Expression profile of Notch-1 in mechanically overloaded plantaris muscle of mice

AimWe investigated the expression pattern of Notch-1 in normal and hypertrophied plantaris muscle of mice.Main methodsWe performed immunofluorescence of both Notch-1 and the Notch-1-linking molecules.Key findingsImmunofluorescence labeling revealed Notch-1 protein in Pax7-positive satellite cells during days 2–6. We observed clear co-localization between Notch-1 and myogenin (4.9 ± 1.3%) in the hypertrophied muscle at 4 days. Several mononuclei (possibly satellite cells) possessed both Notch-1 and Foxo1 in the plantaris muscle subjected to mechanical overloading (4.1 ± 1.2%).SignificanceNotch-1 may play an important role in the maintenance of quiescent satellite cells.     

Neural interaction between galanin-like peptide (GALP)- and luteinizing hormone-releasing hormone (LHRH)-containing neurons

Galanin-like peptide (GALP), commonly known as an appetite-regulating peptide, has been shown to increase plasma luteinizing hormone (LH) through luteinizing hormone-releasing hormone (LHRH). This led us to investigate, using both light and electron microscopy, whether GALP-containing neurons in the rat brain make direct inputs to LHRH-containing neurons. As LHRH-containing neurons are very difficult to demonstrate immunohistochemically with LHRH antiserum without colchicine treatment, we used a transgenic rat in which LHRH tagged with enhanced green fluorescence protein facilitated the precise detection of LHRH-producing neuronal cell bodies and processes. This is the first study to report on synaptic inputs to LHRH-containing neurons at the ultrastructural level using this transgenic model. We also used immunohistochemistry to investigate the neuronal interaction between GALP- and LHRH-containing neurons. The experiments revealed that GALP-containing nerve terminals lie in close apposition with LHRH-containing cell bodies and processes in the medial preoptic area and the bed nucleus of the stria terminalis. At the ultrastructural level, the GALP-positive nerve terminals were found to make axo-somatic and axo-dendritic synaptic contacts with the EGFP-positive neurons in these areas. These results strongly suggest that GALP-containing neurons provide direct input to LHRH-containing neurons and that GALP plays a crucial role in the regulation of LH secretion via LHRH.     

Disinfection of Microorganisms by Use of Electrochemically Regenerated Periodate

A new method for disinfection of microorganisms by electrochemically regenerated periodate was developed. Oxidation of iodate to periodate was observed at 1.25 V versus a silver/silver chloride electrode in a cyclic voltammogram of potassium iodate. When 1.25 V was applied in 1.0 mM potassium iodate, approximately 4-log inactivation of Escherichia coli was observed in 30 min.     

X-ray Structure Analysis and Characterization of AFUEI,an Elastase Inhibitor from Aspergillus fumigatus

Elastase from Aspergillus sp. is an important factor for aspergillosis. AFUEI is an inhibitor of the elastase derived from Aspergillus fumigatus. AFUEI is a member of the I78 inhibitor family and has a high inhibitory activity against elastases of Aspergillus fumigatus and Aspergillus flavus, human neutrophil elastase and bovine chymotrypsin, but does not inhibit bovine trypsin. Here we report the crystal structure of AFUEI in two crystal forms. AFUEI is a wedge-shaped protein composed of an extended loop and a scaffold protein core. The structure of AFUEI shows remarkable similarity to serine protease inhibitors of the potato inhibitor I family, although they are classified into different inhibitor families. A structural comparison with the potato I family inhibitors suggests that the extended loop of AFUEI corresponds to the binding loop of the potato inhibitor I family, and AFUEI inhibits its cognate proteases through the same mechanism as the potato I family inhibitors.     

A new culturing method for production of filamentous hemagglutinin of Bordetella pertussis

The addition of cyclodextrins, especially heptakis (2,6-O-dimethyl)β-cyclodextrin (MeβCD), to synthetic medium, such as Stainer-Scholte medium (D.W. Stainer and M.J. Scholte, J. Gen. Microbiol. 63: 211–220) greatly stimulated the production of filamentous hemagglutinin (F-HA) by Bordetella pertussis Tohama phase I under shaking conditions. Purified F-HA from this culturing system was demonstrated immunochemically and morphologically to be identical with that from static culture.     

Early events in retrovirus XMRV infection of the wild-derived mouse Mus pahari

A novel gammaretrovirus, xenotropic murine leukemia virus-related virus (XMRV), has been identified in patients with prostate cancer and in patients with chronic fatigue syndromes. Standard Mus musculus laboratory mice lack a functional XPR1 receptor for XMRV and are therefore not a suitable model for the virus. In contrast, Gairdner's shrew-mice (Mus pahari) do express functional XPR1. To determine whether Mus pahari could serve as a model for XMRV, primary Mus pahari fibroblasts and mice were infected with cell-free XMRV. Infection of cells in vitro resulted in XMRV Gag expression and the production of XMRV virions. After intraperitoneal injection of XMRV into Mus pahari mice, XMRV proviral DNA could be detected in spleen, blood, and brain. Intravenous administration of a green fluorescent protein (GFP) vector pseudotyped with XMRV produced GFP(+) CD4(+) T cells and CD19(+) B cells. Mice mounted adaptive immune responses against XMRV, as evidenced by the production of neutralizing and Env- and Gag-specific antibodies. Prominent G-to-A hypermutations were also found in viral genomes isolated from the spleen, suggesting intracellular restriction of XMRV infection by APOBEC3 in vivo. These data demonstrate infection of Mus pahari by XMRV, potential cell tropism of the virus, and immunological and intracellular restriction of virus infection in vivo. These data support the use of Mus pahari as a model for XMRV pathogenesis and as a platform for vaccine and drug development against this potential human pathogen.     

Synthesis of Pullulan by Acetone-dried Cells and Cell-free Enzyme from Pullularia pullulans,and the Participation of Lipid Intermediate

It was demonstrated that the polysaccharide, pullulan, was synthesized from sucrose by acetone-dried cells of Pullularia pullulans or from UDPG by cell-free enzyme preparations prepared from the organism. The pullulan formed was estimated by precipitation with ethanol, and determining maltotriose produced after treating the precipitate with Aerobacter isoamylase (pullulanase). Acetone cells (5 g) shaken with 200 ml of 10% sucrose produced over 250 mg of pullulan per 100 ml after 90 hr at 30°C and pH 6.0. Cell-free enzyme produced pullulan from UDPG in the presence of ATP. ATP was essential for the biosynthesis, and ADPG could not replace for UDPG.

In addition, it was observed that a lipid containing glucose residue was formed during, the reaction. The nature of this glucolipid was examined, and possible participation of a lipid intermediate was assumed in the pullulan biosynthesis.     

Classification of Tobaccos with Analytical Data of Nitrogen containing Compounds in Their Headspace Volatiles

In order to examine the relationship between tobacco aroma and the nitrogen-containing compounds in the tobacco headspace volatiles, the volatiles of flue-cured, Burley and Turkish tobaccos collected with Tenax GC were analyzed by a gas chromatograph equipped with a flame thermionic detector. Of the 21 compounds identified in the chromatogram, 2,5-dimethylpyridine, 2,4-dimethylpyridine, pyrrole and N-methylpyrrole have not been previously reported as present in the tobacco headspace volatiles. By principal component analysis and stepwise discriminant analysis, three principal components and discriminant functions with four peaks were obtained. The results of these statistical analyses classified the samples into each variety respectively.