Compensatory response to uninephrectomy in immature animals is stronger compared with that in adult ones and the response is due mainly to renal cell proliferation. The present study explored to show the growth pattern of the remaining kidney immediately after uninephrectomy in immature rats with special reference to proliferating activity and epidermal growth factor (EGF). Immunolocalizations of proliferating cell nuclear antigen (PCNA) and EGF in immature rat kidney were examined during the first three days after uninephrectomy. Semi-quantitative analysis of the expression of preproEGF mRNA was performed. One day after the operation, the PCNA positive cell ratios in the glomeruli and the proximal tubules were significantly higher in unilaterally nephrectomized (UNx) rats than in sham-operated (Sham) rats. In UNx and Sham rats, the proximal and distal tubular cells showed positive reactions to EGF antibody. The positive reaction of proximal tubules to EGF antibody was weaker in UNx than in Sham rats 1 day after the operation, while the degree of reactivity was not different between UNx and Sham rats 3 days after the operation. The level of expression of preproEGF mRNA in the kidney was significantly lower in UNx than in Sham rats 1 day after the operation. These results indicate that unilateral nephrectomy in immature rats causes increased proliferative activity and decreased expression of EGF in the remaining kidney during the early period of compensatory renal growth.

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This study describes the expression of CD44v6 in the bone development and is the first study of its kind to the authors' best knowledge. The CD44 family is a family of transmembrane glycoproteins that acts as cell adhesion molecules binding cells to other cells as well as cells to the extracellular matrix. It has been suggested that the CD44v6, a family member of CD44, is closely related to the osteosarcoma metastasis. In general, when cancer cells metastasize, they revert to their immature forms. In the present study, therefore, we have investigated CD44v6 and the standard form of CD44 (CD44st) in two types of immature forms of bone tissues: developmentally immature stages from fetuses to adults as well as experimentally immature stages using fracture models. CD44st expression was identified in osteoblasts, osteocytes, and in the peripheral portion of the bone matrix from the fetal to young ages of rats. Many more intense reactions for CD44v6 were observed in the bone matrix than CD44st in fetal stages. In experimental fracture models, positive immunoreactions to CD44st were clearly observed in the osteoblasts and osteocytes. CD44v6-positive immunoreactivity, however, was not detected in either osteoblasts or the bone matrix. In conclusion, CD44v6 is expressed in the embryonic stages and may be involved in the bone matrix formation as a matrix-associated ectodomain during normal ontogenetic development but not involved in the process of fracture healing.

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We observed gliosis with cell death in the rat amygdala 3 and 14 days after myocardial infarction (MI). Cresyl violet-positive neurons had condensed cytoplasm, and Fluoro-Jade B-positive cells were detected in the amygdala 14 days, not 3 days, after MI. Only a few glial fibrillary acidic protein (GFAP)-immunoreactive astrocytes and ionized calcium-binding adapter molecule 1 (Iba-1)-immunoreactive microglia showed activated form; hypertrophied cytoplasm, and highly ramified and retracted processes of astrocytes and microglia in the amygdala at 3 days after MI, respectively. At 14 days after MI, many astrocytes and most of microglia showed activated forms. These results suggest that MI may induce neuronal death and reactive gliosis in the amygdala.

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The jungle crow (Corvus macrorhynchos) distribution stretches from eastern Eurasia continent to southeastern Asia. The distribution of the black-billed magpie (Pica pica sericea) stretches from Korea and China to the Kyushu area in Japan. They are both in the Family, Corvidae, and have iridescent feather colors, but the iridescent feather color of the black-billed magpie is more remarkable than that of the jungle crow. We observed the feather microstructure of these birds using electron microscope. On the barbules surface, the barbules twist and prong between the jungle crow and black-billed magpie were not similar. In the barbules cross section, the black-billed magpie showed a complex structure of melanin granules, the jungle crow showed a simple structure of melanin granules.

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In the 3 years leading up to November 2009, 6 different types of naturally occurring neoplasms associated with avian leukosis virus subgroup J (ALV-J) were diagnosed by histopathology, polymerase chain reaction (PCR) and immunohistochemistry (IHC) in 140 layer hens out of approximately 100,000. The most prevalent tumor type was hemangioma (50%) in commercial layer flocks; the second most prevalent neoplasm type was myelocytoma (38.6%); a small number of ALV-J positive lymphomas (4.3%) that were not associated with Marek's disease (MD) or lymphoid leukosis (LL) was observed. Histiocytic sarcomas (2.1%) were found mainly in the spleen, liver and kidney. Fibrosarcomas (2.8%) presented as metastatic thigh, liver, lung and kidney neoplasms. Three cases of intestinal adenocarcinoma (2.1%) were found associated with ALV-J. Chickens with multiple tumors were a common phenomenon. Usually, hemangiomas plus myelocytomas (8.6%), myelocytomas plus histiocytic sarcomas (2.1%), hemangioma plus myelocytoma and lymphoma (3.6%) were found in various viscera organs. The present report describes the occurrence of multiple neoplasms associated with ALV-J in field layer hens.

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Adipocytes derived from different anatomical sites vary in the expression of adipocytokines and growth factor genes. Adipogenesis is tightly associated with angiogenesis, although the regional variation of angiogenic growth factor gene expression in adipose tissues remains unclear. In this experiment, we studied the fat depot-specific differences (subcutaneous, intramuscular, intermuscular, renal, and mesenteric) in the expression of angiogenic growth factor mRNA [vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), fibroblast growth factor-10 (FGF-10), hepatocyte growth factor (HGF), and leptin], as well as the relationship between angiogenic growth factor mRNA level and adipocyte size in bovine adipose tissues. Intermuscular, renal, and mesenteric adipose tissues expressed significantly higher VEGF, FGF-2, and leptin mRNA levels than did subcutaneous and intramuscular adipose tissues. Mesenteric adipose tissue also expressed higher FGF-10 mRNA levels than did subcutaneous and intramuscular adipose tissues. There was no significant difference in the expression of HGF mRNA among adipose tissue depots. A significant correlation existed between adipocyte size and VEGF, FGF-2, FGF-10, and leptin mRNA levels. These results indicate that fat depot-specific difference in angiogenic growth factor gene expression results from the difference in adipocyte size.

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Previously analyzed F₂ mice between KK/Ta and RR/Sgn strains were further investigated by defining appropriate permutation-derived threshold levels for significance and by searching pairwise gene interactions. In addition, a principal component analysis was conducted to extract a potential parameter that accounts for the joint occurrence of metabolic abnormalities. As a result, one significant interaction, containing novel QTL on chromosome 15, was identified for plasma total-cholesterol levels. For the principal component that potentially accounted for the joint occurrence of metabolic abnormalities, one significant QTL was identified on chromosome 12. This locus was not significant for any single trait. These complex genetic bases could not be disclosed as long as a separate trait was analyzed by traditional single QTL scans.

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An updated nation-wide epidemiological survey of feline immunodeficiency virus (FIV) infection was conducted in Japan. Blood samples were collected from 1,770 outdoor accessing cats from March to October 2008. Serologically, 410 cats (23.2%) were positive for anti-FIV antibody. Proviral DNA of the FIV env V3-V5 region isolated from 348 cases could be phylogenetically analyzed. The present study disclosed a geographic distribution of four subtypes (A, B, C and D) of FIV in Japan. Even though an FIV vaccine was introduced in Japan, we do not currently know whether this vaccine is effective against all strains of FIV in Japan or not. Therefore, close attention still has to be paid to epidemic and genotypic trends of FIV.

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In vivo Simian Immunodeficiency Virus (SIV) challenge of macaques demonstrated the earlier disappearance of CD4 and CD8 double-positive (DP) T cells than CD4 single-positive T cells, although its mechanism remains unclear. Here we found that peripheral DP T cells were readily induced to express CCR5, a secondary receptor for SIV, by in vitro stimulation with either concanavalin A or anti-CD3/CD28 monoclonal antibodies. Activated DP T cells were more vulnerable to SIV infection, indicating that the ability of DP T cells to readily express CCR5 after activation may hasten DP T cell death by SIV infection in vivo.

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An assay for detection of platelet surface-associated (PSA-) IgG, IgM and/or complement (C3) in dogs was modified by preparation of artificial positive control platelets. Flow cytometry of fluorescein isothiocyanate (FITC)-conjugated anti-dog IgG, anti-dog IgM and anti-dog C3 antibodies was used to detect the PSA proteins. IgM single, IgM/C3 double and IgG/IgM/C3 triple positive platelets were prepared. FITC-conjugated anti-IgG antibody bound strongly only to the triple positive platelets. Binding of FITC-conjugated anti-IgM or anti-C3 antibody to the double and triple positive platelets was specifically blocked by preincubation with the respective non-FITC-conjugated same-origin antibodies. These results confirm that FITC-conjugated antibodies specifically detect PSA proteins and that the control platelets prepared in this study are appropriate positive controls for detection of PSA proteins by flow cytometry.

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Recent studies have shown that many kinds of stem cells are beneficial for patients suffering with neurodegenerative diseases. We investigated the effects of neural stem cell (NSC), Maudsley hippocampal clone 36 (MHP36) in the Niemann-Pick disease type C (NP-C) model mice. Herein, we demonstrate that MHP36 transplantation improves the neuropathological features without acute immune response and promotes neuronal networks with functional synaptic transmission. The number of surviving Purkinje neurons substantially increased in MHP36 transplanted NP-C mice compared with sham-transplanted NP-C mice. MHP36 significantly reduced both of astrocytic and microglial activations. We also found that these surviving Purkinje neurons have normal functional synapses with parallel fibers that have normal glutamate release probability in MHP36 transplanted NP-C mice. Furthermore, real-time PCR analysis revealed up-regulation of genes involved in both excitatory and inhibitory neurotransmission encoding subunits of the ionotropic glutamate receptors GluR2, 3 and GABA_A receptor β2. These findings suggest that NSC, MHP36 transplantation may have therapeutic effects in the treatment of NP-C and other neurodegenerative diseases.

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Epidemiology of Eimeria species in poultry flocks is important to increase the effectiveness of vaccinations and prophylactic strategies on chicken farms. In this study, fecal samples from 356 chicken farms were collected randomly and examined for the prevalence of Eimeria species. Through microscopic examination, it was determined that 78.7% of the tested farms were positive in Eimeria-infection. Seven Eimeria species were detected in all the positive farms by PCR amplification of the internal transcribed spacer 1 (ITS-1) region with species-specific primers. E. acervulina and E. tenella were the most prevalent, followed by E. brunetti and E. praecox (87.5, 62.5, 59.3, and 37.5% of the farms, respectively). Each of E. maxima, E. mitis, and E. necatrix was identified in 31.3% of the farms. Individual positive fecal samples contained multiple Eimeria species (mean=3.4). Since E. maxima is known to generate antigenic variants, cross-immunity was investigated for four isolates of E. maxima from the poultry farms in different regions of Korea. The extent of cross-protection varied from 54.3 to 100% against the heterologous isolates. The results obtained from this large-scale survey will be a useful reference for controlling coccidiosis in the poultry industry.

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BALB/c mice were inoculated intracerebrally with fixed rabies virus (CVS-11) and pathomorphological changes in the central nervous system were studied. Infected mice showed ruffled hair, hunchback, anorexia, emaciation and ataxia at 5 days postinoculation (DPI), but paralysis did not occur. Viral antigens were first detected in the pyramidal cells of the cerebral cortex and hippocampus at 3 DPI, and these cells exhibited apoptosis at 5 DPI. Microglial cells and astroglial cells significantly increased in the areas of the nerve cells which showed apoptosis. However, spinal neurons and spinal dorsal root ganglion cells did not exhibit apoptosis despite virus infection. These observations indicate that different mechanism which causes apoptosis exists among the neurons of the brain and spinal cord, and glial cells play an important role in pathogenesis of the experimental rabies.

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A 10-year-old, castrated, mixed-breed dog presented with a 1.5-month history of scattered, crateriform ulcers on the trunk and extremities. Some skin lesions appeared to regress spontaneously, but new lesions developed. Thoracic radiography revealed pulmonary consolidated lesions suggestive of tumor. A skin biopsy was performed for histopathological, immunohistochemical and clonality analyses. Histopathological examination of the cutaneous lesion revealed an intense infiltration of atypical lymphoid cells with some other cell populations around the blood vessels in the dermis. Atypical lymphoid cells were shown to be CD3-positive in the immunohistochemical analysis. The presence of clonally expanded T-cells was revealed by the clonal rearrangement of T-cell receptor γ-chain gene. From the above findings, the dog was diagnosed with lymphomatoid granulomatosis.

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An 11-year-old, castrated male beagle dog was presented with a sudden onset of clinical signs of depression, abdominal discomfort, anorexia and melena. Radiography and ultrasonography revealed a well-circumscribed mass lesion with a size of 5 cm in diameter at the hypogastrium. A complete blood count and blood chemistry revealed severe anemia, hypoproteinemia and hypoalbuminemia. Through celiotomy, a large tumor mass involving the ileum was resected. The inside of the mass was irregular and sponge-like structure with multiple cavitated structures. On histology, the lesion was diagnosed to be hemangioma of the ileal wall. To the best of our knowledge, this unusual case is the first clinical report on the ileal hemangioma in non-human animal species.

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Fifteen 8-month-old fennec foxes imported from Sudan showed fever, mucopurulent ocular discharge, diarrhea, severe emaciation, seizures, and generalized ataxia, and died. Three of the 15 animals were presented for diagnostic investigation. Severe dehydration, brain congestion, and gastric ulcers were observed in all animals. In one animal, the lungs had failed to collapse and were multifocally dark red in appearance. Histopathologically, there were lymphohistiocytic meningoencephalitis with malacia, mild interstitial pneumonia, lymphoid depletion of lymphoid tissues and organs, and intestinal villous atrophy with intralesional coccidia. There were many intracytoplasmic and/or intranuclear inclusion bodies in the epithelial cells of the medullary velum, lungs, liver, kidneys, trachea, pancreas, stomach, gall bladder, urinary bladder, and ureters, and in macrophages of malacia foci and lymphocytes and macrophages of lymphoid organs. Additionally, intestinal coccidia were confirmed to be Isospora species by a fecal test. To our knowledge, this is the first report of canine distemper with intestinal coccidiosis in fennec fox.

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An 8-month-old, Nubian wether with a history of systemic illness was euthanatized for a pathological examination. At necropsy, the presence of disseminated abscessation and cellulitis in the limbs was noted. Other postmortem findings associated with the visceral disease in this animal included multiple abscess lesions, mainly in the lungs, kidneys, phalanxes and vertebrae. Histopathologically, lesions of arteriolitis were found as evidenced by bacterial embolisms in pulmonary and renal arteriola, indicating a bacteremia in the patient. Arcanobacterium pyogenes was consistently isolated from 8 lesions of abscessations, including the lesions of subcutaneous abscesses as well as bone marrow abscess in phalanxes and thoracic vertebrae. This is the first published report of disseminated arcanobacterial infection with bone marrow abscess of both the phalanxes and vertebrae in goat.

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The purpose of this study was to determine the pharmacokinetics and dose proportionality of mosapride citrate, a selective 5-HT₄ agonist, after oral administration in horses. Seven healthy Thoroughbreds were dosed with distilled water and 0.5, 1.0, or 1.5 mg/kg mosapride citrate through a nasogastric tube. Serum mosapride concentrations were measured by a liquid chromatography/tandem mass spectrometry (LC/MS/MS) method. Mosapride showed the C_maxs of 31, 60, and 104 ng/g and AUCs of 178, 357, and 566 ng·hr/g at doses of 0.5, 1.0, 1.5 mg/kg, respectively. The C_maxs and AUCs increased in proportion to the dose, indicating linear pharmacokinetics of mosapride up to 1.5 mg/kg. The pharmacokinetic profiles of mosapride in horses are quite different from that in humans. The average t_1/2 in horses was almost 2 fold longer than that reported in healthy adult humans. Therefore, it is thought that it is suitable to reduce the number of doses a day in horses compared to humans.

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Toltrazuril (TZR) is a triazine-based antiprotozoal agent. Following a single oral administration of TZR at 10 and 20 mg/kg to male pigs, the mean TZR concentration in plasma peaked at 4.24 and 8.18 μg/ml at 15.0 and 12.0 hr post-dose, respectively. TZR absorbed was rapidly converted to the short-lived intermediary metabolite toltrazuril sulfoxide (TZR-SO), and then metabolized to the reactive toltrazuril sulfone (TZR-SO₂). TZR-SO₂ was actually more slowly eliminated, with average half-lives of 231 and 245 hr, compared with TZR (48.7 and 68.9 hr) or TZR-SO (51.9 and 53.2 hr) in the 10 and 20 mg/kg groups, respectively. This study demonstrates that TZR metabolizes to TZR-SO₂ having a long-terminal half-life, enabling the persistent clinical efficacy in the treatment of I. suis infection. In contrast, special consideration should be given to the residual of TZR-SO₂.

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The three-dimensional distribution of dendrites from motoneurons innervating longissimus lumborum (Long Motoneurons) in the L4 spinal segment was examined in the adult cat using intracellular staining techniques. Long Motoneurons were electrophysiologically identified, stained with injection of biocytin and reconstructed from serial histological sections. Somas of Long Motoneurons were mainly located in the lateral-ventral area of the ventral horn. The dendritic distribution followed an orderly pattern in all motoneurons examined. Long Motoneurons showed a multi-directional distribution of dendrites, and the dendritic distribution pattern varied depending on the motoneuron. All studied motoneurons distributed dendrites from the spine into the white matter. The most significant morphological characteristic of the Long Motoneurons was the variation in their dendritic distribution. No relationship was observed between the effects of peripheral afferent inputs from the hindlimb and morphological characteristics of motoneurons.

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Bartonella vinsonii subsp. berkhoffii has been identified as an important pathogen in dogs and is an emerging pathogen in people with zoonotic potential. This study aimed to isolate Bartonella spp. in 250 blood samples collected from dogs in the province of Ankara, Turkey, between October 2006 and March 2007. The typing of the 23 isolates was carried out by PCR for citrate synthase (gltA) and the 16S-23S intergenic transcribed spacer (ITS). The prevalence of bacteremia was 9.2% in 250 samples. Among 170 shelter dogs, 21 (12.4%) were bacteremic for B. vinsonii subsp. berkhoffii, while the B. vinsonii subsp. berkhoffii bacteremia rate was 5% (2/40) for the stray dogs. B. vinsonii subsp. berkhoffii was not isolated from the pet dogs. The prevalence of bacteremia was found to be 25.5% (13/51) in shelter dogs aged less than one year old. All of the isolates were identified as B.vinsonii subsp. berkhoffii genotype III. In some isolates, MseI digest for gltA was found to be different from the American and European strains due to a single nucleotide change.

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To investigate the prevalence of antibodies to pathogenic Yersinia in breeding squirrel monkeys, the serum samples of 252 squirrel monkeys from 9 zoological gardens in Japan were tested by ELISA using plasmid-encoded Yersinia outer membrane protein (Yops) as the antigen. The cutoff value was calculated by using the serum samples of the squirrel monkeys from Suriname, where no prevalence of pathogenic Yersinia have been reported. According to the cutoff value, 164 of 252 (65.1%) squirrel monkeys were considered positive against pathogenic Yersinia. These positive monkeys belonged to 8 of the 9 zoological gardens, and the percentage of the seropositive monkeys ranged from 22.2 to 89.4%. Furthermore, in one zoological garden, the positive rate of the squirrel monkeys which were over 1 year old (95.7%) was significantly higher than those which were under 1 year old (23.3%). These results suggested that pathogenic Yersinia is highly prevalent among breeding monkeys in Japan.

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The causative agent of porcine reproductive and respiratory syndrome (PRRS) is PRRS virus (PRRSV), which belongs to the family Arteriviridae. GP5/M protein complex of PRRSV binds to sialoadhesion expressed on the cells to infect the cells. In this study, we developed a canine adenovirus type 2 (CAV-2) recombinant, termed rCAV2-GP5/M, expressing GP5 and M proteins. To evaluate the immunogenicity of the recombinant virus, mice were inoculated subcutaneously with rCAV2-GP5/M, and specific antibodies against PRRSV in the sera were measured by enzyme-linked immunosorbent assay and the viral neutralization test. Two weeks post-immunization (w.p.i.), anti-PRRSV antibodies were detected in the sera, slightly increased by booster immunization at four w.p.i., and then gradually decreased. The viral neutralizing test showed that neutralizing antibodies were present in the sera collected at two w.p.i., increased by booster immunization, and reached the maximum titer at six w.p.i. Lymphocyte proliferation responding to PRRSV antigens was also observed from two w.p.i. Although further studies are needed to evaluate the usefulness of the recombinant virus to protect pigs from PPRSV, we succeeded in developing a candidate vaccine against PPRSV infection by using CAV-2 vector.

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