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A male 25-month-old Dalmatian dog attended our veterinary hospital because of anorexia and high circulating liver enzyme activities. Abdominal computed tomography showed a slightly small liver with rounded edges, and laparoscopic examination showed that the liver was yellowish. Histopathological examination revealed multifocal necrosis of hepatocytes and severe chronic hepatitis. Rhodanine staining showed severe copper accumulation in hepatocytes and a quantitative analysis of the copper content of the liver showed substantial accumulation (10.3 mg/g dry mass), suggesting a diagnosis of copper-associated hepatitis. Previously reported canine mutation in the COMMD1, the gene responsible for the copper-associated hepatitis in the Bedlington terrier, was not identified. To our knowledge, this is the first report of copper-associated hepatitis in a Dalmatian in Japan.

Background: For optimal treatment, it is important to maintain optimal multi-leaf collimator (MLC) transmission in intensity-modulated radiation therapy (IMRT). However, adjustment of transmissions has not been reported in veterinary medicine. Aim: To demonstrate that appropriate MLC parameter adjustment for IMRT using 4- and 6-MV energy can reduce the need for quality assurance revalidation in real companion animal clinical cases. Methods: The MLC parameters (leaf transmission and leaf offset) of the treatment planning system were adjusted by evaluating seven plans (10 × 10 cm, 3ABUT, DMLC, 7segA, FOURL, HDMLC, and HIMRT) and 20 preclinical cases (10 cases each in 4- and 6-MV groups). Subsequently, 101 IMRT plans of 88 cases (77 dogs and 11 cats) were evaluated for absolute dose of plan target volume (PTV) and organs at risk (OAR) and were analyzed for the relative dose distribution by gamma analysis (3%/3 mm, >10%) using EBT3 film. Results: After adjustment of the MLC parameters (leaf transmission and leaf offset, 4 MV: 0.008 and 0, 6 MV: 0.005 and 0, respectively), the data from 101 plans (4 MV: 64 plans and 6 MV: 37 plans) treated with IMRT showed PTV

Adipose-derived stem cells (ADSCs) are promising cell sources for regenerative medicine due to the simplicity of their harvest and culture; however, their biological properties are not completely understood. Moreover, recent murine and human studies identified several functional subpopulations of ADSCs varying in differentiation potential; however, there is a lack of research on canine ADSCs. Cystine transporter (xCT) is a stem cell marker in gastric and colon cancers that interacts with CD44 to enhance cystine uptake from the cell surface and subsequently accelerates intercellular glutathione levels. In this study, we identified a ~5% functional subpopulation of canine ADSCs with xCT+ expression (xCTHi). Compared with those of the xCT− subpopulation (xCTLo), the xCTHi subpopulation showed a significantly higher proliferation rate, higher expression of conventional stem cell markers (SOX2, KLF4, and c-Myc), and higher expression of adipogenic markers (FABP4 and PPARγ). By contrast, the xCTLo subpopulation showed significantly higher expression of osteogenic markers (BMP1 and SPP) than xCTHi cells. These results suggest xCT as a candidate marker for detecting a functional subpopulation of canine ADSCs. Mechanistically, xCT could increase the adipogenic potential while decreasing the osteogenic differentiation potential, which could serve as a valuable target marker in regenerative veterinary medicine.

Transcatheter arterial embolization (TAE) and transcatheter arterial chemoembolization (TACE) are standard treatments for advanced hepatocellular carcinoma (HCC) and particularly for unresectable tumors or liver metastases in humans. However, reports on TACE used in veterinary medicine are few. This study aimed to evaluate the feasibility and safety of drug-eluting bead transarterial chemoembolization (DEB-TACE). We performed DEB-TACE in four clinically normal dogs and pharmacokinetically compared the results against hepatic arterial infusion (HAI) of cisplatin in two dogs. Drug-eluting beads (DEB) loaded with cisplatin were injected through a microcatheter for selective embolization of the left hepatic artery. After embolization, computed tomography (CT) images and histological examination findings were obtained during a 4-week observation period. Serum platinum concentrations were measured to evaluate cisplatin after each procedure. Biochemical analysis was performed during a 12-week observation period. Embolization was successful in all dogs, and there were no clinically apparent abnormalities. Embolization was confirmed up to 4 weeks after DEB-TACE in two of the four dogs and up to 1 week in the other two dogs using postoperative CT images. Cisplatin was not detected in peripheral veins in all dogs after DEB-TACE, but it was detected in trace amounts after HAI. DEB-TACE using cisplatin was safe and well tolerated by normal dogs. DEB-TACE may be useful in terms of determining systemic toxicity and drug concentration within tumors.

An 11-year-old male toy poodle with neurological symptoms was diagnosed with a macroscopic pituitary tumor, which produced adrenocorticotropic hormone. Radiation therapy with a linear accelerator was performed for the pituitary tumor, and resulted in good local tumor control. However, serum endogenous adrenocorticotropic hormone concentrations were uncontrollable even after the tumor disappeared. Abdominal computed tomography revealed splenic masses, and splenectomy was performed. Histopathological examination of the surgical specimen showed tumor cells with eosinophilic and finely granular cytoplasm suggestive of endocrine origin. Since these cells were positive for adrenocorticotropic hormone, the case was diagnosed as a pituitary carcinoma with distant metastasis. Necropsy revealed multiple metastases to the abdominal organs. This is the first case report describing canine pituitary carcinoma with distant metastasis.

Hepatocellular carcinoma (HCC) is the most common type of canine primary liver tumor; however, most chemotherapies against HCC are ineffective due to resistance to anticancer agents. Sphere-forming cells are considered to act as cancer stem cells for various types of solid tumors and have been established for many canine tumor cell lines, yet no studies have reported sphere-forming cells for canine HCC. In this study, we established sphere-forming cells from a canine HCC cell line (AZACH). These cells displayed increased stem cell marker mRNA expression (Nanog, Sox2, c-Myc, and Klf4), aldehyde dehydrogenase activity, and chemoresistance against mitoxantrone, gemcitabine, and doxorubicin. In addition, sphere-forming cells exhibited higher xCT expression and lower intracellular reactive oxygen species levels than adherent cells. Treatment with sulfasalazine, a xCT-specific inhibitor, reduced sphere formation efficiency. Together, these results indicate that sphere-forming cells derived from a canine HCC cell line have similar characteristics to cancer stem cells and that their increased xCT expression and associated resistance to oxidative stress contribute toward sphere formation.

Background: Radiation therapy is considered important for the treatment of intranasal tumors in dogs and is believed to be essential for prolonging their survival. Aim: We investigated the contribution of clinical staging to improving outcomes of megavoltage radiotherapy for canine intranasal tumors. Methods: A total of 123 dogs with intranasal tumors were included in the study. Forty-eight dogs received orthovoltage radiotherapy after cytoreductive surgery (Group I), 21 received orthovoltage radiotherapy without surgery (Group II), and 54 received megavoltage radiotherapy without surgery (Groupe III). All cases in each group were classified into clinical stages 1–4, and the median survival time (MST) was compared for each stage in all groups. Results: The overall MST was not significantly difference among Group I (325 days), Group II (317 days) and Group III (488 days), however, the Group III was prolonged than Groupe I and II. The MSTs for stages 1, 2, 3 and 4 were 597, 361, 267 and 325 days in Group I, and 633, 260, 233 and 329 days in Group II, and 931, 860, 368 and 176 days in Group III, respectively. The MST for stage 2 cases in Group III was significantly prolonged when compared with that in Group I and II; no significant difference was observed at other stages, however, the MST in Group III was longer in stage 1. These results showed that megavoltage radiotherapy prolonged the MST in dogs with intranasal tumors when compared to orthovoltage radiation with or without cytoreductive surgery, and that improvements in MST at stage 2 contributed significantly to this. Conclusion: The improvement in the MST in dogs with stages 1 and 2 intranasal tumors highlights the importance of starting megavoltage radiotherapy in the early stages.

The effect of selective transcatheter arterial embolisation (TAE) using trisacryl gelatine microspheres (TGMs) in the normal canine liver was investigated. Selective embolisation was achieved by injecting TGMs into the left hepatic artery through a microcatheter in four healthy dogs. After embolisation, computed tomography (CT), biochemical analysis and histological examination were performed during a 12-week observation period. Embolisation was successful in all four dogs. Postoperative CT revealed consistent embolisation of the artery within the experimental period in three dogs. Hepatic enzyme levels slightly increased after embolisation but tapered to normal ranges. Histological examinations revealed no abnormal changes. Thus, selective TAE with TGMs was well tolerated in normal dogs and may be applicable to canine hepatocellular carcinoma.

Objectives Hyperadrenocorticism has been reported to cause left ventricular (LV) structural and functional abnormalities in human patients. The purpose of the present study was to assess the incidence and features of LV structural and functional changes in dogs with hyperadrenocorticism. Animals Twenty-two client-owned dogs with pituitary-dependent hyperadrenocorticism (n = 15) and cortisol-secreting adrenocortical tumors (n = 7) and 6 control dogs were enrolled in this study. Methods Echocardiographic examinations were performed and non-invasive measurements of systolic blood pressure (SBP) were obtained. Results The normalized LV wall thickness and LV mass index of the affected dogs differed significantly from those of control dogs. Using a published reference value for M-mode measurements, 15 of the 22 dogs (68%) were found to have increased LV wall thickness. Eleven of the 15 (73%) dogs with increased LV wall thickness were normotensive, and no significant correlation between LV wall thickness and SBP was found. Conclusions Regardless of the presence of systemic hypertension, hyperadrenocorticism should be included in the differential diagnosis of underlying disorders that may cause LV hypertrophy in dogs.

Dynamic left ventricular outflow tract obstruction (DLVOTO) is a common condition in cats and humans. In this case report, a dog is described with DLVOTO secondary to severe intra-abdominal hemorrhage caused by a hemangiosarcoma. The dog was a 9-year-old, 35.7-kg, spayed female German Shepard dog that presented with a history of tachypnea and collapse. A Levine II/VI systolic murmur was present at the heart base. Abdominal ultrasonography revealed a splenic mass and a large amount of ascites. Echocardiography showed a reduced left ventricular diameter and an increased aortic velocity caused by systolic anterior motion (SAM) of the mitral valve apparatus. The heart murmur and the SAM were resolved after treatment including a splenectomy and a blood transfusion.

Infective endocarditis (IE) in dogs with cardiac shunts has not been reported previously. However, we encountered a dog with concurrent patent ductus arteriosus (PDA) and IE. The dog was a 1-year-old, 13.9-kg female Border collie and presented with anorexia, weight loss, pyrexia (40.4 °C) and lameness. A continuous murmur with maximal intensity over the left heart base (Levine 5/6) was detected on auscultation. Echocardiography revealed a PDA and severe aortic stenosis (AS) caused by aortic-valve vegetative lesions. Corynebacterium spp. and Bacillus subtilis were isolated from blood cultures. The dog responded to aggressive antibiotic therapy, and the PDA was subsequently surgically corrected. After a series of treatments, the dog showed long-term improvement in clinical status.

Background Right-to-left (R-L) shunt caused by patent foramen ovale (PFO) concurrent with pulmonic stenosis (PS) is considered common, although there is a lack of published evidence. Objectives To investigate the prevalence of R-L shunt caused by a PFO in dogs with PS. Animals Thirty-one client-owned dogs with PS, without obvious extracardiac disease detected on the clinical examinations. Methods Case control study: R-L shunt probably caused by PFO was diagnosed when IV injected microbubbles appeared at the left atrial level with an intact atrial septum on echocardiography (bubble-positive dogs). The severity of PS concurrent tricuspid regurgitation (TR), relative thickness of the right ventricle, and relative right atrial area were compared between bubble-positive and bubble-negative dogs. Results The prevalence of R-L shunts caused by PFO was 39% (12 of 31 cases). The instantaneous pressure gradient (PG) across the pulmonic valve and relative thickness of the right ventricle were significantly increased in bubble-positive compared with those in bubble-negative dogs. None of the dogs with mild or moderate PS (pressure gradient

A two-month-old female Chihuahua was diagnosed as severe pulmonary valvular stenosis (PS). Although balloon valvuloplasty (BV) was successfully performed, restenosis was observed 19 months after the procedure. Euthanasia was chosen due to low output syndrome during the surgical repair attempted when the dog was 5 years old. Postmortem examination revealed markedly thickened pulmonary valve due to the increase of extracellular matrix which might be produced by increased α smooth muscle actin-positive myofibroblasts. The thickening of the valve was associated with restriction of the valve’s motion, resulting in restenosis in the present case. This is the first case report documented histopathological and immunohistochemical findings of the restenotic pulmonary valve in dogs with PS after BV.

Mitral valvuloplasty (MVP) is used in dogs with refractory mitral regurgitation (MR); however, it is difficult to tie the artificial chord, i.e., the expanded polytetrafluoroethylene suture, at the planned height of the mitral valve, because of the slippery nature of the knot. The loop technique has resolved these difficulties in humans. Premanufactured loops (length, 8.0-15.0 mm with 1.0-mm increments) were used in the new modified loop technique. In the current study, cardiac murmurs disappeared, and the MR markedly improved or completely disappeared approximately 3 months after surgery in 3 dogs. Therefore, this new technique might be effective in dogs.