Decrease in Hydraulic Conductivity of a Paddy Field using Biocalcification in situ

The hydraulic conductivity of a paddy field (Anthraquic Dystrustept), a silty clay soil containing more than 29% (w/w) of gravel, in Nagoya University Farm was reduced by in situ treatment of subsurface soil using bentonite and biocalcification (microbial calcium carbonate precipitation) through the addition of CaCl₂, urea, and corn steep liquor (CSL). The treatment decreased the hydraulic conductivity of the field from an average of 10^?3 cm/s to a range of 10^?5 to 10^?7 cm/s during 69 days, with reducing the proportion of pores of subsurface soil larger than 75 µm in diameter. The biocalcification effect was observed at 10-cm thickness from the treated subsurface. Laboratory soil core experiments demonstrated that the decrease in the hydraulic conductivity was not attributed to the effect of bentonite but mainly to the effect of biocalcification. The addition of CSL enhanced the urease activity of soil required for biocalcification, even at 4°C, as indicated by a decrease in urease activation energy temperature sensitivity. These experimental results agreed with the gradual decrease in hydraulic conductivity observed in the field when the average daily temperature was 7°C (days 24–69). It was suggested that the biocalcification is a potential technique to reduce the hydraulic conductivity of paddy field.     

Characterization of RyDEN (C19orf66) as an Interferon-Stimulated Cellular Inhibitor against Dengue Virus Replication

Dengue virus (DENV) is one of the most important arthropod-borne pathogens that cause life-threatening diseases in humans. However, no vaccine or specific antiviral is available for dengue. As seen in other RNA viruses, the innate immune system plays a key role in controlling DENV infection and disease outcome. Although the interferon (IFN) response, which is central to host protective immunity, has been reported to limit DENV replication, the molecular details of how DENV infection is modulated by IFN treatment are elusive. In this study, by employing a gain-of-function screen using a type I IFN-treated cell-derived cDNA library, we identified a previously uncharacterized gene, C19orf66, as an IFN-stimulated gene (ISG) that inhibits DENV replication, which we named Repressor of yield of DENV (RyDEN). Overexpression and gene knockdown experiments revealed that expression of RyDEN confers resistance to all serotypes of DENV in human cells. RyDEN expression also limited the replication of hepatitis C virus, Kunjin virus, Chikungunya virus, herpes simplex virus type 1, and human adenovirus. Importantly, RyDEN was considered to be a crucial effector molecule in the IFN-mediated anti-DENV response. When affinity purification-mass spectrometry analysis was performed, RyDEN was revealed to form a complex with cellular mRNA-binding proteins, poly(A)-binding protein cytoplasmic 1 (PABPC1), and La motif-related protein 1 (LARP1). Interestingly, PABPC1 and LARP1 were found to be positive modulators of DENV replication. Since RyDEN influenced intracellular events on DENV replication and, suppression of protein synthesis from DENV-based reporter construct RNA was also observed in RyDEN-expressing cells, our data suggest that RyDEN is likely to interfere with the translation of DENV via interaction with viral RNA and cellular mRNA-binding proteins, resulting in the inhibition of virus replication in infected cells.     

Facile and Selective Determination of Dipeptides Using 3-Methylcatechol as a Novel Fluorogenic Reagent

International Journal of Peptide Research and Therapeutics - Selective determination of peptides in mixtures or biological samples requires specific techniques for analysis. Herein, we report...     

Plasmodium Para-Aminobenzoate Synthesis and Salvage Resolve Avoidance of Folate Competition and Adaptation to Host Diet

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Facile synthesis of 1',2'-cis-beta-pyranosyladenine nucleosides

1',2'-cis-beta-Glycosyladenine nucleosides, such as beta-altroside, beta-mannoside, and beta-idoside, were efficiently synthesized from the corresponding 1',2'-trans-beta-6-chloropurine derivatives, beta-glucoside, and beta-galactoside. Nucleophilic substitution of the O-trifluoromethanesulfonyl groups at the C-2' and/or 3' was carried out using tetrabutylammonium acetate or cesium acetate under mild conditions. Subsequent deprotection and amidation afforded the desired compounds, 1',2'-cis-beta-pyranosyladenine nucleosides.     

Effects of cryopreservation methods on post-thaw motility of spermatozoa from the Japanese pearl oyster, Pinctada fucata martensii

In order to develop cryopreservation techniques for Japanese pearl oyster spermatozoa, the effects of various cryopreservation conditions on post-thaw motility were examined. Spermatozoa cryopreserved with 10% methanol (MET), dimethylformamide or dimethylacetamide plus 90% diluent comprising 80% seawater and 20% fetal bovine serum (FBS) showed higher percentages of post-thaw motility than those cryopreserved with 10% dimethylsulfoxide or glycerol. When spermatozoa were cryopreserved with various concentrations (0-20%) of MET and 100-80% diluent, 10% MET showed the highest percentages of post-thaw motility. When spermatozoa were cryopreserved with 10% MET and 90% diluent comprising various concentrations (0-100%) of FBS or Ringer solution mixed with seawater, the percentages of post-thaw motility peaked at 20% FBS or Ringer solution, and were significantly higher for 20% FBS than for 20% Ringer solution. The percentages of post-thaw motility increased with increasing dilution ratios from 2.5- to 50-fold. Spermatozoa cooled to -50 degrees C and then immersed in liquid nitrogen (LN) showed higher post-thaw motility than those cooled to -30 degrees C or -40 degrees C. When spermatozoa were cryopreserved to -50 degrees C at various cooling rates by changing the sample height above the LN surface, the post-thaw motilities of spermatozoa cooled at 10 cm (cooling rate: -21.3 degrees C/min) and 12.5 cm (-15.6 degrees C/min) from the LN surface were higher than those at 5, 7.5 or 15 cm. These results indicate that 10% MET plus 90% diluent comprising 80% seawater and 20% FBS is a suitable extender for cryopreservation of Japanese pearl oyster spermatozoa and that samples should be cooled to -50 degrees C at a cooling rate between -15 and -20 degrees C/min for efficient storage.     

Functional involvement of TMF/ARA160 in Rab6-dependent retrograde membrane traffic

The small GTPase Rab6 regulates retrograde membrane traffic from endosomes to the Golgi apparatus and from the Golgi to the endoplasmic reticulum (ER). We examined the role of a Rab6-binding protein, TMF/ARA160 (TATA element modulatory factor/androgen receptor-coactivator of 160 kDa), in this process. High-resolution immunofluorescence imaging revealed that TMF signal surrounded Rab6-positive Golgi structures and immunoelectron microscopy revealed that TMF is concentrated at the budding structures localized at the tips of cisternae. The knockdown of either TMF or Rab6 by RNA interference blocked retrograde transport of endocytosed Shiga toxin from early/recycling endosomes to the trans-Golgi network, causing missorting of the toxin to late endosomes/lysosomes. However, the TMF knockdown caused Rab6-dependent displacement of N-acetylgalactosaminyltransferase-2 (GalNAc-T2), but not beta1,4-galactosyltransferase (GalT), from the Golgi. Analyses using chimeric proteins, in which the cytoplasmic regions of GalNAc-T2 and GalT were exchanged, revealed that the cytoplasmic region of GalNAc-T2 plays a crucial role in its TMF-dependent Golgi retention. These observations suggest critical roles for TMF in two Rab6-dependent retrograde transport processes: one from endosomes to the Golgi and the other from the Golgi to the ER.     

Osteoactivin fragments produced by ectodomain shedding induce MMP-3 expression via ERK pathway in mouse NIH-3T3 fibroblasts

Intact osteoactivin, a novel type I membrane glycoprotein, were shed at a dibasic motif in the juxtamembrane region in C2C12 myoblasts. Extracellular fragments were secreted into the culture media by a putative metalloprotease. Extracellular fragments of osteoactivin, but not control protein, induced matrix metalloprotease-3 (MMP-3) expression in NIH-3T3 fibroblasts. Epidermal growth factor (ERK) kinase inhibitors inhibited the osteoactivin-mediated MMP-3 expression, whereas the extracellular fragment of osteoactivin activated ERK1/2 and p38 in the mitogen-activated protein kinase pathway. Our results suggest that the extracellular fragments of osteoactivin produced by shedding act as a growth factor to induce MMP-3 expression via the ERK pathway in fibroblasts.