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The use of vaccines is the most effective and reliable method for the prevention of viral infections. However, research on evaluation of effective therapeutic agents for use in treatment after infection is necessary. Zanamivir was administered through inhalation for treatment of pandemic influenza A/H1N1 in 2009. However, the emergence of drug-resistant strains can occur rapidly. Alloferon, an immunomodulatory drug developed as an NK cell activator, exerts antiviral effects against various viruses, particularly influenza viruses. Therefore, alloferon and zanamivir were administered in combination in an effort to improve the antiviral effect of zanamivir by reducing H1N1 resistance. First, we confirmed that administration of combined treatment would result in effective inhibition of viral proliferation in MDCK and A549 cells infected with H1N1. Production of IL-6 and MIP-1α in these cells and the activity of p38 MAPK and c-Jun that are increased by H1N1 were inhibited by combined treatment. Mice were then infected intranasally with H1N1, and examination of the antiviral efficacy of the alloferon/zanamivir combination was performed. The results showed that combined treatment after infection with H1N1 prevented weight loss, increased the survival rate, and improved lung fibrosis. Combined treatment also resulted in reduced infiltration of neutrophils and macrophages into the lungs. Combined treatment effectively inhibited the activity of p38 MAPK and c-Jun in lung tissue, which was increased by infection with H1N1. Therefore, the combination of alloferon/zanamivir effectively prevents the development of H1N1-mediated inflammation in the lungs by inhibiting the production of inflammatory mediators and migration of inflammatory cells into lung tissue. [ABSTRACT FROM AUTHOR]

Based on the structure of limipterin (Cha, Pfleiderer, and Yim, Helv, Chim. Acta, 78: 600-614. 1995 the biosynthetic pathway for the newly identified pterin glycoside was investigated. It was demonstrated that tetrahydrolimipterin (H4 -limipterin) can be synthesized from GTP by the enzymes GTP cyclohydrolase I, 6-pyruvoyltetrahydropterin (PTP) synthase, sepiaptcrin reductase and limipterin synthase, present in the extract of Chlorobium limicola. Limipterin synthase (UDP-N -acetylglucosamine:5 ,6,7 ,8-tetrahydro-L-biopterin 2'-O-β-N-acetylglucosaminyl transferase) catalyzed the condensation of tetrahydrobiopterin (H4-biopterin) with UDP-N-acetylglucosamine in the presence of dithiothreitol and MnCl2. It could also produce D-tepidopterin, [1-O-(D-threo- biopterin-2'-yl)- β-N -acetylglucosamine] when 5,6,7 ,8-tetrahydro-D-threobiopterin and UDP-N-acetylglucosamine were used as substrates . Substrate analogues such as UTP, UDP and UDP-Nacetylgalactosamine inhibit the enzyme activity. The Km values for tetrahydrobiopterin and UDP-N-acetylglucosamine were 42.2 μM and 124.3 μM, respectively. Optimum pH and temperature were pH 8.0 and 37°C. The molecular weight of the enzyme was calculated to be 46,300 dalton from a calibrated Superdex 75 and the subunit molecular weight was estimated at 46,000 dalton by SDS-PAGE. These results suggest that limipterin synthase exists as a monomer. Biosynthetic intermediates of H4-limipterin such as N2NTP , 6-PTP, and H4-biopterin were identified in vitro using purified GTP cyclohydrolase I, PTP synthase, sepiapterin reductase, and limipterin synthase. From the HPLC and TLC analyses of the enzymic intermediater, it could be concluded that H4-limipterin comes from GTP by way of H4-biopterin in Chlorobium limicola.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.cell.2010.01.009 Byline: Hyun Ae Woo (1), Sun Hee Yim (1), Dong Hae Shin (1), Dongmin Kang (1), Dae-Yeul Yu (2), Sue Goo Rhee (1) Keywords: SIGNALING; PROTEINS Abstract: Despite its toxicity, H.sub.2O.sub.2 is produced as a signaling molecule that oxidizes critical cysteine residues of effectors such as protein tyrosine phosphatases in response to activation of cell surface receptors. It has remained unclear, however, how H.sub.2O.sub.2 concentrations above the threshold required to modify effectors are achieved in the presence of the abundant detoxification enzymes peroxiredoxin (Prx) I and II. We now show that PrxI associated with membranes is transiently phosphorylated on tyrosine-194 and thereby inactivated both in cells stimulated via growth factor or immune receptors in vitro and in those at the margin of healing cutaneous wounds in mice. The localized inactivation of PrxI allows for the transient accumulation of H.sub.2O.sub.2 around membranes, where signaling components are concentrated, while preventing the toxic accumulation of H.sub.2O.sub.2 elsewhere. In contrast, PrxII was inactivated not by phosphorylation but rather by hyperoxidation of its catalytic cysteine during sustained oxidative stress. Author Affiliation: (1) Division of Life and Pharmaceutical Sciences, Ewha Womans University, Seoul 120-750, Korea (2) Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon 305-333, Korea Article History: Received 24 July 2009; Revised 6 November 2009; Accepted 4 January 2010 Article Note: (miscellaneous) Published: February 18, 2010

The nanos-class gene of the leech Helobdella robusta (Hro-nos) is present as a maternal transcript whose levels decay during cleavage; HRO-NOS protein is more abundant in the D quadrant cells relative to the A, B, and C quadrants; and HRO-NOS is more abundant in the ectodermal precursor cell (DNOPQ) than in its sister mesodermal precursor (DM) (Pilon and Weisblat, 1997). Here, using in situ hybridization, we show that Hro-nos mRNA is broadly distributed throughout the zygote, is concentrated in both animal and vegetal teloplasm during stage I and is at higher levels in DNOPQ than in DM at stage 4b. Hro-nos expression increases after stage 7, as judged by in situ hybridization, developmental RT-PCR, and western blots; this increase must therefore represent later zygotic expression. Of particular interest, during stages 9 and 10, each of 11 mid-body segments (M8-M18) has a pair of Hro-nos positive 'spots' comprising of one or two large cells each. These spots later disappear in an anteroposterior progression. We find that these Hro-nos-expressing cells are of mesodermal origin, arising in a segmentally iterated manner from the M lineage, and correspond to cells previously proposed as primordial germ cells (PGCs; Burger, 1891; Weisblat and Shankland, 1985). These results support the proposal that nanos-class genes functioned in the specification of germline cells in the ancestral bilaterian and possibly in a separate process related to embryonic polarity in the ancestral protostome. Key Words: annelid; leech; Helobdella; germline; nanos.