Analysis of head and chest movements that correspond to gaze directions during walking.

In this paper, we analyze the relationship between head and chest movements and gaze direction in both walking and non-walking conditions. In a different approach from existing studies, we aim to analyze behavior when humans intentionally gaze at a certain target from two perspectives: (1) the relationship between gaze and body movements and (2) the effects of walking on body motion. We performed three experiments: fixed target scenes (Experiment 1), moving target scenes (Experiment 2) and more realistic gazing scenes (Experiment 3). The experimental results showed a linear relationship between the head and chest directions and gaze directions regardless of walking, non-walking situations, or target movements, and stronger gaze-head correlations than gaze-chest correlations. Further, we found effects of walking that constrained rotational body movements, and that body parts with larger moments were easily affected by walking. These results suggest that the findings of existing studies in non-walking situations may be applicable to walking situations directly or with simple modifications.

Effect of High Pressure Processing on a Wide Variety of Human Noroviruses Naturally Present in Aqua-Cultured Japanese Oysters.

The contamination of oysters with human norovirus (HuNoV) poses a human health risk, as oysters are often consumed raw. In this study, the effect of high pressure processing (HPP) on a wide variety of HuNoVs naturally present in aqua-cultured Japanese oysters was determined through a polymerase chain reaction-based method with enzymatic pretreatment, to distinguish between infectious HuNoV. Among five batches, genogroup I. genotype 1 (GI.1), GI.2, GI.3, and GI.8 HuNoV were detected from only one oyster not treated with HPP in the fifth batch, while genogroup II. genotype 1 to 4 (GII.1 to 4), GII.6, GII.8., GII.9, GII.13, GII.16, GII.17, and GII.22 HuNoV were detected from oysters not treated with HPP in all tested batches as determined by next-generation sequencing analysis. Neither GI nor GII HuNoV was detected in the oysters of any of the batches after HPP treatment. To our knowledge, this is the first study to investigate the effect of HPP on a wide variety of HuNoVs naturally present in aqua-cultured oysters.

Next-Generation Sequencing Analysis of the Diversity of Human Noroviruses in Japanese Oysters.

To obtain detailed information on the diversity of infectious norovirus in oysters (Crossostrea gigas), oysters obtained from fish producers at six different sites (sites A, B, C, D, E, and F) in Japan were analyzed once a month during the period spanning October 2015-February 2016. To avoid false-positive polymerase chain reaction (PCR) results derived from noninfectious virus particles, samples were pretreated with RNase before reverse transcription-PCR (RT-PCR). RT-PCR products were subjected to next-generation sequencing to identify norovirus genotypes in oysters. As a result, all GI genotypes were detected in the investigational period. The detection rate and proportion of norovirus GI genotypes differed depending on the sampling site and month. GII.3, GII.4, GII.13, GII.16, and GII.17 were detected in this study. Both the detection rate and proportion of norovirus GII genotypes differed depending on the sampling site and month. In total, the detection rate and proportion of GII.3 were highest from October to December among all detected genotypes. In January, the detection rates of GII.4 and GII.17 reached the same level as that of GII.3. The proportion of GII.17 was relatively lower from October to December, whereas it was the highest in January. To our knowledge, this is the first investigation on noroviruses in oysters in Japan, based on a method that can distinguish their infectivity.

Application of next-generation sequencing to investigation of norovirus diversity in shellfish collected from two coastal sites in Japan from 2013 to 2014.

A better understanding of the role played by shellfish regarding the manner of pathogen contamination, persistence, and selection may help considering epidemiology of noroviruses. Thus, norovirus genotype profiles in shellfish (Crassostrea gigas and Mitilus galloprovincialis) were investigated by using Next-generation sequencing (NGS) technology. In genogroup I (GI), 7 genotypes (abbreviated as GI.2 to GI.7, and GI.9) were detected from C. gigas, whereas 9 genotypes (GI.1 to GI.9) were detected from M. galloprovincialis. The genotype with the highest proportion found in both C. gigas and M. galloprovincialis was GI.4, and the second highest was GI.3. In genogroup II (GII), 17 genotypes (GII.1 to GII.9, GII.11 to GII.17, GII.21 and GI.22) were detected from C. gigas, whereas 16 genotypes (GII.1 to GII.8, GII.11 to GII.17, GII.21 and GI.22) were detected from M. galloprovincialis. The genotype with the highest proportion in both C. gigas and M. galloprovincialis was GII.4, the next highest differed between C. gigas and M. galloprovincialis. To our knowledge, this study may be the first trial to utilize the latest technology in this field, and reveal the diversity of norovirus genotypes present in shellfish.

Application of Next-Generation Sequencing to Evaluate the Profile of Noroviruses in Pre- and Post-Depurated Oysters.

The development of procedures for the efficient removal or inactivation of noroviruses from contaminated oysters is of great interest in oyster production. However, there is a critical limitation for evaluating the depuration efficacy of presently available procedures, as no suitable cell culture system currently exists to cultivate noroviruses. Thus, we applied a next-generation sequencing (NGS) technique to characterize norovirus genotypes in pre- and post-depurated oysters. As a result, we revealed the diversity of noroviruses in pre- and post-depurated oysters. Although the applied depuration procedure could reduce the number of bacterial agents to the level recommended by the Japanese Ministry of Health, Labour and Welfare, no significant changes were observed in the detection rate and the proportion of norovirus group (G) I and GII genotypes. To our knowledge, this is the first report to evaluate the profile of noroviruses in pre- and post-depurated oysters, specifically with respect to norovirus removal, using NGS; the findings imply that the removal of noroviruses from oysters through depuration is not presently sufficient. Further studies are needed to develop a more suitable depuration procedure for removing and/or inactivating noroviruses from contaminated oysters.

Analysis of transcriptional activities of the Meq proteins present in highly virulent Marek's disease virus strains, RB1B and Md5.

Marek's disease virus (MDV) is an oncogenic herpesvirus that causes malignant lymphomas in chickens. Recent field isolates of MDV have tended to exhibit increasing virulence, and MDV strains are currently classified into four categories based on their relative virulence. Meq, a putative MDV oncoprotein, resembles the Jun/Fos family of basic leucine zipper (bZIP) transcription factors and can regulate the expression of viral and cellular genes as a homodimer or as a heterodimer with a variety of bZIP family proteins. MDV isolates display distinct diversity and point mutations in Meq, which may contribute to changes in the transcriptional activities of Meq and subsequently, to observed increases in MDV oncogenicity. In this study, we introduced mutations into the meq gene and used dual luciferase reporter assays to analyze the transcriptional activities of the resulting Meq proteins to determine whether distinct mutations in Meq could be responsible for differences in transcriptional activity among MDV strains. A proline-to-alanine substitution at position 217, the second position of one of the proline direct repeats in the transactivation domain, enhanced the transactivation activity of Meq. In addition, we found that two substitutions at positions 283 and 320 affected transactivation activity. These results suggest that the distinct diversity of and point mutations in the Meq proteins are responsible for differences in transactivation activity among MDV strains.

Serological survey of Toxoplasma gondii in wild waterfowl in Chukotka, Kamchatka, Russia and Hokkaido, Japan.

Antibodies to Toxoplasma gondii were assayed by ELISA in 22 experimentally inoculated domestic ducks. In addition, a serological assay was carried out at Obihiro, Hokkaido, Japan, in 2004 and 2005, on 221 wild ducks of 5 species: Anas platyrhynchus (n = 111); A. poecilorhyncha (n = 27); A. acuta (n = 58); A. penelope (n = 16); and A. crecca (n = 9). Assays were also conducted using sera from 197 wild geese of 2 species, i.e., Anser albifrons (n = 162) and Ans. fabalis (n = 35). Birds were collected between 2003 and 2005 from 3 different areas: Lake Miyajima-numa, Hokkaido, Japan, regions around Anadyr city of Chukotka autonomous okrug, and Lake Makobetukoe, Kamchatka oblast, Russia. The ELISA cutoff value (OD) was > or =0.395 based on results from uninfected ducks; the final dilution ratio recognized as positive was represented by the end titer. The end titer in the experimentally infected ducks ranged from 1:400 to 1:3,200. Antibodies to T. gondii were found in 49 of the 221 wild duck samples from Japan: A. platyrhynchus (22/74); A. poecilorhyncha (2/15); A. penelope (3/16); A. acuta (4/58); and A. crecca (0/9), all in 2004. In 2005, T. gondii was found in A. platyrhynchus (13/37); and A. poecilorhyncha (5/12). Thirty-two of 197 wild goose samples were seropositive, i.e., Ans. albifrons (7/51) in 2004 and (11/72) in 2005 in Miyajima-numa, Japan and 9/39 in Chukotka, Russia as well as in Ans. fabalis (5/35) in Kamchatka, for which the end titer ranged from 1:100 to 1:3,200. In immunoblotting, the A. platyrhynchus samples showed specific IgG antibody binding to several antigens in the T. gondii lane, i.e., at 30 and 43 kDa, but not in the Neospora caninum lane. No specific bands were noted in samples for which antibody activity was not detected. These results suggest that wild waterfowl inhabiting Hokkaido, Chukotka, and Kamchatka may be exposed to T. gondii.

Identification and characterization of a novel spliced form of the meq transcript in lymphoblastoid cell lines derived from Marek's disease tumours.

In tumour cell lines established from Marek's disease (MD) lymphomas L-meq is consistently expressed. It contains a 180 bp insertion encoding additional copies of the proline-rich repeat in the meq open reading frame and its product may contribute to the maintenance of MD virus (MDV) latency. In this study, we identified a novel spliced form of the meq transcript in MD-derived lymphoblastoid cell lines and in MDV-infected cells. This transcript, termed Deltameq, encodes an N-terminal 98 aa of the Meq protein and lacks part of the basic leucine zipper (bZIP) and transactivation domains. In MD cell lines, transcription of L-meq was significantly downregulated, while that of the Deltameq transcript was upregulated during apoptosis. These observations were also confirmed at the protein expression level. Reporter assays using meq- and interleukin-2 (IL-2)-promoter-driven luciferase vectors revealed that DeltaMeq suppressed transactivation by L-Meq or Meq in a dose-dependent manner. Immunoprecipitation confirmed that DeltaMeq was associated with L-Meq or Meq physically. These results suggest that DeltaMeq could be involved in apoptosis in MD cell lines as it works as a negative regulator of L-Meq and Meq by direct interaction.