REIRRADIATION OF RECURRENT CANINE NASAL TUMORS

Canine nasal tumors are typically treated with radiation therapy but most patients develop local recurrence. Our purpose was to evaluate tumor and normal tissue response to reirradiation in nine dogs. The median dose delivered with the first protocol was 50 Gy (range 44–55 Gy) and the median fraction number was 18 (range 15–20). For the second protocol, the median dose was lower intentionally, median of 36 Gy (range 23–44 Gy), without changing the median fraction number of 18 (range 14–20) to avoid late effects. The median time between protocols was 539 days (range 258–1652 days). Median survival was 927 days (95% confidence interval [CI] 423–1767 days). Median time to progression following the first and second courses was 513 days (95% CI 234–1180 days) and 282 days (95% CI 130–453 days), respectively. These were not significantly different (P=0.086). The qualitative response assessment was better for the first course compared with the second (P=0.018). Severity and timing of skin, mucous membrane, and ocular effects were similar for early side effects between the two courses (P>0.05 for all comparisons). All dogs experienced some late side effects, with two out of nine being classified as severe. These severe effects were blindness in each dog, possibly related to tumor recurrence. Reirradiation of canine nasal tumors resulted in a second clinical remission in eight of nine dogs, although the second response was less complete. Acute and late effects for seven of nine patients were not life threatening, indicating that reirradiation of canine nasal tumors may be a viable treatment option after recurrence.     

Expression of HER-2 and nuclear localization of HER-3 protein in canine mammary tumors: histopathological and immunohistochemical study

HER-2 and HER-3 are transmembrane receptor proteins that are considered to be important but poorly understood biomarkers in canine tumors. In this study, the expression and the localization of HER-2 and HER-3 were evaluated immunohistochemically in canine mammary tumors (n = 64; 12 benign, 52 malignant).HER-2 overexpression was identified in 2/12 (16.7%) benign and in 18/51 (35.3%) malignant cases. HER-3 was expressed in a non-nuclear localization in 11/12 (91.7%) benign and 18/52 (34.6%) malignant tumors. In contrast, HER-3 was expressed in the nucleus of neoplastic cells in 0/12 (0%) benign and 22/52 (42.3%) malignant tumors. Nuclear HER-3 expression was higher in neoplastic epithelial cells compared to myoepithelial cells, and positively correlated with high histological grade and lymphatic vessel invasion. These results suggest that nuclear HER-3 expression is significantly associated with tumor progression and metastasis and may serve as a useful prognostic biomarker in canine malignant mammary tumors.     

Occurrence and expression of p53 suppressor gene and c‐Myc oncogene in dog eyelid tumors

Purpose To detect the occurrence and expression of the suppressor gene p53 and of the oncogene c‐Myc in eyelid tumors of dogs using the PCR, RT‐PCR, PCR‐ELISA and RT‐PCR‐ELISA techniques. These genes have not been described in dog eyelid tumors before. Methods Nine samples of eyelid or third eyelid epithelial tumors were obtained from the archives of the Department of Veterinary Pathology. Tumor diagnosis was confirmed by evaluation of hematoxylin‐eosin stained sections, and immunohistochemistry for cytokeratin AE1/AE3 and vimentin V9. A canine mammary tumor was used for positive control. Agarose gel electrophoresis, PCR‐ELISA and RT‐PCR‐ELISA were used to detect p53 and c‐Myc genes. Results The occurrence of p53 was detected in most of the eyelid tumors and third eyelid tumors studied (88.8%, n = 8) and was expressed in 75% of the positive samples, as indicated by ELISA. The c‐Myc gene was found in 77.7% (n = 7) of the samples and was expressed in eight samples. Conclusions Eyelid and third eyelid tumors of dogs express both the p53 and the c‐Myc genes as shown by PCR and RT‐PCR. However, PCR ELISA and RT‐PCR ELISA were more efficient in assessing occurrence and expression of these genes because they identified amplified products that were not detected by agarose gel electrophoresis.     

动物冷应激的研究进展

综述了动物冷应激时神经系统的生理机制,及其对动物生产性能、免疫功能、抗氧化功能和血液中相关生理指标的影响,以及相关基因的研究进展。通过对动物冷应激时动物机体内的一系列变化规律的总结,为提高管理效率,减少动物冷应激带来的经济损失,以及冷应激相关科学研究的开展奠定了基础。     

A comparison of two dose calculation algorithms—anisotropic analytical algorithm and Acuros XB—for radiation therapy planning of canine intranasal tumors

Although anisotropic analytical algorithm (AAA) and Acuros XB (AXB) are both radiation dose calculation algorithms that take into account the heterogeneity within the radiation field, Acuros XB is inherently more accurate. The purpose of this retrospective method comparison study was to compare them and evaluate the dose discrepancy within the planning target volume (PTV). Radiation therapy (RT) plans of 11 dogs with intranasal tumors treated by radiation therapy at the University of Georgia were evaluated. All dogs were planned for intensity‐modulated radiation therapy using nine coplanar X‐ray beams that were equally spaced, then dose calculated with anisotropic analytical algorithm. The same plan with the same monitor units was then recalculated using Acuros XB for comparisons. Each dog's planning target volume was separated into air, bone, and tissue and evaluated. The mean dose to the planning target volume estimated by Acuros XB was 1.3% lower. It was 1.4% higher for air, 3.7% lower for bone, and 0.9% lower for tissue. The volume of planning target volume covered by the prescribed dose decreased by 21% when Acuros XB was used due to increased dose heterogeneity within the planning target volume. Anisotropic analytical algorithm relatively underestimates the dose heterogeneity and relatively overestimates the dose to the bone and tissue within the planning target volume for the radiation therapy planning of canine intranasal tumors. This can be clinically significant especially if the tumor cells are present within the bone, because it may result in relative underdosing of the tumor.     

急性冷应激对皖西白鹅某些神经内分泌活动的影响

以7日龄皖西白鹅为试验对象,研究在12±1℃室温条件下进行急性冷应激处理对下丘脑-垂体-肾上腺皮质(HPA)轴和下丘脑-垂体-甲状腺(HPT)轴的影响。结果表明,FT3在冷暴露6 h和12 h时显著升高。FT4冷暴露3 h显著升高(P<0.01),随后逐渐下降,至结束冷暴露后12 h显著降低(P<0.05)。T3在冷暴露过程中逐渐升高,在冷暴露6 h、结束冷暴露后0.5 h和3 h时明显高于应激前水平。T4在冷暴露6 h、结束冷暴露后6 h时达到峰值。Cor在冷暴露3 h时显著升高(P<0.05),并在冷暴露期间保持高水平。血清中ACTH随冷暴露时间延长而逐渐升高,在冷应激3 h时显著高于应激前的水平(P<0.01),至冷暴露结束后3 h时,ACTH再次明显升高(P<0.05)。     

ACANTHOMATOUS AMELOBLASTOMA OF THE MAXILLA OF AN ADULT ALPACA

An adult alpaca presented with a large maxillary swelling. Facial trauma or a tooth root abscess was suspected. Radiographically there was a large expansile lesion displacing the right maxillary teeth. An ameloblastoma was diagnosed histologically and palliative radiation therapy was attempted. Because of poor response to therapy and anorexia the animal was euthanized. Necropsy findings confirmed an ameloblastoma of acanthomatous type.     

Effect of spaying and timing of spaying on survival of dogs with mammary carcinoma

The risk of developing mammary gland tumors in dogs is significantly decreased by ovariohysterectomy at an early age. However, previous studies have not found a benefit to ovariohysterectomy concurrent with tumor removal in dogs with established mammary gland tumors, suggesting that the progression of these tumors is independent of continued estrogen stimulation. The purpose of this study was to evaluate the effect of spaying and of the timing of spaying on survival in dogs with mammary gland carcinoma. Signalment, spay status and spay age, tumor characteristics, treatment. survival, and cause of death of 137 dogs with mammary gland carcinoma were analyzed. The dogs were classified into 3 groups according to spay status and spay time: intact dogs, dogs spayed less than 2 years before tumor surgery (SPAY 1), and dogs spayed more than 2 years before their tumor surgery (SPAY 2). Dogs in the SPAY 1 group lived significantly longer than dogs in SPAY 2 and intact dogs (median survival of 755 days, versus 301 and 286 days, respectively, P = .02 and .03). After adjusting for differences between the spay groups with regard to age, histologic differentiation, and vascular invasion, SPAY 1 dogs survived 45% longer compared to dogs that were either intact or in the SPAY 2 group (RR = .55; 95% CI .32-.93; P = .03). This study reveals ovariohysterectomy to be an effective adjunct to tumor removal in dogs with mammary gland carcinoma and that the timing of ovariohysterectomy is important in influencing survival.