We studied the change in the hypothalamo-pituitary-adrenal gland (HPA) axis upon adding prior toluene inhalation to our previous formaldehyde inhalation experiments to determine whether short term exposure to relatively high levels of toluene triggers multiple chemical sensitivity (MCS). Data come from immunocytochemical, morphometrical and RT-PCR measurements. Four groups of adult female mice were exposed to differing concentrations (0, 80, 400, and 2,000 ppb) of formaldehyde for 16 hr/day, 5 days/week for twelve weeks, after the mice were exposed intranasally to 500 ppm toluene per mouse for 6 hr/day, for 3 days. We found that the number of corticotropin releasing hormone (CRH)-immunoreactive (ir) neurons was up-regulated according to the amount of formaldehyde as well as inhalation of formaldehyde alone in our previous experiment. The proportion of adrenocorticotropin hormone (ACTH)-ir cells increased according to the formaldehyde concentration, though there was no significant difference between the 400 and 2,000 groups. The number of ACTH-ir cells was higher in the 400 group than in the other groups (0, 80, and 2,000). Expression of ACTH-mRNA was also up-regulated according to the quantity of formaldehyde. The sinusoid in the anterior pituitary showed more dilatation in the 400 and 2,000 groups than in the control group, especially in the 2,000 group. We propose that exposure to toluene prior to inhalation of formaldehyde has no effect on the HPA axis and as a trigger of MCS, although greater sinusoid dilatation was found in the anterior pituitary gland at higher concentrations of formaldehyde.
Nucleotide sequences of 16S rDNA and rpoB gene of 25 bovine and 6 ovine Histophilus somni strains were determined to detect subtle differences between the host animal species. The 1465 nucleotide residues of the 16S rDNA exhibited levels of sequence similarities of 99.4% or more. The high sequence similarity of the 16S rDNA of recently described species H. somni was confirmed in the 31 strains from cattle and sheep. These results suggested that the intra-specific diversity of 16S rDNA was limited in bovine and ovine strains of H. somni. The specific association of strains was also observed in the 311 bp region of rpoB gene which sequence similarities were 98.6% or more. However, the phylogenetic tree analysis of the rpoB gene showed that the ovine strains appeared to form a subgroup recovered in 70% of the bootstrap trees. In the 311 bp region of the ovine strains, a HincII restriction endonuclease site was detected. The PCR-amplified rpoB DNA of 46 bovine and 20 ovine H. somni strains were examined for the digestion with HincII. As the results, 17 strains of ovine strains were cleaved by the enzyme but none of the bovine strains appeared to possess the restriction site. The restriction enzyme analysis of rpoB gene may be useful to differentiate ovine strains from bovine strains of H. somni.
Staphylococci were isolated from the external auditory meatus in 14 (48.3%) of 29 dogs affected with otitis externa (OE dogs) and 28 (68.3%) of 41 dogs without OE (non-OE dogs). Twenty-two OE isolates were identified as belonging to 12 species, and 42 non-OE isolates were identified as belonging to 13 species. The predominant species found in both OE and non-OE isolates were S. intermedius, and S. epidermidis. Thirty-eight (59.4%) of 64 isolates were resistant to one or more of the 17 antimicrobial agents tested. Resistance to PCG and ABPC was most frequent. S. schleiferi subsp. coagulans, a recent etiologic agent of canine OE, was isolated from OE and non-OE dogs. All of the 5 S. schleiferi subsp. coagulans isolates showed typical characteristics. No clear difference in the extracellular enzyme or toxin profiles, nor in the PFGE patterns, was demonstrated between the OE and non-OE isolates of S. schleiferi subsp. coagulans. A new PCR primer set specific for 16S rDNA was designed to identify strains of S. schleiferi subsp. coagulans. The amplified fragment was detected in all of the 5 isolates as well as the type strain GA 211 (=JCM 7470) and a reference strain GA 11, but was not detected in any strains of the related species, S. aureus, S. intermedius and S. hyicus. The PCR may allow a simple, rapid and precise identification of S. schleiferi subsp. coagulans, in addition to the standard tube test for free coagulase.
Paraoxonase 1 (PON1) is an enzyme associated with high-density lipoprotein (HDL) and has a protective effect against oxidation of lipoproteins in mammals. We investigated PON1 enzyme activities in bovine serum and its distribution among bovine serum lipoproteins. Paraoxonase activity and arylesterase activity in serum (152 Holstein cows and 42 Japanese Blacks) were 275 ± 55 U/ml and 130 ± 27 U/ml (mean ± SD), respectively. There was a high correlation (r=0.962) between the two enzyme activities, and the activity ratio of paraoxonase/arylesterase did not exhibit individual variation. More than 85% of both paraoxonase and arylesterase activities were detected in the HDL fraction separated by ultracentrifugation. The 43-kDa protein in the HDL fraction was identified as bovine PON1 by N-terminal amino acid sequence analysis. Bovine PON1 was purified by ultracentrifugation and preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and an anti-bovine PON1 antiserum was developed. The concentration of PON1 protein determined by immunoblotting was closely correlated (r=0.976) with paraoxonase activity in serum. Bovine HDL was further fractionated into subpopulations, and the distribution of PON1 was examined. Paraoxonase activity and PON1 protein increased with decreasing HDL size and approximately 60% of total paraoxonase activity was distributed in the heavy HDL fraction. The different distributions of PON1 among HDL subpopulations might be concerned to the function and metabolism of bovine HDL.
OmpL1 is a 31-kDa outer membrane protein characterized in 1993 and known to be expressed only in pathogenic Leptospira spp. Recombinant OmpL1 (GST-rOmpL1) was expressed for use as an ELISA antigen for the detection of anti-Leptospira antibodies. In immunoblot analysis, the protein reacted with sera of dogs infected with three different serotypes of Leptospira interrogans, while did not react with sera of dogs both uninfected negative controls and infected with Borrelia burgdorferi, which is closely related to Leptospira spp. Moreover, in ELISA using GST-rOmpL1, the optical density (O.D.) values from the positive controls were very high (1.125 ± 0.549). In contrast, the O.D. values from clinically healthy dogs and dogs with diseases other than leptospirosis were very low (0.109 ± 0.046 and 0.089 ± 0.046, respectively). These data suggest that the detection of anti-Leptospira antibodies by ELISA using the GST-rOmpL1 protein can be applied for diagnosis of canine leptospirosis.
Polymorphism of the PrP gene is a primary factor influencing susceptibility and incubation period in natural and experimental scrapie in sheep and goats. Polymorphisms of the caprine PrP gene in Japan were examined in 118 goats. Eight allelic variants and 19 genotypes were obtained. Amino acid polymorphisms were observed at 7 codons: 102, 142, 143, 240, 127, 146 and 211 (the latter 3 are novel polymorphisms). The polymorphisms at codons 142M and 143R, which are associated with the resistance to scrapie, were relatively rare in the present study. Thus, the present results provide information about the caprine PrP gene that may be useful for assessing the risk of goat scrapie.
This study was carried out to investigate the effect of ovariohysterectomy on vocalization during territorial aggression of German Shepherd dogs. Sixteen clinically healthy dogs of 5 to 10 months old were assigned randomly to one of two groups: ovariohysterectomy or control. Their behaviors and vocalizations induced by the approach of a stranger with a strange dog were recorded using digital camcorder at four and five months after surgery and were analysed. When territorial aggression was induced, dogs in ovariohysterectomized group showed more offensive territorial aggression. The bark was the most frequent vocalization. In this study, the average number of barks was 45 times in ovariohysterectomized group, and 26 times in the control group. The pitch of vocalization was significantly lower in ovariohysterectomized group than control group. First formant, second formant, third formant, and fourth formant frequency in ovariohysterectomized group, which represent the degree of sound energy in specific frequency, were lower than those of control group. Ovariohysterectomy of bitches may influence the frequency of aggressive vocalization and affect the acoustic feature of dogs' vocalization. Analysis of vocalization could be a useful method of evaluating the dogs' intention.
In this study values for total cholesterol and triglycerides were measured in 110 blood samples taken from 360 days pre-partum to 90 days post-partum in ten parturitions of six bottlenose dolphins, and in 75 blood samples when the dolphins were not pregnant as a control group. The average total cholesterol values in the second, third and fourth stages and in the puerperium were significantly higher than the average value of the control group by 11.0%, 30.2%, 19.3% and 13.4% respectively. The average triglycerides values for the third and fourth stages and in the puerperium were also significantly higher than those in the control group by 59.7%, 84.3%, and 42.1% respectively.
A total of 969 birds representing 121 species of 21 families from the West African nations of Cameroon, Equatorial Guinea and Ivory Coast were examined for haematozoa using thin blood smears; 277 individuals (28.6%) harbored blood parasites. The parasites identified included species of Haemoproteus (7.7% prevalence), Plasmodium (10.7%), Leucocytozoon (4.6%), and Trypanosoma (7.3%). In addition, microfilariae of filariid nematodes were present in 3.6% of the individuals examined. The birds were collected over a period of 12 years, from 1989-2001, from rainforest and ecotone habitats. We report a relatively high prevalence of parasites in colonial nesting birds, and two species of ground nesting birds. In addition, we compared data from bird species collected at a site identical to a previously published study, and did not find significant differences in parasite prevalence between the two years constituting two different seasons. Our results are also compared to other studies in Africa that implement similar and different methodologies.
The goblet cell (GC) and the intestinal mucus are important in preventing invasion of the mucosa by luminal microorgansisms. GC responses in the jejenum, cecum and colon of C57BL/6 mice during the course of infection with the large intestinal-tropic coccidian, Eimeria pragensis (E. pragensis), were investigated histologically. The numbers of large intestinal GCs (cecum and colon) gradually decreased (hypoplasia) in association with development of endogenous stages of parasite life cycle. The effect was transient and recovery of GC numbers was associated with resolution of coccidial infection. The jejunal GC numbers were not affected by E. pragensis infection. Clindamycin treatment in the infected mice reduced numbers of intracellular parasites and significantly increased the numbers of large intestinal GCs compared with untreated, infected mice.
Chinese hamsters were examined for the susceptibility to the infection with Babesia microti based on the hematological parameters during the course of infection. A marked decease in the RBC count, Ht value, Hb concentration, and an increase in WBC count due to the development of neutrophils or monocytes were recognized with the progress of parasitemia. Remarkable clinical findings were anemia and persistent infection with a low level of parasite burden in the chronic and convalescent stages. From these findings, it was concluded that Chinese hamsters were susceptible to infection with B. microti and would be useful for infection examination with the parasite.
Giardia intestinalis is recognized as a significant pathogen in humans and animals, causing diarrhea. Recent molecular studies indicate that G. intestinalis is composed of genetically distinct multiple genotypes. Therefore, it is valuable to distinguish among genotypes in the epidemiology of Giardia infection in humans and animals. Although G. intestinalis has been found in humans and animals in Japan, the genotype of isolates remains unclear except for several isolates from dogs, because identification has been performed only by conventional microscopy. We report herein the genotypes of G. intestinalis isolates distinguished by a phylogenetic analysis. G. intestinalis isolates originated from a patient and a calf were found to have Assemblage B and E, respectively.
To date, the majority of research on hypercholesterolemia has focused on the effects of a high cholesterol diet on atherosclerosis and coronary heart disease. The toxic effects of cholesterol on the liver and the relationship between the intake of a high cholesterol diet and hepatic fibrosis, however, have not been investigated clearly or histopathologically. Male Wistar rats were fed a diet supplemented with 1.0% cholesterol and 0.3% sodium cholate for 12 weeks. Rats were sacrificed and analyzed via blood biochemistry, traditional microscopy and immunohistochemistry. Following the feeding of this diet, the rates of aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase and total cholesterol in the rats were elevated consistently from week 3 and throughout the remainder of the experiment. From microscopic observation, hepatic necrosis, macrophage infiltration and steatosis increased markedly throughout the experiment. Hepatic fibrosis and myofibroblast proliferation were detected at weeks 9 and 12. Mast cell appearance was proportional to the degree of hepatic damage. These findings suggest that hepatic fibrosis is inducible by a high cholesterol diet and is likely the result of the interaction between several different cell types (i.e., macrophages, myofibroblasts, and mast cells) in an inflammatory milieu. Hypercholesterolemia should be considered as a risk factor for hepatic fibrosis as well as atherosclerosis and coronary artery disease.
A 3-month-old female tortoise-shell cat showing azotemia died with a marked swollen abdomen. Necropsy revealed a huge perirenal cyst (8.5 × 6.0 × 4.5 cm) on the ventral aspect of the right kidney. The cyst was filled with the pellucid yellow fluid with a smell of urine. The lumen was connected with irregularly dilated renal pelvis by a narrow channel passing through the renal parenchyma. The cyst was lined by epithelial cells and its wall was consisted of collagen fibers and smooth muscle cells as that of the renal pelvis and ureter. Renal parenchyma adjacent to the channel showed interstitial infiltration of the lymphoid cells. The cyst was a diverticulum of the renal pelvis due to an impaired development.
We report the case of a 4-year-old female woodchuck (Marmota monax) which presented with a white, firm and discrete mass in the hard palate. The mass extended into the oral cavity but it was well separated from the surrounding tissues. Histology of the tumor showed a malignant mesenchymal tumor with pleomorphic spindle cells varying in degrees of differentiation and density. The neoplastic cells had moderate amounts of granular or fibrillar eosinophilic cytoplasm with indistinct cell margins. Nuclei were oval to elongated and frequently blunt-ended with vesicular chromatin. Immunohistochemical study showed that the neoplastic cells expressed vimentin and alpha-smooth muscle actin but did not express desmin, pan-cytokeratin, and S-100. Therefore, histology and immunohistochemistry revealed that the tumor was oral leiomyosarcoma. Oral cavity is an extremely rare site for leiomyosarcoma and the present case is the first report of spontaneous oral leiomyosarcoma in animals.
A total of 444 samples of raw chicken meat (thighs, breasts, wings, livers, gizzards, hearts and ovaries) that retailed at 145 different supermarkets in 47 prefectures in Japan were examined for contamination with Staphylococcus aureus in association with its enterotoxigenicity. S. aureus was isolated from 292 (65.8%) of the samples, and from 131 of the 145 supermarkets. There was no significant difference in the detection rate of S. aureus according to the type of meat examined. About 80% of 714 isolates belonged to the poultry (57.1%) and human biotypes (22.1%). Seventy-eight (21.7%) of 360 isolates were enterotoxigenic and isolated from 78 samples in 53 supermarkets in 31 prefectures. Staphylococcal enterotoxins (SEs) produced were SEB (50 isolates), SEA (14), SEC (8), SED (2), SEA+SEB (2), and SEA+SEC (2). Most of the enterotoxigenic isolates belonged to the human and poultry biotypes, coagulase type VII, VIII or IV, and were lysed by phages of group III. Identical SE types, biotypes, coagulase types and pulsed-field gel electrophoresis (PFGE) patterns were shown in isolates from different types of meat at the same supermarket and from samples taken from different supermarkets in the same prefectures or in isolates from samples obtained from several different prefectures. Among the 50 SEB-producing isolates, 27 yielded three similar PFGE patterns that differed by only a few fragments, suggesting that they were closely related genetically. The three patterns were found in isolates of samples that retailed at 17 supermarkets in 11 prefectures, indicating that they may be disseminated among raw chicken meat in Japan.
Surveillance of chronic wasting disease (CWD) was conducted by performing Western blot analysis of tissue samples from 136 sika deer (Cervus nippon) killed by hunters in the Tokachi district of Hokkaido Island. No prion protein (PrPSc) associated with CWD was detected in any of the samples. To assess amino acid polymorphisms of the sika deer PrP gene, nucleotide sequencing of the PrP gene was performed. The only amino acid polymorphisms detected were 3 silent mutations at nucleotide positions 63, 225 and 408. These results suggest that sika deer in the Tokachi district are genetically homogeneous, and are not infected with CWD.
Clinicopathological features of mammary gland tumors (MGTs) in 101 dogs were evaluated retrospectively. The incidence of histological malignancy in 60 small- and 41 other-breed dogs were 25% and 58.5%, respectively. In 82 epithelial MGTs, small-sized tumors (< 3 cm) or non-invasive tumors were predominant in small breeds. In multivariate survival analysis, small breed (p=0.048) and lower stage of tumor cell invasion (p=0.006) were significantly associated with longer survival time. These results suggest that the incidence of histological or biological malignancy in MGTs is lower in small-breed dogs than in others.
Ovarian follicular dynamics and estrous synchronization after Gonadotropin-releasing hormone (GnRH) treatment at Controlled Internal Drug Releasing device (CIDR) insertion were investigated in Japanese Black cows. CIDR was inserted for eight cows at 7 days after estrus. Cows were allocated to either Group A: 8-day CIDR insertion with GnRH treatment on d 0 (n=4, d 0=CIDR insertion) or Group B: 8-day CIDR insertion (n=4). Both groups were injected with prostaglandin F2α (PGF2α) on d 7. Ultrasonography and blood sampling were performed twice daily. Intensive sampling was performed every 15 min for 8 hr to determine the pulsatile release of LH on d -1, d 5 and d 10. Three of four cows showed intermediate ovulation within 2 days after GnRH treatment during CIDR insertion in Group A, whereas no ovulation was found in Group B. Three of four cows in Group A and all four cows in Group B ovulated after CIDR removal. Plasma progesterone concentrations from d 3 to d 7 in three intermediate ovulatory cows in Group A (8.4 ± 1.6 ng/ml) was significantly higher than those in Group B (4.1 ± 1.2 ng/ml; 4 cows) during CIDR insertion (P<0.01). Interval to estrus and ovulation after CIDR removal was observed at 60.0 ± 12.0 hr and 76.0 ± 6.9 hr in three cows in Group A, and 75.0 ± 15.1 hr and 93.0 ± 20.5 hr in Group B, respectively. There was a significant increase in LH pulse frequency on d 10 compared on d -1 or d 5 in both groups (P<0.05), in addition those on d 10 in Group A tended to be higher than in Group B. As a result, GnRH treatment at CIDR insertion at 7 days after estrus induced intermediate ovulation with formation of corpus luteum (CL) and rather synchronized emergence of ovulatory follicle during CIDR insertion. These induced CL increased plasma progesterone concentrations and contributed to precise synchronization.
Akabane disease is an infection with clinical signs of congenital malformation and abortion in ruminants. Abnormal parturitions caused by Akabane disease result in great economic loss. The purpose of this study is to estimate the reduction in the milk yield from abnormal parturition due to Akabane disease. The data were collected from 33 Holstein cows on 11 farms. The animals had abnormal parturitions during the period from September 1998 to March 1999, and were diagnosed as having Akabane disease. The mean and standard deviation of the rate of reduction in the milk yield of 33 cows after abnormal parturition caused by Akabane disease was -11.4 ± 14.9%. The means and standard deviations of the rate of reduction of four cows calving abnormally at 220-239 days of gestation, nine cows calving abnormally at 240-270 days of gestation, and 20 cows calving abnormally at 271-300 days of gestation were -26.6 ± 24.7%, -14.7 ± 11.0%, and -6.9 ± 12.3%, respectively. In this study, we demonstrated that the rate of reduction in the milk yield in cows affected by Akabane disease was -11.4 ± 14.9%, but values as high as -26.6 ± 24.7% were reached in the comparison with the milk yield obtained after normal parturition.
Gap junctional intercellular communications (GJIC) contributes to neural function in development and differentiation of CNS. In this study, we have investigated the expression of GJIC during the differentiation of neuronal stem cells and 12-Ø-tetradecanoylphorbol-13-acetate (TPA)-induced neuronal stem cell-derived cells from rat brain. During neuronal stem cell differentiation, expressions of Cx43 and 32 were increased for the duration of 72 hr, however the effect were decreased on the 7d. In the neuronal stem cell-derived cells, pretreatments with p38 MAP kinase inhibitor, SB203580, and MEK inhibitor, PD98059, could protect GJIC against TPA-induced inhibition of GJIC. Our data suggest that GJIC plays an important role during neuronal stem cell differentiation, and ERK1/2 and p38 MAP kinase signaling pathway may be closely related functionally to regulate gap junction in rat neuronal stem cell-derived cells.
Pseudorabies virus (PRV) propagated in rabbit kidney-derived RK-13 cells (PRV-RK) was neutralized by serum obtained from specific pathogen-free pigs through the activation of complement. The virus-neutralizing activity of swine serum was lost after treatment with ethylene glycol-bis-aminoethylether-N,N,N',N'-tetraacetic acid (EGTA) or ethylenediaminetetraacetic acid (EDTA). Anti-C1q and anti-IgM antibodies also inhibited virus-neutralizing activity. Though IgG-depleted swine serum neutralized PRV, IgM and IgG-free swine serum lost virus-neutralizing activity. Pre-incubation of swine serum with RK-13 cells, but not with swine kidney-derived CPK cells, at 4°C eliminated the virus-neutralizing activity to PRV-RK. Results indicated that swine serum contained natural IgM against an antigen(s) on the RK-13 cell surface and that this surface antigen was integrated into the PRV envelope during the budding process. Thus the natural IgM in swine serum reacted with the RK-13 antigen on the viral envelope, activated the complement cascade and neutralized the PRV-RK.
Seroepidemiological surveys were performed on neutralizing antibody to bovine herpesvirus 2 (BoHV-2) among cattle in Japan. A total of 1,819 sera were collected from cattle in 27 prefectures from 1997 to 1998. Antibodies were detected in only 18 sera collected from 4 prefectures. However, the most prevalent areas of the infection were found in two islands located in the subtropical zone. Additional 353 sera were collected in three including these islands in 1999-2001.The antibody-positive rates in the farms in these islands ranged from 10% to 81.1%. It was confirmed that BoHV-2 was prevalent in these areas. However, the infection seemed to be latent, because no diseases have been noticed. This is the first report showing the presence of BoHV-2 infection among cattle in Japan.
Electron tomography (ET) is a new technique for high resolution, three-dimensional (3D) reconstruction of pleiomorphic macromolecular complexes, such as virus components. By employing this technique, we resolved the 3D structure of Ebola virus nucleocapsid-like (NC-like) structures in the cytoplasm of cells expressing NP, VP24, and VP35: the minimum components required to form these NC-like structures. Reconstruction of these tubular NC-like structures of Ebola virus showed them to be composed of left-handed helices spaced at short intervals, which is structurally consistent with other non-segmented negative-strand RNA viruses.