Abdominal imaging at 4 T MR system: a preliminary result

In this study, the potential for abdominal MR images at 4 T using a tailored coil was demonstrated using healthy volunteers. These images were compared with those obtained in the same subject at 1.5 T to discuss whether 4 T would be superior to 1.5 T in abdominal imaging. MR images at 4 T were characterized by high contrast and signal-to-noise ratios, more than 2.95 times higher than those at 1.5 T. In conclusion, abdominal MR imaging at 4 T was feasible. Furthermore, abdominal MR imaging at 4 T was superior to that at 1.5 T in qualitative and quantitative analyses.     

Centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo sequence: improvement of the image quality of oxygen-enhanced MRI

PURPOSE: The purpose of the study presented here was to determine the improvement in image quality of oxygen-enhanced magnetic resonance (MR) subtraction imaging obtained with a centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo (c-IR-HASTE) sequence compared with that obtained with a conventional sequentially reordered inversion recovery single-shot HASTE (s-IR-HASTE) sequence for pulmonary imaging. MATERIALS AND METHODS: Oxygen-enhanced MR imaging using a 1.5 T whole body scanner was performed on 12 healthy, non-smoking volunteers. Oxygen-enhanced MR images were obtained with the coronal two-dimensional (2D) c-IR-HASTE sequence and 2D s-IR-HASTE sequence combined with respiratory triggering. For a 256x256 matrix, 132 phase-encoding steps were acquired including four steps for phase correction. Inter-echo spacing for each sequence was 4.0 ms. The effective echo time (TE) for c-IR-HASTE was 4.0 ms, and 16 ms for s-IR-HASTE. The inversion time (TI) was 900 ms. To determine the improvement in oxygen-enhanced MR subtraction imaging by c-IR-HASTE, CNRs of subtraction image, overall image quality, and image degradation of the c-IR-HASTE and s-IR-HASTE techniques were statistically compared. RESULTS: CNR, overall image quality, and image degradation of c-IR-HASTE images showed significant improvement compared to those s-IR-HASTE images (P<0.05). CONCLUSION: Centrically reordered inversion recovery half-Fourier single-shot turbo spin-echo (c-IR-HASTE) sequence enhanced the signal from the lung and improved the image quality of oxygen-enhanced MR subtraction imaging.     

Role of glucocorticoid receptor in the inhibitory effect of medroxyprogesterone acetate on the estrogen-induced endothelial nitric oxide synthase phosphorylation in human umbilical vein endothelial cells

We aimed to clarify which steroid receptor is involved in the inhibitory effect of medroxyprogesterone acetate (MPA) on estrogen-induced endothelial nitric oxide synthase (eNOS) phosphorylation in human umbilical vein endothelial cells (HUVEC). The progesterone/glucocorticoid receptor (GR) antagonist RU-486 and introduction of GR siRNA caused attenuation of the inhibitory effect of MPA on the estrogen-induced eNOS phosphorylation and eNOS activity in HUVEC.     

Intranasal IL-12 produces discreet pulmonary and systemic effects on allergic inflammation and airway reactivity

IL-12 modulates T cell responses between helper T cells Th2 and Th1; however, the therapeutic potential of IL-12 for allergic diseases either directly or as an adjuvant in allergen therapy has been controversial. The role of intranasal IL-12 as an adjuvant in modulating the grass pollen allergen (GAL) therapy-induced systemic immune response and lung-specific inflammation and airway reactivity was examined in this study using a mouse model of established allergic asthma. The effects of intranasal or nebulized IL-12 with or without intranasal anti-IFN-gamma antibody were examined in groups of control and allergen-sensitized or -challenged mice. T cell cytokine patterns, antibody response profiles, pulmonary inflammation and airway reactivity were examined. Intranasal IL-12 was found to be more effective in the Th2-Th1 shifting of immune response and anti-inflammatory activity in the lung compared to nebulized IL-12 at the given doses. Intranasal IL-12 significantly decreased production of IFN-gamma, eotaxin and LTC4/D4/E4 in the lung and decreased eosinophil infiltration, resulting in attenuated airway hyper-responsiveness in GAL-sensitized (GS) mice. In contrast, intranasal IL-12 significantly increased IFN-gamma production in the thoracic lymph node cultures and decreased the IL-5/IFN-gamma ratio, suggesting a Th2-Th1 shift. Also, intranasal IL-12 increased GAL-specific IgG2a antibody response, while the IgE response remained unaffected. The systemic effects of IL-12 were IFN-gamma dependent. IL-12 induces differential expression of its own receptor beta1 and beta2 subunits in the lung tissues to augment IL-12 responsiveness. Together, these results demonstrate that intranasal IL-12 is effective in shifting the systemic immune response in the direction of Th1 in IFN-gamma-dependent manner, while decreasing pulmonary inflammation and airway reactivity independent of IFN-gamma. Thus, intranasal delivery of IL-12 may provide an approach for the treatment of asthma and may be useful as an adjuvant in local nasal immunotherapy (IT) and in asthma.     

Current role of hybrid CT/angiography system compared with C-arm cone beam CT for interventional oncology

Hybrid CT/angiography (angiography) system and C-arm cone beam CT provide cross-sectional imaging as an adjunct to angiography. Current interventional oncological procedures can be conducted precisely using these two technologies. In this article, several cases using a hybrid CT/angiography system are shown first, and then the advantages and disadvantages of the hybrid CT/angiography and C-arm cone beam CT are discussed with literature reviews.A hybrid CT/angiography system was developed in 1992. Professor Y. Arai, Director of the National Cancer Center, Tokyo, Japan, first introduced this system in Aichi Cancer Center (Nagoya, Japan).¹ This system integrates a CT scanner and an angiography unit, which are arranged in line using a common patient table. This permits CT, conventional fluoroscopy and angiography to be performed on the same table without having to move the patient, thereby omitting the risk of needle and catheter dislocation or compromising sterile conditions owing to patient transportation. This system is used for various interventional oncologic procedures.² Nearly 10 years ago, the initial development of the C-arm cone beam CT technology, in which CT-like images were obtained from a flat-panel detector, was reported. With the improvement in detector technology, C-arm cone beam CT is now being used in various interventions worldwide. These two technologies, which provide cross-sectional imaging as an adjunct to angiography, allow interventional oncological procedures to be precisely conducted.The question is whether there are still any roles for the hybrid CT/angiography system after the introduction of the C-arm cone beam CT. First, this article provides our experience with cases using the hybrid CT/angiography system, along with a review of the previously published literature. Then, the advantages and drawbacks of the hybrid interventional CT/angiography system and C-arm cone beam CT are summarized, and the current role of the hybrid CT/angiography system for interventional oncology is discussed.     

Atelocollagen-mediated systemic delivery prevents immunostimulatory adverse effects of siRNA in mammals

Short interfering RNA (siRNA) is a potent activator of the mammalian innate immune system. When considering possible clinical applications of siRNA for humans, the adverse immunostimulatory effects must also be taken into account. Here, we show that atelocollagen-mediated systemic delivery of siRNA without chemical modifications did not cause any immunostimulation in both animals and human peripheral blood mononuclear cells (PBMCs), even if the siRNA harbored an interferon (IFN)-inducible sequence. In contrast, systemic delivery of immunostimulatory RNA (isRNA)-mediated by a cationic lipid (such as Invivofectamine) induced potent type-I IFNs and inflammatory cytokines. Regarding the mechanism by which the isRNA/atelocollagen complex avoided adverse effects on immunostimulation, we revealed that this complex was not incorporated into PBMCs. On the other hand, Invivofectamine delivered isRNA into PBMCs. The use of either atelocollagen or Invivofectamine as a vehicle elicited significant and undistinguishable therapeutic effects in a contact hypersensitivity (CHS) inflammatory model mouse, when we intravenously injected the siRNA targeting monocyte chemoattractant protein-1 as the complex. For the goal of realizing siRNA-based medicines for humans, atelocollagen is an excellent and promising delivery vehicle, and it has the useful advantage of evading detection by the "radar" of innate immunity.     

A successful diagnostic case of Pneumocystis pneumonia by the loop-mediated isothermal amplification method in a patient with dermatomyositis

Pneumocystis pneumonia (PCP) can occur in patients with many causes of the immunocompromised state other than human immunodeficiency virus (HIV). It is quite difficult to diagnose PCP without HIV because there is no method for detecting Pneumocystis jirovecii. Thus, non-HIV PCP continues to have high mortality. Recently, loop-mediated isothermal amplification (LAMP) is becoming an established nucleic acid amplification method offering rapid, accurate, and cost-effective diagnosis of infectious diseases. We report a non-HIV PCP case successfully diagnosed by the LAMP method. It was previously reported that PCR in BALF specimens had been the most sensitive method in the diagnosis of PCP without HIV. The LAMP method would be more sensitive than conventional PCR and an effective tool in the early diagnosis of PCP.