Diagnostic Intravascular Imaging Modalities for Cardiac Allograft Vasculopathy

Cardiac allograft vasculopathy (CAV) is one of the major factors limiting long-term survival after heart transplantation (HTX). Typically, concentric vascular thickening and fibrosis with marked intimal proliferation are found in CAV. Most of HTX patients often remain free from symptoms of typical angina. Therefore, surveillance diagnostic exams are often performed. The gold standard of diagnosing CAV is coronary angiography (CAG). However, CAG can often be a less sensitive modality for the detection of diffuse concentric lesions. Intravascular ultrasound (IVUS) is helpful for direct imaging of vessel walls and provides useful information about coronary intimal thickening; however, it is difficult to evaluate plaque morphology in detail. Optimal coherence tomography (OCT), which delivers high resolution of 10 μm, can provide more details on plaque morphology than conventional imaging modalities. Recently, OCT imaging revealed new insight in CAV such as the development of atherosclerotic lesions and complicated coronary lesions. We review the pathogenesis, clinical features, diagnosis of CAV, with a particular focus on diagnostic intravascular imaging modalities

Induction Therapy in the Current Immunosuppressive Therapy

The current immunosuppressive therapy including calcineurin inhibitors, mycophenolate mofetil, and steroids, has substantially suppress rejections and improved clinical outcomes in heart transplant (HTx) recipients. Nevertheless, the management of drug-related nephrotoxicity, fatal acute cellular rejection (ACR), antibody-mediated rejection and infections remains challenging. Although previous some studies suggested that perioperative induction immunosuppressive therapy may be effective for the suppressing ACR and deterioration of renal function, increased incidence of infection and malignancy was concerned in recipients with induction immunosuppressive therapy. The international society of heart and lung transplantation (ISHLT) guidelines for the care of heart transplant recipients do not recommend routine use of induction immunosuppressive therapy, except for the patients with high risk of acute rejection or renal dysfunction, however, appropriate therapeutic regimen and indication of induction immunosuppressive therapy remains unclear in HTx recipients. We review current evidence of induction immunosuppressive therapy in HTx recipients, and discuss the appropriate therapeutic regimen and indication of induction therapy

Comparison of 2 expression systems using COS7 cells and yeast cells for expression of heart/muscle-type carnitine palmitoyltransferase 1 (CPT1b)

Carnitine palmitoyltransferase 1 (CPT1), catalyzing the transfer of the acyl group from acyl-CoA to carnitine to form acylcarnitine, is located at the outer mitochondrial membrane. Because it is easily inactivated by solubilization, expression systems using living cells are essential for its functional characterization. COS7 cells or yeast cells are often utilized for this purpose; however, the advantages/disadvantages of the use of these cells or the question as to how the CPT1 enzyme expressed by these cells differs are still uncertain. In this study, we characterized the heart/muscle-type isozyme of rat CPT1 (CPT1b) expressed by these 2 cellular expression systems. The mitochondrial fraction prepared from yeast cells expressing CPT1b showed 25% higher CPT1 activity than that obtained from COS7 cells. However, the expression level of CPT1b in the former was 3.8 times lower than that in the latter; and thus, under the present experimental conditions, the specific activity of CPT1b expressed in yeast cells was estimated to be approximately 5 times higher than that expressed in COS7 cells. Possible reasons for this difference are discussed

Ultralong C(sp3)-C(sp3) Single Bonds Shortened and Stabilized by London Dispersion

A carbon-carbon (C-C) single bond longer than 1.7 angstrom shows unique bond flexibility, even though a C-C single bond is typically rigid and robust. We report here that the bond length of flexible C-C single bonds surrounded by bulky alkyl groups in novel hexaphenylethane-type hydrocarbons might be affected by weak noncovalent interactions, such as London dispersion. Thanks to London dispersion, an ultralong and flexible C-C single bond exhibits an obvious bond contraction. X-ray analyses and Raman spectroscopy provided direct information regarding the bond length and strength, whereas density functional theory calculations explained the bond contraction driven by London dispersion. The change in bond length of an extremely elongated flexible C-C bond would be a good probe for quantifying weak interactions that are usually difficult to detect

Di-μ-oxo Dimetal Core of Mn^IV and Ti^IV as a Linker Between Two Chiral Salen Complexes Leading to the Stereoselective Formation of Different <i>M</i>- and <i>P</i>‑Helical Structures

Because of restricted rotational freedom along the metal–metal axis, a di-μ-oxo dimetal core could be an excellent building block to create dinuclear compounds with well-defined stereochemistry, but their stereoselective synthesis remains a challenge. We herein report the formation of di-μ-oxo dimanganese­(IV) complexes with tetradentate salen ligands bearing different degrees of steric bulk, in order to study stereochemical aspects of the dimerization reaction that potentially generates multiple stereoisomers. X-ray crystallography shows that the di-μ-oxo dimanganese­(IV) complex with salen, where salen is (<i>R</i>,<i>R</i>)-<i>N</i>,<i>N</i>′-bis­(3,5-di-<i>tert</i>-butylsalicylidene)-1,2-cyclohexanediamine, adopts a unique structure in which two salen complexes are arranged in an <i>M</i>-helical fashion. According to the solution study using ¹H, ²H NMR, and circular dichroism spectroscopies, the dimerization reaction is highly diastereoselective in the presence of the <i>tert</i>-butyl group at the 3/3′ position as a determinant steric factor. In contrast, the di-μ-oxo dititanium­(IV) complex with the same salen ligand was previously reported to afford an opposite <i>P</i>-helical dimer. The present DFT study clarifies that a less-covalent Ti–O bonding causes a distortion of the di-μ-oxo dititanium­(IV) core structure, generating a completely different framework for interligand interaction. The present study provides a solid basis to understand the stereochemistry for the formation of the di-μ-oxo dimetal core

Improved language function for post-stroke aphasia in the long term following repeated repetitive transcranial magnetic stimulation and intensive speech-language-hearing therapy: a case report

Abstract Background There have been no papers reporting improvement in language function and changes in cerebral blood flow following repeated use of repetitive transcranial magnetic stimulation in combination with intensive speech-language-hearing therapy. This case report concerns the efficacy of repeated use of repetitive transcranial magnetic stimulation and intensive speech-language-hearing therapy for a certain patient suffering from aphasia following stroke, plus the findings of the cerebral blood flow measurements. Case presentation The patient was a 71-year-old right-handed Japanese male who developed fluent aphasia following a left middle cerebral artery stroke. He underwent repetitive transcranial magnetic stimulation and intensive speech-language-hearing therapy five times in total. The repetitive transcranial magnetic stimulation was applied to right inferior frontal gyrus at the frequency of 1 Hz plus 2 hours per day of intensive speech-language-hearing therapy. The patient’s language function was evaluated in the short term and long term. Cerebral blood flow was measured with single photon emission computed tomography scan. As a result, in the short term, the patient’s language function improved especially during the initial hospitalization. In the long term, it improved gradually and stabilized.Cerebral blood flow was increased in the right hemisphere. Conclusions The findings of the study indicate that the repeated use of repetitive transcranial magnetic stimulation and intensive speech-language-hearing therapy may be effective in improving and preserving language function and increasing cerebral blood flow for aphasia following stroke

Coordination Pattern of the Thigh, Pelvic, and Lumbar Movements during the Gait of Patients with Hip Osteoarthritis

There are limited reports on segment movement and their coordination pattern during gait in patients with hip osteoarthritis. To avoid the excessive stress toward the hip and relevant joints, it is important to investigate the coordination pattern between these segment movements, focusing on the time series data. This study aimed to quantify the coordination pattern of lumbar, pelvic, and thigh movements during gait in patients with hip osteoarthritis and in a control group. An inertial measurement unit was used to measure the lumbar, pelvic, and thigh angular velocities during gait of 11 patients with hip osteoarthritis and 11 controls. The vector coding technique was applied, and the coupling angle and the appearance rate of coordination pattern in each direction were calculated and compared with the control group. Compared with the control group, with respect to the lumbar/pelvic segment movements, the patients with hip osteoarthritis spent more rates in anti-phase and lower rates in in-phase lateral tilt movement. With respect to the pelvic/thigh segment movements, the patients with hip osteoarthritis spent more rates within the proximal- and in-phases for lateral tilt movement. Furthermore, patients with osteoarthritis spent lower rates in the distal-phase for anterior/posterior tilt and rotational movement. Patients with hip osteoarthritis could not move their pelvic and thigh segments separately, which indicates the stiffness of the hip joint. The rotational movement and lateral tilt movements, especially, were limited, which is known as Duchenne limp. To maintain the gait ability, it seems important to pay attention to these directional movements

Dose Reduction and Diagnostic Performance of Tin Filter–Based Spectral Shaping CT in Patients with Colorectal Cancer

Routine CT examinations are crucial in colorectal cancer patients (CCPs); however, the high frequency of radiation exposure is a significant concern. This study investigated the radiation dose, image quality, and diagnostic performance of tin filter-based spectral shaping chest–abdominal–pelvic (CAP) CT for CCPs. We reviewed 44 CCPs who underwent single-phase enhanced tin-filtered 100 kV (TF100kV) and standard 120 kV (ST120kV) CAP CT on separate days. Radiation metrics including the volume CT dose index (CTDIvol), dose-length product (DLP), and effective dose (ED) were calculated for both protocols. Two radiologists assessed the presence of the following lesions: lung metastasis, liver metastasis, lymph node metastasis, peritoneal dissemination, and bone metastasis. The area under the receiver operating characteristic curve (AUC) was calculated for the diagnostic performance of each protocol. Radiation metrics of the TF100kV protocol were significantly lower than those of the ST120kV protocol (CDTIvol 1.60 ± 0.31 mGy vs. 14.4 ± 2.50, p p p < 0.0001, respectively). TF100kV protocol achieved comparable diagnostic performance to that of the ST120kV protocol (AUC for lung metastasis: 1.00 vs. 0.94; liver metastasis: 0.88 vs. 0.83, respectively). TF100kV protocol could substantially reduce the radiation dose by 89% compared to that with the ST120kV protocol while maintaining good diagnostic performance in CCPs