidazol-1-ylethyl)-ethane-1,2-diamine (L) was prepared and its dinuclear zinc(II) complex [Zn(L)(H(2)O)](2)(ClO(4))(4).4H(2)O (1) was obtained and examined as a catalyst for the hydrolysis of 4-nitrophenyl acetate (NA). X-ray crystal structure analysis of the complex revealed that the complex features a dinuclear cation unit with a Zn...Zn distance of 8.34A and both Zn(II) centers adopt distorted trigonal-bipyramid geometry. The solution complexation investigation performed at 25 degrees C by means of potentiometric titration revealed that the mononuclear species [ZnL](2+) is predominating in the pH rage of 7.0-9.7 in the solution and the pK(a1) for the Zn-bound water is 8.50+/-0.01. Complex 1 promoted hydrolysis of NA showed a second-order rate constant of 0.046+/-0.004 M(-1)s(-1) at pH 9.0 in 10% (v/v) CH(3)CN aqueous solution at 25 degrees C. The pH-rate profile for the second-order rate constant of NA hydrolysis with complex 1 gave a sigmoidal curve. And the results show that in the hydrolysis process the two Zn(II) centers of the dinuclear deprotonated species do not cooperate with each other and the Zn-bound hydroxide servers as reactive nucleophile toward the ester.

[Comparison of coronary artery bypass graft imaging between 64-slice and 16-slice spiral CT].

OBJECTIVE: To compare the coronary artery bypass graft (CABG) imaging between 16-slice spiral CT and 64-slice spiral CT. METHODS: Totally 27 patients with CABG received multi-slice spiral CT imaging and the results were retrospectively analyzed. Among them, 8 patients received 16-slice spiral CT scanning, 19 patients received 64-slice spiral CT scanning. RESULTS: The evaluability rates of 64-slice spiral CT in evaluating the proximal anastomosis, bypass graft, distal anastomosis, and distal blood vessel were 100%, 100%, 90.2%, and 93.9%, respectively, while those of 16-slice spiral CT were 92.3%, 95.2%, 90.0%, and 90.0%, respectively. The patency rates of the above four aspects of 64-slice spiral CT were 66.7%, 70.0%, 71.7%, and 70.0%, respectively, while those of 16-slice spiral CT were 83.3%, 85.0%, 83.3%, and 88.9% . CONCLUSIONS: 64-slice spiral CT is superior to 16-slice spiral CT in CABG imaging. It can be used as a non-invasive tool for the post-operative follow-up of CABG.

[Assessment of coronary stent lumen visibility and patency by 64-slice spiral CT angiography].

OBJECTIVE: To evaluate the clinical value of assessment of coronary stent patency by 64-slice spiral CT coronary angiography. METHODS: Totally 29 patients (59 stents) were investigated using a retrospective ECG-gated enhanced scan by 64-slice spiral CT at a mean interval of (28.4 +/- 21.2) months after coronary stent implantation. Axial multi-planar reconstruction (MPR) of the stents and curved-planar reconstruction (CPR) through the stents were evaluated for image quality on a 5-point scale (1 = excellent, 5 = uninterpretable) and lumen diameter. Stent lumen diameter was compared with the vessel diameter proximal of the stents to assess the in-stent lumen visibility. Conventional coronary angiography was performed in 5 patients, and 9 stents were evaluated. RESULTS: The image quality was good to excellent on average (scores: 1.94 +/- 0.84), depending on heart rate, breath movement, and stent location. Stent lumen was visible, on average a percentage off (76.1 +/- 11.1)% of the lumen diameter. All the 9 stents were correctly detected as being patent, which was confirmed by conventional coronary angiography. CONCLUSION: 64-slice spiral CT is a useful tool to assess the coronary stent patency.

[Comparison of coronary angiography between 64-slice and 16-slice spiral CT].

OBJECTIVE: To compare the image quality and visibility of arteries of 64-slice spiral coronary CT angiography (CTA) with those of 16-slice spiral coronary CTA, and to evaluate the diagnostic accuracy of 64-slice spiral CT for the assessment of coronary artery stenosis. METHODS: Totally 100 patients (Group A) with suspected coronary artery diseases (CAD) were examined by 64-slice spiral CT, 48 of whom also underwent conventional coronary angiography (CAG). Another 100 patients (Group B) with suspected CAD were studied by 16-slice spiral CT. Patients with a heart rate above 70 bpm received oral beta-blockers before the scan. Data were retrospectively analyzed and reviewed by two observers. Image quality was assessed by using a 3-point grading scale from excellent (1) to non-assessable (3) and the rate of displayed coronary branches was calculated. The left main artery (LM), left anterior descending artery (LAD), circumflex artery (CX), and right coronary artery (RCA) were screened for the presence of over 50% stenosis. RESULTS: The mean heart rates of two groups showed no significant difference [(61 +/- 8) bpm vs. (61 +/- 7) bpm, P > 0.05]. The mean scan time of Group A was significantly shorter than that of Group B [(11.9 +/- 0.9) s vs. (22.2 +/- 1.1) s, P < 0.01]. In the evaluation of image quality, better results were obtained in Group A than in Group B (1.20 +/- 0.47 vs. 1.37 +/- 0. 63, P < 0.05). The visibility of proximal arteries was similar between two groups, while the visibility of some distal arteries and small branches was found higher in Group A than in Group B (LAD distal 92% vs. 48%, CX distal 98% vs. 89%, the first obtuse marginal (OMI) 93% vs. 84%, cone branch (CB) 86% vs. 71%, P < 0.05). Compared with CAG, the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 64-slice spiral coronary CTA to identify over 50% stenosis were 94.9% (56/59), 93.2% (124/133), 86.2% (56/65), and 97.6% (124/127), respectively. CONCLUSIONS: With higher temporal and spatial resolution, 64-slice spiral CT provides improved image quality and visibility of small branches as compared with 16-slice spiral CT. 64-slice spiral coronary CTA allows reliable non-invasive diagnosis of obvious coronary artery stenosis.