Development of new drug delivery system for protein drugs using silicone (I).

A novel technique, by which protein drugs effective in small doses can be released over a long period, was developed using silicone and a water-soluble substance. In this study, interferon (IFN) was used as a model of the protein drugs. The IFN-silicone formulation released IFN over long periods of time in vitro and suppressed tumor growth in nude mice for about 100 days after a single administration. This indicates that physiologically active IFN is released over a prolonged period of time from the IFN-silicone formulation in vivo. Silicone formulations are expected to be a practically feasible sustained-release formulation.     

Study on accelerated evaluation system for release profiles of covered-rod type silicone formulation using indomethacin as a model drug.

The purpose of this study was to establish a method allowing rapid evaluation in vitro of the profiles of drug release from covered-rod type silicone formulation (CR silicone formulation), which releases drug for a prolonged period of time. Three CR silicone formulations containing indomethacin (IDM) with different release profiles were used in this study. The release of IDM was accelerated in a mixture of methanol and water (MeOH/water) compared with in phosphate-buffered saline (PBS) added by Tween 20 (PBS-based solvent). The velocity of IDM release varied depending on the composition of the MeOH/water. The change in release velocity was dependent on the solubility of IDM and the permeability of IDM through the silicone membrane. In all the tested formulations, the release rates of IDM estimated in 90% (v/v) MeOH/water were equally 14.6 times faster than those estimated in PBS-based solvent. Release of IDM from the cross-sections and lateral side evaluated by a bi-directional elution cell were accelerated in the MeOH/water in a similar degree. By introducing a common factor to shorten the time axis in all formulations, a fairly good agreement was observed between the two release profiles obtained in the accelerated MeOH/water system and the usual PBS-based solvent system. These results indicate that MeOH/water system enables to reduce the period for evaluation of profiles of drug release from CR silicone formulations in reflecting their release characteristics in usual PBS-based solvent system.     

Isolated inflammatory myopathy with rimmed vacuoles presenting with dropped head

We describe an unusual case of inflammatory myopathy with rimmed vacuoles associated with dropped head syndrome. Muscle biopsy in our patient revealed variations in fiber size with fiber necrosis and regeneration, accompanied by many rimmed vacuoles and areas of endomysial cell infiltration. Electron microscopy demonstrated autophagic vacuoles and tubulofilamentous inclusions. This myopathy can cause dropped head syndrome in a subgroup of patients.     

Craniospinal irradiation using helical tomotherapy: evaluation of acute toxicity and dose distribution

The purpose of this study was to evaluate acute toxicity of craniospinal irradiation (CSI) using helical tomotherapy (HT) and compare its dose distribution with that of conventional linac-based plans. Twelve patients with various brain tumors were treated with HT-CSI. Median patient age was 14 years (range: 4-37 years). Median CSI dose was 30.6 Gy in 18 fractions (range: 23.4-40 Gy in 13-25 fractions). Toxicities were assessed according to the Common Terminology Criteria for Adverse Events version 4.0. Before CSI, 11 patients (92%) received neoadjuvant chemotherapy, so acute toxicity was evaluated by comparing patient status before and after CSI. HT-CSI plans were compared with linac-based CSI plans made using Pinnacle(3) planning system in 9 patients. All patients completed planned CSI without interruption. Grade 3 or higher toxicities were leukopenia seen in 11 patients (92%), anorexia in 6 (50%), anemia in 5 (42%), and thrombopenia in 5 (42%). Administration of granulocyte colony-stimulating factor, platelet transfusion and total parenteral nutrition were required in 8 (67%), 5 (42%) and 5 (42%) patients, respectively. HT plans were superior to linac-based plans in terms of homogeneity and conformality in planning target volume (PTV). For most organs at risk (OARs), volumes receiving more than 10 Gy (V10 Gy) or 20 Gy (V20 Gy) were lower in HT plans. However, HT plans significantly increased mean doses to the lung, kidneys and liver, and V5 Gy of 6 OARs including the lung. Despite intensive neoadjuvant chemotherapy, acute toxicity of HT-CSI was acceptable. HT provided better dose distribution in PTV than conventional linac. In most OARs, smaller volumes received >10-20 Gy in HT plans, although larger volumes received 5-10 Gy.     

Frequent mutations in Japanese patients with acid maltase deficiency

We screened 22 Japanese patients with acid maltase deficiency (seven with the infantile type, eight with the juvenile type and seven with the adult type) for three previously described mutations, D645E, S529V and R672Q, and a novel mutation, R600C. Although D645E has been reported to be common in Chinese patients with the infantile type, only three of 44 alleles (two of 14 infantile type alleles) from Japanese patients harbored the D645E mutation. The S529V mutation was identified in six of 14 alleles from adult-onset patients. None of the infantile or juvenile patients harbored the S529V mutation. Therefore, S529V apparently results in the adult type disease and is common in Japanese adult-onset patients. R672Q was identified in two pairs of siblings with the juvenile type. A novel mutation, R600C, was identified in eight of 22 patients (nine of 44 alleles). Therefore, R600C is another common Japanese mutation occurring at a CpG dinucleotide “hot spot”. Homozygosity for this mutation apparently results in the infantile phenotype. Genetic diagnosis by detecting these four mutations might be feasible for most Japanese patients with acid maltase deficiency.     

A lipophilic statin, pitavastatin, suppresses inflammation-associated mouse colon carcinogenesis

3-Hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors are known to modulate carcinogenesis. In this study, we investigated whether a lipophilic HMG-CoA reductase inhibitor pitavastatin suppresses inflammation-related mouse colon carcinogenesis. Male CD-1 (ICR) mice were initiated with a single intraperitoneal injection of azoxymethane (AOM, 10 mg/kg body weight) and promoted by 2% (w/v) dextran sodium sulfate (DSS) in drinking water for 7 days. The experimental diets containing pitavastatin at 2 dose levels (1 and 10 ppm) were fed to male CD-1 (ICR) mice for 17 weeks, staring 1 week after the cessation of DSS exposure. The effects of dietary pitavastatin on colonic tumor development were assessed at Weeks 5, 10 and 20. Feeding with pitavastatin at both doses significantly inhibited the multiplicity of colonic adenocarcinoma at Week 20. Furthermore, the treatment significantly lowered the positive rates of proliferating cell nuclear antigen and increased the apoptotic index in the colonic epithelial malignancies. The treatment also reduced nitrotyrosine-positivity in the colonic mucosa. Our findings thus show that pitavastatin is effective in inhibiting colitis-related colon carcinogenesis through modulation of mucosal inflammation, oxidative/nitrosative stress, and cell proliferation.     

A pathophysiological study of macular mutant mouse as a model of human Menkes kinky hair disease. I. Copper contents and copper dependent enzyme activities in various organs

The wet weight, copper content, mitochondrial electron-transfer complexes and 2',3'-cyclic nucleotide 3'-phosphohydrolase (CNPase) were measured in various organs including brain, liver, kidney, and heart in macular mutant mice which are considered to be an appropriate model for human Menkes kinky hair disease (MKHD). Copper contents were decreased markedly in liver, brain, and heart. However a significant increase was noted in kidney, suggesting a disproportionate distribution of copper contents in each organ in this mutant mouse. Regarding mitochondrial electron-transfer complexes, only cytochrome c oxidase, a copper dependent enzyme, was found to be decreased in heart and brain. This alteration in the brain was already demonstrated at 2 days. CNPase was not decreased in its activity at 7 days, but decreased at 14 days, supporting progressive demyelination. These results suggested that this mutant mouse would be a useful animal model for clarifying the pathogenesis in human MKHD.     

A pathophysiological study of macular mutant mouse as a model of human Menkes kinky hair disease. II. Analysis of brain metabolism using 31P- and 1H-nuclear magnetic resonance spectroscopy

We studied the brain metabolism in macular mutant mice (Ml/y, +/y), an appropriate model of Menkes kinky hair disease, using 31P- and 1H-NMR spectroscopy to clarify the pathophysiological mechanisms of disturbed nervous function. An analysis of in vivo 31P-NMR spectra showed a decreased phosphocreatine (PCr)/inorganic phosphate (Pi) ratio and decreased ATP levels and decreased intracellular pH in Ml/y mice at 9 days, suggesting energy failure in the brain. This associated decline in ATP levels may reflect multiple causative factors including disturbed mitochondrial respiration and ischemia secondary to circulatory failure. Brain metabolites, including PCr, creatine, lactate and 7 amino acids were easily detectable quantitatively and qualitatively by in vitro 1H-NMR spectrum. An elevation in lactate levels and a decline in PCr/creatine ratio in Ml/y mice at 9 days were also noted with an in vitro study, supporting the in vivo data. NMR spectroscopy is a useful and promising tool to obtain the information on brain metabolism.     

Fine-needle aspiration cytology of xanthogranulomatous pyelonephritis

Fine-needle aspiration cytology of xanthogranulomatous pyelonephritis in a fifty-seven-year-old Japanese woman is reported. Foamy cells and cells showing a gland-like pattern originating from degenerative renal tubules were found in the aspirated smears. Multinucleated giant cells and cells with pale yellowish cytoplasm were seen in the imprint smears at operation. These findings were diagnostic for xanthogranulomatous pyelonephritis. The cytologic diagnostic differences among xanthogranulomatous pyelonephritis, well-differentiated renal cell carcinoma, and renal oncocytoma are also described.