Evaluation of serum and urine 1,5-anhydro-D-glucitol and myo-inositol concentrations in healthy dogs

1,5-anhydro-D-glucitol (1,5AG) is a pyranoid polyol compound found in human circulating blood. Myo-inositol (MI) is a stereoisomer of inositol and serves as a precursor of inositol phospholipids. 1,5AG and MI are filtered by the glomerulus and almost completely reabsorbed through the renal tubules. However, under hyperglycemic conditions, reabsorption through the renal tubules is competitively inhibited because the structures of 1,5AG and MI resemble that of glucose. In this study, we investigated the kinetics of serum and urine 1,5AG and MI levels in healthy dogs. We demonstrated that 1,5AG and MI exist in canine serum and urine by gas chromatography-mass spectrometry. Under continuous hyperglycemic conditions, the serum 1,5AG concentration in healthy dogs decreased while the serum MI concentration remained unchanged. Urinary excretion of 1,5AG and MI increased significantly after blood glucose concentrations reached 200 to 220 mg/dl. A significant negative correlation was observed between serum 1,5AG and glucose concentrations during hyperglycemia. However, no significant correlation was observed between serum MI and glucose concentrations. In this study, we demonstrated that serum and urine 1,5AG and MI levels were changed by blood glucose concentrations. The serum 1,5AG concentration was decreased by continuous hyperglycemia. However, the serum MI concentration does not reflect hyperglycemia.     

Effect of calcitonin on adrenocorticotropic hormone secretion stimulated by corticotropin‐releasing hormone in the hen anterior pituitary

The presence of a receptor for calcitonin (CT) and the effect of chicken CT (cCT) on adrenocorticotropic hormone (ACTH) secretion stimulated by rat/human corticotropin‐releasing hormone (rhCRH) in the hen anterior pituitary were studied. The specific [¹²⁵I]cCT binding component was present in the plasma membrane of hen anterior pituitary and this binding component had properties of a receptor which has binding specificity to cCT, reversibility, saturable binding, high affinity and limited capacity. When anterior pituitary cells were incubated in vitro, cCT increased the maximal secretion of chicken ACTH stimulated by rhCRH. These results suggest that CT may act directly on the anterior pituitary via its receptor binding and enhances the ACTH secretion by CRH.     

Analysis of chromosome-sized DNA and genome typing of isolated strains ofTaylorella equigenitalis

Analysis of chromosome-sized DNA and genome typing ofTaylorella equigenitalis NCTC11184, Kentucky 188, and five strains ofT. equigenitalis isolated in Japan were carried out. The three restriction enzymes used,ApaI,NaeI andNotI, cleaved the genomic DNAs of five Japanese strains ofT. equigenitalis into relatively limited numbers of restriction fragments, which were well resolved on crossed-field gel electrophoresis (CFGE). The respective profiles after CFGE of the restriction fragments from all five strains were essentially identical to each other after digestion byApaI,NaeI orNotI. Hence it appears that these strains have a common genome type with respect to these three restriction enzymes. It was also shown that the respective profiles from these strains were essentially different from those ofT. equigenitalis NCTC11184 and those of Kentucky 188 after digestion withApaI,NaeI orNotI.Abbreviations CFGE crossed-field gel electrophoresis - FIGE field inversion gel electrophoresis - PFGE pulsed-field gel electrophoresis     

Histopathological characteristics of Kupffer cells and ito cells in the porcine and bovine liver

We previously reported that no Kupffer cells reacted with the antibody against lysozyme, and Ito cells contained a large cytoplasmic vacuole in the feline liver. In this report, we further examined the characteristics of porcine and bovine hepatic non-parenchymal cells. In the liver of both animals, Kupffer cells were positive for lysozyme, and cytoplasmic vacuoles in Ito cells were small. The histopathological characteristics of porcine and bovine hepatic non-parenchymal cells were different from those of the feline liver.     

A retrospective study and gene analysis of canine sterile panniculitis

In this study, a retrospective analysis was conducted to assess the current aspects and predisposing factors of canine sterile panniculitis. Miniature dachshund, neutered, and younger dogs appeared to be predisposed. In addition, histories of previous surgery and injection were associated in 46.5% of the cases, with several types of surgical suture materials used. About 88% of the dogs had multifocal lesions, frequently with signs of systemic illnesses. Whereas systemic immunosuppressive therapy was effective in most dogs, surgical excision of lesions was rarely curative. In order to prevent recurrences, over 65% of the cases required prolonged immunosuppressive therapy. Polymorphism of canine alpha(1)AT gene was investigated as a candidate gene for sterile panniculitis. Eight polymorphisms were discovered in seven Miniature dachshunds by direct nucleotide sequencing, which included a 12-bp deletion, three non-synonymous single nucleotide polymorphisms, and four silent substitutions. Genotyping of the two polymorphisms, c.109_120del12 and c.483A>C, which identified at high incidence in the dachshunds, was conducted in 83 dogs of 6 popular breeds. The frequencies of neither polymorphism differed between Miniature dachshunds and other breeds, suggesting that neither is responsible for developing panniculitis.     

Colitis associated with Clostridium difficile in specific-pathogen-free C3H-scid mice

Soft feces and a decreased delivery rate were observed in a specific-pathogen-free (SPF) C3H-scid mouse breeding colony. Grossly, the ceca were shrunken and edematous in the affected mice. Histopathologically, severe edema in the cecal submucosa as well as infiltration of inflammatory cells in the lamina propria and submucosa of the ceca and colon were observed. No pathogenic microorganisms were detected by the routine microbiological tests. By anaerobic bacterial-examination, Clostridium (C.) difficile with toxin A was isolated from the cecal contents of the affected mice. The mice were diagnosed with C. difficile-associated colitis. This case appears to be the first report of natural infection with C. difficile in SPF mice with clinical signs.     

Changes in the muscle fibre properties of the mouse temporal muscle after weaning

To clarify changes in the muscle fibre properties of the temporal muscle related to the start of masticatory movement, we immunohistochemically investigated myosin heavy chain (MyHC) isoform protein expression using pre-weaning and post-weaning mice. In addition, we examined the expression of a gene coding for those MyHC proteins. Immediately after weaning, isoforms with fast and potent contractility were frequent. This suggests that the temporal muscle plays an important role in a marked functional change in the oral cavity from lactation to mastication, contributing to oral function in cooperation with other masticatory muscles.     

Serological differentiation of FIV-infected cats from dual-subtype feline immunodeficiency virus vaccine (Fel-O-Vax FIV) inoculated cats

Feline immunodeficiency virus (FIV) vaccine, Fel-O-Vax FIV, was released for sale in the US in 2002. The antibodies of vaccinated cats interfere with serological assays by currently available FIV diagnostic kits. In this study, we investigated whether it is possible to distinguish serologically cats vaccinated with Fel-O-Vax FIV from cats experimentally or naturally infected with FIV. A total of 153 sera taken from 97 cats were used as serum samples. Enzyme linked immunosorbent assay (ELISA) was performed using whole FIV antigen and formalin treated whole FIV antigen, recombinant-gag (r-gag) antigen, and transmembrane (TM) peptide. Statistical analysis was performed using ELISA optical density (O.D.) values obtained with each antigen as variables. Except for the ELISA O.D. values obtained with r-gag antigen, a significant difference in ELISA O.D. values was observed between the vaccinated and the infected groups. However, it was not possible to distinguish both groups unequivocally. Using discriminant analysis, it was possible to distinguish the two groups with an accuracy of 97.1% with two discriminating variables (ELISA O.D. values obtained with formalin treated whole FIV antigen, and TM peptide), 97.8% with three discriminating variables (ELISA O.D. values obtained with whole FIV antigen, formalin treated whole FIV antigen, and TM peptide). Therefore, it was considered possible to distinguish cats vaccinated with Fel-O-Vax FIV from FIV-infected cats by ELISA using two types of antigens including formalin treated whole FIV antigen and TM peptide, or three types of antigens including formalin treated whole FIV antigen, TM peptide and whole FIV antigen.     

Induction of chemoresistance in a cultured canine cell line by retroviral transduction of the canine multidrug resistance 1 gene

OBJECTIVE: To induce chemoresistance in a normal canine cell line through the transduction of the canine multidrug resistance 1 gene (mdr1). SAMPLE POPULATION: Madin-Darby canine kidney (MDCK) epithelial cell line. PROCEDURES: The full-length canine mdr1 cDNA clone isolated in our laboratory was inserted into a Moloney murine leukemia virus-based vector to construct the retroviral vector, pLNC-cMDR1. After retroviral transduction of pLNC-cMDR1 into MDCK cells, the expression and function of the P-glycoprotein, a product of mdr1, were assessed by immunoblotting, measurement of rhodamine123 (Rh123) retention, and drug sensitivity assays. RESULTS: P-glycoprotein was strongly expressed in cells transduced with pLNC-cMDR1. This P-glycoprotein was fully functional, as demonstrated by the decreased Rh123 retention and the increased resistance to chemotherapeutic drugs. Measured as 50% inhibitory concentrations, resistance increased 59 times to vincristine and 25 times to doxorubicin in MDCK cells after transduction of pLNC-cMDR1. CONCLUSIONS AND CLINICAL RELEVANCE: Transduction of canine mdr1 is an effective method for inducing chemoresistance in normal canine cells. This system may be applicable to the induction of drug resistance in hematopoietic cells.