On the Magnetic Properties of Sintered Iron

An improved method of producing iron powder briquette from Fe(CO)_5 was developed. The method enables us to get iron briquette superior in magnetic properties to any briquette produced by other industrial method. The briquette was prepared from oxide powder, obtained by a specially arranged oxidizing apparatus for liquid carbonyl. The oxide was reduced in hydrogen stream, and moulded to a troidal form with the pressure of 6t/cm^2 ; the compact thus obtained was sintered at 450°, 800°, 900°, 1, 000°and 1, 100°. The superiority of the briquette in magnetic properties was found in comparison with other briquettes, which were prepared from carbonyl iron and electrolytic iron powder under the same condition

Hypertension, hypertriglyceridemia, and impaired endothelium-dependent vascular relaxation in mice lacking insulin receptor substrate-1.

Insulin resistance is often associated with atherosclerotic diseases in subjects with obesity and impaired glucose tolerance. This study examined the effects of insulin resistance on coronary risk factors in IRS-1 deficient mice, a nonobese animal model of insulin resistance. Blood pressure and plasma triglyceride levels were significantly higher in IRS-1 deficient mice than in normal mice. Impaired endothelium-dependent vascular relaxation was also observed in IRS-1 deficient mice. Furthermore, lipoprotein lipase activity was lower than in normal mice, suggesting impaired lipolysis to be involved in the increase in plasma triglyceride levels under insulin-resistant conditions. Thus, insulin resistance plays an important role in the clustering of coronary risk factors which may accelerate the progression of atherosclerosis in subjects with insulin resistance

Germline mutation of HRPT2 in patients with HPT

Background A subset of familial isolated primary hyperparathyroidism (FIHP) is a variant of hyperparathyroidism-jaw tumor syndrome (HPT-JT). Aim/Patients and Methods We investigated the involvement of the HRPT2, MEN1, and CASR genes in provisional 11 FIHP families and 2 HPT-JT families. Results Germline mutations of HRPT2 were found in 2 of 11 FIHP families and 1 of 2 HPT-JT families. One FIHP family with parathyroid carcinoma and atypical adenomas, and another FIHP family with cystic parathyroid adenoma had novel frameshift mutations of 518-521del and 62-66del, respectively. In a patient with HPT-JT, a de novo germline mutation of 39delC was detected. Novel somatic HRPT2 mutations of 70-73del and 95-102del were found in 2 of 5 parathyroid tumors in a family with 518-521del mutation. Biallelic inactivation of HRPT2 by a combination of germline mutation and somatic mutation was confirmed in parathyroid tumors. The finding that 2 families diagnosed with FIHP carried HRPT2 mutations suggests that they have occult HPT-JT. In the remaining 10 families, one family had a missense MEN1 mutation. No mutations of CASR were detected. Conclusion Our results confirm the need to test for HRPT2 in FIHP families, especially in those with parathyroid carcinomas, atypical adenomas, or adenomas with cystic change

Identification and structural analysis of C-terminally truncated collapsin response mediator protein-2 in a murine model of prion diseases

<p>Abstract</p> <p>Background</p> <p>Prion diseases are fatal neurodegenerative disorders that accompany an accumulation of the disease-associated form(s) of prion protein (PrP^Sc) in the central nervous system. The neuropathological changes in the brain begin with focal deposits of PrP^Sc, followed by pathomorphological abnormalities of axon terminal degeneration, synaptic loss, atrophy of dendritic trees, and eventual neuronal cell death in the lesions. However, the underlying molecular basis for these neuropathogenic abnormalities is not fully understood.</p> <p>Results</p> <p>In a proteomic analysis of soluble proteins in the brains of mice challenged intracerebrally with scrapie prion (Obihiro I strain), we found that the amount of the full-length form of collapsin response mediator protein-2 (CRMP-2; 61 kDa) decreased in the late stages of the disease, while the amount of its truncated form (56 kDa) increased to comparable levels observed for the full-length form. Detailed analysis by liquid chromatography-electrospray ionization-tandem mass spectrometry showed that the 56-kDa form (named CRMP-2-ΔC) lacked the sequence from serine⁵¹⁸to the C-terminus, including the C-terminal phosphorylation sites important for the regulation of axonal growth and axon-dendrite specification in developing neurons. The invariable size of the mRNA transcript in Northern blot analysis suggested that the truncation was due to post-translational proteolysis. By overexpression of CRMP-2-ΔC in primary cultured neurons, we observed the augmentation of the development of neurite branch tips to the same levels as for CRMP-2^T514A/T555A, a non-phosphorylated mimic of the full-length protein. This suggests that the increased level of CRMP-2-ΔC in the brain modulates the integrity of neurons, and may be involved in the pathogenesis of the neuronal abnormalities observed in the late stages of the disease.</p> <p>Conclusions</p> <p>We identified the presence of CRMP-2-ΔC in the brain of a murine model of prion disease. Of note, C-terminal truncations of CRMP-2 have been recently observed in models for neurodegenerative disorders such as ischemia, traumatic brain injury, and Wallerian degeneration. While the structural identity of CRMP-2-ΔC in those models remains unknown, the present study should provide clues to the molecular pathology of degenerating neurons in prion diseases in connection with other neurodegenerative disorders.</p