Carbon dioxide digital subtraction angiography as an option for detection of endoleaks in endovascular abdominal aortic aneurysm repair procedure

ObjectiveThe purpose of this study was to evaluate carbon dioxide digital subtraction angiography (CO2-DSA) as an option for the detection of endoleaks (ELs) in the endovascular abdominal aortic aneurysm repair (EVAR) procedure.MethodsForty patients with abdominal aortic aneurysm who were scheduled to undergo EVAR were enrolled in the study. There were 35 men and five women (mean age, 77.9 years). All patients had both iodinated contrast conventional DSA (C-DSA) and CO2-DSA immediately after EVAR. The sensitivity and specificity were calculated for the ability of CO2-DSA to detect ELs. We also correlated with computed tomography findings 6 months after EVAR.ResultsC-DSA showed that 27 of the 40 patients (68%) had 28 ELs (type I, four; type II, 20; type III, three; type IV, one). CO2-DSA showed that 16 of the 40 patients (40%) had 17 ELs (type I, four; type II, 10; type III, three; type IV, none). For the prediction of direct ELs (type I and type III) with use of C-DSA as the criterion standard, CO2-DSA has a sensitivity of 1.0 and a specificity of 1.0. For the detection of persistent type II ELs (n = 11) with use of computed tomography findings 6 months from EVAR as the criterion standard, CO2-DSA has a sensitivity of 0.87 and a specificity of 0.97. C-DSA has a sensitivity of 0.82 and a specificity of 0.64.ConclusionsCO2-DSA is reliable for the detection of direct ELs and persistent type II ELs in EVAR. CO2-DSA can be an option to detect ELs in the EVAR procedure

Phos-tag-based approach to study protein phosphorylation in the thylakoid membrane

Protein phosphorylation is a fundamental post-translational modification in all organisms. In photoautotrophic organisms, protein phosphorylation is essential for the fine-tuning of photosynthesis. The reversible phosphorylation of the photosystem II (PSII) core and the light-harvesting complex of PSII (LHCII) contribute to the regulation of photosynthetic activities. Besides the phosphorylation of these major proteins, recent phosphoproteomic analyses have revealed that several proteins are phosphorylated in the thylakoid membrane. In this study, we utilized the Phos-tag technology for a comprehensive assessment of protein phosphorylation in the thylakoid membrane of Arabidopsis. Phos-tag SDS-PAGE enables the mobility shift of phosphorylated proteins compared with their non-phosphorylated isoform, thus differentiating phosphorylated proteins from their non-phosphorylated isoforms. We extrapolated this technique to two-dimensional (2D) SDS-PAGE for detecting protein phosphorylation in the thylakoid membrane. Thylakoid proteins were separated in the first dimension by conventional SDS-PAGE and in the second dimension by Phos-tag SDS-PAGE. In addition to the isolation of major phosphorylated photosynthesis-related proteins, 2D Phos-tag SDS-PAGE enabled the detection of several minor phosphorylated proteins in the thylakoid membrane. The analysis of the thylakoid kinase mutants demonstrated that light-dependent protein phosphorylation was mainly restricted to the phosphorylation of the PSII core and LHCII proteins. Furthermore, we assessed the phosphorylation states of the structural domains of the thylakoid membrane, grana core, grana margin, and stroma lamella. Overall, these results demonstrated that Phos-tag SDS-PAGE is a useful biochemical tool for studying in vivo protein phosphorylation in the thylakoid membrane protein

Incisional atrial reentrant tachycardia: experimental study on the conduction property through the isthmus

AbstractBackgroundIncisional atrial reentrant tachycardia is a life-threatening tachyarrhythmia after surgery for congenital heart disease. Slow conduction through an isthmus between anatomical barriers, such as a right atriotomy or the sites for cannulation, has been shown to be a prerequisite for perpetuation of the incisional atrial reentrant tachycardia. However, the conduction property through the isthmus has not been examined in detail.MethodsTo examine the conduction property, 2 tandem incisions were made on the lateral right atrium with various distances (3 to 20 mm) between the incisions in 16 canines. Four weeks after the surgery, the lateral right atrium was mapped epicardially during pacing to examine the conduction property through the isthmus. The conduction property was characterized by approximated curves of the conduction velocity through the isthmus in accordance with the pacing cycle lengths. The atrial tissue at the isthmus was examined microscopically.ResultsThe approximated curves of the conduction velocity were classified into 3 different types. Decremental conduction was observed only in the isthmi between 5 and 15 mm in width. A small amount of surviving myocardium between the scars formed the critical isthmus microscopically (decremental type). In the isthmi wider than 15 mm in width, slow conduction was not seen at any paced cycle length (nondecremental type). In the extremely narrow isthmi less than 5 mm in width, all of the atrial myocardium at the isthmus was replaced by fibrous tissue. Conduction was blocked at the isthmus and the activation detoured around the incisions (block type). There was a statistically significant difference in the approximated curves between the 3 different types of conduction properties (P < .01).ConclusionThe width of the isthmus determines the conduction property through the isthmus that contributes to the development of the incisional atrial reentrant tachycardia. Thus, the incisional atrial reentrant tachycardia may be preventable by leaving a sufficient amount of surviving myocardium between the incisions or by connecting the incisions by an ablative procedure

Biosynthesis, Mode of Action, and Functional Significance of Neurosteroids in the Purkinje Cell

The brain has traditionally been considered to be a target site of peripheral steroid hormones. In addition to this classical concept, we now know that the brain has the capacity to synthesize steroids de novo from cholesterol, the so-called “neurosteroids.” In the middle 1990s, the Purkinje cell, an important cerebellar neuron, was identified as a major site for neurosteroid formation in the brain of mammals and other vertebrates. This discovery has provided the opportunity to understand neuronal neurosteroidogenesis in the brain. In addition, biological actions of neurosteroids are becoming clear by the studies using the Purkinje cell, an excellent cellular model, which is known to play an important role in memory and learning processes. Based on the studies on mammals over the past decade, it is considered that the Purkinje cell actively synthesizes progesterone and estradiol from cholesterol during neonatal life, when cerebellar neuronal circuit formation occurs. Both progesterone and estradiol promote dendritic growth, spinogenesis, and synaptogenesis via each cognate nuclear receptor in the developing Purkinje cell. Such neurosteroid actions mediated by neurotrophic factors may contribute to the formation of cerebellar neuronal circuit during neonatal life. 3α,5α-Tetrahydroprogesterone (allopregnanolone), a progesterone metabolite, is also synthesized in the cerebellum and considered to act as a survival factor of Purkinje cells in the neonate. This review summarizes the current knowledge regarding the biosynthesis, mode of action, and functional significance of neurosteroids in the Purkinje cell during development in terms of synaptic formation of cerebellar neuronal networks

Map-guided surgery for atrial fibrillation

BackgroundAlthough current surgical procedures result in a high success rate for atrial fibrillation, they are not guided by electrophysiologic findings in individual patients and thus might include unnecessary incisions in some patients or be inappropriate for other patients. We sought to determine whether intraoperative mapping is beneficial for the surgical treatment of atrial fibrillation.MethodsA 256-channel 3-dimensional dynamic mapping system with custom-made epicardial patch electrodes was used to examine the atrial activation during atrial fibrillation and to determine the optimal procedure in 37 patients with continuous and 9 patients with intermittent atrial fibrillation intraoperatively.ResultsSurgical intervention for atrial fibrillation was not indicated in 3 patients in whom the atrial electrograms had a low voltage over a broad area. Concurrent, multiple, and repetitive activations arising from the pulmonary veins or left atrial appendage were observed in all patients. A simple left atrial procedure consisting of pulmonary vein isolation and left atrial incisions without any right atrial incisions was performed in 8 patients in whom the right atrial activation was passive, and all (100%) were cured of atrial fibrillation. The radial procedure was performed in the remaining 35 patients, and 31 (89%) of the patients were cured of atrial fibrillation. In this subset of patients, 10 exhibited reentrant or focal activation in the posterior left atrium between the right and left pulmonary veins and required an additional linear ablation on the posterior left atrium. The total amount of postoperative bleeding after the simple left atrial procedure was significantly less than after the radial procedure (378 ± 135 vs 711 ± 364 mL, P = .03). The right and left atrial transport functions were well preserved after both the radial and simple left atrial procedures.ConclusionIntraoperative mapping facilitates determining the optimal procedure for atrial fibrillation in each patient

Toward Understanding the Origin of Turbulence in Molecular Clouds: Small Scale Structures as Units of Dynamical Multi-Phase Interstellar Medium

In order to investigate the origin of the interstellar turbulence, detailed observations in the CO J=1--0 and 3--2 lines have been carried out in an interacting region of a molecular cloud with an HII region. As a result, several 1,000 to 10,000 AU scale cloudlets with small velocity dispersion are detected, whose systemic velocities have a relatively large scatter of a few km/s. It is suggested that the cloud is composed of small-scale dense and cold structures and their overlapping effect makes it appear to be a turbulent entity as a whole. This picture strongly supports the two-phase model of turbulent medium driven by thermal instability proposed previously. On the surface of the present cloud, the turbulence is likely to be driven by thermal instability following ionization shock compression and UV irradiation. Those small scale structures with line width of ~ 0.6 km/s have a relatively high CO line ratio of J=3--2 to 1--0, 1 < R(3-2/1-0) < 2. The large velocity gradient analysis implies that the 0.6 km/s width component cloudlets have an average density of 10^{3-4} cm^{-3}, which is relatively high at cloud edges, but their masses are only < 0.05 M_{sun}.Comment: 12 pages, 9 figures. To be published in the Astrophysical Journa

Contraction Function of the Left Ventricle in Patients with Dilated Cardiomyopathy: Comparison of Delayed Enhanced MR imaging and indine -123- metaiodobenzylguanidine (123I-MIBG) scintigram

Objective: The purpose of this study was to compare delayed enhancement (DE) cardiac magnetic resonance (MR) imaging with the indine-123-metaiodobenzylguanidine(123I-MIBG) scintigram for measurement of left ventricular (LV) contraction function in patients with dilated cardiomyopathy (DCM). Materials and methods: DCM patients (n=29: mean age,51.9years; seven women) were evaluated by both DE cardiac MR imaging and 123I-MIBG scintigram. In all patients biopsy specimen showed disarray of the myocardium that was consistent with DCM. DE cardiac MR images were acquired using a two-dimensional segmented inversion-recovery prepared gradient-echo sequence (TI=250msec) 15minutes after intravenous administration of 0.1 mmol/kg gadolinium.The average CNR per slice (aCNR) for the LV myocardium was calculated.123I-MIBG scintigram was acquired at 15minutes and 3 hours (delayed imaging) after intravenous administration of 123I-MIBG (111MBq). The heart-to-mediastinum radioactivity ratio (H/M ratio) and washout rate (WR) was calculated. We evaluated the relationships between aCNR, WR, delayed H/M ratio, and the contraction function of the LV. Results: In MR imaging, mean aCNR was significantly higher in the low LV ejection fraction (LVEF<25%) group (n=11, 6.6±3.6) than in the high LVEF (?25%) group (n=18, 2.4±2.9). However, with the 123I-MIBG scintigram, delayed H/M and WR were not significantly different between high (delayed H/M ratio ; 1.7±0.3, WR; 37.6±14.5) and low (delayed H/M ratio; 1.7±0.2, WR; 38.2±14.2) LVEF groups. Conclusions: DE MR imaging reflects the contraction function of the LV in patients with DCM, which may be related with myocardial fibrosis. DE MR imaging may be more useful to evaluate the contraction function of LV than 123I-MIBG scintigram

Renal Oncocytoma Associated With Long-Term Hemodialysis

A 50-year old woman was admitted to our hospital for further evaluation of the right renal tumor. She had been on maintenance hemodialysis for 12 years. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a large right renal tumor. There was no central stellate scar. Angiography showed hypervascularity and tumor staining . With the pre-operative diagnosis of renal cell carcinoma, right nephrectomy was performed. The pathological diagnosis was renal oncocytoma