Q fever is a zoonotic disease caused by a rickettsia Coxiella burnetii. Since its first description in 1937, the disease has been found to be present in most countries of the world. Serological evidences of Q fever in humans and coxiellosis in animals were reported in Japan in the 1950s, however, systematic studies of the disease did not begin until the report of isolation of C. burnetii from an acute Q fever patient in 1989. In addition to the extensive information about epidemiology of the disease, the understanding of Japanese isolates of C. burnetii is increasing rapidly in recent years. In this review, the epidemiology of the disease along with some characteristics of isolates of C. burnetii in Japan is summarized in five sections, i.e., coxiellosis, Q fever, modes of spread of the infection, laboratory diagnosis of the infection and some characteristics of Japanese isolates. This review includes some recent, unpublished data from our and other groups.

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Epiphyseal growth plates of proximal tibiae in rats with high doses of vitamin A (V-A) were observed. Of 4 groups, each consisting of 5 rats, three groups were given V-A at doses, IU/100 g by body weight/day, of 50,000, 100,000, and 150,000, respectively. The other group rats were given no V-A (control). Rats were administered V-A for the 5 days from 4 weeks after birth and sacrificed at 12 weeks after birth. Three rats of the 150,000 IU group died during the period of observation. The decalcified sections were stained with hematoxylin-eosin or toluidine blue. In the ground sections, microradiography, backscattered electron imaging, and energy-dispersive X-ray microanalysis were performed. These observations suggest that the local disappearance of epiphyseal growth plates under high doses of V-A goes in the order of the increased doses through the process of (1) calcified cartilage areae appearing in the resting cell zone, (2) some of the calcified areae extending in the growth plate towards the diaphysial side, (3) bone tissue replacing the calcified areae, and (4) the local disappearing of the growth plate. Such a local disappearance may be formed in the stressed proximal regions of tibiae.

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The fine structural alterations of hepatocytes of Japanese monkeys under 4 days of fasting stress were analyzed morphometrically. One of the conspicuous alterations was the enlargement of mitochondria. The average diameter of mitochondria in fasting group increased to approximately 1.89-fold of that in control group, though their number did not change. The number of peroxisomes was 1.36-fold of that in control, though their area did not change. In addition, many of r-ER were swollen and were vesiculated. The appearance of bundle of actin-like stress fiber also increased in the fasting animals. The glycogen area as well as liver weight decreased in fasting group.

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The blood supply in the equine hoof was studied by a microvascular casting corrosion technique and scanning electron microscopy in combination with observations of sections of the decalcificated digit. The dermal lamella was observed at the hoof wall and the dermal papilla at the other parts of the hoof. The microvascular architecture of the dermal lamella differed from that of dermal papilla. The vascular cast in the dermal papillar regions indicated that each papilla contained two central vessels (artery and vein), which ran parallel to each other, and the capillary plexus surrounding these vessels. In the dermal lamella region, the vessels consisted of thin parallel sheets arranged in vertical rows. Each sheet was made of branched arteries and veins, both of which were sandwiched between capillary plexus. At the distal and proximal parts of the wall, the vascular casts of the papillae merged to form the vascular sheets of the dermal lamella.

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Inactivated oil-adjuvanted vaccines for ND, IB, and IC serotypes A and C (OILVAX NB₂AC) have been marketed from 1993. In the outdoors, various inoculation sites have been used in chickens because to make the inoculation procedure easier. We examined whether differences would be obtained in the antibody response according to the inoculation sites; the subcutaneous inoculation into the back of the neck for OILVAX use, and the thigh, lower thigh, breast and shoulder muscle for the possible application of the inoculation outdoors. The clear order was not found in the NDV-HI titer, IBV-SN titer against Nerima or TM-86 among the inoculation sites used during the examination period. The IC serotypes A and C HI titers did vary among the inoculation sites; the subcutaneous inoculation produced the highest antibody titer, and high antibody titers were observed in the order of lower thigh muscle ≥ thigh muscle > breast muscle ≥ shoulder muscle inoculation.

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The effects of an intravenous (iv) infusion of a small volume (5 ml/kg) or large volume (15 ml/kg) of hypertonic saline solution (HSS; 7.2%, 2,400 mOsmol/kg·H₂O) and those of an iv infusion of 5 ml/kg isotonic saline solution (ISS; 300 mOsmol/kg·H₂O) on plasma volume, arterial blood pressure, serum sodium concentrations and osmotic pressure were investigated in conscious heifers. Nine heifers (3 heifers/group) were monitored for 120 min after the initiation of fluid replacement. The relative plasma volume (rPV) in the 5 ml/kg HSS and 15 ml/kg HSS progressively increased to 137.7 ± 2.4% at t=5 min and 145.2 ± 5.4% at t=15 min, respectively. The expanding plasma volume in the 5 ml/kg HSS group remained at an up to 10% higher level until 120 min, but not in the 15 ml/kg HSS group. The 5 ml/kg HSS infusion induced transit high-osmotic (305.3 ± 4.0 mOsmol/kg·H₂O) and sodium levels (155.7 ± 3.5 mM/l) at t=5 min. However, the 15 ml/kg HSS infusion induced constant high-osmotic level (321.7-336.7 mOsmol/kg·H₂O) and hypernatremia (162.8-170.0 mM/l) from t=10 min to the rest of the experiment period. In the ISS and 5 ml/kg HSS groups, no changes in PaO₂ were observed. The 15 ml/kg HSS infusion induced a significant decrease in the partial pressure of oxygen at the t=30 min compared to the t=0 min values. On the basis of these findings, a small volume (5 ml/kg) HSS infusion can be rapidly and safely administered to cattle for expanding the plasma volume without inducing hypernatremia. A 5 ml/kg HSS infusion is thus recommended for the initial field resuscitation of cattle.

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The systolic, mean and diastolic pressures as well as the heart rate were mesured using the oscillometric method, on a total of 104 cats (60 cats in the normal group, and 44 in the renal disease group) which were brought into Azabu University Animal Hospital. The blood pressure in the normal group was systolic: 115.4 ± 10.1 mmHg, mean: 96.2 ± 12.2 mmHg, and diastolic: 73.7 ± 10.7 mmHg. Although no difference in heart rate, the renal disease group showed significantly (p<0.05) higher values for systolic, mean, and diastolic pressure when compared with the normal group. Moreover, when plasma renin activity, angiotensin I and II, and aldosterone concentrations were measured in other cats (11 normal and seven with chronic renal failure), all cats with chronic renal failure showed significantly (p<0.05) higher values than the normal group. It is, therefore, indicated that hypertension due to stimulating renin-angiotensin-aldosterone system may have manifested in cats with renal dysfunction.

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Fragile sites are non-randomly distributed chromosomal breaks and gaps observed in the cells cultivated under certain conditions. Feline fragile sites were analyzed using skin fibroblast strains after the treatments with aphidicolin and fluorodeoxyuridine in combination with caffeine. Three aphidicolin-induced fragile sites (A1q21, C2q13 and E1p21) as well as a folate-sensitive site (B1q14) were observed in all the 3 fibroblast strains tested for each treatment group. The loci in A1q21 and B1q14 are very close to that reported previously for peripheral blood lymphocytes and lung cells. Two chromosomal break points in C2q13 and E1p21 seem to be new fragile sites. Fifteen candidates for feline fragile sites were also assigned their locations in feline chromosomes. Both the incidence and distribution of feline fragile sites in skin fibroblasts seem to be different at least in part from those in lymphocytes.

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It is desirable to shorten expose time in ³H-autoradiography. We developed a new solid scintillator, a mixture of DPO, POPOP and Epon 812, for whole-body autoradiography. The new scintillator is originally in a sol form, but quickly transforms to a solid homogeneous film following exposure to room air. The new scintillator enabled whole-body autoradiography to be developed faster when compared with a liquid scintillator or commercially available reagents. We also demonstrated that the new scintillator gave consistently high counting performance and thus shortened duration of exposure when used in whole-body autoradiography, whereas commercially available enhancers were found to be unsuitable for autoradiography, resulting in dappled images. Furthermore the quantitative analyses of the autoradiograms by a densitometer demonstrated the highest density, and ratio with this new solid scintillator among those with a liquid scintillator and commercially available reagents. In conclusion, a new solid scintillator, a mixture of DPO, POPOP and Epon 812, is a useful and cost effective enhancer for the whole-body autoradiography of tritum compounds.

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Spontaneously activated MDV is rarely included in MDV-transformed cells, while it may influence the result of transcriptional analysis. A population consisting of 10³ MDV-transformed cells probably did not include spontaneously activated MDV, since the estimated frequency of MDV-transformed cells including activated MDV was below 0.01% according to limiting-dilution polymerase chain reaction (PCR) and the presence of the major early antigen pp38 in 6 transformed cell lines. Reverse transcriptase-PCR (RT-PCR) products corresponding to ICP27, pol, TK, US3, A41, gA, gB and UL50 genes were undetectable in 10³ cells by Southern hybridization of the RT-PCR products. Transcripts of the VP16 and SORF2 genes were detected in the 10³ cells of MSB-1, and the pp14 gene transcript was found in 10³ cells of RPL-1 but not in 10³ cells of HPRS-1, MOGA-1, MOGA-2, MSB-1 or MTB-1. A transcript corresponding to the ICP4 sequence was detected as a 0.7 kbp RT-PCR product in 10³ cells of these MDV cell lines but not in the retrovirus-transformed 1104B1 cell line. The transcript corresponding to the 0.7 kbp RT-PCR product suggested a splice by its size and sequence. Thus, transcriptional analysis of 10³ MDV-transformed cells revealed that the transcript corresponding to the ICP4 sequence was a common transcript in latently infected MDV-transformed cells, while most of the genes did not transcribe in these cells.

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Prevalence of antibody to Neospora caninum (NC) in Japanese dogs were examined. The antibody was positive in 15 of 48 dogs (31.3%) reared in the dairy farms that had case of the abortions due to NC infection or had the cattle seropositive to NC, whereas the prevalence was 7.1% (14 of 198 dogs) among the dogs kept in urban areas. In one dog breeder, all 17 Shetland sheepdogs older than 7 months were seropositive, and one pup was diagnosed as neosporosis 2 months before the first serological examination. The antibody titers of the dogs kept at this breeder were almost unchanged for 1.5 years. Serological evidence of the dogs in the dairy farms and urban areas indicates the transmission of NC between dogs and cattle. Also serological results of the dogs in one breeder may suggest the potential horizontal transmission among dogs.

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Cytological changes of feather pulp lesions (FPL) sampled chronologically from the same specific-pathogen free chickens inoculated with Marek's disease virus serotype 1 (MDV) were examined, comparing with their histological changes. The birds having Marek's disease (MD) lymphomas or nerve lesions exhibited the characteristic lesion changes on the cytological smears of FPL; the initial non-suppurative inflammatory to the late lymphomatous FPL. The birds having neither the MD visceral lymphomas nor the nerve lesions manifested only non-suppurative inflammatory FPL on the cytological smears throughout the experimental periods. Histological evaluation of FPL sampled from the same birds confirmed as above mentioned cytological results. From these results, the cytological evaluation of FPL proved to be an effective diagnostic and prognostic tool in foreseeing MD incidence.

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An 8-year-old, female mongrel dog had granulomatous lesions in the skull skin and gingiva of the left mandible. The lesions were macroscopically seen as grayish white papular granulomas, and microscopically consisted of numerous swollen macrophages and a few neutrophils without fibrocaseous necrosis. Macrophages contained many small oval or round-shaped yeast-like cells and a few rod-shaped organisms indicating a narrow based budding in their cytoplasm. The yeast-like cells were 2-5 μm (average 3.5 μm) in diameter, and appeared as a central, spherical, lightly basophilic body surrounded by a clear zone or "halo". The cell wall and central body were stained by the periodic acid-Shiff, Grocott's methenamine silver impregnation, or Gridley fungus method. Immunohistochemically, yeast-like cells were positive to anti-histoplasma yeast antibody, and rod-shaped organisms were positive to anti-histoplasma mycelial antibody. The present paper describes the first case of canine histoplasmosis in Japan.

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Peripheral neuroblastoma was found in a 1-year-old, male, Japanese black cattle (Case 1) and primitive neuroectodermal tumor was noted in 7-year-old, female, Japanese black cattle (Case 2). In Case 1, neoplastic tissue was replaced the right cranial vault and nasopharynx. A large, soft mass approximately 18 cm in diameter was also observed in the right mandibulopharyngeal area. In Case 2, a neoplastic mass of about 15 cm in diameter was found in the mandibulopharyngeal area. Histopathologically, massive necrosis showing a pseudopalisade arrangement was frequently observed in Case 1. On the contrary, Homer & Wright rosette formations of tumor cells were prominent in Case 2. Immunohistochemically, the proliferating cells in Case 1 were positive for vimentin, S-100, and neurofilament (NF) and those in Case 2 showed intense immunoreactivity for NF and neuron specific enolase, but were negative for vimentin and S-100. The different degrees of differentiation of the neoplastic cells originating from the neuroectoderm, might be reflected in their different morphological and immunohistochemical features.

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In the ovarian follicular fluid (FF) of Holstein cows, calcium (Ca) and magnesium (Mg) levels and their roles on thrombin generation were examined and compared with the blood samples. Total Ca levels in FF increased while the total Mg levels decreased with follicular development from preantral to preovulatory stage of follicles. These changes resulted in Ca values being significantly (p<0.05) higher in FF from the most developed follicles and the Mg values being significantly higher (p<0.05) in the least developed follicles. To determine whether the high level of Mg might function to regulate thrombin generation in FF as occurs in plasma, the influence of Mg supplementation of FF from various types of follicles was examined. In FF from small size follicles, Mg accelerated the prothrombin time, an estimation of the overall rate of thrombin production, although a similar effect was not observed in FF from medium and large size follicles. The addition of Mg to FF from all sizes of follicles resulted an inhibition in factor X activation. Since activation of factor X is a precursor step for thrombin formation it is concluded that Mg can function as a slow accelerator of thrombin generation in FF from follicles at the antral stage of development. It is likely to have a more important role in regulating the rate of thrombin generation as the follicle develops.

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The prevalence of Coxiella burnetii infection in 207 cattle with reproductive disorders was studied by using an indirect immunofluorescence (IF) test, nested polymerase chain reaction (PCR) and isolation. IF antibodies to phase I and phase II antigens of C. burnetii were found in 122 (58.9%) and 125 (60.4%) of the sera, respectively, and PCR-positives were found in 8 (3.9%) of the sera and in 51 (24.6%) of the milk samples. In addition, C. burnetii was isolated from 51 (24.6%) of the milk samples by inoculating laboratory mice. The results indicate that the IF test plus PCR are useful in the diagnosis of bovine coxiellosis. It is difficult to deny that dairy cattle with reproductive disorders would be one of the important reservoirs of C. burnetii responsible for infection in both animal and human populations in Japan.

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During the period from 1993 to 1996, a total of 27,497 Salmonella isolates from humans, chicken meat, ready-to-eat Thai foods and shrimps were serotyped to know the predominant serovars of Salmonella in humans and foods in Thailand. Seventy-two and 81 serovars of Salmonella were identified in human and food samples, respectively. The significance of foods as a vehicle for human salmonellosis was discussed from an epidemiological viewpoint.

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Objective of this study was to determine the ability of a delayed-implantation-associated protein (MW 170,000, DIAP170K) to inhibit DNA synthesis by mouse blastocysts. Mice were ovariectomized on day 3 of pregnancy and treated with daily injections with 1 mg progesterone till day 7 to induce delayed implantation. Blastocysts were collected on day 8 with or without a single injection of 25 ng estradiol-17β on day 7 that activates blastocyst metabolisms (activated blastocysts and delayed-implanting blastocysts respectively). DNA synthesis was determined by measuring [³H]thymidine incorportion by blastocysts. DIAP170K at 10 μg/ml suppressed resumption of DNA synthesis by delayed-implanting blastocysts and suppression was maximal at 50 μg/ml. However, DIAP170K did not affect DNA synthesis by blastocysts obtained on day 5 of pregnancy (normal blastocysts) and activated blastocysts. Resumption of DNA synthesis in the inner cell mass (ICM) and trophectoderm from delayed-implanting blastocysts was then separately assessed. DNA synthesis resumed in the trophectoderm of intact blastocysts during 24-hr culture but not in the trophectoderm cultured apart from the ICM. DIAP170K inhibited the resumption of DNA synthesis by the trophectoderm of intact delayed-implanting blastocysts but did not affect DNA synthesis by the ICM. In conclusion, DIAP170K inhibits resumption of DNA synthesis by trophectoderm of delayed-implanting blastocysts. This action of DIAP170K may play a central role in maintaining, but not achieving, dormancy of DNA synthesis by delayed-implanting blastocysts in mice.

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The reverse transcription polymerase chain reaction (RT-PCR) was applied to detect bovine viral diarrhea virus (BVDV) for the rapid diagnosis. The primers were selected from the p80 region of BVDV gene. The RT-PCR assay detected all of the 17 BVDV strains tested including cytopathogenic and non-cytopathogenic strains, while specific amplification was not observed from 17 bovine viruses other than BVDV. Detection limit of the assay was 10^1.5 TCID ₅₀/ml. Sera and organ samples were collected from four field bovine viral diarrhea-mucosal disease (BVD-MD) cases; mucosal disease, abortion, diarrhea and persistent infection. The RT-PCR assay detected BVDV from those samples more than conventional virus isolation method.

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