Validation of the usefulness of 26S rDNA D1/D2, internal transcribed spacer, and intergenic spacer 1 for molecular epidemiological analysis of Macrorhabdus ornithogaster

Macrorhabdus ornithogaster (MO) is an infectious fungus that causes gastric damage in birds. In this study, we established nested and seminested polymerase chain reaction (PCR) methods that specifically amplify the domain D1/D2 region (D1/D2) of 26S ribosomal DNA (rDNA), internal transcribed spacer (ITS) of rDNA, and intergenic spacer (IGS) 1 region from avian feces. Phylogenetic analysis of MO collected from Japanese pet birds showed little genetic variation; analysis based on these regions did not distinguish between host species order, differences in MO shape, or host gastrointestinal symptoms. These regions were found to be unsuitable for molecular epidemiological studies of MO and further investigation into other genetic regions is required.     

Construction of an infectious full-length cDNA clone of Chrysanthemum virus B

An infectious full-length cDNA clone of Chrysanthemum virus B (CVB, genus Carlavirus), was constructed. Four cDNA fragments covering the whole genome of CVB-S were cloned between the Cauliflower mosaic virus 35S promoter and the nopaline synthase (NOS) terminator. Chrysanthemum and garland chrysanthemum were inoculated with the constructed plasmid, named pCVB, using a gene gun system. As is the case in wild-type, CVB-infected plants, no visible symptoms were observed on plants inoculated with pCVB; however, western blotting and electron microscopy indicated the presence of the progeny virus of pCVB. pCVB could be a useful tool for analyzing the functions of carlaviral proteins.     

Analysis of rice <Emphasis Type="Italic">RNA-dependent RNA polymerase 1</Emphasis> (<Emphasis Type="Italic">OsRDR1</Emphasis>) in virus-mediated RNA silencing after particle bombardment

RNA-dependent RNA polymerases (RDRs) play a key role in various RNA silencing pathways in many organisms. Using the nucleotide sequence of SGS2/SDE1/RDR6 in Arabidopsis as the search query for sequences that flank the insertions of rice retrotransposon Tos17, we selected rice mutant lines (OsRDR1). RT-PCR analysis showed that OsRDR1 mRNA was undetectable in leaves and calli of the mutants, while it was detected in wild type. RNA silencing was induced by particle bombardment to investigate any effects of OsRDR1 on RNA silencing with β-glucuronidase or green fluorescent protein DNA/RNA in the mutant lines. The results showed that RNA silencing was impaired in these mutant lines by inverted repeat (IR) DNA or in vitro transcribed double-stranded RNA. Further, the mutant lines were bombarded with Brome mosaic bromovirus (BMV, a ssRNA virus) or Wheat dwarf geminivirus (WDV, a ssDNA virus), each carrying the IR sequence of a reporter gene. As a result, RNA silencing was impaired by BMV. Interestingly, however, it was not impaired by WDV. Thus we propose that OsRDR1 is required for RNA silencing mediated by Bromovirus, but not by Geminivirus in this system.     

Adhesive Systems for Pesticide Delivery Through Plant Stems

An adhesive polymeric system for delivering pesticides through the stem of plants has been developed using a polymeric adhesive membrane with penetration enhancers. The active agent, imidacloprid, 1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine, incorporated in either acrylic adhesive polymer or natural rubber membrane was effectively absorbed through the stem of the model plant, eggplant (Solanum melongena), at a controlled rate of penetration. The penetration rate across the cuticular membrane was enhanced by 5·1 times and 2·4 times with l-menthol and d-limonene, respectively, incorporated in the polymer membrane as penetration enhancers. Correspondingly, the acrylic adhesive pesticide patch with l-menthol provided the highest insecticidal activity. The present adhesive transepidermal pesticide delivery system can deliver the active agent directly to the target site as well as minimizing the excess amount of the active agent wasted throughout the non-target environment. © 1997 SCI.     

Larval identification based on melanophore patterns in two Auxis species,bullet tuna Auxis rochei and frigate tuna Auxis thazard,from the northwest Pacific Ocean

Fisheries Science - Larvae of Auxis rochei and Auxis thazard are commonly found in tropical to temperate waters around the world; however, their identification is difficult due to their similar...     

Long-term survival in a dog with primary hepatic neuroendocrine tumor treated with toceranib phosphate

Primary hepatic neuroendocrine tumors (PHNETs) are rare in dogs, and limited information exists about the treatment of these tumors. A 12-year-old castrated male French bulldog was presented to our clinic with gastrointestinal signs. Diagnostic tests revealed increased hepatic enzyme levels, a mass in the hepatic quadrate lobe, multiple intrahepatic nodules, and enlarged hepatic hilar lymph nodes. The liver mass was diagnosed cytologically as a malignant epithelial tumor suspected to be of neuroendocrine origin. The dog was treated with single-agent toceranib phosphate (TOC) and survived 25.1 months after the initial presentation. On necropsy, a liver mass was found and was subsequently diagnosed as a PHNET on histopathology. To the best of our knowledge, this is the first report of long-term survival in a dog with PHNET treated with TOC.