The dendritic cell (DC) network is a specialized system for presenting antigen to naive or quiescent T cells, and consequently plays a central role in the induction of T cell and B cell immunity in vivo. Despite considerable achievements in the last ten years, in our understanding of how DC induce and regulate immune responses, much remains to be learned about this complex system of cells. The history and current status of DC termed "directors of the immune system orchestra" is reviewed. The present understanding of DC cell biology, function and use, taking into account their complexity is discussed.

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Chlamydophila felis (C. felis), feline herpesvirus-1 (FHV-1) and feline calicivirus (FCV) were detected in 39 (59.1%), 11 (16.7%) and 14 (21.2%) cats respectively, from 66 domestic cats presented with conjunctivitis and upper respiratory tract disease (URTD) in 9 prefectures of Japan. Dual and multiple infections were found in 7 (10.6%) cats with both C. felis and FHV-1, 10 (15.2%) cats with both C. felis and FCV, and 1 (1.5%) cat with all three agents. C. felis was isolated from 11 (28.2%) of 39 PCR positive cats. Antigenic difference was found in a 96 kDa protein of our isolates and Fe/145 strain isolated in USA. In conclusion, C. felis is the most common agent of feline conjunctivitis and URTD, and the coinfection with C. felis, FHV-1 and FCV are also common in cats in Japan.

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Staphylococcus intermedius from pigeons, dogs, foxes, mink, and horses, was characterized by pulsed-field gel electrophoresis (PFGE) to evaluate the use of this typing method for discriminating among strains. SmaI cut the chromosomal DNA into 7-13 fragments ranging from approximately 48 kb to 655 kb, with most of the detectable fragments being smaller than 172 kb. S. intermedius from various animals had a high degree of restriction fragment length polymorphism. Pigeon strains have a similar genotype, despite the difference in their isolation area. Phage typing indicated that the dog, fox, and mink strains belong to the canine I or canine II type. The PFGE method further differentiated the mink strains from the dog and fox strains with regard to three fragments between 256 kb and 570 kb. As such, genomic DNA fingerprinting by PFGE appears to be an effective technique for discriminating S. intermedius strains from various animals. A combination of PFGE typing and phage typing would provide more detailed information than the single method for ecological investigations of S. intermedius.

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From April 1999 to December 2000, a survey was made on the distribution of Staphylococcus species on the skin of 7 kinds of animals and humans. Staphylococci were isolated from 12 (100%) of 12 pigs, 17 (89.5%) of 19 horses, 30 (100%) of 30 cows, 73 (90.1%) of 81 chickens, 10 (40%) of 25 dogs, 23 (76.7%) of 30 laboratory mice, 20 (52.6%) of 38 pigeons, and 80 (88.9%) of 90 human beings. The predominant staphylococci isolated from a variety of animal species were novobiocin-resistant species, S. xylosus and S. sciuri regardless of the animal host species. The novobiocin-resistant species including S. xylosus and S. sciuri were only occasionally isolated from human skin. The predominant staphylococci found on human skin were novobiocin-sensitive species, S. epidermidis (63.8%), followed by S. warneri (28.8%) and S. hominis (13.8%). The results suggest that the staphylococcal flora inhabiting animal skin are different from those of human skin in regard to the predominant species isolated. In this study, we used pulsed-field gel electrophoresis to examine the chromosomal polymorphisms of S. epidermidis isolated most frequently from human skin. Strains of S. epidermidis showed the greatest genomic diversity in their fragment patterns.

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The 16S-23S rRNA intergenic spacer regions (ISRs) of Fusobacterium necrophorum subsp. necrophorum and F. necrophorum subsp. funduliforme were characterized. Products of two sizes, about 360 bp (small) and 530 bp (large), were generated by PCR amplification from the 16S-23S rRNA ISR of all the strains tested. The large and small 16S-23S rRNA ISRs of F. necrophorum exhibited a level of sequence similarity of 93.9% to 99.7% and 94.2% to 98.6% homologies within the species, respectively. Only the large spacer regions in these bacteria contained one or two tRNA genes. F. necrophorum subsp. necrophorum contains the isoleucine and alanine tRNA gene, whereas F. necrophorum subsp. funduliforme contains the isoleucine tRNA gene.

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The 16S-23S rRNA intergenic spacer regions (ISRs) of five strains of "Fusobacterium pseudonecrophorum" which had been proposed as a new species, were compared with those of F. varium ATCC 8501^T. All the strains of "F. pseudonecrophorum" exhibited of sequence similarities of 97.7% to 100% to the strain of F. varium in their 16S-23S rRNA ISR sequences. This indicates that the strains of "F. pseudonecrophorum" and the type strain of F. varium are identical at the species level.

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To estimate the maternal effects of dog breeds using mitochondrial DNA(mtDNA) haplotypes in the dogs with several clinical disorders, 600 base pairs of mtDNA D-loop region were amplified from 365 dogs and were determined for mtDNA sequences. The diversity of the 600-bp sequences was classified into 64 haplotypes, including 46 newly discovered haplotypes, and the haplotypes were grouped into four clusters I to IV. Lineage analysis using the mtDNA haplotype indicated that each dog breed genetically comprises one or a few mtDNA haplotypes. When the relationship between genetic background and occurrences of clinical diseases was estimated, canine lineage analysis using mtDNA haplotype revealed that the disorders distributed in the dominant mtDNA haplotypes of each dog breed, but no disorder closely associated with mtDNA haplotypes was detected.

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The role of macrophages in the erythrocyte membrane oxidative damage and the pathogenesis of anemia in Babesia gibsoni-infected dogs with low parasitemia were investigated. Macrophages derived from peripheral blood monocytes (PBM) from B. gibsoni-infected dogs produced significantly higher chemiluminescent responses, indicating the release of reactive oxygen intermediates, than those from non-infected dogs when the cells were subjected to non-specific stimulation with phorbol 12-myristate 13-acetate (PMA) and opsonized zymosan (OZ), or infected dog erythrocyte membranes opsonized with infected dog serum. These results indicate that PBM of B. gibsoni-infected dogs with low parasitemia were highly activated compared to those of non-infected dogs. Furthermore, the membrane lipid peroxidation of normal dog erythrocytes incubated with PBM from B. gibsoni-infected dogs was significantly higher (p<0.05) than that of erythrocytes incubated with PBM from non-infected dogs when the PBM were stimulated with the opsonized membranes. These results suggest that the oxidative damage of erythrocytes observed in B. gibsoni-infected dogs with low parasitemia might be induced, in part, by reactive oxygen species released from the activated PBM. On the other hand, the present study also showed a significant increase (p<0.001) of IgG-bound erythrocytes in B. gibsoni-infected dogs compared with such erythrocytes in non-infected dogs. The increase of IgG-bound erythrocytes in infected dogs might reflect the increase of erythrocytes with oxidative damage induced by the infection with B. gibsoni. The results of the present study suggest that the increase of IgG-bound erythrocytes in the circulation of infected dogs induce a high degree of erythrocyte loss via immunological phagocytosis by activated macrophages, resulting in severe anemia in spite of low parasitemia.

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The effect of heat treatment was examined against oocysts of Cryptosporidium parvum, Cryptosporidium muris and chicken Cryptosporidium sp. isolated in Japan. The oocysts of these species were exposed at 50, 55, 60 and 70°C for 5, 15, 30 and 60 sec in water bath, respectively. To determine the infectivity of heated oocysts, the mice and chickens were inoculated with the treated oocysts and the oocyst output in the feces after inoculation was examined. In C. parvum and chicken Cryptosporidium sp., the oocysts were not detected from mice or chickens which were received oocysts heated at 55°C for 30 sec, 60°C for 15 sec and 70°C for 5 sec. In C. muris, the oocysts were not detected from mice which were received oocysts heated at 55°C for 15 sec, 60°C for 15 sec and 70°C for 5 sec. Consequently, it was clarified that the infectivity of Cryptosporidium oocysts to mice and chickens was lost by heating at 55°C for 30 sec, 60°C for 15 sec and 70°C for 5 sec.

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Rumen ciliate composition of river-type water buffalo and goat in Nepal was surveyed. As the result of survey, 13 genera representing 52 species and 20 formae of the ciliates were identified. Of them 13 genera with 44 species and 9 formae were found from the water buffalo and 8 genera with 21 species and 12 formae from the goat. The present paper shows the first report of Hsiungella triciliata, Entodinium brevispinum, E. convexum, E. javanicum, E. rectangulatum f. rectangulatum, E. rectangulatum f. lobosospinosum, Diplodinium nanum, D. psittaceum, D. sinhalicum and Ostracodinium quadrivesiculatum from water buffalo and Epidinium ecaudatum f. parvicaudatum from goat.

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Monoclonal antibodies (MAbs), R1 and M5, were established against the second-generation schizont of Leucocytozoon caulleryi (L. caulleryi). Both antibodies reacted to membrane and internal structure proteins of the second-generation schizont by immunofluorescence microscopy. Molecular weight of the second-generation schizont (2GS) antigen was analyzed by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. At least 40 protein bands were detected in 2GS antigen by SDS-PAGE under reduced condition and ranged from 10 to 270 kDa. MAb R1 reacted to polypeptides of 150-268 kDa in 2GS antigen, whereas MAb M5 did with that of 66 kDa. Injection with a protein of 2GS antigen fractionated by affinity chromatography using MAbs R1 and M5 protected chickens against challenge with sporozoites of L. caulleryi. These results suggest that MAbs, R1 and M5, recognize 2GS antigen of L. caulleryi.

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A 6-year-old male red squirrel (Sciurus vulgaris orientis) developed bilateral tumors of upper and lower eyelids. The tumors in the left lid recurred despite surgical removal. Necropsy revealed metastasis to the lung. The neoplastic cells were epithelioid and highly pleomorphic, and only a few cells contained melanin granules. Occasionally melanoma cells were immunoreactive for S100, neuron-specific enolase and vimentin, and a small number of cells for cytokeratin. Ultrastructurally, the presence of premelanosomes was confirmed in the cytoplasm. Possible presence of cytokeratin-positive neoplastic melanocytes should be taken into account when differentiating a nonpigmented epithelioid melanoma from other tumors such as anaplastic carcinomas.

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An 11-month-old male mixed breed dog was euthanized due to two months history of vomiting and anorexia. At necropsy, numerous, multifocal or coalescing, firm, protruding nodules, 5 to 40 mm in diameter were scattered throughout the mesentery and omentum. Histologically and immunohistochemically, the nodules were diagnosed as malignant mesothelioma. Metastasis to the regional mesenteric, mediastinal and tracheobronchial lymph nodes were observed.

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Complex odontoma from a female Sprague-Dawley rat is described histopathologically. Necropsy revealed a hard (bony), white mass (3.0 × 3.0 × 2.1 cm) on the left mandible. Microscopically, the mass consisted of islands or nests of epithelial and mesenchymal elements that formed abortive tooth structures. In other areas, tooth formation consisted of a pulp cavity lined by layers of odontoblasts, dentin, enamel, and ameloblasts. Concerning all features of normal tooth formation which was differentiated and mineralized yet completely disorganized, the diagnosis of complex odontoma was recommended.

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To record the somatosensory evoked potentials (SEPs) produced by stimulation of tail nerves and determine the effects of acute compression of the cauda equina on SEPs. The subjects were 10 adult Beagles. SEPs were recorded after stimulating the dorsomedial nerves (DMN) innervating the tail. The cauda equina was compressed using a balloon catheter inserted into the vertebral arch. In SEPs, two negative and one positive peak were often observed. The compression of the cauda equina caused significant depression of the positive component. The SEPs produced by stimulation of the DMN reflect the activities of ascending neuronal pathways above the coccygeal spinal segments and may be a useful tool for examining cauda equina syndrome.

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A Shetland sheepdog with epilepsy refractory to antiepileptic drugs was brought to the division of Veterinary Radiology at Nippon Veterinary and Animal Science University. Scalp electroencephalography and computed tomography was performed, but no abnormality was detected in either examination. To obtain detailed information, electrodes were implanted on the dura mater, and the electrocorticogram (ECoG) was recorded. In the ECoG, sporadic spikes were detected in the left parietal region, suggesting the presence of the epileptic focus in this region. After the dog's death, abnormalities of gyri were found in the region where spikes were detected in the ECoG. On histopathological examination, laminar malacia of the cingulate gyrus was observed. Furthermore, in the hippocampus, neuronal loss of pyramidal cells was observed.

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To set productivity standards and targets, and investigate inter-relationships between key measurements in swine breeding herds, farm productivity measurements were analyzed on 87 Japanese commercial farms in 14 prefectures. The 87 herds were ranked on the basis of number of pigs weaned per mated female per year (PWMFY), and 23 herds in the upper 25th percentile of this ranking were designated as high-performing farms. Productivity measurements on the high-performing farms were compared with values for the remaining farms. The high-performing farms had shorter farrowing intervals, greater litters per mated female per year (LMFY), greater pigs weaned per sow (PWS), and greater mean parity of culled sows than the remaining farms (P<0.01). No difference in lactation duration was found between the two groups (P>0.10). For both farm groups, correlations of key reproductive measurements were determined. Lactation duration was not correlated with LMFY, PWS and PWMFY on the high-performing farms, while short lactation duration was correlated with greater LMFY and PWMFY on the remaining farms (P<0.01). In contrast to lactation duration, farrowing interval was correlated with PWS on the high-performing farms, but not on the remaining farms. Mean parity of culled sows were correlated to PWS and pigs born alive per sow on the high performing farms, but not with any measurements on the remaining farms. These results suggest that high-performing farms have used different herd management from the remaining farms.

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Remodeling of uterine endometrial extracellular matrix (ECM) is pivotal to successful implantation and placentation, and has been well described in the rodents and humans. However, bovine endometrial ECM remodeling is still vaguely defined, especially at the time of implantation. Therefore, this study investigated the distribution of four ECMs namely, types I and IV collagen, laminin and fibronectin, from days 0 to 30 of gestation in bovine endometrium by immunofluorescence microscopy. A change in the distribution pattern of ECMs was evident by day 14 of gestation as features at this stage were clearly different from those of day 14 of the estrous cycle. The immunoreactivity of type I collagen, fibronectin and laminin decreased from day 14 of gestation and was obscured by day 24 of gestation. The type I collagen fibers formed were of thinner consistency than those of the estrous cycle and showed a coarser meshwork within the epithelium sites during the implantation period. In addition, the type IV collagen and laminin immunoreactivities of epithelial basement membrane also remarkably declined at exactly the same time. By day 30 of gestation, the four ECMs had regenerated with the formation of the placentome. In conclusion, this study reveals that remodeling of ECM is essential for the successful establishment of pregnancy in the bovine.

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At present, the effect of cyclin D2 implicated in cell cycle regulation, differentiation, and oncogenic transformation is not fully confirmed. To better elucidate the role of cyclin D2 in controling the cell proliferation, cyclin D2 expression level was determined at the early initiation and promotion stages during the in vitro two-stage transformation process of Balb/3T3 A31 cells. N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-induced G2/M-arrested cells expressed low level of cyclin D2 mRNA, while the contact-inhibited nonproliferating cells expressed high level of cyclin D2 mRNA. In the transformed proliferating cells at the promotion stage, cyclin D2 mRNA was not expressed. These data suggest that cyclin D2 expression may be associated with the type of growth arrest and nonproliferating state, but not with the cell proliferation and transformation.

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Butyl p-hydroxybenzoic acid (butyl paraben, BP) is widely used as a preservative in food and cosmetic products. Routledge et al showed that BP is weakly estrogenic in both in vitro and in vivo (rat uterotrophic) analyses. We investigated whether maternal exposures to BP during gestation and lactation periods affected the development of the reproductive organs of the F1 offspring. Pregnant Sprague-Dawley rats were injected subcutaneously with 100 or 200 mg/kg of BP from gestation day (GD) 6 to postnatal day (PND) 20. In the group exposed to 200 mg/kg of BP, the proportion of pups born alive and the proportion of pups surviving to weaning were decreased. The body weights of female offspring were significantly decreased at PND 49. The weights of testes, seminal vesicles and prostate glands were significantly decreased in rats exposed to 100 mg/kg of BP on PND 49. In contrast, the weights of female reproductive organs were not affected by BP. The sperm count and the sperm motile activity in the epididymis were significantly decreased at doses of 100 and 200 mg/kg of BP. In accordance with the sperm count in the epididymis, the number of round spermatids and elongated spermatids in the seminiferous tubule (stage VII) were significantly decreased by BP. Testicular expression of estrogen receptor (ER)-α and ER-β mRNA was significantly increased in 200 mg/kg of BP treated group at PND 90. Taken together, these results indicated that maternal exposure of BP might have adverse effects on the F1 male offspring.

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