Identification and characterization of Lisianthus necrotic ringspot virus,a novel distinct tospovirus species causing necrotic disease of lisianthus (Eustoma grandiflorum)

In 2007, lisianthus (Eustoma grandiflorum) plants with necrotic ringspots on the leaves were found in Kochi Prefecture, Japan. Tospovirus-like spherical enveloped particles with ca. 160 nm in diameter were observed with electron microscopy. The complete nucleotide sequence of the S RNA segment of the virus was determined, and phylogenetic analysis using deduced amino acid sequences of the nucleocapsid protein and the nonstructural S protein indicated that the virus is phylogenetically distinct from any known tospovirus species. The results suggest that the virus is a new member of the genus Tospovirus, in the family Bunyaviridae. The virus is the fifth distinct tospovirus occurring naturally in lisianthus in Japan. The necrotic symptoms were reproduced on lisianthus seedlings after mechanical inoculation. The host range of the virus isolate on several test plants was also examined.     

Influence of initial swimbladder inflation failure on survival of Pacific bluefin tuna,Thunnus orientalis (Temminck and Schlegel), larvae

This study investigated the influence of initial swimbladder inflation (ISI) failure on survival of Pacific bluefin tuna (PBT), Thunnus orientalis, larvae to prevent mass mortality due to sinking death. In Experiment 1, swimbladder inflation frequency and survival within an ISI promoted (PS) group, for which surface film of rearing water was removed, and a group without ISI promotion (NPS) were compared in 20 and 30 kL tanks. The PS group demonstrated significantly higher swimbladder inflation frequency and increased survival than the NPS group within 20 kL tanks at 9 days post hatching (dph). Similar tendencies were observed within 30 kL tanks. In Experiment 2, larval distribution and swimbladder inflation frequency in the night‐time were examined through larval sampling within the upper and middle layers of the water column and tank bottom within 1.6 and 30 kL tanks at 5 dph. Larvae at tank bottom had higher distributional density and significantly lower swimbladder inflation frequency than those distributed in the upper and middle layers within 1.6 kL tanks. Similar tendencies were observed within 30 kL tanks. Results of this study suggest the improvement of larval survival due to prevention of sinking death through ISI promotion in mass‐scale PBT larviculture.     

Peripheral lymphocyte subsets as a prognostic indicator of mortality and morbidity in healthy dogs

To evaluate the relationship among immune status and increased morbidity and mortality, peripheral blood lymphocytes (CD3(+), CD4(+), CD8(+) and CD21(+) cells) from 32 healthy dogs over 8 years of age were analyzed. Twenty-five of the 32 dogs were followed-up for 3 years after the analysis; and 14 dogs were found to be diseased, and nine dogs died. There was no notable difference between the ages of the dogs that died compared with the ones that survived. The relative percentage of CD4(+) and the CD4(+):CD8(+) ratio decreased notably in dogs falling ill compared with healthy dogs. The relative percentage of CD3(+) lymphocytes showed a notable decrease in dogs that died within 3 years in comparison with dogs that survived. In a discriminant analysis of morbidity and mortality, most patients were correctly classified as diseased or not and surviving or dead, respectively. These results indicate that the immunophenotypes of peripheral blood lymphocytes in older dogs offer promise as parameters for evaluating mortality and morbidity.     

Relationship between NF-κB expression and malignancy of canine mammary gland tumor tissues

In this study, the nuclear expression of nuclear factor kappa B (NF-κB) in 48 tissues specimens from 25 canine spontaneous mammary gland tumor (MGT) patients was assessed by immunohistochemistry to compare their levels with clinical features, histological types, prognostic outcomes and proliferative activities, including the mitotic index (MI) and cylcinD1 expression. Twelve of eighteen (66.7%) malignant tumor tissues showed greater than 10% nuclear staining, while benign tumor and hyperplastic tissues showed less than 10% nuclear staining. Higher nuclear expression of NF-κB was positively correlated with larger tumor size, lymph node metastasis and higher MI; however, no correlation was observed with distant metastasis and cyclin D1 expression. Higher NF-κB nuclear expression correlated with shorter patient survival. These findings suggest that NF-κB is a useful prognostic factor for canine MGT patients.     

Vaccine development against Neospora caninum infection

Neospora caninum is a recognized protozoan parasite of a wide range of mammalian hosts, and was reported for the first time in 1988. The isolation of its oocysts in dog's faeces in 1998 led to its establishment as a parasitic species undergoing typical coccidian life cycle. Infection with N. caninum causes paralysis and death in young livestock and companion animals, and is associated with abortions and stillbirth in cattle, and neurologic disease in calves. Considering the economic and agricultural importance of neosporosis, there is the urgent need to develop biological control measures aimed at preventing its transmission, infection, as well as reducing severity of the disease. In this paper, we have reviewed the progress made to date on the parasite-host immunology and on vaccine development including its prospects, and discussed possible strategies in the formulation of vaccine(s) against neosporosis.     

Studies on serological cross-reaction of Neospora caninum with Toxoplasma gondii and Hammondia heydorni

The enzyme-linked immunosorbent assay (ELISA) was used to examine cross-reactivity of Neospora caninum with Toxoplasma gondii and Hammondia heydorni. Anti-T. gondii mouse and cat sera cross-reacted with N. caninum soluble antigen (NLA), but not with the recombinant surface antigen (NcSRS2). Anti-H. heydorni dog sera showed no cross-reactivity with either the NLA antigen or the NcSRS2. Lack of cross-reactivity between anti-H. heydorni sera and N. caninum antigens, and the cross-reactivity of anti-T. gondii sera with the NLA suggest that N. caninum has common antigens to T. gondii except for NcSRS2 based on serology. In light of several studies suggesting a closer relationship between N. caninum and H. heydorni than with T gondii, examination of serological cross-reactivity with N. caninum may be necessary to further classify the parasites in addition to molecular and morphological studies and clarification of the life cycle.     

Neospora caninum NcSRS2 is a transmembrane protein that contains a glycosylphosphatidylinositol anchor in insect cells

We investigated the terminal location of NcSRS2, a surface antigen of Neospora caninum that has potential use for diagnosis, and demonstrated its importance as a vaccine component against neosporosis, in an insect-baculovirus expression system. To examine the role of the hydrophobic C-terminal tail in NcSRS2, four types of recombinant baculoviruses were constructed. Immunoblotting and N-terminal amino acid analysis revealed cleavage of a 6 kDa of the N-terminal signal peptide in the mature NcSRS2 protein. The recombinant NcSRS2 (rNcSRS2) lacking 25, and 62 amino acids from the termination codon were detected in supernatants from recombinant virus-infected cells, but not in recombinants with truncated 147 amino acids from the termination codon, and intact NcSRS2 gene (401 amino acids). By flow cytometric and confocal laser scanning microscopic analyses, the truncation of the hydrophobic C-terminal tail in NcSRS2 was shown to result in the reduction of protein expression on the cell surface relative to intact rNcSRS2. Except for the recombinant lacking the 147 C-terminal residues, three other rNcSRS2 were detected in the supernatants after treatment with phosphatidylinositol-specific phospholipase C. Our results demonstrate that the N. caninum NcSRS2 is a transmembrane protein that contains a glycosylphosphatidylinositol-anchor molecule in insect cells, and that the hydrophobic C-terminal domain is an essential component for GPI-membrane attachment. We have likewise shown the usefulness of the insect-recombinant baculovirus system in the expression of rNcSRS2.     

Sensory evaluation of carpet cleaner containing essential oil and the effect on mites

We prepared carpet cleaners containing three wood oils extracted from Thujopsis dolabrata Sieb. et Zucc. var. hondai Makino, Chamaecyparis obtusa Endl., and Chamaecyparis taiwanensis Masamune et Suzuki and studied their effects on mites and perfumerists' impressions. The oil concentrations were set at 0.1%, 0.2%, 0.4%, 0.8%, and 1.6%. The effects on Dermatophagoides pteronyssinus Trouessart were investigated. The sensory evaluations were conducted by seven male perfumerists using the SD method and they were asked to describe freely their impressions of the scents. These results showed that: (1) all three types of wood oil had a significant effect on making D. pteronyssinus inactive at 0.1% concentration; and (2) the wood oil of T. dolabrata evoked refreshing, natural, rich, and intellectual feelings; C. obtusa oil evoked vivacious, rich, and intellectual feelings; and C. taiwanensis evoked refreshing, natural, rich, rough, masculine feelings. According to the test subjects, T. dolabrata evoked woody and earthy impressions; C. obtusa evoked woody, citrus, and pine-resin impressions; and C. taiwanensis evoked woody, citrus, and medical impressions. Many issues remain to be investigated, but the inclusion of wood oil in carpet cleaners offered both good mite control and a pleasant aroma to humans. This study suggests a new potential for using these wood oils.     

Physiological and psychological responses to a heavy floor-impact sound generated by dropping an automobile tire in a wooden house

We investigated the physiological and psychological responses of ten healthy male volunteers to a single heavy floor-impact sound generated by dropping an automobile tire from heights of 50, 100, and 150cm in a wooden house. Blood pressure and peripheral blood flow were measured simultaneously, and sensory evaluation was conducted using the semantic differential method. The results obtained were as follows: (1) the systolic blood pressure increased and the peripheral blood flow decreased when the subjects heard the heavy floor-impact sound; (2) the heavy floor-impact sound caused the subjects to feel uncomfortable, but there was no significant change in sharp and monotonous feelings; and (3) for the heavy floor-impact sound for 100cm and that for 150cm, the subjects showed no difference in comfortable feeling, but we detected differences in the variations of both the systolic blood pressure and the peripheral blood flow.Part of this research was presented at the 48th Annual Meeting of the Japan Wood Research Society, Shizuoka, April 1998.     

Influence of wood wall panels on physiological and psychological responses

The effect of visual stimulation from wood on the body was examined in a comparative study using full-sized hinoki wall panels and a white steel wall panel. Continuous blood pressure measurements were used as the physiological indicator. Sensory evaluation by the semantic differential (SD) method and the profile of mood states (POMS) test were performed to determine changes in psychological impression. Results showed that visual stimulation from hinoki wall panels had an emotional and natural impression upon humans. Blood pressure decreased significantly in subjects who liked them, and there was no significant increase in blood pressure in subjects who disliked them. Visual stimulation from the white steel wall panel made an unhealthy and closed impression and increased the sense of depression. In addition, there was stress and a significant increase in blood pressure in subjects who disliked them. Consequently, visual stimulation from hinoki and white steel wall panels had different physiological and psychological effects. Results also showed that the same visual stimulation induced different physiological responses depending on the values of the individuals.Part of this paper was presented at the 48th Annual Meeting of the Japan Wood Research Society in Shizuoka, April 1998