Pulmonary adenosquamous carcinoma in a dog

A mass that developed in the lung of a 10-year-old mixed-breed dog was pathologically examined. Histopathological examination showed papillary and tubular growth of glandular epithelium-like cells in some areas and growth of squamous cells arranged in nests in other areas, showing coexistence of adenocarcinoma and squamous cell carcinoma in a lung tumour. Immunohistochemical staining with anti-keratin-cytokeratin antibody was strongly positive for cytoplasms in both components. Electron microscopically, the neoplastic cells of the adenocarcinoma component had features of glandular cells, with microvilli, numerous free ribosomes, large round secretory granules and intercellular desmosomes. Non-keratinized squamous cells had tonofilaments and intercellular desmosomes. These findings led to the diagnosis of primary adenosquamous carcinoma, which demonstrates phenotypic profiles characteristic of both epidermal keratinocytes and glandular epithelium.     

Diagnosis of histoplasmosis by detection of the internal transcribed spacer region of fungal rRNA gene from a paraffin-embedded skin sample from a dog in Japan

The lesions of histoplasmosis in dogs in Japan differ from those in dogs in North America. Affected dogs in Japan have had multiple granulomatous or ulcerated foci in skin or gingiva and have not had pulmonary or gastrointestinal lesions. The present report introduces a polymerase chain reaction (PCR) diagnosis of canine histoplasmosis and the characteristic of disease in Japan. The surgically removed skin ulcerate samples from a 5-years-old female Shiba-inu native to Japan without traveling out of the country were evaluated. Tissue samples had many yeast-like organisms in the macrophages. DNA was extracted from paraffin-embedded tissue samples. A nested PCR technique was applied. The detected sequence of the internal transcribed spacer of ribosomal RNA gene had 99.7% in homology with Ajellomyces capsulatus (the teleomorph of Histoplasma capsulatum). Clinical manifestations, historical background of equine epizootic lymphangitis in Japan, and a human autochthonous case of histoplasmosis farciminosi indicated that this dog might have been infected with H. capsulatum var. farciminosum as a heteroecism.     

Sequence comparison of the dopamine receptor D4 exon III repetitive region in several species of the order Carnivora

It was previously demonstrated that the dog dopamine receptor D4 (DRD4) gene is polymorphic in terms of the repeat number and/or order of 39- and 12-bp sequences located in the third exon. To examine whether or not the repetitive region is present in other species of the order Carnivora, the homologous region of DRD4 genes were sequenced in the gray wolf, raccoon dog, Asiatic black bear, common raccoon and domestic cat. In the family Canidae, the wolf had an identical sequence to that of the dog 447b allele, and a repetitive sequence similar to the dog DRD4 was also recognized in the raccoon dog. On the other hand, no obvious repeated structure was observed in the sequences of the bear, raccoon and cat.     

Interspecies transmission of influenza viruses: H5N1 virus and a Hong Kong SAR perspective

This account takes stock of events and involvements, particularly on the avian side of the influenza H5N1 'bird flu' incident in Hong Kong SAR in 1997. It highlights the role of the chicken in the many live poultry markets as the source of the virus for humans. The slaughter of chicken and other poultry across the SAR seemingly averted an influenza pandemic. This perspective from Hong Kong SAR marks the coming-of-age of acceptance of the role of avian hosts as a source of pandemic human influenza viruses and offers the prospect of providing a good baseline for influenza pandemic preparedness in the future. Improved surveillance is the key. This is illustrated through the H9N2 virus which appears to have provided the 'replicating' genes for the H5N1 virus and which has since been isolated in the SAR from poultry, pigs and humans highlighting its propensity for interspecies transmission.     

Nuclear transfer in cattle : effect of linoleic acid-albumin on freezing sensitivity of enucleated oocytes

The effect of linoleic acid-albumin (LAA) supplementation to the media for IVM, enucleation, and activation on the developmental potential of bovine embryos produced by nuclear transfer (NT) into frozen-thawed cytoplasts was investigated. Blastomeres derived from morulae was placed in the perivitelline space of frozen-thawed cytoplasts, which were then fused by a DC pulse. The proportion of fused embryos was similar between groups with and without LAA (87 vs. 90%). The proportion of development to blastocysts of NT embryos derived from the media with LAA (14%) was higher than that without LAA (4%), indicating that LAA treatment of bovine oocytes during IVM, enucleation and activation can improve the ability of such cytoplasts after freezing and thawing to develop into blastocysts after NT.     

Effects of orvus ES paste on canine spermatozoal longevity after freezing and thawing

Because of weak resistance of canine sperm to freezing, an applicable method of preparing canine frozen semen has not yet been established. We added various concentrations of Orvus ES Paste (OEP) to egg yolk Tris-fructose citrate, and investigated its effectiveness on survival of spermatozoa. Addition of 0.5-1.0% OEP to the extender for freezing canine semen was effective in prolonging post-thaw survival of spermatozoa.     

Isolation of Theileria sergenti piroplasms from infected erythrocytes and development of an enzyme-linked immunosorbent assay for serodiagnosis of T sergenti infections

A method of obtaining a pure suspension of Theileria sergenti piroplasms from infected bovine erythrocytes was developed and the resulting parasites used as antigen in an enzyme-linked immunosorbent assay (ELISA). Piroplasms were freed from infected erythrocytes using the nitrogen cavitation technique and then separated from unbroken erythrocytes by centrifugation at 670 gmax. The parasites in the supernatant were then sedimented by centrifugation at 2700 gmax and the purified fraction examined by electron microscopy. This examination showed that the isolated piroplasms were morphologically intact and that there were few contaminants. SDS-PAGE and spectrophotometric analysis showed that this fraction contained little erythrocyte component. The piroplasms thus obtained were sonicated and treated with Triton X-100 then used for ELISA antigen. The ELISA values had a high correlation with titres obtained using the indirect fluorescent antibody test on sera from cattle infected with T sergenti.     

Enzyme-linked immunosorbent assay using solubilised antigen for detection of antibodies toAnaplasma marginale

An enzyme-linked immunosorbent assay (ELISA) was used to detect antibodies against Anaplasma marginale. A marginale bodies were separated from parasitised erythrocytes by a modified nitrogen decompression method, sonicated, then solubilised with Triton X-100 and used as the ELISA antigen. In this ELISA system the required amount of antigen protein was 16.2 ng for each well. In the course of experimental infections, of calves, significant antibody levels were detected by ELISA and the complement fixation test (CFT) at almost the same time. Antibodies against A. marginale were detectable for longer periods using the ELISA than using the CFT. Sera from calves infected with Babesia bigemina, B. bovis, B. ovata, Theileria sergenti and Eperythrozoon wenyoni gave no reaction; however, antisera against A. centrale did react with the A. marginale ELISA antigen.     

Decrease in erythrocyte survival in Theileria sergenti-infected calves determined by non-radioactive chromium labelling method.

Pathogenesis of anemia in the calves infected with Theileria sergenti was investigated from the viewpoint of erythrocyte survival decrease in the circulating blood. For investigation of erythrocyte survival a method of erythrocyte labelling with non-radioactive chromium (50Cr) was utilized. It was found that (1) the erythrocyte survival decreased markedly in the T. sergenti-infected calves compared with that in the uninfected calves; the survival rate of 25.7% for infected calves and 86.0% for uninfected ones on the fourth day after re-introduction of the labelled erythrocytes into the original donors, and that (2) the survival of non-parasitized erythrocytes in the infected calves was also decreased, which indicates no obvious relationship between parasitism and decrease in survival of erythrocytes.