Characterization of the oral and faecal microbiota associated with atopic dermatitis in dogs selected from a purebred Shiba Inu colony.

Atopic dermatitis (AD) is a chronic and relapsing multifactorial inflammatory skin disease that also affects dogs. The oral and gut microbiota are associated with many disorders, including allergy. Few studies have addressed the oral and gut microbiota in dogs, although the skin microbiota has been studied relatively well in these animals. Here, we studied the AD-associated oral and gut microbiota in 16 healthy and 9 AD dogs from a purebred Shiba Inu colony. We found that the diversity of the oral microbiota was significantly different among the dogs, whereas no significant difference was observed in the gut microbiota. Moreover, a differential abundance analysis detected the Family_XIII_AD3011_group (Anaerovoracaceae) in the gut microbiota of AD dogs; however, no bacterial taxa were detected in the oral microbiota. Third, the comparison of the microbial co-occurrence patterns between AD and healthy dogs identified differential networks in which the bacteria in the oral microbiota that were most strongly associated with AD were related to human periodontitis, whereas those in the gut microbiota were related to dysbiosis and gut inflammation. These results suggest that AD can alter the oral and gut microbiota in dogs.

Aberrant forms of Yersinia pseudotuberculosis as spheroplasts and filaments in yersiniosis in squirrel monkeys.

This report describes atypical cases of yersiniosis in squirrel monkeys in which aberrant forms of Yersinia pseudotuberculosis were seen. There were 2 outbreaks due to yersiniosis in squirrel monkeys in Japan. The monkeys had systemic necrotizing and hemorrhagic lesions with Gram-negative rod-shaped bacilli and microthromboembolism in the kidneys. Some lesions contained filaments, globular bodies, and other pleomorphic forms of bacteria. All forms were usually seen in the same lesions, and those with pleomorphic morphology appeared to be an intermediate form between the rod-shaped bacteria and the filaments or globular bodies. In addition, they had strong immunolabeling for Y. pseudotuberculosis, as did the rod-shaped bacteria. Therefore, the globular bodies, filaments, and others are strongly suspected to be shape-changed bacilli of Y. pseudotuberculosis. These morphologically altered bacteria could cause errors in diagnosis since they resemble fungi or protozoa, and special staining techniques, including immunohistochemistry, can be helpful in establishing the correct diagnosis.

Genetic variation of Gongylonema pulchrum from wild animals and cattle in Japan based on ribosomal RNA and mitochondrial cytochrome c oxidase subunit I genes.

The gullet worm (Gongylonema pulchrum) has been recorded from a variety of mammals worldwide, including monkeys and humans. Due to its wide host range, it has been suggested that the worm may be transmitted locally to any mammalian host by chance. To investigate this notion, the ribosomal RNA gene (rDNA), mainly regions of the internal transcribed spacers (ITS) 1 and 2, and a cytochrome c oxidase subunit I (COI) region of mitochondrial DNA of G. pulchrum were characterized using parasites from the following hosts located in Japan: cattle, sika deer, wild boars, Japanese macaques, a feral Reeves's muntjac and captive squirrel monkeys. The rDNA nucleotide sequences of G. pulchrum were generally well conserved regardless of their host origin. However, a few insertions/deletions of nucleotides along with a few base substitutions in the ITS1 and ITS2 regions were observed in G. pulchrum from sika deer, wild boars and Japanese macaques, and those differed from G. pulchrum in cattle, the feral Reeves's muntjac and captive squirrel monkeys. The COI sequences of G. pulchrum were further divided into multiple haplotypes and two groups of haplotypes, i.e. those from a majority of sika deer, wild boars and Japanese macaques and those from cattle and zoo animals, were clearly differentiated. Our findings indicate that domestic and sylvatic transmission cycles of the gullet worm are currently present, at least in Japan.

Beta amyloid deposition and neurofibrillary tangles spontaneously occur in the brains of captive cheetahs (Acinonyx jubatus).

Alzheimer disease is a dementing disorder characterized pathologically by Aß deposition, neurofibrillary tangles, and neuronal loss. Although aged animals of many species spontaneously develop Aß deposits, only 2 species (chimpanzee and wolverine) have been reported to develop Aß deposits and neurofibrillary tangles in the same individual. Here, the authors demonstrate the spontaneous occurrence of Aß deposits and neurofibrillary tangles in captive cheetahs (Acinonyx jubatus). Among 22 cheetahs examined in this study, Aß deposits were observed in 13. Immunostaining (AT8) revealed abnormal intracellular tau immunoreactivity in 10 of the cheetahs with Aß deposits, and they were mainly distributed in the parahippocampal cortex and CA1 in a fashion similar to that in human patients with Alzheimer disease. Ultrastructurally, bundles of straight filaments filled the neuronal somata and axons, consistent with tangles. Interestingly, 2 of the cheetahs with the most severe abnormal tau immunoreactivity showed clinical cognitive dysfunction. The authors conclude that cheetahs spontaneously develop age-related neurodegenerative disease with pathologic changes similar to Alzheimer disease.

Cardiac angioleiomyoma in 44 cattle in Japan (1982-2009).

A retrospective study was performed on primary cardiac tumors found in 44 cattle during meat inspection in Japan, using histology, immunohistochemistry, and electron microscopy. The age of affected cattle ranged from 10 to 129 months; 82% were less than 3 years old. In 38 hearts, the tumor was solitary; the remaining 6 hearts had multiple masses. All tumors were subendocardial and involved the papillary muscles and/or cardiac valves. Two histologic patterns were recognized; both included giant cells. Pattern 1 was characterized by interlacing fascicles of spindle-shaped cells; pattern 2 resembled cavernous hemangioma. The 2 patterns coexisted and were linked by transitional zones. Given the immunohistochemical reactivity and ultrastructure, the spindle-shaped cells were identified as smooth muscle cells and the giant cells as endothelial cells. Single cell and multicellular angiogenesis by giant cells was observed. The tumors were classified as cardiac angioleiomyoma. Subendocardial multipotential mesenchymal cells, persistent tissue of the endocardial cushion, or valvular interstitial cells were suspected as the origin.

Contact dermatitis in dairy cattle caused by calcium cyanamide.

Nine of 250 cows on a dairy farm initially developed severe dermatitis on parts of their bodies that touched the floor, and it then spread over their entire body. The cause was suspected to be calcium cyanamide, which had been added to the material spread on the floor to prevent environmental mastitis. Experimental exposure of the skin of a cow to calcium cyanamide induced the same type of contact dermatitis, and histopathological investigations showed that it caused irritant and allergic reactions. To identify the cause of the dermatitis, a patch test with calcium cyanamide and its breakdown products, cyanamide, urea and ammonium bicarbonate, was carried out on four cows. Three of them had a positive reaction to calcium cyanamide and cyanamide; delayed and amplified reactions suggesting an allergic response were observed.

Spontaneous hepatic copper accumulation in Long-Evans Cinnamon rats with hereditary hepatitis. A model of Wilson's disease.

Long-Evans Cinnamon (LEC) rats, an inbred strain of a mutant rat isolated from Long-Evans rats, develop hereditary hepatitis. To elucidate the role of copper metabolism in the development of the hepatitis in LEC rats, we examined the copper concentration in the tissues and serum levels of copper and ceruloplasmin. Copper concentration in the liver of LEC rats was over 40 times that of normal Long-Evans Agouti (LEA) rats, while the serum ceruloplasmin and copper concentrations in LEC rats decreased significantly. The hepatocytes of LEC rats show steatosis in cytoplasm and pleomorphism of mitochondria, resembling the histologic features of the liver in Wilson's disease. These findings suggest that the hereditary hepatitis in LEC rats is closely associated with copper toxicity, and may be dealing with a rat form of Wilson's disease. Thus the LEC rats will provide a unique and useful animal model for clarifying the mechanism and for developing treatment strategies for Wilson's disease and other abnormal copper metabolism in humans.

Peracute Bacterial Meningitis due to Infection with Klebsiella pneumoniae in Captive-bred Ruffed Lemurs (Varecia variegate).

We describe the development of neurological signs in four juvenile black-and-white ruffed lemurs (Varecia variegate), housed at a petting zoo in Japan. The clinical course was severe, with three lemurs dying within 1 day of the appearance of clinical signs. The other lemur was treated and survived. Pathological analyses demonstrated meningitis and the presence of gram-negative bacilli in the cerebrum, cerebellum, palatine tonsil and liver. Klebsiella pneumoniae was isolated from the brain of all of the dead lemurs. Multilocus sequence typing analysis showed that all the isolates were sequence type 86 (ST86). To our knowledge, this is the first determination of K. pneumoniae infection in ruffed lemurs of this genus. K. pneumoniae infection may represent a risk to lemurs and people who come into contact with infected animals.

Fatal Salmonellosis in Captive Maras (Dolichotis patagonum) Caused by Salmonella Enteritidis.

We report epidemic occurrences of fatal salmonellosis caused by Salmonella Enteritidis in captive maras (Dolichotis patagonum) in a zoological garden in Japan. The deaths were sudden or followed a peracute course within a few hours of the first observations of clinical abnormalities. Gross lesions included haemorrhages in the subcutis and skeletal muscles, liver, spleen, lung, heart and gastrointestinal tract. Microscopically, there were haemorrhagic and necrotizing lesions with gram-negative bacilli in the liver, spleen, small intestine and Peyer's patches. These bacilli showed strong immunolabelling for Salmonella O9 antigen and S. Enteritidis was isolated from the lesions. To the best of our knowledge, this is the first report of salmonellosis in maras.

Prevalence of Baylisascaris Roundworm in Captive Kinkajous in Japan.

Baylisascaris potosis causes larva migrans in animals. The present study evaluated the prevalence of B. potosis in captive kinkajous ( Potos flavus ) and the ability of milbemycin to treat natural infections of B. potosis in 2 female wild-caught kinkajous. In 2012, fecal samples were collected from 16 kinkajous in 6 zoological gardens and 29 imported captive kinkajous from 4 pet traders in Japan. Although all samples from zoological gardens were negative, 8 kinkajous from traders were positive for Baylisascaris eggs, at least 4 of which were wild caught in the Republic of Guyana. No associated human illness was reported from any of the facilities. The 2 infected kinkajous received a single oral administration of Milbemycin® A Tablets, which delivers 0.69-0.89 mg/kg milbemycin oxime. Fecal examinations on days 14 and 30 were negative for Baylisascaris eggs. These results demonstrated that milbemycin oxime has possible anthelmintic efficacy against Baylisascaris roundworms in captive kinkajous. We conclude that Baylisascaris infections are highly prevalent in wild-caught kinkajous in Japan and that most of the infected kinkajous were imported from the Republic of Guyana.

Experimental infection of Mongolian gerbils with Baylisascaris potosis.

The present study evaluated the pathogenicity of Baylisascaris potosis, a newly described ascarid nematode, in Mongolian gerbils. Gerbils were infected with varying doses of either B. potosis or Baylisascaris transfuga embryonated eggs (100, 1,000, and 4,000) for 30 days postinfection (pi). Baylisascaris potosis-infected gerbils showed no clinical signs of disease; however, gerbils exposed to 1,000 and 4,000 B. transfuga eggs showed severe neurologic signs at 22-29 days and 14-15 days pi, respectively. Histopathologic examination revealed larvae and lesions in the intestine, lung, liver, and muscles of B. potosis-infected gerbils, but not in the brain, whereas B. transfuga larvae were found only in the brain and muscle. These results indicate that B. potosis larvae migrate through numerous organs and are associated with visceral larva migrans in gerbils, but less frequently migrate to the nervous system in gerbils than does B. transfuga .

Serum levels of the type IV collagen 7s domain in patients with chronic viral liver diseases.

The serum levels of type IV collagen 7s domain (7s collagen) were determined in 80 patients with hepatocellular carcinoma (HCC) and in 105 with chronic liver disease without HCC. Among 86 patients with HCV infection, serum levels of the 7s collagen were significantly higher in those with HCC than-in those without HCC (p<0.05). In contrast, no significant differences were recognized between these two groups in 84 patients with HBV infection. Patients with HCV infection having high serum levels of the 7s collagen exceeding 7.0 ng/ml, were diagnosed as HCC with a sensitivity of 71.8%, a specificity of 74.5%, and a reliability of 77.9%. It was concluded that the progression of hepatic fibrosis plays an important role in the hepatocarcinogenesis of HCV, and that serum levels of the 7s collagen appeared to be useful as a risk factor of the development of HCV-related HCC.

Hepatocyte growth factor enhances the invasion activity of human hepatocellular carcinoma cell lines.

We investigated whether hepatocyte growth factor (HGF) enhances the invasion activity of three human HCC cell lines, HLF, HLE, and HC-4, in vitro. The analysis of the invasiveness consisted of the production of u-PA and the chemotaxis for fibronectin. Invasion activity of all cell lines was enhanced by the addition of recombinant human hepatocyte growth factor (rhHGF) to the medium. HGF stimulated the production of u-PA in HLF cells. HGF accelerated the chemotaxis of HC-4 and HLE. These data suggest that HGF increase the invasion activity of human HCC cell lines by affecting the production of u-PA or the chemotaxis for fibronectin.

Expression of sex-hormone receptors and clinicopathological findings in hepatocellular-carcinoma.

We studied the expresssion of estrogen (ER), progesterone (PgR), and androgen receptors (AR) in hepatocellular carcinoma (HCC) and found expression in (7/36), 3.2% (1/31), 16.7% (4/24) of cases, respectively. The expression of ER did not correlate with histological grade, tumor size, or stage of disease. On the other hand, all the patients with AR-positive tumors had stage IV disease, and only 25% of the patients with AR-negative tumors had stage IV disease. The survival was not influenced by the expression pattern of ER, however, the survival of the patients with AR-positive tumors tended to be worse than that of patients with AR-negative tumors. We suggest that the AR expression correlates better with poor outcome in HCC than the ER expression.

HLA class I antigens are possible prognostic factors in hepatocellular carcinoma.

Thirty patients who underwent hepatectomy for the treatment of hepatocellular carcinoma (HCC) were examined for expression of HLA class I antigens on HCC cells by flow cytometry. The expression was found significantly lower in cases of stage IV compared with those of stage I or stage II (p<0.05), and in cases of intrahepatic metastases compared with those without metastases (p<0.001). In cases of non-curative hepatectomy, the expression of HLA class I antigens was lower compared with those treated by curative resection. Postoperative cumulative disease-free survival rates were well correlated with the expression rate of HLA class I antigens (p<0.05). Expression of HLA class I antigens on HCC may indicate low malignancy and better prognosis.

Prediction of prognosis after resection in human hepatomas by nuclear-DNA analysis.

Nuclear DNA analysis with flow cytometry was performed in 81 patients with hepatocellular carcinoma. Thirty-eight cases (46.9%) were diploid type and forty-three cases (53.1%) aneuploid type. Microscopical portal vein invasion of the tumor was more frequent in the aneuploid group (p<0.05). Significantly higher frequency of intrahepatic metastasis was found in the aneuploid group (p<0.05). There was no correlation between the tumor nucleus DNA ploidy pattern and the recurrence rate, 23 (60.5%) of diploid cases and 28 (65.1%) of aneuploid cases, respectively. Disseminated recurrence was more frequent in the aneuploid group than in the diploid group (p<0.10). Significantly better survival rates were observed in the diploid group which had microscopical portal invasion. Moreover, the diploid group which had no capsular formation and intrahepatic metastasis showed significantly longer survival terms.

Preoperative prediction of postoperative reserve hepatic function for liver surgery for hepatobiliary, pancreatic cancer.

To perform safer hepatic resection for hepatobiliary-pancreatic cancer, the possibility of preoperative prediction of postoperative reserve hepatic function was assessed using hepatobiliary scintigraphy. After intravenous administration of Tc-99m-pyridoxyl-5-methyltryptophan in 23 patients, the time-activity curves of region of interest over the heart and liver were generated, and peak and one-fourth clearance times were calculated, which were compared with biochemical data. The parameters were significantly related to protein syntheses (prothrombine time and hepaplastin test) and indocyanine-green dye excretion, but not to hepatobiliary enzymes. So we hypothesized 'when the curve left by subtracting the resected area from the whole liver was larger than one-third of the total liver curve, the surgery would be safe', which we applied to another eight patients, clarifying the hypothesis. Hepatobiliary scintigraphy can be a promising procedure in the assessment of partial liver function, and the study will contribute to a safer liver surgery.

Effects of hyperthermia on multidrug-resistant human hepatocellular-carcinoma.

The effects of hyperthermia (HT) on multidrug-resistant human hepatocellular carcinoma (HCC) were evaluated experimentally. This tumor, an AFP-producing human HCC, in which MDR1 mRNA and P-glycoprotein were overexpressed, was transplanted subsequently on nude mice. Ten days after the inoculation of the tumor into the rear section of the nude mice, either or both an intra-peritoneal injection of 8 mg/kg of adriamycin (ADR) was administered or hyperthermia (HT) was induced. HT was performed immediately by immersing the mice into a water bath at a temperature of 42-degrees-C for a period of 30 minutes. Hyperthermic therapy combined with ADR significantly inhibited the tumor growth compared with ADR or HT alone. Using ADR in combination with HT, the ADR concentration in the tumor remained at a significantly higher level for a prolonged period compared with ADR alone. The results indicate that HT enhanced the anti-tumor effect of chemotherapy even for multidrug-resistant HCC.

Efficacy and safety of preoperative percutaneous transhepatic portal embolization with absolute ethanol: a clinical study.

BACKGROUND: Preoperative portal embolization has been performed by using various thrombogenic substances to increase the safety and resectability of liver surgery. We evaluated the clinical safety and efficacy of using absolute ethanol in preoperative portal embolization. METHODS: Our study included 19 patients who had undergone right hepatic lobectomy. According to our criteria for right lobectomy of the liver, seven patients were not appropriate for the operation because of a high risk in each of postoperative liver failure. Those patients received preoperative right portal embolization with 11 to 32 ml absolute ethanol. The remaining 12 patients satisfied our criteria and received no preoperative embolization. RESULTS: Although alanine aminotransferase concentrations increased dramatically after the embolization, all serologic changes reverted within 3 weeks. The mean volume of the nonembolized lobe increased from 320 cm3 to 619 cm3 and 667 cm3 2 and 4 weeks, respectively, after embolization. The mean regeneration rate of this lobe was 21.3 cm3 per day for the first 2 weeks and 11.4 cm3 per day for the first 4 weeks after embolization. All patients underwent right lobectomy of the liver and survived; none of the patients had severe complications associated with embolization or surgery. The postoperative survival periods were not statistically significant between the patients with and without preoperative portal embolization. CONCLUSIONS: According to our criteria for liver surgery, the seven patients should not have undergone major surgery, but each underwent right lobectomy of the liver and all survived, showing that portal embolization with absolute ethanol brings about compensatory hepatic hypertrophy for major surgery and that its extreme effect on liver regeneration could widen the range of patients appropriate for liver surgery.