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T 2 fluid-attenuated inversion recovery (FLAIR) using inversion recovery pulse to suppress cerebrospinal fluid signal needs adequate T 1 recovery time after data acquisition, otherwise, the T 2 -weighted contrast in brain tissue will get lower. Over 10000 ms of repetition time (TR) is recommended for the 1.5 T MR scanner, so it is difficult to shorten the imaging time. We verified whether T 2 FLAIR combined with the magnetization transfer contrast (MTC) pulse shows better gray-to-white matter (GM/WM) and lesion-to-normal tissue contrasts even when the TR is shortened compared to the conventional T 2 FLAIR. Optimal parameters of the MTC pulse were determined with a self-produced phantom, which modeled on cerebral cortical gray and white matters. GM/WM contrasts of the phantom were measured in T 2 FLAIR with the MTC pulse while decreasing TR gradually from 10000 ms to 6500 ms. Although GM/WM contrast of the phantom in T 2 FLAIR with the MTC pulse gradually decreased as the TR got shortened, the T 2 FLAIR with the MTC pulse of 6500 ms of TR still showed 27% higher contrast than the conventional T 2 FLAIR (TR 10000 ms). GM/WM contrast in T 2 FLAIR with the MTC pulse was improved also in healthy volunteers, but improvement in thalamo-medullary contrast was less than that of cerebral cortico-medullary and putamino-medullary contrasts. It seems to be because thalamus, which is a deep gray matter, shows a higher MTC effect than other gray matters. Thus, it is necessary to note that the tissue contrast might differ between T 2 FLAIR with the MTC pulse and the conventional T 2 FLAIR. Because general lesions with an elongated T 2 value show lower MTC effect compared to the normal brain tissue, a clinical case with thalamic lesion showed that the lesion-to-normal tissue contrast improved in T 2 FLAIR with the MTC pulse of 6500 ms of TR. Although it is necessary to note the difference in contrast between some tissues, T 2 FLAIR with the MTC pulse improves GM/WM and lesion-to-normal tissue contrasts even when the TR is shortened compared to the conventional T 2 FLAIR, and it enables to shorten the imaging time.

Construction of three-dimensional (3D) tissues with perfusable vascular networks remains a major challenge in the field of tissue engineering. Although various sacrificial templates have been employed to fabricate the vascular networks, there are some issues with respect to cytocompatibility, structural controllability, and degradability for the achievement of precisely controlled vasculatures without cytotoxicity. Here, we demonstrate a naturally occurring polysaccharide, gellan gum (GG), as a sacrificial template material due to its unique character. GG showed rapid gelation at 30-50 °C during the cooling process depending on the concentration of bivalent calcium ions by intermolecular ionic cross-linking and subsequent double-helix formation of GG molecules. Although chelate agents such as EDTA are generally effective in decomposing ionic cross-linking gels, e.g., alginate gel, they usually show cytotoxicity. In the case of GG gel, the gels could not be decomposed by the chelate agents but were easily decomposed by Tris-HCl buffer (pH = 7.4), which is a basic molecule with high cytocompatibility. We finally fabricated straight vascular tubes in 3D-gelatin gels and then demonstrated perfusion of human whole blood at 3.0 cm/s for 2 h. Since the complex vascular networks were constructed by 3D inkjet printing of the GG solution, GG would be useful as a structurally controllable and easily decomposable sacrificial material with cytocompatibility.

Purpose: Homogeneity of static magnetic field (B(0)) is unstable for head and neck magnetic resonance (MR) examination; consequently, chemical shift selective fat suppression becomes inhomogeneous. There is a commercially available additional pad to attenuate the B(0) inhomogeneity, but it is expensive. It has been reported that uncooked rice can be used as a material in the pad, but it has hygienic and weight problems. We searched for a material which can replace the uncooked rice, and evaluated its performance., Method: After filling various materials into the cylindrical phantom, each material was evaluated by image distortion of gradient filed echo and spin echo single-shot echo planar images. A prototype additional pad was made with a material which showed less image distortion in the phantom experiment and is easily available in clinical examination. For comparison, an uncooked rice pad with the same volume was also prepared. Fat suppressed head and neck magnetic resonance imaging (MRI) of normal volunteers were visually compared when the three additional pads, including the commercial product, were used or not., Result: The polystyrene ball bullet (BB bullet) was adopted as a material for the additional pad. The improvement of the fat suppression in the head and neck MRI was almost the same between the three additional pads. BB bullet pad was the lightest., Conclusion: BB bullet can be used as a material of additional pad attenuating the B(0) inhomogeneity instead of uncooked rice.

Purpose: To evaluate whether short-tau inversion-recovery (STIR) fat suppression is worthwhile in non-contrast-enhanced respiration-triggered free-breathing time-spatial labeling inversion pulse (Time-SLIP) renal magnetic resonance angiography (MRA) compared with chemical shift selective (CHESS) fat suppression., Materials and Methods: Simulation-based analyses of inversion time (TI) for spatial-selective inversion-recovery (ssIR) pulse and breathing rate were performed, and confirmed on a phantom and in human subjects using a three-dimensional (3D) coherent steady-state free precession (SSFP) sequence on a 1.5T Toshiba scanner., Results: The STIR fat suppression successfully suppressed signals from the intestines and parenchymous organs and provided better contrast between the arteries and the background, although an extension of TI was required for the ssIR pulse when a patient's respiration was extremely slow., Conclusion: STIR fat suppression provides better renal artery contrast than CHESS fat suppression in non-contrast free-breathing Time-SLIP MRA; it is also an effective screening tool for renal artery stenosis because of the lack of interference from intestinal signals. However, close attention is needed if the patient has slow respiration. As the TI for the ssIR pulse decreases, the STIR method requires faster-paced respiration.

Cardiovascular involvements in antiphospholipid antibody syndrome have been recognized as a major complication of this disease. Furthermore, some papers report bioprosthetic heart valve also seems to be affected. A 32-year-old female with aortic regurgitation presented to our hospital. Further examination revealed high titer of anticardiolipin beta 2 glycoprotein 1 antibody, and she was diagnosed as having primary antiphospholipid antibody syndrome since the patient failed to match the criteria of systemic lupus erythematosus. Cardiopulmonary bypass was uneventfully conducted under systemic heparinization of usual dosage. Administration of warfarin sodium was started on the third postoperative day, and international normalized ratio was controlled from 2.0 to 2.5. On echocardiographic examination at 1 month, mean systolic gradient was 17 mmHg. Although transesophageal echocardiography at 2 years after surgery revealed no sign of valvular destruction or sclerosis, transaortic gradient had increased to 26 mmHg. Bioprosthetic stenosis was suspected probably due to pannus formation and the patient may have to undergo another valve replacement in the near future.

Background: Coagulation and inflammation are both important processes that contribute to glomerular injury. The present study was performed to evaluate the effects of recombinant human soluble thrombomodulin (RHS-TM) in a lethal model of thrombotic glomerulonephritis and to investigate the possible mechanisms., Methods: Thrombotic glomerulonephritis was induced in rats by administration of lipopolysaccharide and rabbit anti-rat glomerular basement membrane antibody. One hour later, RHS-TM or heparin was administered, and the histological findings, renal functions, and coagulation parameters were evaluated. To evaluate the contribution of carboxypeptidase R (CPR) to the results obtained in rats treated with RHS-TM, plasma CPR levels were measured. Then, carboxypeptidase inhibitor (CPI), which prevents the function of CPR, was administered., Results: Massive glomerular thrombosis and lung hemorrhage developed within five hours of disease induction, and all rats died within 24 hours. RHS-TM (3 mg/kg) prevented the progression of the disease and all rats survived. Heparin (250 U/kg/h) showed similar anti-thrombotic effect, but induced massive hemorrhage in the lungs or stomach. RHS-TM attenuated leukocyte/neutrophil infiltration in the glomerulus but heparin did not, suggesting that RHS-TM has anti-inflammatory properties. CPR levels in plasma were about threefold higher in rats treated with RHS-TM compared to those in rats treated with heparin. Furthermore, the inhibitory effect of RHS-TM on leukocyte/neutrophil infiltration was significantly diminished by injection of CPI., Conclusion: RHS-TM effectively attenuates the injuries of thrombotic glomerulonephritis in rats. The results indicate that RHS-TM, in addition to its anti-thrombotic action, may exert its anti-inflammatory properties by converting proCPR to CPR, which then inactivates anaphylatoxins. RHS-TM is a potential novel therapeutic tool for thrombotic glomerular injury and related disorders.

A 22-year-old man with subacute necrotizing-encephalomyelopathy (SNE; Leigh's disease) was diagnosed as having progressive renal dysfunction. The clinical diagnosis of Leigh's disease was obtained by the typical central nervous lesions, abnormalities in other organs, and increased lactate concentrations in blood and cerebrospinal fluid. We performed an open biopsy of the right kidney. Light microscopic studies of the renal specimen showed diffuse glomerulocystic kidney (GCK) with tubulointerstitial damage. Electron microscopic examination showed marked swelling and increase in the number of mitochondria of the renal tubular epithelial cells. Therefore, it is suggested that mitochondrial disease seems to play an important role in developing GCK.

The presence of plasma proteins in the tubular lumen has variety of adverse effects on the tubular cells. Among various plasma proteins filtered through glomerular barrier, complement has been proven as the possible candidate inducing tubulointerstitial injury. To study the role of intratubular complement activation in proteinuric patients, complement activation products (CAP) at C3 level (iC3b and Bb) and C9 level (membrane attack complex) were measured in both plasma and urine of patients with minimal change nephrotic syndrome (MCNS), focal glomerular sclerosis, IgA nephropathy, membranous nephropathy, and diabetic nephropathy. For evaluation of the effect of metabolic acidosis on the intratubular complement activation, urinary CAP were measured before and after sodium bicarbonate administration in patients with renal insufficiency. The following results were obtained: (1) Patients with focal glomerular sclerosis and diabetic nephropathy showed the highest level of urinary CAP excretion rate (unit/creatinine), while MCNS revealed no increase. (2) Patients with membranous nephropathy showed a unique finding, i.e., isolated increase of membrane attack complex excretion. (3) There was no significant correlation between urine and plasma levels of CAP. (4) Except for MCNS patients, the urinary excretion rate of CAP significantly increased when the level of proteinuria exceeded the nephrotic range, and it was significantly correlated with the serum creatinine level. (5) Urinary CAP excretion rate significantly decreased 2 wk after sodium bicarbonate administration without affecting the level of proteinuria or plasma CAP. These results suggest that the degree of intratubular complement activation correlates with the level of proteinuria, type of glomerular disease, impairment of renal function, and metabolic acidosis.

Radionuclide ventriculographic and echocardiographic assessments of left ventricular cardiac function were studied in 46 long-term maintenance hemodialysis patients, and comparison of cardiac function pre- and post-parathyroidectomy in 10 hemodialysis patients with secondary hyperparathyroidism was investigated. In long-term hemodialysis patients, impairment of cardiac function was observed in 80.4%. In an overall study of 46 patients, no correlation between intact parathyroid hormone (iPTH) level and left ventricular ejection fraction (LVEF) was observed, but a significant (p < 0.05) negative correlation was observed in patients with an iPTh blood level over 200 pg/ml. A negative correlation between fractional fiber shortening and an iPTh level over 200 pg/ml was observed (p < 0.05). There was neither a correlation between the iPTH level and left ventricular (LV) mass, nor was there a correlation between the iPTH level and wall thickness. After parathyroidectomy, systolic and diastolic blood pressure, cardiothoracic ratio, LVEF, and LV mass decreased significantly (p < 0.05), but no significant difference was detected in cardiac thickness. In summary, the present data suggest that high levels over 200 pg/ml of the iPTH in long-term hemodialysis patients adversely affect the myocardial function, induce cardiac hypertrophy and cause high arterial blood pressure. After parathyroidectomy, the cardiac function improved with a reduction of cardiac mass and an improvement of cardiac contraction.