Further Isolation of a Recombinant Virus (H1N2, Formerly Hsw1N2) from a Pig in Japan in 1980

In September 1980, an outbreak of febrile respiratory disease was observed in a herd of sows (1-2 years of age) in Ehime Prefecture, Japan. Most of the swine showed clinical signs of disease such as depression, anorexia, fever, nasal discharge, and cough. A hemagglutinating agent was isolated from a nasal swab from one of the diseased pigs. By cross-hemagglutination-inhibition and neuraminidase-inhibition tests with antisera to influenza viruses of swine origin, the isolate was identified as an influenza A virus of the H1N2 (former designation, Hsw1N2) subtype, and designated A/swine/Ehime/1/80 (H1N2). Significant antibody rises against the surface antigens of the isolate were found in convalescent swine sera. The distribution of antibody against H1N2 virus in swine sera in Ehime Prefecture was examined. Seven (8%) of 93 sera collected after the outbreak (in 1981) showed antibodies to only H1 and N2 antigens but none of the sera before the outbreak contained such antibodies, indicating that H1N2 virus had been restrictedly prevalent among swine but was not wide-spread until 1981.     

Molecular mechanism underlying muscle mass retention in hibernating bats: Role of periodic arousal

Hibernators like bats show only marginal muscle atrophy during prolonged hibernation. The current study was designed to test the hypothesis that hibernators use periodic arousal to increase protein anabolism that compensates for the continuous muscle proteolysis during disuse. To test this hypothesis, we investigated the effects of 3‐month hibernation (HB) and 7‐day post‐arousal torpor (TP) followed by re‐arousal (RA) on signaling activities in the pectoral muscles of summer‐active (SA) and dormant Murina leucogaster bats. The bats did not lose muscle mass relative to body mass during the HB or TP‐to‐RA period. For the first 30‐min following arousal, the peak amplitude and frequency of electromyographic spikes increased 3.1‐ and 1.4‐fold, respectively, indicating massive myofiber recruitment and elevated motor signaling during shivering. Immunoblot analyses of whole‐tissue lysates revealed several principal outcomes: (1) for the 3‐month HB, the phosphorylation levels of Akt1 (p‐Akt1) and p‐mTOR decreased significantly compared to SA bats, but p‐FoxO1 levels remained unaltered; (2) for the TP‐to‐RA period, p‐Akt1 and p‐FoxO1 varied little, while p‐mTOR showed biphasic oscillation; (3) proteolytic signals (i.e., atrogin‐1, MuRF1, Skp2 and calpain‐1) remained constant during the HB and TP‐to‐RA period. These results suggest that the resistive properties of torpid bat muscle against atrophy might be attained primarily by relatively constant proteolysis in combination with oscillatory anabolic activity (e.g., p‐mTOR) corresponding to the frequency of arousals occurring throughout hibernation. J. Cell. Physiol. 222: 313–319, 2010. © 2009 Wiley‐Liss, Inc.     

Time Adaptation Shows Duration Selectivity in the Human Parietal Cortex

Although psychological and computational models of time estimation have postulated the existence of neural representations tuned for specific durations, empirical evidence of this notion has been lacking. Here, using a functional magnetic resonance imaging (fMRI) adaptation paradigm, we show that the inferior parietal lobule (IPL) (corresponding to the supramarginal gyrus) exhibited reduction in neural activity due to adaptation when a visual stimulus of the same duration was repeatedly presented. Adaptation was strongest when stimuli of identical durations were repeated, and it gradually decreased as the difference between the reference and test durations increased. This tuning property generalized across a broad range of durations, indicating the presence of general time-representation mechanisms in the IPL. Furthermore, adaptation was observed irrespective of the subject’s attention to time. Repetition of a nontemporal aspect of the stimulus (i.e., shape) did not produce neural adaptation in the IPL. These results provide neural evidence for duration-tuned representations in the human brain.     

An Epidermal Growth Factor Motif from Del1 Protein Increases the Efficiency of In Vivo Gene Transfer with a Non-Viral Vector

Increasing the efficiency of gene transfer using non-viral vectors, which have the potential to be safe and economical, would improve upon available options for gene therapy. We previously reported that the third EGF motif of the extracellular matrix protein Del1 (E3) increases the transfection efficiency of non-viral vector methods. Here, we asked if E3 could increase the in vivo transfection efficiency of a polyplex-based approach. To test this, cDNA encoding a heat-stable alkaline phosphatase (AP) was first injected intravenously into mice along with recombinant E3. After 24 h, exogenous AP activity in serum was measured. We found that the introduction of E3 resulted in 50 % more AP activity as compared to the control. We next tested transfection into a tumour explant of SCCKN cells, an oral carcinoma-derived cell line. To do this, a cDNA encoding yellow fluorescent protein was locally injected into a tumour explant, followed by local injection of recombinant E3. Use of E3 increased the number of transfected cells to 2.5 times that of the control. Histochemical staining revealed that E3-induced apoptosis in a tumour explant. The data suggest that E3 might be a useful tool for cancer gene therapy using non-viral vectors.