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Background: Traditional radiography angles do not adequately reveal the shape and position of the right ventricular pacing electrode. background: Traditional radiography angles do not adequately reveal the shape and position of the right ventricular pacing electrode. The best radiography angle was explored by the help of cardiac computed tomography (CT) . Objective: This study aimed to explore better radiography angles with the help of cardiac computed tomography (CT). objective: We want to find a solution of radiography angles that can fully demonstrate the shape and length of the cardiac pacing electrode to better serve the clinical. Methods: We analyzed the cardiac CT images of consecutive outpatients from 2018 to 2019. The right anterior oblique (RAO) 30° and the left anterior oblique (LAO) 40° were found to sufficiently display the shape and position of the right ventricular pacing electrode. method: We analyzed the cardiac CT images of consecutive outpatients obtained from 2018-2019. The right anterior oblique (RAO) 30° and the left anterior oblique (LAO) 40° were found to sufficiently display the shape and position of the right ventricular pacing electrode. Results: A total of 214 consecutive outpatients were enrolled, whose average age was 55.0 ± 13.0 years, and 151 were male (70.6%). Through analyzing the cardiac CT images, the α angle (33.7° ± 6.1) and the γ angle (38.8° ± 8.0) were determined. Furthermore, we verified these angles in 48 patients after pacemaker implantation. The results showed that the ratio of the length of right ventricular electrode using the RAO α angle (≈30°) to the posterior-anterior position (PA position) was 1.099 ± 0.157 VS 1.053 ± 0.182 (the ratio using the traditional RAO 45°) (P < 0.001). We observed that the relationship between the right ventricular active electrode and the ventricular septum was better identified using the LAO γ angle (≈40°) than the traditional 60° angle. Conclusion: With the help of cardiac CT, we found that RAO 30° could better show the shape and length of the right ventricular pacing electrode, and LAO 40° could better show the positional relationship between the pacing electrode and the ventricular septum. other: none

To assess the variation in left atrial (LA) and biventricular strain and its prognostic value in the course of suspected myocarditis, this retrospective study included 55 patients with clinically suspected myocarditis who underwent cardiac magnetic resonance (CMR) examinations at baseline and follow-up periods. Cine images were used for feature tracking analysis. Paired Student’s t test, McNemar’s test, and Cox proportional hazard regression were used for statistical analysis. The LA total emptying fraction was the only functional index that showed a statistically significant improvement. The initial LA peak’s late negative strain rate (SRa) was the only parameter with a significant predictive power of major adverse cardiac events under univariable (hazard ratio [HR] 2.396, 95% confidence interval [CI] 1.044–5.498, p = 0.039) and multivariable Cox survival analysis when adjusted by LA strain parameters (HR 5.072, 95% CI 1.478–17.404, p = 0.010), LA strain and functional parameters (HR 7.197, 95% CI 1.679–30.846, p = 0.008), and LA and biventricular strain and functional parameters (HR 10.389, 95% CI 2.250–47.977, p = 0.003). Thus, our findings indicate that CMR strain is useful for monitoring LA and ventricular function in suspected myocarditis, that LA function may recover preceding ventricular function changes, and that LA strain may serve as an incremental tool to predict adverse outcomes.

Background: Primary cardiac angiosarcoma is a rare malignancy with high predilection to involve surrounding structures such as pulmonary metastases. We analysed the chest computed tomography (CT) imaging features of patients diagnosed with primary cardiac angiosarcoma with pulmonary metastases in this study. Methods: This study retrospectively reviewed 12 patients with confirmed primary cardiac angiosarcoma, out of which eight (all men) with pulmonary metastasis were included in the analysis. The patients’ age ranged from 17 to 74 (mean: 48) years. CT was performed in all patients with unenhanced, contrast-enhanced, and both scans were done in 1, 3 and 4 patients, respectively. Results: Nodular lesions were observed in 7 patients with multiple solid nodules observed in 6 out of 7 patients. A solitary solid nodule was found in the remaining patient in the upper lobe and apical segment of the right lung with a diameter of 11.7 mm. All solid nodules were distributed along with bronchovascular bundles in the lungs, and their maximum diameter ranged from 2.3 to 19.9 mm. Nodules larger than 10 mm in diameter were heterogeneously enhanced on contrast-enhanced CT images (5/8 patients), whereas those smaller than 10 mm were homogeneously enhanced (3/8 patients). Other imaging features, namely the tree-in-bud pattern, emphysema, pleural effusion, and mediastinal lymph node enlargement, were observed in 4, 3, 3, and 2 patients, respectively. Conclusion: CT enhancement features of pulmonary metastasis in patients with primary cardiac angiosarcoma depend on the size of pulmonary nodules, with larger ones being heterogeneous and smaller ones homogeneous. Other signs are less noticed.

BACKGROUND Late gadolinium enhancement (LGE) is absent in many patients with suspected myocarditis and preserved left ventricular ejection fraction (LV-EF), which poses difficulties in diagnosis and risk stratification. PURPOSE To investigate the diagnostic and prognostic value of ventricular myocardial strain in patients with suspected myocarditis, preserved LV-EF, and negative Lake Louis Criteria (LLC) by comparing the findings in LGE negative and LGE positive patients. STUDY TYPE Retrospective. POPULATION A total of 108 patients with clinically suspected myocarditis who did not satisfy LLC were divided into LGE negative (N = 65) and LGE positive (N = 43) groups. A control group consisted of 50 healthy volunteers. FIELD STRENGTH/SEQUENCE Steady-state free precession cine and phase-sensitive inversion recovery segmented gradient echo LGE sequences at 3.0 T. ASSESSMENT Myocardial strain of the ventricles was evaluated by feature tracking, major adverse cardiovascular events (MACE) were assessed during follow-up since the date of magnetic resonance examination. STATISTICAL TESTS Independent-samples t test, Mann-Whitney U test, receiver operating characteristic curve analysis, and Cox proportional hazard regression were performed. A P-value

Diffuse myocardial interstitial fibrosis (DMIF) is a key factor for heart failure (HF) in diabetic cardiomyopathy. MRI T1-mapping technique can quantitatively evaluate DMIF.To evaluate of early DMIF in a type 1 diabetes mellitus (T1DM) mouse model through 7.0 T MRI T1 mapping.Prospective.A total of 50 8-week-old C57Bl/6J male mice were divided into control (n = 20) and T1DM (n = 30) groups.A 7.0 T small animal MRI; gradient echo Look-Locker inversion recovery T1-mapping sequence; cine MRI. Scans were acquired in control and T1DM mice every 4 weeks until 24 weeks.End-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF), left ventricle (LV) mass, fractional shortening (FS), and E/A ratio. They were evaluated through echocardiography and cine MRI. The extracellular volume fraction (ECV) was calculated. Sirius Red staining was performed and calculated collagen volume fraction (CVF).Differences in ECV and CVF between two groups were analyzed using one-way analysis of variance. The correlation between ECV and CVF was assessed using Pearson's correlations.Compared with the control group, a progressive decrease in FS, EF, and E/A ratio was observed in the T1DM group. Both ECV and CVF values gradually increased during diabetes progression. A significant increase in ECV and CVF values was observed at 12 weeks (ECV: 32.5% ± 1.6% vs. 28.1% ± 1.8%; CVF: 6.9% ± 1.8% vs. 3.3% ± 1.1%). ECV showed a strong correlation with CVF (r = 0.856).ECV is an accurate and feasible imaging marker that can be used to quantitatively assess DMIF changes over time in T1DM mice. ECV has potential to accurately detect DMIF in the early stage and may be a useful imaging tool to assess the need for early intervention in T1DM mice.1 TECHNICAL EFFICACY: Stage 3.

Cardiac magnetic resonance (CMR) offers superior advantages in cardiac imaging due to supplying a greater field of view, excellent soft-tissue imaging, and multiplanar imaging capabilities. CMR imaging can evaluate the characteristics of cardiac tumors by visualizing the relationship between the tumor and surrounding tissues, and plays a vital role in assisting the formulation of the surgical plan, the assessment of tumor progression, and the monitoring of postoperative tumor recurrence and metastasis. In this review, we present the clinical manifestations and imaging features of different cardiac tumors. The superior performance of CMR in preoperative diagnosis, surgical treatment, and postoperative follow-up of patients with heart tumors are also highlighted.

Type 2 diabetes mellitus (T2DM) is associated with a high prevalence of diastolic dysfunction and congestive heart failure. A potential contributing factor is the accelerated accumulation of diffuse myocardial fibrosis and stiffness. Novel cardiac magnetic resonance (CMR) imaging techniques can identify both myocardial fibrosis and contractility quantitatively. This study aimed to investigate the dynamic characteristics of the myocardial strain and altered extracellular volume (ECV) fraction as determined by 7.0 T CMR in T2DM mice. C57Bl/6J mice were randomly divided into T2DM (fed a high-fat diet) and control (fed a normal diet) groups. They were scanned on 7.0 T MRI every 4 weeks until the end of week 24. The CMR protocol included multi-slice cine imaging to assess left ventricle strain and strain rate, and pre- and post-contrast T1 mapping images to quantify ECV. The ECV in the T2DM mice was significantly higher (p < 0.05) than that in the control group since week 12 with significantly impaired myocardial strain (p < 0.05). A significant linear correlation was established between myocardial strain and ECV (p < 0.001) and left ventricular-ejection fraction and ECV (p = 0.003). The results suggested that CMR feature tracking-derived myocardial strain analysis can assess functional abnormalities that may be associated with ECM alterations in diabetic cardiomyopathy, contributing to the study of diabetic therapy effects.

Background Diffuse myocardial interstitial fibrosis (DMIF) is a key factor for heart failure (HF) in diabetic cardiomyopathy. This study examined the accuracy of the qualitative and quantitative evaluation of early DMIF in a type 1 diabetes mellitus (T1DM) mouse model through 7.0 T cardiac magnetic resonance imaging-based T1 mapping.Methods Eight-week-old C57Bl/6J male mice were randomly divided into control (n = 20) and T1DM (n = 30, induced by a low dose streptozotocin dose of 60 mg/kg) groups. The progression of DMIF was examined every 4 weeks until 24 weeks after successful establishment of the model. Cardiac functional and morphological parameters were evaluated through echocardiography by using a high-resolution ultrasound cardiovascular system. A 7.0 T CMR scan was performed using the pre- and post-contrast GRE Look–Locker inversion recovery T1 mapping sequence. The extracellular volume fraction (ECV) was calculated from CMR and hematocrit data. Sirius Red staining was simultaneously performed in each group to detect DMIF and calculate the collagen volume fraction (CVF). Differences in ECV and CVF values between two groups were analyzed using one-way analysis of variance. The correlation between ECV and CVF values was assessed using the Pearson test.Results Six mice were included every 4 weeks in the control and T1DM groups for statistical analysis. Compared with the control group, a progressive decrease in FS, EF, and E/A ratio was observed in the T1DM group. In the T1DM group, both ECV and CVF values were gradually increased during diabetes progression. A marked increase in ECV and CVF values was observed at 12 weeks in the T1DM group than in the control group (ECV: 32.5% ± 1.6% vs 28.1% ± 1.8%, P = 0.002; CVF: 6.9% ± 1.8% vs 3.3% ± 1.1%, P < 0.01). ECV values showed a strong correlation with CVF in the T1DM group (r = 0.856, P < 0.001).Conclusion ECV is a reliable and feasible imaging marker that can be used to quantitatively assess dynamic DMIF changes in T1DM mice. In addition, ECV could accurately detect DMIF in the early stage and thus can be used as an imaging tool for early intervention in T1DM mice in the future.

This study aims to explore computed tomography (CT) and magnetic resonance imaging (MRI) features of patients diagnosed with primary cardiac angiosarcoma. The study involved the analysis of 12 patients diagnosed with primary cardiac angiosarcoma who underwent non-contrast (8/12) or contrast-enhanced CT (10/12) or MRI (4/12). Imaging appearances, including the tumor location and adjacent infiltration, were analyzed. All 12 lesions were located in the right atrium with a broad base. Adjacent invasion including the tricuspid valve and right ventricle (2/12), inferior or superior vena cava (2/12), pericardium (10/12), and right coronary artery (7/12) was common. On unenhanced CT scans, tumors in two patients were homogeneous in density, whereas the others were inhomogeneous. Ten patients showed heterogeneous enhancement. The enhancement pattern showed no direct correlation with the differentiation degree of the tumor. Four lesions manifested as heterogeneous intensity, with hyperintense hemorrhage foci on both T1- and T2-weighted MRI. Three showed rim enhancement and one showed patchy enhancement. Primary cardiac angiosarcoma often involves the right side of the heart with infiltration of peripheral structures. CT features include typical inhomogeneous density on unenhanced scans and heterogeneous centripetal enhancement on enhanced scans. A cauliflower-like appearance on both T1- and T2-weighted MRI is common. The characteristic enhancement pattern of MRI remains to be determined.

The purpose of this study is to evaluate the hemodynamic characteristics of the true lumen (TL) and the false lumen (FL) in 16 patients with aortic dissection (AD) using 4D flow magnetic resonance imaging (MRI) and thoracic and abdominal computed tomography (CT) angiography. The quantitative parameters that were measured in the TL and FL included velocity and flow. The mean area and regurgitant fraction of the TL were significantly lesser at all four levels (p

The purpose of this study was to compare different semi-automated late gadolinium enhancement (LGE) quantification techniques using gadobutrol and gadopentetate dimeglumine contrast agents with regard to the diagnosis of fibrotic myocardium in patients with hypertrophic cardiomyopathy (HCM). Thirty patients with HCM underwent two cardiac MRI protocols with use of gadobutrol and gadopentetate dimeglumine. Contrast-to-noise ratio (CNR) between LGE area and remote myocardium (CNRremote), between LGE area and left ventricular blood pool (CNRpool), and signal-to-noise ratio (SNR) in LGE were compared. The presence and quantity of LGE were determined by visual assessment. With signal threshold versus reference mean (STRM) based thresholds of 2 SD, 5 SD, and 6 SD above the mean signal intensity (SI) of reference myocardium, the full-width at half-maximum (FWHM) technique was used. The volume and segments of the LGE area were compared between the two types of contrast agents. LGE was present in 26 of 30 (86.6%) patients in both protocols. The CNRremote of fibrotic myocardium in gadobutrol and gadopentetate dimeglumine agents was 26.82 ± 14.24 and 21.46 ± 10.59, respectively (P

The aim of this systematic review is to analyse current literature related to the clinical value of three-dimensional (3D) printed models in renal disease. A literature search of PubMed and Scopus databases was performed to identify studies reporting the clinical application and usefulness of 3D printed models in renal disease. Fifteen studies were found to meet the selection criteria and were included in the analysis. Eight of them provided quantitative assessments with five studies focusing on dimensional accuracy of 3D printed models in replicating renal anatomy and tumour, and on measuring tumour volume between 3D printed models and original source images and surgical specimens, with mean difference less than 10%. The other three studies reported that the use of 3D printed models significantly enhanced medical students and specialists' ability to identify anatomical structures when compared to two-dimensional (2D) images alone; and significantly shortened intraoperative ultrasound duration compared to without use of 3D printed models. Seven studies provided qualitative assessments of the usefulness of 3D printed kidney models with findings showing that 3D printed models improved patient's understanding of renal anatomy and pathology; improved medical trainees' understanding of renal malignant tumours when compared to viewing medical images alone; and assisted surgical planning and simulation of renal surgical procedures with significant reductions of intraoperative complications. The cost and time associated with 3D printed kidney model production was reported in 10 studies, with costs ranging from USD$100 to USD$1,000, and duration of 3D printing production up to 31 h. The entire process of 3D printing could take up to a few days. This review shows that 3D printed kidney models are accurate in delineating renal anatomical structures and renal tumours with high accuracy. Patient-specific 3D printed models serve as a useful tool in preoperative planning and simulation of surgical procedures for treatment of renal tumours. Further studies with inclusion of more cases and with a focus on reducing the cost and 3D model production time deserve to be investigated.

Right heart pathology receives less attention from clinicians than left-sided heart disease, and knowledge of the importance of right heart, in particular right ventricle in disease development lags behind that of the left ventricle. In recent years, increasing evidence shows that right heart disease has significant impact on morbidity and mortality, thus highlighting the importance of recognizing right heart disease in clinical practice. Although ultrasound and computed tomography are the most commonly used diagnostic image techniques in the diagnosis of right heart disease, chest radiography still remains the first line technique in many applications. Despite non-specific findings in most of the situations, chest X-ray provides useful information for further diagnostic imaging tests of assessing right heart disease. This chapter provides an overview of applications of chest X-ray in the diagnosis of various right heart diseases.

The B3LYP/6-311++G** study of the mechanism of the cycloaddition of singlet 2,2-dimethyl-1,2-digermavinylidene (Me2Ge=Ge:) to ethylene was performed. [2+2] Cycloaddition of the reactants first produced four-membered cyclic germylene, then the interaction of unoccupied 4p orbital of the Ge atom with the π orbital of another ethylene molecule yielded intermediate with the π → p donor-acceptor bond. Isomerization of this intermediate via low-laying transition state resulted in spirocyclic compound with the sp3 hybridized Ge spiroatom.

The H 2 Si Si: and its derivatives(X 2 Si Si:, X = H, Me, F, Cl, Br, Ph, Ar……) is a new species. Its cycloaddition reactions is a new area for the study of silylene chemistry. The mechanism of the cycloaddition reaction between singlet Me 2 Si Si: and formaldehyde has been investigated with the CCSD(T)//MP2/6-31G ∗ method in article. From the potential energy profile, it could be predict that the reaction has one dominant reaction pathway. The reaction rule presented is that the two reactants firstly form a four-membered Si-heterocyclic ring silylene through the [2+2] cycloaddition reaction. Because of the 3p unoccupied orbital of Si: atom in the four-membered Si-heterocyclic ring silylene and the π orbital of formaldehyde forming a π → p donor–acceptor bond, the four-membered Si-heterocyclic ring silylene further combines with formaldehyde to form an intermediate. Because the Si: atom in intermediate happens sp 3 hybridization after transition state, then, intermediate isomerizes to a spiro-Si-heterocyclic ring compound via a transition state. The research result indicates the laws of cycloaddition reaction between Me 2 Si Si: and formaldehyde, and laid the theory foundation of the cycloaddition reaction between H 2 Si Si: and its derivatives(X 2 Si Si:, X = H, Me, F, Cl, Br, Ph, Ar……) and asymmetric π-bonded compounds, which are significant for the synthesis of small-ring and spiro-Si-heterocyclic ring compounds. The study extends research area and enriched the research content of silylene chemistry.

The mechanism of the cycloaddition reaction between singlet state silylene germylidene (H2Si = Ge:) and ethene has been investigated with the CCSD(T)//MP2/6-31G* method; from the potential energy profile, we predict that the reaction has one dominant reaction pathway. This dominant pathway has the two reactants firstly forming a Si-heterocyclic four-membered ring germylene (INT1) through a [2 + 2] cycloaddition reaction. Due to the sp3 hybridisation of the Ge: atom in INT1, the latter further combines with ethene to form a bis-heterocyclic product containing Si and Ge (P2).

The H2Ge=Ge: and its derivatives (X2Ge=Ge:, X = H, Me, F, Cl, Br, Ph, Ar……) is a new species. Its cycloaddition reactions is a new area for the study of germylene chemistry. The mechanism of the cycloaddition reaction between singlet Me2Ge=Ge: and acetone has been investigated with the B3LYP/6-31G* method in this article. From the potential energy profile, it can be predicted that the reaction has only one dominant reaction pathway. The reaction rule presented is that the two reactants firstly form a four-membered Ge-heterocyclic ring germylene through the [2 + 2] cycloaddition reaction. Because of the 4p unoccupied orbital of Ge: atom in the four-membered Ge-heterocyclic ring germylene and the π orbital of acetone forming a π → p donor–acceptor bond, the four-membered Ge-heterocyclic ring germylene further combines with acetone to form an intermediate. Because the Ge: atom in the intermediate produces sp3 hybridization after a transition state, then the intermediate isomerizes to a spiro-Ge-heterocyclic ring compound via a transition state. The research result indicated the laws of cycloaddition reaction between Me2Ge=Ge: and acetone, and laid the theory foundation of the cycloaddition reaction between H2Ge=Ge: and its derivatives (X2Ge=Ge:, X = H, Me, F, Cl, Br, Ph, Ar……) and asymmetric π-bonded compounds, which is significant for the synthesis of small-ring and spiro-heterocyclic ring compounds involving Ge. The study extends the research area and enriches the research content of germylene chemistry.

The mechanism of the cycloaddition reaction between singlet H 2 Ge Ge: and formaldehyde has been investigated with the CCSD(T)//MP2/6-31G * method. From the potential energy profile, it could be predicted that the reaction has one dominant reaction pathway. The reaction rule presented is that the [2 + 2] cycloaddition reaction between two reactants firstly generates a four-membered Ge-heterocyclic ring germylene. Because the 4p unoccupied orbital of Ge: atom in the four-membered Ge-heterocyclic ring germylene and the π orbital of formaldehyde form a π → p donor–acceptor bond, the four-membered Ge-heterocyclic ring germylene further combines with formaldehyde to form an intermediate. Because the Ge: atom in intermediate happens sp 3 hybridization after transition state, then, intermediate isomerizes to a spiro-Ge-heterocyclic ring compound via a transition state. The research result indicates the laws of cycloaddition reaction between H 2 Ge Ge: and its derivatives(X 2 Ge Ge:, X = F, Cl, CH 3 , Ph, Ar…) and the asymmetric π-bonded compounds, which is significant for the synthesis of small-ring and spiro-Ge-heterocyclic compounds. The study extends research area and enriches the research content of germylene chemistry.

The H2Ge=Ge:, as well as and its derivatives (X2Ge=Ge:, X=H, Me, F, Cl, Br, Ph, Ar, …) is a kind of new species. Its cycloaddition reactions is a new area for the study of germylene chemistry. The mechanism of the cycloaddition reaction between singlet Me2Ge=Ge: and acetaldehyde was investigated with the B3LYP/6‐31G* method in this work. From the potential energy profile, it could be predicted that the reaction has one dominant reaction pathway. The reaction rule is that the two reactants firstly form a four‐membered Ge‐heterocyclic ring germylene through the [2+2] cycloaddition reaction. Because of the 4p unoccupied orbital of Ge: atom in the four‐membered Ge‐heterocyclic ring germylene and the π orbital of acetaldehyde forming a π→p donor‐acceptor bond, the four‐membered Ge‐heterocyclic ring germylene further combines with acetaldehyde to form an intermediate. Because the Ge atom in intermediate happens sp3 hybridization after transition state, then, intermediate isomerizes to a spiro‐Ge‐heterocyclic ri...

The mechanism of the cycloaddition reaction between singlet state dichlorosilylene germylidene () and acetone has been investigated with B3LYP/6- and B3LYP/6- method, from the potential energy profile, we predict that the reaction has one dominant reaction pathway. The presented rule of the reaction is that the two reactants firstly form a Si-heterocyclic four-membered ring germylene through the [2+2] cycloaddition reaction. Because of the 4p unoccupied orbital of Ge atom in the Si-heterocyclic four-membered ring germylene and the orbital of acetone forming a donor-acceptor bond, the Si-heterocyclic four-membered ring germylene further combines with acetone to form an intermediate. Because the Ge atom in the intermediate hybridizes to an hybrid orbital after the transition state, then, the intermediate isomerizes to spiro-heterocyclic ring compound involving Si and Ge (P4) via a transition state.

The mechanism of the cycloaddition reaction between singlet dichlorosilylenesilylene (Cl2Si=Si:)→Cl2Si=Si: and aldehyde has been investigated with the CCSD(T)//MP2/6-31G* method. From the potential energy profile, it could be predicted that the reaction has one dominant reaction pathway. The reaction rules presented is that the two reactants firstly form a four-membered ring silylene through the [2+2] cycloaddition reaction. Because of the 3p unoccupied orbital of Si: atom in the four-membered ring silylene and the π orbital of aldehyde forming a π → p donor–acceptor bond, the four-membered ring silylene further combines with aldehyde to form an intermediate. Because the Si: atom in the intermediate happens sp 3 hybridization after transition state, then the intermediate isomerizes to a spiro-heterocyclic ring compound involving Si via a transition state.

The mechanism of the cycloaddition reaction between singlet dichlorosilylene germylidene (Cl2SiGe:) and formaldehyde has been investigated with the CCSD(T)//MP2/6-31G* method. From the potential energy profile, it could be predicted that the reaction has one dominant reaction pathway. The reaction rule presented is that the two reactants first form a four-membered Si-heterocyclic ring germylene through the [2 + 2] cycloaddition reaction. Because of the 4p unoccupied orbital of Ge atom in the four-membered Si-heterocyclic ring germylene and the π orbital of formaldehyde forming a πp donor–acceptor bond, the four-membered Si-heterocyclic ring germylene further combines with formaldehyde to form an intermediate. Because the Ge atom in intermediate undergoes sp3 hybridization after transition state, then, the intermediate isomerizes to a spiro-heterocyclic ring compound involving Si and Ge via a transition state. © 2012 Wiley Periodicals, Inc.

Objective Current diagnostic assessment tools remain suboptimal in demonstrating complex morphology of congenital heart disease (CHD). This limitation has posed several challenges in preoperative planning, communication in medical practice, and medical education. This study aims to investigate the dimensional accuracy and the clinical value of 3D printed model of CHD in the above three areas. Methods Using cardiac computed tomography angiography (CCTA) data, a patient-specific 3D model of a 20-month-old boy with double outlet right ventricle was printed in Tango Plus material. Pearson correlation coefficient was used to evaluate correlation of the quantitative measurements taken at analogous anatomical locations between the CCTA images pre- and post-3D printing. Qualitative analysis was conducted by distributing surveys to six health professionals (two radiologists, two cardiologists and two cardiac surgeons) and three medical academics to assess the clinical value of the 3D printed model in these three areas. Results Excellent correlation (r = 0.99) was noted in the measurements between CCTA and 3D printed model, with a mean difference of 0.23 mm. Four out of six health professionals found the model to be useful in facilitating preoperative planning, while all of them thought that the model would be invaluable in enhancing patient-doctor communication. All three medical academics found the model to be helpful in teaching, and thought that the students will be able to learn the pathology quicker with better understanding. Conclusion The complex cardiac anatomy can be accurately replicated in flexible material using 3D printing technology. 3D printed heart models could serve as an excellent tool in facilitating preoperative planning, communication in medical practice, and medical education, although further studies with inclusion of more clinical cases are needed.

Isoliquiritigenin (2',4',4-trihydroxychalcone), a chalcone found in licorice root and other plants, has shown potent antitumor, antioxidant, and phytoestrogenic activity in vitro. In preparation for in vivo studies, the metabolism of isoliquiritigenin by human liver microsomes was investigated, and seven phase 1 metabolites were identified. In addition to aromatic hydroxylation that occurred on the A or B ring to form 2',4,4',5'-tetrahydroxychalcone or butein, respectively, reduction of the carbon-carbon double bond of an alpha,beta-unsaturated ketone and cyclization occurred to form 2',4,4'-trihydroxydihydrochalcone and (Z/E)-6,4'-dihydroxyaurone. All metabolites were characterized and identified by using liquid chromatography-tandem mass spectrometry with comparison to authenticated compounds. Finally, monoclonal antibody inhibitors of specific human cytochrome P450 (P450) enzymes and recombinant human P450 enzymes were used to identify the enzymes responsible for the formation of the major mono-oxygenated metabolites, and P450 2C19 was found to be a significant enzyme in the formation of butein from isoliquiritigenin, which also has anticancer activity. Cytochromes P450, reactive oxygen species, and peroxidases can all contribute to the formation of (Z/E)-6,4'-dihydroxyaurone in human liver microsomes.

Objective To investigate the clinical value of renal perfusion imaging in patients with aortic dissection (AD) using 320-row computed tomography (CT), and to determine the relationship between renal CT perfusion imaging and various factors of aortic dissection. Methods Forty-three patients with AD who underwent 320-row CT renal perfusion before operation were prospectively enrolled in this study. Diagnosis of AD was confirmed by transthoracic echocardiography. Blood flow (BF) of bilateral renal perfusion was measured and analyzed. CT perfusion imaging signs of AD in relation to the type of AD, number of entry tears and the false lumen thrombus were observed and compared. Results The BF values of patients with type A AD were significantly lower than those of patients with type B AD (P = 0.004). No significant difference was found in the BF between different numbers of intimal tears (P = 0.288), but BF values were significantly higher in cases with a false lumen without thrombus and renal arteries arising from the true lumen than in those with thrombus (P = 0.036). The BF values measured between the true lumen, false lumen and overriding groups were different (P = 0.02), with the true lumen group having the highest. Also, the difference in BF values between true lumen and false lumen groups was statistically significant (P = 0.016), while no statistical significance was found in the other two groups (P > 0.05). The larger the size of intimal entry tears, the greater the BF values (P = 0.044). Conclusions This study shows a direct correlation between renal CT perfusion changes and AD, with the size, number of intimal tears, different types of AD, different renal artery origins and false lumen thrombosis, significantly affecting the perfusion values.

Purpose To evaluate the diagnostic performance of flow-sensitive dephasing (FSD)-prepared steady-state free precession (SSFP) magnetic resonance angiography (MRA) at 3 T for imaging infragenual arteries relative to contrast-enhanced MRA (CE-MRA) and digital subtraction angiography (DSA). Materials and Methods A series of 16 consecutive patients with peripheral arterial disease (PAD) underwent a combined peripheral MRA protocol consisting of FSD-MRA for the calves and large field-of-view CE-MRA. DSA was performed on all patients within 1 week of the MR angiographies. Image quality and degree of stenosis was assessed by two readers with rich experience. Inter-observer agreement was determined using kappa statistics. Receiver operating characteristic (ROC) curve analysis determined the diagnostic value of FSD-MRA, CE-MRA, and CE-MRA combined with FSD-MRA (CE+FSD MRA) in predicting vascular stenosis. Results At the calf station, no significantly difference of subjective image quality scores was found between FSD-MRA and CE-MRA. Inter-reader agreement was excellent for both FSD-MRA and CE-MRA. Both of FSD-MRA and CE-MRA carry a stenosis overestimation risk relative to DSA standard. With DSA as the reference standard, ROC curve analysis showed that the area under the curve was largest for CE+FSD MRA. The greatest sensitivity and specificity were obtained when a cut-off stenosis score of 2 was used. Conclusion In patients with severe PAD,3 T FSD-MRA provides good-quality diagnostic images without a contrast agent and is a good supplement for CE-MRA. CE+FSD MRA can improve the accuracy of vascular stenosis diagnosis.

International audience; The roots ofAngelica sinensis(Oliv.) Diels (Dang Gui; Apiaceae) have a long history in traditional Chinese medicine as a remedy for women’s disorders and are often called “lady’s ginseng”. Currently, extracts ofA. sinensisare commonly included in numerous dietary supplements used for women’s health and as antiaging products. In the present study, we examined the potential chemopreventive activity ofA. sinensisextracts by measuring the relative ability to induce the detoxification enzyme, NAD(P)H:quinone oxidoreductase 1 (NQO1). The lipophilic partitions showed strong NQO1 induction with concentrations to double the enzyme activity (CD) of 5.5 ± 0.7 (petroleum ether) and 3.9 ± 0.5 μg/mL (chloroform). Fractionation led to the isolation of phenolic esters and alkylphthalides, especiallyZ-ligustilide, the main lipophilic compound, which showed strong NQO1 inducing properties (CD = 6.9 ± 1.9 μM). Transcription of many detoxifying enzymes is regulated through the antioxidant response element (ARE) and its transcription factor Nrf2, which is repressed under basal conditions by Keap1. However, exposure to electrophilic inducers that alkylate Keap1 results in higher concentrations of free Nrf2 and ARE activation. The ARE reporter activity was therefore analyzed in HepG2-ARE-C8 cells after incubation with lipophilic extracts ofA. sinensisor ligustilide for 24 h. Under these conditions, both the extract and the ligustilide increased ARE-luciferase reporter activity in a dose-dependent manner. Incubation of ligustilide with GSH and subsequent LC-MS-MS analysis revealed that ligustilide as well as oxidized ligustilide species covalently modified GSH. In addition, using MALDI-TOF mass spectrometry and LC-MS-MS, it was demonstrated that the lipophilic extracts, ligustilide, and monooxygenated ligustilide alkylated important cysteine residues in human Keap1 protein, thus activating Nrf2 and transcription of ARE regulated genes. These observations suggest thatA. sinensisdietary supplements standardized to ligustilide have potential as chemopreventive agents through induction of detoxification enzymes.

Retinoid X receptors (RXRs) function as ligand-activated transcription factors and are obligatory components of a large number of nuclear receptor heterodimers. RXRs help regulate diverse physiological responses including the cancer prevention responses of cell proliferation, inflammation, cell differentiation, and apoptosis. Since RXRs represent important targets for cancer chemoprevention, an ultrafiltration mass spectrometry-based assay was developed to facilitate the discovery of potential chemoprevention agents that bind to human RXRalpha. Natural and synthetic ligands for RXRalpha including 9-cis-retinoic acid, docosahexaenoic acid, and LG100268 could be detected and identified in DMSO (dimethyl sulfoxide) or even complex matrixes such as extracts of marine bacteria. Specific binding of ligands to RXRalpha was demonstrated through competitive binding using ultrafiltration LC-MS/MS (liquid chromatography-tandem mass spectrometry), and ligands could be ranked in order of affinity for RXRalpha. Therefore, ultrafiltration LC-MS/MS is suitable for the screening of complex mixtures such as natural product extracts for the discovery of new ligands to RXRalpha.