In vitro evaluation of the antitumor activity of axitinib in canine mammary gland tumor cell lines

Background@#Axitinib, a potent and selective inhibitor of vascular endothelial growth factor (VEGF) receptor (VEGFR) tyrosine kinase 1,2 and 3, is used in chemotherapy because it inhibits tumor angiogenesis by blocking the VEGF/VEGFR pathway. In veterinary medicine, attempts have been made to apply tyrosine kinase inhibitors with anti-angiogenic effects to tumor patients, but there are no studies on axitinib in canine mammary gland tumors (MGTs). @*Objectives@#This study aimed to confirm the antitumor activity of axitinib in canine mammary gland cell lines. @*Methods@#We treated canine MGT cell lines (CIPp and CIPm) with axitinib and conducted CCK, wound healing, apoptosis, and cell cycle assays. Additionally, we evaluated the expression levels of angiogenesis-associated factors, including VEGFs, PDGF-A, FGF-2, and TGF-β1, using quantitative real-time polymerase chain reaction. Furthermore, we collected canine peripheral blood mononuclear cells (PBMCs), activated them with concanavalin A (ConA) and lipopolysaccharide (LPS), and then treated them with axitinib to investigate changes in viability. @*Results@#When axitinib was administered to CIPp and CIPm, cell viability significantly decreased at 24, 48, and 72 h (p < 0.001), and migration was markedly reduced (6 h, p < 0.05; 12 h, p < 0.005). The apoptosis rate significantly increased (p < 0.01), and the G2/M phase ratio showed a significant increase (p < 0.001). Additionally, there was no significant change in the viability of canine PBMCs treated with LPS and ConA. @*Conclusion@#In this study, we confirmed the antitumor activity of axitinib against canine MGT cell lines. Accordingly, we suggest that axitinib can be applied as a new treatment for patients with canine MGTs.

The application of electrochemotherapy in three dogs with inoperable cancers

Factors such as location, volume, and the type of neoplasm complicate achieving tumor control. Electrochemotherapy (ECT) is a supplementary treatment for inoperable neoplasms in veterinary patients. Three dogs were diagnosed with a tumor. Two were squamous cell carcinoma (SCC), and the other was liposarcoma, each with a single tumor with the size range of 1 to 5 cm. The tumor locations were the cervical, oral, and abdominal cavity. ECT was selected as a treatment. Bleomycin was injected intratumorally at the dose of 0.5 to 1.0 mg/cm3. Five minutes after the injection, electric pulses applied in a sequence of eight pulses lasting 100 µsec each, were delivered in 1,000 V/cm. An evaluation was performed after 1 week, and the next session was administered 2 weeks later. In a patient with oral SCC, the tumor was in partial remission after two sessions of ECT. Another patient with SCC on her neck was showed complete remission after 2 weeks of ECT administration. A third patient showed stable disease for 8 weeks. Complications were mild and transient and included skin necrosis, edema, local pain, and gait disturbance. ECT is a valid adjuvant, especially for inoperable, cutaneous, or accessible intra-abdominal tumors.

Retrospective evaluation of toceranib phosphate (Palladia) for treatment of different tumor types in 31 dogs

The purpose of this retrospective study was to provide additional data on the use of toceranib in a wide variety of tumor types in small breed dogs, especially < 8 kg (except 5 dogs). This was a retrospective study of 31 dogs with malignant tumors treated with a 2.5 mg/kg median dose of toceranib (Palladia; Zoetis, Florham Park, NJ, USA) on a Monday–Wednesday–Friday schedule. Clinical benefit was observed in 13 of 15 dogs (86.7%, 3 with complete response, 4 with partial response, 6 with stable disease) with gross disease. Distant metastasis, response to treatment, and treatment setting were significantly associated with survival time. Negative prognostic factors were multiple chemotherapy and distant metastasis (affecting progression-free survival [PFS]), surgery, regional enlarged lymph nodes, underlying disease, and toxicity (affecting median survival time [MST]). Positive prognostic factors were epithelial and round cell tumor (affecting PFS), epithelial tumor, microscopic disease, no evidence of disease response, and stable disease (MST). In conclusion, a clinical benefit from toceranib treatment was noted in most of the dogs with gross disease in our study. This study suggested that the toceranib is probably selective treatment to various tumor types in small breed dogs.

A retrospective study of 16 cats with intermediate- to high-grade alimentary lymphoma

The purpose of this retrospective study was to describe cases of feline intermediate- to high-grade alimentary lymphoma regarding signalment, clinical presentation, laboratory findings, response to therapy (modified 25-week University of Wisconsin–Madison [UW-25] vs. COP [cyclophosphamide, vincristine, prednisone]), toxicosis, and outcomes and to identify prognostic factors. Sixteen cats were treated with chemotherapy protocols. Response rates and survival did not differ statistically between the two protocols. The progression-free interval (PFI) and median survival time (MST) in cats achieving a response to therapy were longer than in those with no response [NR] (complete remission [CR] vs. partial remission [PR] vs. NR; PFI, 124 vs. 49 vs. 12 days, p < 0.001; MST, 361 vs. 118 vs. 16 days, p < 0.001). Clinical stage was another prognostic factor for PFI and MST. The PFI and MST in cats in stage I were longer than in those in other stages (PFI, 107 days vs. 30 days; MST, 193 days vs. 54 days). Hematologic and gastrointestinal toxicosis was mostly low grade. In comparing the modified UW-25 protocol with the COP protocol, there was not much difference in the number of neutropenic episodes and grade levels.

The application of electrochemotherapy in three dogs with inoperable cancers

Factors such as location, volume, and the type of neoplasm complicate achieving tumor control. Electrochemotherapy (ECT) is a supplementary treatment for inoperable neoplasms in veterinary patients. Three dogs were diagnosed with a tumor. Two were squamous cell carcinoma (SCC), and the other was liposarcoma, each with a single tumor with the size range of 1 to 5 cm. The tumor locations were the cervical, oral, and abdominal cavity. ECT was selected as a treatment. Bleomycin was injected intratumorally at the dose of 0.5 to 1.0 mg/cm3. Five minutes after the injection, electric pulses applied in a sequence of eight pulses lasting 100 µsec each, were delivered in 1,000 V/cm. An evaluation was performed after 1 week, and the next session was administered 2 weeks later. In a patient with oral SCC, the tumor was in partial remission after two sessions of ECT. Another patient with SCC on her neck was showed complete remission after 2 weeks of ECT administration. A third patient showed stable disease for 8 weeks. Complications were mild and transient and included skin necrosis, edema, local pain, and gait disturbance. ECT is a valid adjuvant, especially for inoperable, cutaneous, or accessible intra-abdominal tumors.

Retrospective evaluation of toceranib phosphate (Palladia) for treatment of different tumor types in 31 dogs

The purpose of this retrospective study was to provide additional data on the use of toceranib in a wide variety of tumor types in small breed dogs, especially < 8 kg (except 5 dogs). This was a retrospective study of 31 dogs with malignant tumors treated with a 2.5 mg/kg median dose of toceranib (Palladia; Zoetis, Florham Park, NJ, USA) on a Monday–Wednesday–Friday schedule. Clinical benefit was observed in 13 of 15 dogs (86.7%, 3 with complete response, 4 with partial response, 6 with stable disease) with gross disease. Distant metastasis, response to treatment, and treatment setting were significantly associated with survival time. Negative prognostic factors were multiple chemotherapy and distant metastasis (affecting progression-free survival [PFS]), surgery, regional enlarged lymph nodes, underlying disease, and toxicity (affecting median survival time [MST]). Positive prognostic factors were epithelial and round cell tumor (affecting PFS), epithelial tumor, microscopic disease, no evidence of disease response, and stable disease (MST). In conclusion, a clinical benefit from toceranib treatment was noted in most of the dogs with gross disease in our study. This study suggested that the toceranib is probably selective treatment to various tumor types in small breed dogs.

A retrospective study of 16 cats with intermediate- to high-grade alimentary lymphoma

The purpose of this retrospective study was to describe cases of feline intermediate- to high-grade alimentary lymphoma regarding signalment, clinical presentation, laboratory findings, response to therapy (modified 25-week University of Wisconsin–Madison [UW-25] vs. COP [cyclophosphamide, vincristine, prednisone]), toxicosis, and outcomes and to identify prognostic factors. Sixteen cats were treated with chemotherapy protocols. Response rates and survival did not differ statistically between the two protocols. The progression-free interval (PFI) and median survival time (MST) in cats achieving a response to therapy were longer than in those with no response [NR] (complete remission [CR] vs. partial remission [PR] vs. NR; PFI, 124 vs. 49 vs. 12 days, p < 0.001; MST, 361 vs. 118 vs. 16 days, p < 0.001). Clinical stage was another prognostic factor for PFI and MST. The PFI and MST in cats in stage I were longer than in those in other stages (PFI, 107 days vs. 30 days; MST, 193 days vs. 54 days). Hematologic and gastrointestinal toxicosis was mostly low grade. In comparing the modified UW-25 protocol with the COP protocol, there was not much difference in the number of neutropenic episodes and grade levels.

Correlation between NT-proBNP and lipase levels according to the severity of chronic mitral valve disease in dogs

Chronic mitral valve disease (CMVD) is the most common cardiovascular disease in dogs, causing decreased cardiac output that results in poor tissue perfusion and tissue damage to kidneys, pancreas, and other organs. The purpose of this study was to evaluate the relationships between heart disease severity and N-terminal pro B-type natriuretic peptide (NT-proBNP) and lipase in dogs with CMVD, as well as to evaluate longitudinal changes in these values. A total of 84 dogs participated in this 2015 to 2017 study. Serum values of NT-proBNP and lipase were analyzed; radiography was used to measure the vertebral heart score and assess various echocardiographic values. NT-proBNP showed a strong positive correlation with increasing stage of heart disease; lipase showed a mild positive correlation with heart disease stage. When the three values (NT-proBNP, lipase and month) were continuously measured at 6-month intervals, all showed a correlation with the increasing length of the disease.

Salivary alpha-amylase as a stress biomarker in diseased dogs

Salivary alpha-amylase (sAA) is a stress biomarker in human diseases, but there are no reports of sAA measurements in diseased dogs. This study measured the sAA and serum alpha-amylase (AA) levels in 16 healthy dogs and 31 diseased dogs using a kinetic enzyme assay to assess the stress status. The sAA and serum AA levels were significantly higher in the diseased dogs than in healthy dogs (p < 0.05), but there was no correlation between the 2 groups (r = 0.251, p = 0.089). This suggests that sAA can be useful as a stress biomarker in diseased dogs.

Clinical evaluation of a rapid diagnostic test kit for detection of canine coronavirus / 대한수의학회지

Canine coronavirus is a single-stranded RNA virus that causes enteritis in dogs of any age. Coronaviral enteritis is seldom definitively diagnosed, since it is usually much less severe than many other types of enteritis and is self-limiting. Conventional diagnostics for the canine coronaviral enteritis such as polymerase chain reaction (PCR), virus isolation, and electron microscopic examination are inappropriate for small animal clinics due to the complicated experimental processes involved. Therefore, a commercially available lateral flow test kit based on chromatographic immunoassay techniques was tested to evaluate its performance as a first-line diagnostic test kit that could be used in clinics. The coronavirus antigen test kit detected canine coronavirus-infected dogs with 93.1% sensitivity and 97.5% specificity. The detection limit of the test kit was between 1.97 × 10⁴/mL and 9.85 × 10³/mL for samples with a 2-fold serial dilution from 1.25 × 10⁶ TCID₅₀ (TCID₅₀, 50% tissue culture infectious dose). Additionally, the test kit had no cross-reactivity with canine parvovirus, distemper virus, or Escherichia coli. Overall, the commercially available test kit showed good diagnostic performance in a clinical setting, with results similar to those from PCR, confirming their potential for convenient and accurate use in small animal clinics.

Clinical management of suspected intracranial meningioma in three dogs with pulsed high-dose hydroxyurea / 대한수의학회지

Three aged dogs, all over 15 years old, with multiple seizure events and various neurologic signs such as head turn and ataxia were brought to the referring hospital. Two cases were tentatively diagnosed with intracranial meningioma based on magnetic resonance imaging, and one case was histopathologically confirmed as meningioma at necropsy. All dogs improved after initiation of pulsed high-dose hydroxyurea (HU) treatment. Clinical sign relapses were managed by repeating high-dose HU without obvious side effects. Pulsed high-dose HU can be applied when clinical signs are refractory to the traditionally recommended dosage for intracranial meningioma in dogs.

Clinical management of suspected intracranial meningioma in three dogs with pulsed high-dose hydroxyurea

Three aged dogs, all over 15 years old, with multiple seizure events and various neurologic signs such as head turn and ataxia were brought to the referring hospital. Two cases were tentatively diagnosed with intracranial meningioma based on magnetic resonance imaging, and one case was histopathologically confirmed as meningioma at necropsy. All dogs improved after initiation of pulsed high-dose hydroxyurea (HU) treatment. Clinical sign relapses were managed by repeating high-dose HU without obvious side effects. Pulsed high-dose HU can be applied when clinical signs are refractory to the traditionally recommended dosage for intracranial meningioma in dogs.

Clinical evaluation of a rapid diagnostic test kit for detection of canine coronavirus

Canine coronavirus is a single-stranded RNA virus that causes enteritis in dogs of any age. Coronaviral enteritis is seldom definitively diagnosed, since it is usually much less severe than many other types of enteritis and is self-limiting. Conventional diagnostics for the canine coronaviral enteritis such as polymerase chain reaction (PCR), virus isolation, and electron microscopic examination are inappropriate for small animal clinics due to the complicated experimental processes involved. Therefore, a commercially available lateral flow test kit based on chromatographic immunoassay techniques was tested to evaluate its performance as a first-line diagnostic test kit that could be used in clinics. The coronavirus antigen test kit detected canine coronavirus-infected dogs with 93.1% sensitivity and 97.5% specificity. The detection limit of the test kit was between 1.97 × 10⁴/mL and 9.85 × 10³/mL for samples with a 2-fold serial dilution from 1.25 × 10⁶ TCID₅₀ (TCID₅₀, 50% tissue culture infectious dose). Additionally, the test kit had no cross-reactivity with canine parvovirus, distemper virus, or Escherichia coli. Overall, the commercially available test kit showed good diagnostic performance in a clinical setting, with results similar to those from PCR, confirming their potential for convenient and accurate use in small animal clinics.

Serum nitrotyrosine concentration in dogs with myxomatous mitral valve disease

The aim of this study was to compare serum nitrotyrosine concentrations in healthy dogs with those in dogs with myxomatous mitral valve disease (MMVD). Fifty client-owned dogs were included in this study. Based on echocardiographic results, dogs were categorized into healthy (control), mild-, moderate-, and severe-MMVD groups. Serum nitrotyrosine concentrations were determined from enzyme-linked immunosorbent assays. No significant difference between control dogs and dogs with mild MMVD was detected (p = 0.31). However, dogs with moderate MMVD had significantly higher serum concentrations of nitrotyrosine (p = 0.04) than that in controls, and dogs with severe MMVD had significantly lower serum concentrations of nitrotyrosine (p = 0.03) than that in moderate MMVD dogs. There were negative correlations in the association of serum nitrotyrosine with age (n = 30, R²= 0.067, p = 0.27), left atrial-to-aortic root diameter ratio (n = 30, R²= 0.02, p = 0.57), and platelet count (n = 30, R²= 0.39, p = 0.003); however, only the platelet correlation was significant. Among dogs with MMVD, there was no significant difference in serum nitrotyrosine concentration between males and females. The results of this study suggest that tyrosine nitration end-products might be potential biomarkers for the detection of MMVD in dogs.

Identification and Characterization of Pseudocercospora pyricola Causing Leaf Spots on Aronia melanocarpa

Leaf spot disease on black chokeberry (Aronia melanocarpa) was observed at several locations in Korea during 2014–2015. Leaf spots were distinct, scattered over the leaf surface and along the leaf border, subcircular to irregular and brown surrounded by a distinct dark color, and were expanded and coalesced into irregularly shaped lesions. Severely infected leaves became dry and fell off eventually. The causative agent was identified as Pseudocercospora pyricola. Morphological observations and phylogenetic analyses of multiple genes, including internal transcribed spacer, translation elongation factor 1-alpha, actin, and the large subunit ribosomal DNA were conducted. The pathogenicity test was conducted twice yielding similar results, fulfilling Koch's postulates. To our knowledge, this is the first report on P. pyricola infection of A. melanocarpa globally.

Serum serotonin concentration in lean and obese dogs with myxomatous mitral valve disease

The aim of the present study is to investigate the potential influence of obesity as a factor in 5-hydroxytryptamine (5-HT) concentration in myxomatous mitral valve disease (MMVD) dogs. Fifty-five client-owned dogs were enrolled in a randomized trial. Dogs were classified by echocardiography into healthy (control), mild, and moderate to severe MMVD groups. Each group was subclassified by using a 9-point body condition score (BCS); lean (BCS 5–6/9) and obese groups (BCS 7.5–9/9). Dogs with moderate to severe MMVD had lower serotonin (5-HT) concentrations than the control group (p = 0.03). Dogs with moderate to severe MMVD (p = 0.017) had lower serum 5-HT concentrations than the control group in the obese group (BCS 7.5–9/9). Significant difference was found between the lean and obese groups (p = 0.015) which are not consider severe in the MMVD group. These results suggested that 5-HT concentration was decreased with the increasing severity of MMVD, and obesity might be taken into consideration when interpreting the serotonin concentration in MMVD dogs.

Molecular Detection of Giardia intestinalis from Stray Dogs in Animal Shelters of Gyeongsangbuk-do (Province) and Daejeon, Korea

Giardia is a major public health concern and considered as reemerging in industrialized countries. The present study investigated the prevalence of giardiosis in 202 sheltered dogs using PCR. The infection rate was 33.2% (67/202); Gyeongsangbuk-do and Daejeon showed 25.7% (39/152, P or =1 year of age which showed only 27.4% positive rate, 61.8% (P<0.001) of the total samples collected from young animals (<1 year of age) were positive for G. intestinalis. A significantly higher prevalence in symptomatic dogs (60.8%, P<0.0001) was observed than in asymptomatic dogs (23.8%). Furthermore, the analysis of nucleotide sequences of the samples revealed that G. intestinalis Assemblages A and C were found in the feces of dogs from Gyeongsangbuk-do and Daejeon. Since G. intestinalis Assemblage A has been known to infect humans, our results suggest that dogs can act as an important reservoir of giardiosis in Korea. Hence, hygienic management should be given to prevent possible transmission to humans.

Fecal microbiota analysis of obese dogs with underlying diseases: a pilot study / 대한수의학회지

Ten dogs were enrolled in this study: two healthy dogs, two obese dogs without other medical issues and six obese dogs with underlying diseases including pemphigus, chronic active hepatitis, hyperadrenocorticism, narcolepsy, otitis media and heartworm infection. Pyrosequencing of the 16S rRNA gene to explore the gut bacterial diversity revealed that distal gut bacterial communities of samples from patients with pemphigus, otitis media and narcolepsy consisted primarily of Firmicutes, while the major phylum of the distal gut bacterial communities in patients with chronic active hepatitis and hyperadrenocorticism was Fusobacteria. Proteobacteria were the dominant phylum in heartworm infected obese patients.

Application of vincristine-loaded platelet therapy in three dogs with refractory immune-mediated thrombocytopenia

Three dogs presented with refractory immune-mediated thrombocytopenia (IMT). All patients failed to respond to prednisone, which is considered a mainstay of immunosuppressive therapy. Vincristine-loaded platelets (VLPs), which act selectively on mononuclear phagocytes,were introduced. After the VLPs were transfused, two dogs responded quickly withimproved clinical signs while the third dogwith recurrent IMT was euthanized due to its deteriorating condition. This case report describesthe efficacy of VLP therapy in refractory IMT patients.

Prevalence of Dirofilaria immitis Infection in Stray Cats by Nested PCR in Korea

The purpose of this study was to conduct a survey of Dirofilaria immitis infection among stray cats in Korea using nested PCR. We included 235 stray cats (121 females and 114 males) and evaluated each for the presence of feline heartworm infection. Blood samples were collected from 135 cats in Daejeon, 50 cats in Seoul, and 50 cats from Gyeonggi-do (Province). Of the 235 DNA samples, 14 (6.0%) were positive for D. immitis. The prevalence of infection in male cats (8/114, 7.0%) tended to be higher than that in female cats (6/121, 5.0%), but the difference was not statistically significant. In each location, 8, 2, and 4 cats were positive for infection, respectively, based on DNA testing. No significant differences in the prevalence were observed among the geographic regions, although the rate of infection was higher in Gyeonggi-do (8.0%) than Daejeon (5.9%) and Seoul (4.0%). We submitted 7 of the 14 D. immitis DNA-positive samples for sequencing analysis. All samples corresponded to partial D. immitis cytochrome c oxidase subunit I gene sequences with 99% homology to the D. immitis sequence deposited in GenBank (accession no. FN391553). To the best of our knowledge, this is the first survey using nested PCR to analyze the prevalence of D. immitis in stray cats in Korea.