Kazuhito Itamoto

Detection of Babesia canis rossi, B. canis vogeli, and Hepatozoon canis in dogs in a village of eastern Sudan by using a screening PCR and sequencing methodologies.

ABSTRACT Babesia and Hepatozoon infections of dogs in a village of eastern Sudan were analyzed by using a single PCR and sequencing. Among 78 dogs, 5 were infected with Babesia canis rossi and 2 others were infected with B. canis vogeli. Thirty-three dogs were positive for Hepatozoon. Hepatozoon canis was detected by sequence analysis.

Molecular Detection of a New Anaplasma Species Closely Related to Anaplasma phagocytophilum in Canine Blood from South Africa

ABSTRACT Canine DNA samples from South Africa were found to contain 16S rRNA gene nucleotide and citrate synthase gene nucleotide and deduced amino acid sequences that were most similar to Anaplasma phagocytophilum: 98%, 66%, and 69% similarity, respectively. This suggests that a new Anaplasma species closely related to A. phagocytophilum occurs in Africa.

Epidemiological Survey of Ehrlichia canis and Related Species Infection in Dogs in Eastern Sudan

Abstract:  The infection rates of Ehrlichia canis and related species in dogs in eastern Sudan were examined using molecular methods. Among 78 dogs examined, 63 (80.8%), 19 (24.4%), and 26 (33.3%) were positive for E. canis, Anaplasma platys, Mycoplasma haemocanis, and “Candidatus Mycoplasma haemoparvum,” respectively. Among these, 30 dogs were single‐positive: 25 for E. canis, 2 for A. platys, 1 for M. hemocanis, and 2 for “C. M. haemoparvum.” The rest of the dogs (48.7%) were positive for two or more pathogens.

Isolation of Aspergillus udagawae from a fatal case of feline orbital aspergillosis

Aspergillus fumigatus is the predominant etiological agent of sino‐orbital aspergillosis in humans and animals. Here we report for the first time A. udagawae, a previously recognised but rare opportunistic pathogen causing fatal orbital aspergillosis in a cat. Identification of this isolate was secured by comparative sequence based analyses of the ITS and the β tubulin region. Antifungal susceptibility testing results revealed that this isolate had high in vitro MIC to amphotericin B (AMB) that correlated with in vivo failure of therapy with AMB.

Clinical observations of Babesia gibsoni infection with low parasitaemia confirmed by PCR in dogs.

2004). In preliminary experiments, this PCR was able to detect approximately 10 B gibsoni-infected red blood cells in 1 μl of peripheral blood. All 35 animals with B gibsoni infection were positive by the PCR. To confirm the PCR findings, nucleotide sequences of randomly selected products of the B gibsoni-specific PCR were determined by direct sequence analysis, using the method described by Inokuma and others (2003). All the analysed sequences showed 100 per cent homology with B gibsoni Asia-1 (GenBank accession number AF175300). The animals with IMHA showed an acute onset of signs similar to those of B gibsoni infection, such as haemolytic and regenerative anaemia, icterus, anorexia or haematuria, at presentation. All eight animals with IMHA were found to be negative for B gibsoni infection by PCR. The information obtained for the 35 babesiosis cases and eight IHMA cases included histories and the findings of physical examination, complete blood counts, serum biochemical analysis and abdominal radiography. To compare the data from the dogs with low parasitaemia with the data from those with moderate to severe parasitaemia or with IMHA cases, chisquared tests and one-way analysis of variance were performed by using StatView v 5.0 (Hulinks). When the clinical and laboratory findings of the Babesia-infected animals showing low parasitaemia were compared with those of the dogs with moderate to severe parasitaemia, there were no significant differences between the two groups (Table 1). Although the numbers of dogs that showed icterus and the mean total bilirubin level in dogs with more severe parasitaemia were slightly higher than those of the dogs with low parasitaemia, the differences were not significant. Oxidative damage to erythrocytes induced by B gibsoni infection is thought to result in severe anaemia even in the presence of low parasitaemia (Otsuka and others 2002). Overall, the degree of parasitaemia in the B gibsoni-infected dogs did not relate to the clinical and laboratory findings. The clinical and laboratory findings in the dogs with B gibsoni infection with low parasitaemia were also compared with Clinical observations of Babesia gibsoni infection with low parasitaemia confirmed by PCR in dogs

Primary chondrosarcoma in the skull of a dog.

Chondrosarcoma of the skull is a rare primary malignant tumor that is slow-growing, but locally aggressive. A 5-year-old, golden retriever was presented to our hospital with a swelling in the left side of her head, and the swelling had slowly enlarged over the previous month. There were no significant changes on the neurological examination. A computed tomography scan revealed a large mass involving bone destruction and prominent matrix mineralization. T1-weighted magnetic resonance imaging showed a slightly low-signal intensity area and a T2-weighted image revealed marked, high-signal intensity. There was compression of the adjacent brain parenchyma. Histopathological examination confirmed the lesion to be a chondrosarcoma.

DNA methylation contributes toward silencing of antioncogenic microRNA-203 in human and canine melanoma cells.

Melanoma is a poor-prognosis cancer in both humans and dogs. We have elucidated the antitumor mechanisms of antioncogenic microRNA (miR)-203 which is downregulated in human melanoma, as well as in canine melanoma. The aim of this study was to clarify the mechanism of this downregulation. We focused on epigenetic aberration of miR-203 transcription. Treatment with 5-aza-2′-deoxycitidine (5-aza) markedly upregulated the expression level of miR-203 in almost all of the cell lines tested. Furthermore, bisulfite sequencing or methylation-specific PCR showed DNA methylation of CpG islands upstream of the miR-203 coding region (MIR203) in both human and canine melanoma cells, as well as in canine clinical specimens, but not in human normal melanocytes. The results of a luciferase activity assay showed obvious suppression of the transcription of miR-203 by DNA methylation. The use of the luciferase activity assay for CREB1 and an inhibition assay of miR-203 function performed with an miR-203 inhibitor confirmed the contribution of miR-203 upregulation toward the negative regulation of the target gene of miR-203. These results indicate that canine melanoma might be a preclinical model of human melanoma for epigenetic studies. In addition, this study suggests that agents that can demethylate MIR203 could be a common promising therapeutic agent for the treatment of human and canine melanomas.

Malignant mixed tumor in the salivary gland of a cat.

The presence of a malignant mixed tumor, also known as a carcinosarcoma, in the salivary gland is very rare. Such tumors, which are typically aggressive, are characterized by the presence of carcinomatous and sarcomatous components. A 9-year-old neutered female domestic short-haired cat presented with swelling in the right mandibular lesion that had rapidly enlarged over the previous 3 weeks. Physical examination revealed a large, fluctuated and painless subcutaneous swelling that was associated with a firm mass. Radiographs of the head revealed a soft-tissue density that involved faint circular calcific opacity. Contrast-enhanced computed tomography revealed that the peripheral capsulated cystic area had a contrast enhanced region without bone lysis. The cat received a total excision of the mass and postoperative radiotherapy. Histopathological analysis of the mass revealed that it was a malignant mixed tumor. Metastasis to the lung was discovered 7 weeks later, at which time treatment was stopped.

Application of ventriculoperitoneal shunt as a treatment for hydrocephalus in a dog with syringomyelia and Chiari I malformation

A twenty-month-old Chihuahua male dog was presented to us suffering with ataxia. Based on the physical examination, X-ray and magnetic resonance imaging (MRI) examinations, we diagnosed the dog with hydrocephalus, Chiari I malformation and syringomyelia. Treatment consisted of internal medical treatment and the placement of a ventriculoperitoneal (VP) shunt. The ventricular dilatation was relieved and the dog improved neurologically; however, the Chiari I malformation and syringomyelia remained after surgically positioning the VP shunt.

Enzyme-Linked Immunosorbent Assays Based on Neospora caninum Dense Granule Protein 7 and Profilin for Estimating the Stage of Neosporosis

ABSTRACT Neospora caninum is an intracellular protozoan parasite that causes bovine and canine neosporosis, characterized by fetal abortion and neonatal mortality and by neuromuscular paralysis, respectively. Although many diagnostic methods to detect parasite-specific antibodies or parasite DNA have been reported, to date no effective serodiagnostic techniques for estimating pathological status have been described. Our study aimed to elucidate the relationship between the parasite-specific antibody response, parasite activation, and neurological symptoms caused by N. caninum infection by using a recombinant antigen-based enzyme-linked immunosorbent assay. Among experimentally infected mice, anti-N. caninum profilin (NcPF) antibody was only detected in neurologically symptomatic animals. Parasite numbers within the brains of the symptomatic mice were significantly higher than those in asymptomatic animals. In addition, anti-NcPF and anti-NcGRA7 antibodies were mainly detected at the acute stage in experimentally infected dogs, while anti-NcSAG1 antibody was produced during both acute and chronic stages. Furthermore, among anti-NcSAG1 antibody-positive clinical dogs, the positive rates of anti-NcGRA7 and anti-NcPF antibodies in the neurologically symptomatic dogs were significantly higher than those in the non-neurologically symptomatic animals. Our results suggested that the levels of anti-NcGRA7 and anti-NcPF antibodies reflect parasite activation and neurological symptoms in dogs. In conclusion, antibodies against NcGRA7 and NcPF may have potential as suitable indicators for estimating the pathological status of neosporosis.