Mechanism of long-term high-dose prednisolone administration producing myocardial fibrosis in beagle dogs.

Background: We previously reported that myocardial fibrosis may be one of the causes of left ventricular hypertrophy and cardiac dysfunction in dogs with hyperglucocorticism (HGC). The detailed mechanism by which myocardial fibrosis of the left ventricle occurs in dogs with HGC remains unclear.

Aim: Th is study investigated the mechanism by which HGC causes fibrosis of the left ventricle.

Histamine deficiency inhibits lymphocyte infiltration in the submandibular gland of aged mice via increased anti-aging factor Klotho.

Objectives: Histidine decarboxylase (HDC), a histamine synthase, is expressed in various tissues and is induced by proinflammatory cytokines such as TNFα. As they age, C57BL/6 mice show auto-antibody deposition and lymphocyte infiltration into various tissues, including salivary glands. However, the mechanism underlying cell infiltration and the change in HDC expression in salivary glands with aging remain unclear.

Expression of type VI collagen α3 chain in canine mammary carcinomas.

This study aimed to investigate the expression of type VI collagen α3 chain (COL6a3) in neoplastic cells of canine mammary gland carcinomas (CMGCs) using immunohistochemistry (IHC) and to evaluate the association between COL6a3 expression and tumor histological features, histological grades, and the differentiation status of neoplastic epithelial cells. COL6a3 expression in carcinoma cells was significantly associated with histologically low malignancy and low mitotic indices. In addition, COL6a3+ carcinoma cells were more frequently detected in simple carcinomas (tubular and tubulopapillary types) than in solid carcinomas.

Long-term histological effects of high-dose prednisolone administration on the mitral valve in normal Beagle dogs.

Background: In recent years, left ventricular hypertrophy and cardiac dysfunction have been reported in human and canine patients with hypercortisolism and in dogs treated experimentally with high-dose prednisolone. However, to our knowledge, there have been no reports on the effects of hyperglucocorticism (HGC) on the mitral valve (MV).

Aim: This study aimed to compare the MV in dogs treated with high-dose prednisolone with that in healthy dogs to investigate the effects of HGC on the MV.

Expression of receptor-type tumour endothelial marker 8 in carcinoma cells showing luminal progenitor-like phenotypes in canine mammary gland carcinomas.

This study aimed to investigate the expression of receptor-type tumour endothelial marker 8 (TEM8RT) in canine mammary gland carcinomas (CMGCs) using immunohistochemistry and to evaluate the association between carcinoma cell TEM8RT expression and tumour histological features, histological grades and the differentiation status of neoplastic epithelial cells. TEM8RT expression was more frequently detected in simple carcinomas (tubular and tubulopapillary) than in solid carcinomas, and it was significantly correlated with histological grade Ⅰ tumours and a low mitotic index. Additionally, TEM8RT carcinoma cells were more frequently found in CMGCs showing luminal progenitor-like phenotypes, such as Notch1, CK19/CK5/CD49f and CK19/CK5/CD49f.

Adrenocorticotropic hormone-producing pituitary adenoma with pituitary apoplexy treated by surgical decompression: a case report.

Background: Pituitary-dependent hypercortisolism (PDH) is one of the most common endocrine disorders in veterinary medicine. However, there are few reports on pituitary tumor apoplexy (PTA) in dogs and no reports on its surgical intervention in veterinary medicine. Accordingly, the appropriate treatment is unknown.

Influence of ventral fixation techniques on atlantoaxial joint fusion in canine models with dens partial resection.

We evaluated the completeness of bony fusion of the atlantoaxial joint (AAJ) through polymethylmethacrylate fixation (PMF) and atlantoaxial plate fixation (APF) using six canine models with dens partial resection. In both groups, the hydroxyapatite content at the AAJ was measured up to 7 months postoperatively using quantitative computed tomography. Histological assessment revealed fibrous fusion in the PMF group.

Histidine decarboxylase deficiency inhibits NBP-induced extramedullary hematopoiesis by modifying bone marrow and spleen microenvironments.

Histidine decarboxylase (HDC), a histamine synthase, is expressed in various hematopoietic cells and is induced by hematopoietic cytokines such as granulocyte colony-stimulating factor (G-CSF). We previously showed that nitrogen-containing bisphosphonate (NBP)-treatment induces extramedullary hematopoiesis via G-CSF stimulation. However, the function of HDC in NBP-induced medullary and extramedullary hematopoiesis remains unclear.

Long-term administration of prednisolone: Effects on the myocardial tissue of healthy beagle dogs.

This study aimed to assess the structural and functional effects of long-term hyperglucocorticoidemia on canine myocardium and compare these parameters with histopathological changes. Twelve healthy male beagle dogs were enrolled and assigned to the high-dose prednisolone (P; n=6) and control (C; n=6) groups. The P group was treated with 2 mg/kg of prednisolone BID for 84 days.

Changes in histidine decarboxylase expression influence extramedullary hematopoiesis in postnatal mice.

Histidine decarboxylase (HDC), histamine synthase, is expressed in hematopoietic stem cells and in lineage-committed progenitors in the bone marrow (BM). However, the role of histamine in hematopoiesis is not well described. To evaluate the role of histamine in hematopoiesis, we analyzed the changes in HDC expression at hematopoietic sites, the BM, spleen, and liver of 2-, 3-, and 6-week-old wild-type mice.

Expressions of vascular endothelial growth factor receptors, Flk1 and Flt1, in rat skin mast cells during development.

Vascular endothelial growth factor-A (VEGF-A) is a principal regulator of hematopoiesis as well as angiogenesis. However, the functions of VEGF-A and its receptors (VEGFRs) in the differentiation of mast cells (MCs) in the skin remain unclear. The aim of this study was to determine the expression patterns of two VEGFRs (Flk1 and Flt1) in the skin MCs during development and maturation in rats.

Big Insulin-like Growth Factor 2-Producing Tumor in a Hypoglycemic Dog.

A 10-year-old female Papillon dog that had previously developed a mammary tumor was admitted for treatment of a hypoglycemic attack. Blood examination showed severe hypoglycemia and decreased blood insulin concentration. Computed tomography indicated multiple tumors in the cranial and caudal lobes of the right lung.

Multivariate analysis of variations in intrinsic foot musculature among hominoids.

Comparative analysis of the foot muscle architecture among extant great apes is important for understanding the evolution of the human foot and, hence, human habitual bipedal walking. However, to our knowledge, there is no previous report of a quantitative comparison of hominoid intrinsic foot muscle dimensions. In the present study, we quantitatively compared muscle dimensions of the hominoid foot by means of multivariate analysis.

Nitrogen-containing bisphosphonate induces a newly discovered hematopoietic structure in the omentum of an anemic mouse model by stimulating G-CSF production.

We previously reported that the injection of nitrogen-containing bisphosphonate (NBP) induced the site of erythropoiesis to shift from the bone marrow (BM) to the spleen. Our previous study established a severely anemic mouse model that was treated with a combination of NBP with phenylhydrazine (PHZ), which induced newly discovered hematopoietic organs in the omentum. No reports have shown that new hematopoietic organs form under any condition.

Polyglucosan Bodies in the Prostatic Stromal Smooth Muscles of Aged Dogs.

Polyglucosan bodies (PGB) in the prostate of aged dogs without neurological signs were examined by light microscopy, histochemistry and immunohistochemistry. Prostatic PGB were round or oval and slightly basophilic. Most of the bodies were situated within the stromal smooth muscle cells.

Escherichia coli-derived recombinant human bone morphogenetic protein-2 combined with bone marrow-derived mesenchymal stromal cells improves bone regeneration in canine segmental ulnar defects.

Background: Large bone defects in canines usually require assistance to achieve healing. Implantation of osteoinductive factors can promote bone healing, while transplantation of osteoprogenitor cells can enhance bone regeneration. We hypothesized that implantation of an osteoinductive factor, recombinant human bone morphogenetic protein-2 (rhBMP-2), combined with osteoprogenitor cells, bone marrow-derived mesenchymal stromal cells (BMSCs), would synergistically promote bone healing.

Distribution of type VI collagen in association with osteoblast lineages in the groove of Ranvier during rat postnatal development.

In the groove of Ranvier (GOR), osteoblast lineages form bone bark, which develops into endosteal cortical bone. This ossification process is thought to be regulated by the microenvironment in the GOR. Type VI collagen (Col VI), an extracellular matrix (ECM) protein found in the periosteum/perichondrium, mediates osteoblast differentiation via the cell-surface receptor neural/glial antigen 2 (NG2) chondroitin sulfate proteoglycan.

The expression of embryonic globin mRNA in a severely anemic mouse model induced by treatment with nitrogen-containing bisphosphonate.

Background: Mammalian erythropoiesis can be divided into two distinct types, primitive and definitive, in which new cells are derived from the yolk sac and hematopoietic stem cells, respectively. Primitive erythropoiesis occurs within a restricted period during embryogenesis. Primitive erythrocytes remain nucleated, and their hemoglobins are different from those in definitive erythrocytes.

A Comparison of the Process of Remodeling of Hydroxyapatite/Poly-D/L-Lactide and Beta-Tricalcium Phosphate in a Loading Site.

Currently, the most commonly used bioresorbable scaffold is made of beta-tricalcium phosphate (β-TCP); it is hoped that scaffolds made of a mixture of hydroxyapatite (HA) and poly-D/L-lactide (PDLLA) will be able to act as novel bioresorbable scaffolds. The aim of this study was to evaluate the utility of a HA/PDLLA scaffold compared to β-TCP, at a loading site. Dogs underwent surgery to replace a section of tibial bone with a bioresorbable scaffold.

Accumulation of type VI collagen in the primary osteon of the rat femur during postnatal development.

In rodents, the long bone diaphysis is expanded by forming primary osteons at the periosteal surface of the cortical bone. This ossification process is thought to be regulated by the microenvironment in the periosteum. Type VI collagen (Col VI), a component of the extracellular matrix (ECM) in the periosteum, is involved in osteoblast differentiation at early stages.

Degenerative changes of the cranial cruciate ligament harvested from dogs with cranial cruciate ligament rupture.

Degenerative cranial cruciate ligament (CCL) rupture is characterized histologically by degenerating extracellular matrix (ECM) and chondroid metaplasia. Here, we describe the progression of chondroid metaplasia and the changes in the expression of ECM components in canine CCL rupture (CCLR). CCLs from 26 stifle joints with CCLR (CCLR group) and normal CCLs from 12 young beagles (control group) were examined histologically and immunohistochemically for expression of type I (COLI), type II (COLII), type III collagen (COLIII) and Sry-type HMG box 9 (SOX9).

Conjunctival expression of the P2Y2 receptor and the effects of 3% diquafosol ophthalmic solution in dogs.

Conjunctival epithelial and goblet cell P2Y2 nucleotide receptors regulate ion transport and secretory function. Diquafosol is a P2Y2 purinergic receptor agonist that stimulates secretion of aqueous tear components from conjunctival epithelial cells and secretion of mucin from conjunctival goblet cells. In humans suffering from keratoconjunctivitis sicca (dry eye), topical administration of diquafosol improves corneal epithelial integrity and stabilises the tear film.

Molecular characterization and tissue distribution of feline retinol-binding protein 4.

Retinol-binding protein 4 (RBP4) is a specific transporter of retinol and was recently identified as an adipokine potentially involved in type 2 diabetes in humans and rodents. However, the function and structure of feline RBP4 have not been reported. In this study, we describe the molecular cloning and expression analysis of feline RBP4.

Preliminary immunohistochemical study of natriuretic peptide receptor localization in canine and feline heart.

We examined the immunohistochemical distributions of natriuretic peptide receptor (NPR)-A, -B and -C that bind with natriuretic peptide hormones A, B and C in four healthy crossbreed young canine and feline cardiac tissues using specific antibodies against human antigens. Cross-immunoreactivities between antigens and antibodies were confirmed using western blot analysis. NPR-A and -C were expressed more strongly in dogs than cats.