First report of blueberry red ringspot disease caused by <Emphasis Type="Italic">Blueberry</Emphasis><Emphasis Type="Italic">red</Emphasis><Emphasis Type="Italic">ringspot</Emphasis><Emphasis Type="Italic">virus</Emphasis> in Japan

Virus-like symptoms—red ringspots on stems and leaves, circular blotches or pale spots on fruit—were found on commercial highbush blueberry (Vaccinium corymbosum) cultivars Blueray, Weymouth, Duke and Sierra in Japan. In PCR testing, single DNA fragments were amplified from total nucleic acid samples of the diseased blueberry bushes using primers specific to Blueberry red ringspot virus (BRRV). Sequencing analysis of the amplified products revealed 95.7–97.7% nucleotide sequence identity with the BRRV genome. This paper is the first report of blueberry red ringspot disease caused by BRRV in Japan. The nucleotide sequence data reported in this paper are available in the GenBank/EMBL/DDBJ database as accessions AB469884 to AB469893 for BRRV isolates from Japan.     

Detection of Tobamoviruses from Soils by Non-precoated Indirect ELISA

A method for detecting tobamoviruses from field soils was developed using non-precoated indirect enzyme-linked immunosorbent assay (Id-ELISA). Absorbance values in Id-ELISA were relatively low after directly applying Pepper mild mottle virus (PMMoV)-infested soil extract. However, heat treating the soil extract before application greatly enhanced the absorbance values. The heat treatment was essential for the Id-ELISA detection of tobamoviruses from infested soil, although the efficiency of virus recovery varied depending on the properties of soil. The number of local lesions in the infectivity assay was consistent with the absorbance values in Id-ELISA. Moreover, the absorbance values in Id-ELISA were correlated with the incidence of soil transmission of PMMoV. Thus, Id-ELISA combined with heat treatment is a practical technique for the diagnosis of infestation with Tobamovirus in field soils, Gray Lowland soil and Sand-dune Regosol. Received 4 October 1999/ Accepted in revised form 9 December 1999     

Pathogenesis-related gene expression in rice is correlated with developmentally controlled Xa21-mediated resistance against Xanthomonas oryzae pv. oryzae

Disease resistance mediated by the resistance gene Xa21 is developmentally controlled in rice. We examined the relationship between Pathogenesis Related (PR) defense gene expression and Xa21-mediated developmental disease resistance induced by Xanthomonas oryzae pv. oryzae (Xoo). OsPR1a, OsPR1b, and OsPR1c genes were cloned and their induction was analyzed, in addition to the OsPR10a gene, at the juvenile and adult stages in response to a wildtype Xoo strain that induces a resistance response (incompatible interaction) and an isogenic mutant Xoo strain that does not (compatible interaction). We found that the adult stage leaves are more competent to express these OsPR1 genes and that the Xa21 locus is required for the highest levels of induction.     

Intranasal inoculation of chickens with encapsulated or nonencapsulated variants of Haemophilus paragallinarum: electron microscopic evaluation of the nasal mucosa

Chickens were inoculated intranasally with encapsulated or nonencapsulated strains of Haemophilus paragallinarum. The nasal mucosa of the chickens were examined, using scanning and transmission electron microscopy. In chickens given the encapsulated variant, marked loss of cilia and microvilli, infiltration of leukocytes, and deposition of a mucopurulent substance were seen on the surface of the nasal mucosa; the number of microvillous cells were markedly increased, and infiltration of mast cells into the lamina propria of the mucous membrane was observed. Numerous encapsulated organisms were found near cilia and on microvillous cells, and the capsule surrounding the organisms appeared to mediate attachment of the organisms to the cilia. In contrast, the nasal mucosa of the chickens given the nonencapsulated variants changed little morphologically. A few nonencapsulated organisms were found near cilia. Colonization of the nasal mucosa by encapsulated organisms probably was essential to induce the morphologic changes seen in the nasal mucosa.     

Assessment of predictive molecular variables in feline oral squamous cell carcinoma treated with stereotactic radiation therapy

This study evaluated molecular characteristics that are potentially prognostic in cats with oral squamous cell carcinoma (SCC) that underwent stereotactic radiation therapy (SRT). Survival time (ST) and progression‐free interval (PFI) were correlated with mitotic index, histopathological grades, Ki67 and epidermal growth factor receptor expressions, tumour microvascular density (MVD), and tumour oxygen tension (pO₂). Median ST and PFI were 106 and 87 days, respectively (n = 20). Overall response rate was 38.5% with rapid improvement of clinical symptoms in many cases. Patients with higher MVD or more keratinized SCC had significantly shorter ST or PFI than patients with lower MVD or less keratinized SCC (P = 0.041 and 0.049, respectively). Females had significantly longer PFI and ST than males (P ≤ 0.016). Acute toxicities were minimal. However, treatment‐related complications such as fractured mandible impacted quality of life. In conclusion, SRT alone should be considered as a palliative treatment. MVD and degree of keratinization may be useful prognostic markers.     

Predicting clinical outcome in feline oral squamous cell carcinoma: tumour initiating cells,telomeres and telomerase

Feline oral squamous cell carcinoma (SCC) has very poor prognosis. Here, a retrospective pilot study was conducted on 20 feline oral SCC patients who underwent stereotactic radiation therapy (SRT), to evaluate: (1) the value of putative tumour initiating cell (TIC) markers of human head and neck SCC (CD44, Bmi‐1); (2) telomere length (TL) specifically in putative TICs; and (3) tumour relative telomerase activity (TA). Significant inverse correlations were found between treatment outcomes and Bmi‐1 expression, supporting the predictive value of Bmi‐1 as a negative prognostic indicator. While TL exhibited a wide range of variability, particularly in very short fractions, many tumours possessed high levels of TA, which correlated with high levels of Bmi‐1, Ki67 and EGFR. Taken together, our results imply that Bmi‐1 and telomerase may represent novel therapeutic targets in feline oral SCC, as their inhibition – in combination with SRT – would be expected to have beneficial treatment outcome.