Aquaporins (AQPs) constitute a family of water channels that facilitate membrane water permeability in various tissues of animals. In this study, we compared the expression and localization of AQPs in the respiratory system of the musk shrew (Suncus murinus), which is an insectivore, and the rat by immunohistochemical methods. In both the musk shrew and the rat, AQP1 was expressed throughout the airway in endothelial cells of subepithelial blood vessels and in nasal submucosal fibroblasts. AQP3 and AQP4 were detected in neither the epithelium nor the subepithelial layer of the musk shrew airway, but were abundant in the rat airway epithelium. Musk shrew AQP5 was distributed in the superficial epithelial cells facing the airspaces and in submucosal glandular cells, but, unlike in the rat, not in lung alveolar cells. Additionally, the expression patterns of AQP4 and AQP5 of the musk shrew were partly similar to those of the human previously reported, absence of AQP4 and presence of AQP5 in the upper airway. The expression differences of AQPs between species in the airway indicate that the physiological importance of each AQP may be different in each species.

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Tumor necrosis factor (TNF) receptors (TNF-R)-mediated cell survival or apoptosis has been demonstrated in many cells, but little is known about survival or apoptotic signals via TNF-R1 in tendinocytes. In this study, we focused on four signaling factors, TNFα, TNF-R1, TNFR-associated factor2 (TRAF2) and caspase-3, in order to elucidate the signaling events in tendinocytes. Samples were obtained from normal, inflamed and scar-formed equine superficial digital flexor tendons. To detect these signaling factors, samples were subjected to immunohistochemistry and Western blot analysis, and some samples were also subjected to reverse transcription-polymerase chain reaction (RT-PCR), PCR-Southern blot analysis and in situ hybridization to detect the expression of TNFα mRNA. Distribution of the four factors differed depending on the tendon condition, normal, inflamed or scar-formed. In the normal tendon, large amounts of TRAF2 were found in tendinocytes, but the amounts of TNF-R1 were small. TNFα mRNA was expressed most highly in the inflamed tendon. TNF-R1, which was only faintly detected in the normal tendon, was detected at a high level in the inflamed tendon, and the amounts of TRAF2 and caspase-3 also increased. Activated caspase-3 was only detected in the inflamed tendon. TNFα mRNA was also expressed in the scar-formed tendon, though it showed weak signals, and the expression levels of TNF-R1, TRAF2 and caspase-3 proteins were very low. Two distinct intracellular signaling pathways of TNFα, which lead to cell survival and apoptosis, might be present in tendinocytes mediated through TNF-R1. These results, which reflect the dynamism of TNFα, provide important clues for means to prevent tendinopathy.

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In this study, we have examined the possible existence of astrocyte regional heterogeneity in thrombin effect on astrocyte stellation. Neonatal astrocytes were cultured for 2 weeks from six different regions of the neonatal rat brain, including the cerebral cortex, hippocampus, brainstem, midbrain, hypothalamus and cerebellum. Culture medium was changed to DMEM containing 8-CPT-cyclic AMP (cAMP) or isoproterenol plus various concentrations of thrombin for 2 hr. Thrombin effectively blocked both cAMP- and isoproterenol-induced cell stellation in a dose-dependent manner in all regional astrocytes except cerebellar astrocytes. RT-PCR analysis showed that thrombin receptor mRNA was expressed in all regional astrocytes, suggesting that cerebellar astrocytes may maintain a unique signaling pathway downstream of the thrombin receptor.

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The resin casts of the respiratory and vascular systems in pigeon lung were examined using a scanning electron microscope. The primary bronchi branched to form many secondary bronchi that anastomosed with each other via the parabronchi. Numerous infundibula protruded from the parabronchi via the atria and ramified into the air capillaries. The pulmonary artery entered into the lung and branched into three vessels that coursed the interparabronchial parts. The intraparabronchial arterioles penetrated the gas-exchange tissue to form the anastomosing networks of blood capillaries. The observation of the double casts of the respiratory and vascular systems revealed three-dimensional complicated networks of air capillaries and blood capillaries.

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We examined the 12 antimicrobial susceptibilities of 175 E. coli isolates from sick cattle and pigs by an agar dilution method. Resistance was found in 78.3% of isolates for oxytetracycline, 70.3% of isolates for dihydrostreptomycin, and 49.1% of isolates for ampicillin. When compared with healthy animals reported by Kijima-Tanaka et al., resistance rates for 11 antimicrobial agents were higher in sick cattle than in healthy cattle, and resistance rates for all antimicrobial agents were higher in sick pigs than in healthy pigs. Comparing cattle and pigs, resistance rates to colistin was higher in porcine isolates than in bovine isolates, but was lower in porcine isolates than in bovine isolates for cefazolin. With regard to the association of virulence factors, higher resistance rates to colistin and enrofloxacin were observed in STEC (61 strains) than in non-STEC (57 strains) among porcine isolates, while there were no significant differences in bovine isolates. In conclusion, these results can be considered helpful for adequate selection and prudent use of antimicrobial agents for several types of colibacillosis.

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Mammary tumors are the most common tumor type in women as well as in female dogs. The BRCA2 gene encodes a large nuclear protein that is involved in DNA repair, and mutations in the human BRCA2 confer an increased risk of female mammary tumors. The BRCA2 protein acts as a tumor suppressor, and inactivation of BRCA2 by loss of heterozygosity is implicated in mammary carcinogenesis. In this study, to establish an appropriate polymorphic marker for loss of heterozygosity analysis of the canine BRCA2, we analyzed the genomic sequences of the exon 27 regions of 30 mammary-tumor-bearing and 21 tumor-free dogs. In addition to 10204ins/delAAA, which is the only polymorphism previously identified for the canine BRCA2 locus, we discovered four novel single nucleotide polymorphisms. The analysis of these five polymorphisms revealed the presence of four allele types. Since 10204ins/delAAA was the most common of the five polymorphisms identified, we developed a PCR-based assay method to assay for this polymorphism. We believe that this method is valuable for loss of heterozygosity analysis of the canine BRCA2 gene in tumor pathogenesis.

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Age-associated changes of magnetic resonance imaging (MRI) on the brain were evaluated in 19 beagle dogs aged from 8-month- to 16-year-old. A significant correlation of the volume of lateral ventricle space was observed in the dogs with age advanced, however, no correlation was found between hippocampus size and the aging. The hypo-intensity areas on T2-weighted MRI were detected in globus pallidus and substantia nigra with a significant correlation of both intensity ratios to lateral ventricle with age advanced. These areas were coincided with the accumulation of iron in the slice of the brain with Perls' staining. In addition, hyper-intensity area, suggesting perivascular demyelination with fluid-filled space, was also observed in white matter surrounding the lateral ventricle on T2-weighted MRI. These results suggested that age-associated changes of T2-weighted MRI were developed in the dog brain, especially in globus pallidus, substantia nigra, and white matter surrounding lateral ventricle, like as those reported in the human brain.

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γ-aminobutyric acid (GABA, 30 mg/kg) was administered to aged dogs with recent history of veterinary clinic visits (mean age: 15.3 years old) once daily for 2 weeks by mixing with food. Their owners subjectively evaluated the effects of GABA on behavioral signs often associated with aging in the dogs. Improvement in some of behavioral signs was notable without any observable adverse effects. Dogs administered with GABA tended to exhibit improvement in emotional states and signs may be caused by neurovegetable dysfunction, though effects on cognitive dysfunction syndrome were not always observed. Thus, GABA administration may be one of the effective means of improving the quality of life of aged dogs.

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Anti-bacterial activity of two synthesized oligopeptides, RLYLRIGRR-NH₂ (peptide A) and RLRLRIGRR-NH₂ (peptide B), both which based on a putative active site of defensin, an anti-bacterial peptide from the beetle Allomyrina dichotoma, was examined by macroscopic and histopathologic assessment during the course of infection in mice inoculated with methicillin-resistant Staphylococcus aureus (MRSA) in vivo. Both peptides A and B decreased the mortality of mice inoculated with MRSA. Peptides A and B decreased the macroscopical and histopathological lesions by MRSA infection in mice even seven days after the challenge. The anti-bacterial activity of peptides A and B has a therapeutic effect on MRSA infection in mice even seven days after being challenged.

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We cloned five new subtypes of cDNA encoding canine interferon-α (CaIFN-α) from a canine epithelial cell line. CaIFN-αs were divided into two groups by amino acid sequences and a molecular phylogenic tree. Two subtypes of them were expressed in Escherichia coli, and IFN proteins were purified. Recombinant CaIFN-αs were highly species-specific and showed antiviral activity against Vesicular stomatitis New Jersey virus and canine adenovirus-1 , but not against canine herpesvirus-1.

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This study aimed to establish and standardize a breath test that uses ¹³C-acetate in a liquid diet for evaluation of gastric emptying in horses. Seven adult healthy thoroughbreds were used in this study. They were given ¹³C-acetate (125 mg, 250 mg, or 500 mg) in a test meal (2000 ml liquid diet) via an intranasal catheter. ¹³C concentrations in the exhaled CO₂ were measured in samples taken before and after test meal administration using an infrared absorption spectroscope. In the 500 mg ¹³C-acetate group, Δ¹³CO₂ showed a steep gradient immediately after meal administration compared to the 125 mg and 250 mg groups. Therefore, t_max in the 500 mg group was easier to determine than in the 125 mg and 250 mg groups. In the 500 mg group, GEC, half-empty time (t1/2), calculated t_max (t_lag), and t_max were 1.95 ± 0.28 (mean ± SD), 229.2 ± 57.0 (min), 139.2 ± 22.2 (min), and 124.0 ± 28.4, respectively. Differences in CV observed in the 500 mg group were lower than those in the 125 mg and 250 mg groups. This study demonstrates that the ¹³C-acetate breath test is useful for evaluating gastric emptying in horses since it is non-invasive and does not require set up of special facilities or equipment. Optimum evaluation of gastric emptying in horses can be achieved with 500 mg of ¹³C-acetate given in a liquid diet.

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A 4-year-old female Siberian Husky was diagnosed with pyogranulomatous steatitis at the site of a recurrence of left anal sac rupture (day 1). Carprofen and orbifloxacin were given for 13 days without improvement. A single dose of meloxicam was administered prior to surgical resection of the anal sac, and based on elevated liver enzyme activity, liver supportive therapy was initiated. The dog received carprofen and orbifloxacin orally on the evening of day 14. The dog became anorectic the following morning, and began vomiting. Despite supportive therapy, the dog was unresponsive to treatment and died on day 16. Postmortem examination revealed severe vacuolar change and acute necrosis of hepatocytes consistent with carprofen and meloxicam induced-toxicosis.

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The genetic variability of 182 unrelated mongrel dogs living in various areas of Japan (from Hokkaido to Okinawa) was studied by collecting their blood. Ten microsatellite loci were chosen from different autosomal chromosomes. After combining a few rare adjoining alleles to allelic classes, it was confirmed that the Hardy-Weinberg equilibrium was attained in each locus. The polymorphic information contents (PICs) of the loci, Ren37A11, Ren48E01, AHTk253, ZuBeCa30, Ren277K09, Ren42N13, AHT130, PEZ03, PEZ12, and AHT121, were 0.58, 0.63, 0.67, 0.67, 0.68, 0.71, 0.79, 0.80, 0.80, and 0.80, and the power of discriminations (PDs) were 0.80, 0.85, 0.87, 0.88, 0.88, 0.89, 0.94, 0.94, 0.94, and 0.94, respectively. The combined mean exclusion chance (MEC) was 0.9995, indicating that these microsatellite loci are useful for kinship testing of Japanese dogs.

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The receptors for endothelin (ET) family, ET_A and ET_B, were molecularly cloned and the expression of ET_A and ET_B as well as preproendothelin-1 (PPET-1, precursor of ET-1) was examined in normal canine tissues by RT-PCR. The entire open reading frames of the canine ET_A and ET_B were shown to encode 427 and 442 amino acid residues, respectively, showing from 87.4 to 97.3% sequence similarity to human, mouse, and rat counterparts. ET_A and ET_B mRNAs were ubiquitously expressed in a variety of canine tissues in this study and PPET-1 mRNA was detected in the tissues except for heart and liver. It was speculated that ET could play an important role in physiological events in most of the organs.

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A Japanese Black calf, 3 day-old male, showed severe ataxia, lateral recumbency, and opisthotonos at the birth. Histopathological examinations revealed severe status spongiosis throughout the central nervous system. Numerous vacuoles within the neuropile varying in size and shape were observed in both formalin-fixed paraffin and cryostat sections. In the lesions, a limited number of spheroids and macrophages were observed within the myelin sheaths with very mild astrogliosis. These vacuoles were negative for both periodic acid Schiff and Sudan black stains. The clinical and histopathological features were almost in conformity with those of bovine maple syrup urine disease (MSUD). Although we could not confirm completely the etiology, congenital hereditary neurological diseases including MSUD are considerable as the possible disease entry in the present case.

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We previously reported that extremely low frequency electric fields (ELF-EFs) affect energy metabolism in stressed conditions. To further confirm this, the effect of exposure to ELF-EFs on the experimental ischemic rat was examined. The test was based on a comparison of rats treated with EF alone, ischemic surgery alone, the combination of EF with ischemic surgery, or no treatment (double sham). The EF condition used in this study was an alternating current of 50 Hz EF at 17 500 V/m intensity for 15 min per day. The exposure to EF in ischemic rats significantly decreased plasma levels of free fatty acids and triglycerides, compared to those of the no treatment or EF alone group. The plasma lactate levels of two ischemic groups peaked on experimental day-4 and gradually decreased until the end of the study. The changes in the lactate levels induced by ischemia did not show any difference between rats treated with ischemia alone or a combination of ischemia with an EF. Any changes in plasma levels of glucose and creatine phosphokinase activity were not influenced by EF treatment. These results indicate that the EF effect on glycolysis parameters, plasma lactate or glucose levels, does not appear in a highly stressed condition and that EF effects varied dependent on the condition of organism but ELF-EF used in this study have impact on lipid metabolism parameter in a hind-limb ischemic rat. However, further studies are needed to elucidate the association of ELF-EF with the lipid metabolism system.

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A large-scale outbreak of food poisoning caused by consumption of skimmed milk powder contaminated with staphylococcal enterotoxin A (SEA) occurred in Japan. No viable Staphylococcus aureus was detected in the skimmed milk powder, however, sea and nuc genes of S. aureus were detected in it by PCR. The number of S. aureus in skimmed milk powder was estimated by quantitative real-time PCR.

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A 4-year-old, neutered male Maltese presented with a 2-month history of right hemiparesis. The radiographic findings revealed bone lysis, and sclerotic changes in the right section of the fifth and sixth cervical bones with a mild radiolucent mass around the lesion. The magnetic resonance imaging revealed a hyperintense mass located in the region extending from the muscles to the bones and compressing the spinal cord. The mass was removed via a hemilaminectomy in the cervical area using the ventral and dorsal approach, and a histological examination confirmed that it was adipose tissue. An infiltrative lipoma was diagnosed based on these findings. The dog has ambulated normally for 24 months since undergoing surgery.

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The incidence of different types of luteal activity postpartum and their effect on reproductive performance were studied in 21 postpartum dairy cows. Progesterone concentrations in defatted milk collected 3 times a week were determined by EIA. Reproductive tract examination was undertaken every other week postpartum. Body weight and body condition score (BCS) were measured before and after calving and the average 100-day milk yield was calculated. Nine (42.9%) cows had normal ovarian activity (first luteal activity ≤ 50 days postpartum followed by regular cycles), 5 (23.8%) had prolonged luteal phase (PLP; ovarian cycle with luteal activity ≥ 20 days pre-service) and in 7 (33.3%) cows the first luteal activity was shown later than 50 days postpartum (DOV). When compared with normal cows, both PLP and DOV had longer interval to first insemination (63.1 ± 22.0 days versus 77.6 ± 21.6 and 93.0 ± 22.3 days, P<0.05 and P<0.01, respectively), lower first insemination conception rate (88.9% versus 0.0% and 57.1%, P<0.01 and P<0.05, respectively) and greater BCS loss (0.81 ± 0.2 versus 1.05 ± 0.21 and 1.04 ± 0.10, respectively, P<0.01). Cows with PLP showed longer interval to uterine involution than normal and DOV groups (54.0 ± 8.3 days versus 42.4 ± 5.5 and 43.3 ± 8.3 days, respectively, P<0.01) and higher 100-day milk yield (38.8 ± 2.7 kg versus 33.6 ± 4.7 and 29.9 ± 6.1 kg, respectively, P<0.01). In conclusion, more than half of the cows had abnormal luteal activity postpartum, which adversely affected reproductive performance.

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Carcinogenicity and chronic toxicity of para-dichlorobenzene (p-DCB) were examined by exposing 50 BDF₁ mice and 50 F344 rats of both sexes by inhalation to p-DCB vapor at a target concentration of 0 (control), 20, 75 or 300 ppm for 6 hr/day, 5 days/week and 2 years. Incidences of hepatocellular carcinomas, hepatoblastomas and hepatic histiocytic sarcomas in the 300 ppm-exposed male mice, and hepatocellular adenomas and carcinomas and hepatoblastomas in the 300 ppm-exposed female mice were increased. An increase in the incidences of most of those liver tumors was dose-related. No increase in tumor incidence was found in any p-DCB-exposed rat of either sex. Centrilobular hypertrophy of hepatocytes and papillary mineralization and pelvic urothelial hyperplasia of the kidney were noted in the 300 ppm-exposed male rats. Treatment- and age-related increases in incidences of the eosinophilic globules of the respiratory and olfactory epithelia in female rats and incidences of the respiratory metaplasia of the nasal gland epithelium in mice and rats and the olfactory epithelium in mice were noted. The nasal lesion was the most sensitive endpoint of chronic inhalation toxicity. Induction of the mouse hepatocarcinogenicity and lack of the rat nephrocarcinogenicity found in the present study were compared with the mouse liver tumors and the rat renal tumors reported by the NTP gavage study, and discussed in light of the estimated p-DCB uptake into the body through the inhalation and the oral administration.

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