A canine case of Ehrlichia canis infection without a history of being in an endemic area in Japan.

A mixed-breed, 8-year-old male dog developed neutropenia, thrombocytopenia, and hyperglobulinemia. Bone marrow hyperplasia and splenic plasmacytosis were cytologically observed. The dog had never been outside of Tokyo or Shizuoka Prefecture. Splenectomy was performed to confirm and remove the cause of splenic plasmacytosis. A histopathological diagnosis of splenic plasmacytoma was made; however, serum protein electrophoresis showed polyclonal gammopathy. Further screening was performed, and Ehrlichia canis infection was confirmed. The dog was treated with doxycycline for 5 weeks. After the antibiotic therapy, no relapse of neutropenia, thrombocytopenia, hyperglobulinemia, or positive polymerase chain reaction result of E. canis infection was observed for 3 years. Careful attention should be given to ehrlichiosis when exploring the cause of pancytopenia or hyperglobulinemia, regardless of the travel history.

Evaluation of the influence of the C-X-C motif chemokine ligand 12 / C-X-C chemokine receptor 4 axis on canine mammary gland tumor cell migration.

C-X-C motif chemokine ligand 12 (CXCL12) is one of the chemokines that binds to C-X-C chemokine receptor 4 (CXCR4) on tumor cell membranes and induces chemotaxis and/or migration. Mammary gland tumors (MGT) are the most common neoplasms in intact female dogs, with local invasion and distant metastasis regarded as problems. However, the influence of the CXCL12/CXCR4 axis on canine MGT cell migration has not been elucidated. This study aimed to evaluate the expression of CXCL12 and CXCR4 in canine MGT cells and tissues and investigate the influence of CXCL12 protein on the migratory ability of MGT cells. CXCL12 expression was evaluated in 10 canine malignant MGT tissues. CXCL12 expression in tumor cells was identified in all examined tissues; however, the staining pattern and intensity differed between the tumors. Immunocytochemistry revealed three canine MGT cell lines as CXCR4-positive. Migratory ability was evaluated using a wound healing assay, and the migration of CXCR4-positive MGT cells was significantly activated by the addition of CXCL12 protein. This influence was canceled by pre-treatment with a CXCR4 antagonist. The results of our study suggest that the CXCL12/CXCR4 axis may be associated with the migration of canine MGT.

Role of autopsy imaging in veterinary forensic medicine: experiences in 39 cases.

While numerous scientific studies have suggested the usefulness of autopsy imaging (Ai) in the field of human forensic medicine, the use of imaging modalities for the purpose of veterinary forensics is currently scant. The current study performed Ai on suspicious dead animals requested by the police department to determine their cause of death. Radiography and/or computed tomography and/or magnetic resonance imaging were performed on 39 suspicious dead animals before necropsy. After diagnostic imaging, pathological examination was performed, with drug testing added as needed. Among the 39 cases, 28, 6, 3, 1, and 1 involved cats, dogs, rabbits, a ferret, and a pigeon, respectively. The major Ai findings included skull and rib fractures, subcutaneous emphysema, pneumothorax, pneumoperitoneum, diaphragmatic hernia, and abdominal rupture. The leading causes of death, determined comprehensively via Ai and pathological reports and drug test results, included traumatic impact, blood loss, poisoning, suffocation, tension pneumothorax, starvation, and drowning, all of which have been strongly suspected to indicate animal abuse by humans. All eight cases of skull fractures and all five cases of poisoning, including suspected poisoning, were of cats. As the numbers of dogs and cats in Japan are almost equal, violence against cats may occur more frequently than dogs. Ai can be a valuable examination tool for veterinary forensic cases. As computed tomography is useful for ruling out fractures that screening computed tomography before necropsy is a more practical option for veterinary forensics.

Positive Intrapleural Pressure with Carbon Dioxide May Limit Intraoperative Pulmonary Arterial Bleeding: Verification by Animal Model.

PURPOSE: Intraoperative complications, especially unexpected bleeding, are of great concern in the safety of thoracoscopic surgery. We investigated the hemostatic efficacy and safety of positive intrapleural pressure (PIP) with carbon dioxide insufflation by assessing the amount of blood loss in a pulmonary arterial hemorrhage model. METHODS: An ex vivo experimental model of saline flow into a swine vessel was created in a container simulating a chest cavity. From the results, in vivo experiments (swine model) were conducted to compare the pulmonary arterial bleeding volume while applying PIP. RESULTS: In the ex vivo experiment, regardless of the incision type, the outflow volumes did not significantly differ at flow pressures of 20, 30, and 40 mmHg. At each flow pressure, the outflow volumes at 10, 15, and 20 mmHg of positive pressure in the container were significantly smaller than those of the control (p = 0.027, p = 0.002, and p = 0.005, respectively). Similarly, the in vivo experiments showed that bleeding decreased as intrapleural pressure increased (slope = -0.22, F = 55.13, p <0.0001). CONCLUSION: It may be possible to temporarily suppress pulmonary arterial bleeding by increasing the intrapleural pressure to 10 to 20 mmHg using carbon dioxide insufflation. This method may be an adjunctive hemostatic maneuver for intraoperative bleeding.

Assessment of Nasal Structure Using CT Imaging of Brachycephalic Dog Breeds.

The response to treatment of brachycephalic airway syndrome (BAS) varies among brachycephalic dog breeds. We hypothesized that variations in nasal structure are one of the factors responsible for this difference. To confirm this variation, we measured the ratio of the airway cross-sectional area to the total nasal cavity area (AA/NC) in three brachycephalic dog breeds. Head CT images of French bulldogs, shih tzus, and pugs were retrospectively collected. Four specific transverse planes were used to calculate AA/NC ratios. Fifty brachycephalic dogs were included in the study: French bulldogs (n = 20), shih tzus (n = 20), and pugs (n = 10). The AA/NC ratio of Shih Tzus was larger in the rostral nasal cavity and smaller toward the caudal area, whereas the other two breeds showed an inverse tendency. The results obtained from the current research indicate that the AA/NC ratio can be used to evaluate the structure of the nasal cavity. Moreover, analyzing the point with the smallest AA/NC ratio can be useful in quantifying nasal airway obstruction and the severity of BAS. These results will be useful in understanding the complexity of BAS pathophysiology and in the implementation of treatment.

Effects of combined one-lung ventilation and intrathoracic carbon dioxide insufflation on intrathoracic working space when performing thoracoscopy in dogs.

OBJECTIVE: To evaluate the effects of combining one-lung ventilation and carbon dioxide insufflation (OLV-CDI) on intrathoracic working space (determined by means of CT) during thoracoscopy in dogs and investigate conditions that could safely improve working space compared with OLV alone. ANIMALS: 6 healthy Beagles. PROCEDURES: Dogs were anesthetized, and right- or left-sided (n = 3/side) OLV was instituted. On the blocked side, a laparoscopic trocar sleeve was placed in the ninth intercostal space for CDI. CT was performed under 3 conditions: with OLV alone, with OLV-CDI at an intrapleural pressure (IPP) of 3 mm Hg, and with OLV-CDI at an IPP of 5 mm Hg. Working space volume (WSV), ventilation space volume (VSV), and thoracic cavity volume (TCV) were determined from CT images. RESULTS: With OLV-CDI at an IPP of 3 or 5 mm Hg, WSV and TCV were significantly increased, compared with values obtained during OLV alone. With OLV-CDI at an IPP of 5 mm Hg, VSV and Spo2 were significantly decreased, compared with values obtained during OLV alone. Additionally, contralateral pneumothorax was observed in 4 dogs at an IPP of 5 mm Hg. CLINICAL RELEVANCE: Combining OLV and CDI could provide a larger working space than OLV alone, even with an IPP of 3 mm Hg, in dogs of limited size. However, an evaluation of the effects on oxygenation and cardiovascular variables is needed before clinical use.

Screening of bacterial DNA in bile sampled from healthy dogs and dogs suffering from liver- or gallbladder-associated disease.

Although the biliary system is generally aseptic, gallbladder microbiota has been reported in humans and some animals apart from dogs. We screened and analyzed the bacterial deoxyribonucleic acid in canine gallbladders using bile sampled from 7 healthy dogs and 52 dogs with liver- or gallbladder-associated disease. PCR screening detected bacteria in 17.3% of diseased dogs (9/52) and none in healthy dogs. Microbiota analysis of PCR-positive samples showed that the microbial diversity differed between liver- and gallbladder-associated disease groups. Thus, a specific bacterial community appears to occur at a certain frequency in the bile of diseased dogs.

A preliminary animal study on the prediction of nerve block success using ultrasonographic parameters.

This study aimed to evaluate the diagnostic value of ultrasonographic parameters as an indicator for predicting regional nerve block success. Ultrasound-guided sciatic nerve block was performed in seven dogs using either 2% mepivacaine (nerve-block group) or saline (sham-block group). The cross-sectional area (CSA), nerve blood flow (NBF), and shear wave velocity (SWV) of the sciatic nerve (SWVN), SWV of the biceps femoris muscle (SWVM), and their ratio (SWVNMR) were measured at 0, 30, 60, and 90 min after the nerve block as well as the change rate of each parameter from the baseline. A receiver operating characteristic (ROC) curve analysis was performed to determine the diagnostic value of each parameter in the prediction of nerve block success. No significant changes were observed in the CSA or NBF in association with the nerve block. The SWVN and SWVNMR in the nerve-block group were significantly higher than those in the sham-block group at 90 min and at 30, 60, and 90 min, respectively (p < 0.05). The change rates of SWVN and SWVNMR in the nerve-block group were significantly higher than those in the sham-block group at all time points (p < 0.05). The ROC curve analysis showed that SWVN had a moderate diagnostic accuracy (area under the curve [AUC], 0.779), whereas SWVNMR and change rates of SWVN and SWVNMR had a high diagnostic accuracy (AUC, 0.947, 0.998, and 1.000, respectively). Ultrasonographic evaluation of the SWVN and SWVNMR could be used as indicators for predicting nerve block success.

Thoracic Wall Reconstruction with Dorsal Diaphragmatic Traction and Preservation of Diaphragmatic Attachments in a Dog with Resection of the 11-13th Ribs.

A 9-year-old, 4.7 kg, spayed female Chihuahua presented with a 3.5 cm soft tissue sarcoma on the dorsal right thoracic wall. The tumor was resected, including the 11−13th ribs, resulting in a caudal dorsal thoracic wall defect. The defect was reconstructed with direct traction of part of the diaphragm dorsally, preserving the diaphragmatic attachments to the body wall, and the diaphragm was sutured to the surrounding ribs and muscles. Possible respiratory complications, including paradoxical respiration and exercise intolerance, were not observed during the perioperative or postoperative observation periods. This novel procedure is expected to be an option for caudal thoracic wall reconstruction when the diaphragmatic attachments remain intact even after the resection of the last rib. In addition, this procedure can be performed in dogs weighing <5 kg, with small pleural cavities and without respiratory disorders.

Recurrence analysis of intraoperative acridine orange-photodynamic therapy for dogs with intranasal tumors.

Intraoperative acridine orange-photodynamic therapy (AO-PDT) and cribriform plate irradiation are used to treat canine intranasal tumors. The purpose of this study was to evaluate the effects of AO-PDT on intranasal tumors and the recurrence rate of tumors after this treatment. Treatments with AO-PDT were performed on 38 dogs through a narrow window of the dorsal nasal cavity. The median progression-free interval was 12 mo and recurrence was detected in 21 dogs. Based on computed tomography, recurrence in 16 dogs was biased to the following areas: lateral (n = 10), medial (n = 2), ventral (n = 0), rostral (n = 0), and caudal (n = 8). Side effects were mild and included subcutaneous emphysema and rhinitis. The median survival time was 24 mo. Although AO-PDT with cribriform irradiation is an effective treatment for intranasal tumors, AO-PDT techniques should be improved to treat the nasal cavity more uniformly and thoroughly.

Analyse de récurrence de la thérapie photodynamique peropératoire à l'acridine orange pour des chiens atteints de tumeurs intranasales. La thérapie photodynamique peropératoire à l'acridine orange (AO-PDT) et l'irradiation de la plaque cribriforme sont utilisées pour traiter les tumeurs intranasales canines. Le but de cette étude était d'évaluer les effets de l'AO-PDT sur les tumeurs intranasales et le taux de récidive des tumeurs après ce traitement. Des traitements avec AO-PDT ont été effectués sur 38 chiens à travers une fenêtre étroite de la cavité nasale dorsale. L'intervalle médian sans progression était de 12 mois et une récidive a été détectée chez 21 chiens. Sur la base de la tomodensitométrie, la récidive chez 16 chiens était biaisée dans les zones suivantes : latérale (n = 10), médiale (n = 2), ventrale (n = 0), rostrale (n = 0) et caudale (n = 8). Les effets secondaires étaient légers et comprenaient l'emphysème sous-cutané et la rhinite. La durée médiane de survie était de 24 mois. Bien que l'AO-PDT avec irradiation de la plaque cribriforme soit un traitement efficace pour les tumeurs intranasales, les techniques d'AO-PDT devraient être améliorées pour traiter la cavité nasale de manière plus uniforme et plus complète.(Traduit par Dr Serge Messier).

Surgical treatment of an abnormally positioned right adrenal tumor on segmental caudal vena cava aplasia in two dogs.

Segmental caudal vena cava (CVC) aplasia is a rare congenital vascular anomaly in dogs. Two dogs were diagnosed by CT imaging to have right adrenal tumors with concomitant segmental CVC aplasia. During surgery, a firm connection between the right adrenal gland and CVC was observed in both cases. The adrenal glands were found ventral to the CVC and the adrenal tumor was resected including the vascular wall. CVC venectomy for tumor removal will be required if the right adrenal gland is displaced in dogs with segmental CVC aplasia, even if there is no intravascular invasion.

Computed tomography of thoracic lymph nodes in 100 dogs with no abnormalities in the dominated area.

In dogs, reports on thoracic lymph nodes are lacking compared to abdominal lymph nodes. This report analyzed the position, number, size, shape, and homogeneity of thoracic lymph nodes (cranial sternal, cranial mediastinal, tracheobronchial, aortic thoracic, and pulmonary lymph nodes) using thoracic computed tomography (CT) images of 100 dogs without any lesions in the dominated areas of thoracic lymph nodes. The position and number of intrathoracic lymph nodes could be observed in CT, consistent with macroscopic anatomical studies. It was difficult to set a clinical index associated with size using CT scans. Image findings that indicated abnormalities, such as circular shapes and non-uniform, may be routinely found in dogs and may not be considered abnormal on CT scans.

Long-term effects of pleural defect repair using sheet materials in a canine model.

OBJECTIVE: A sheet material is widely used to repair pleural defects due to its excellent pressure resistance. We examined the long-term effects of sheet materials using an animal pleural defect model. METHODS: Beagles were used for this study. The 5-mm circular pleural defects were created at 2 sites on each of the anterior, medial, and posterior lobe and repaired using a 2 cm square sheet material. The frequency of adhesion of those sheets to the thoracic walls and histological changes was examined after 6 months. In this study, three types of sheet materials were examined: polyglycolic acid, nano-polyglycolic acid, and oxidized regenerated cellulose where each sheet was tested with or without coating with fibrin glue, for a total of 6 groups. Each group contained an equal number of defect sites and evaluation of 12 defect sites was conducted. RESULTS: Adhesion was observed in 16 of 72 sites (22%). Presence or absence of adhesion was not affected by the repair method or by the type of sheet material used. However, the use of fibrin glue significantly reduced the occurrence of adhesion (p = 0.023). At the defected sites, the posterior lobe showed significantly less adhesion (p = 0.019). Histologically, the sheet materials caused a thickening of the pleural wall 6-10 times thicker than the normal pleural wall. CONCLUSION: No statistically significant differences regarding the presence or absence of adhesion to the thoracic wall were found among the sheet materials. The use of fibrin glue significantly reduced the adhesion to the thoracic wall.

Video-assisted thoracic surgery anatomical lobectomy for a primary lung tumor in a dog.

A female Bernese Mountain Dog was diagnosed with a right middle lung lobe mass. The dog was positioned in a left lateral recumbency and one-lung ventilation was used under general anesthesia. Video-assisted thoracic surgery anatomical lobectomy was performed with 4 cm small thoracotomy and two 6-mm ports. Pulmonary vessels and bronchus were dissected and isolated individually at the hilum of the right middle lung lobe. Pulmonary vessels were ligated and were coagulated and transected using a vessel sealing device. The bronchus was ligated and transected. The mass in the right middle lung lobe was removed with a clean margin and without complications. Video-assisted thoracic surgery anatomical lobectomy was used to successfully remove a primary lung tumor in a dog.

Feasibility of complete surgical ligation on 72 dogs with singular extrahepatic congenital portosystemic shunt based on portal pressure and comparison of intraoperative mesenteric portovenography.

The relation between complete or partial ligation of extrahepatic portosystemic shunting and intraoperative mesenteric portovenography (IMP) was evaluated in 72 canines. Of the 72 dogs, 55 had complete ligation and 17 underwent partial ligation of abnormal vessels. IMP allowed evaluation of the number of intrahepatic portal branches and ratio of the diameter of cranial (CrPV) and caudal main portal vein (CaPV) at the shunt location. Nearly all cases in the complete ligation group and nearly half of the cases in the partial ligation group had three or more portal vein branches. CrPV/CaPV was 0.75 ± 0.24 in the complete ligation group and 0.29 ± 0.15 in the partial ligation group. CrPV/CaPV can be an effective new method for assessing IMP.

Sulfasalazine, an inhibitor of the cystine-glutamate antiporter, reduces DNA damage repair and enhances radiosensitivity in murine B16F10 melanoma.

The sodium-independent cystine-glutamate antiporter plays an important role in extracellular cystine uptake. It comprises the transmembrane protein, xCT and its chaperone, CD98. Because glutathione is only weakly cell membrane permeable, cellular uptake of its precursor, cystine, is known to be a key step in glutathione synthesis. Moreover, it has been reported that xCT expression affects the progression of tumors and their resistance to therapy. Sulfasalazine is an inhibitor of xCT that is known to increase cellular oxidative stress, giving it anti-tumor potential. Here, we describe a radio-sensitizing effect of sulfasalazine using a B16F10 melanoma model. Sulfasalazine decreased glutathione concentrations and resistance to H2O2 in B16F10 melanoma cells, but not in mouse embryonic fibroblasts. It synergistically enhanced the cyto-killing effect of X-irradiation in B16F10 cells. It inhibited cellular DNA damage repair and prolonged cell cycle arrest after X-irradiation. Furthermore, in an in vivo transplanted melanoma model, sulfasalazine decreased intratumoral glutathione content, leading to enhanced susceptibility to radiation therapy. These results suggest the possibility of using SAS to augment the treatment of radio-resistant cancers.

Efficacy of a sheet combined with fibrin glue in repair of pleural defect at the early phase after lung surgery in a canine model.

OBJECTIVE: Polyglycolic acid and oxidized regenerated cellulose have been widely used as a sealant for repairing pulmonary air leakage during respiratory surgery. However, fundamental research of these materials has not been sufficiently conducted. Therefore, we conducted studies to assess the pressure resistance ability of these materials using a canine visceral pleural defect model at the early phase. METHOD: The 6-mm circular defect and the 12-mm square defect were created on the visceral pleura of anesthetized beagles. These defects were then repaired using one of four methods: method A using polyglycolic acid and fibrin glue; method B using oxidized regenerated cellulose and fibrin glue; method C using oxidized regenerated cellulose; method D using fibrin glue. Airway pressure was measured as bursting pressure when air leakage from the repaired areas occurred at 5 min, 3 h, and 24 h after repair. RESULTS: For the 6-mm circle defect, method A showed higher bursting pressures than the other methods at 5 min and 3 h (p < 0.05); method B showed higher than methods C and D at 5 min and 3 h (p < 0.05). For the 12-mm square defect, method A showed higher bursting pressures than the other methods at all time points (p < 0.05). Moreover, method B showed higher than method C at 24 h (p < 0.05). CONCLUSION: Visceral pleural repairs using polyglycolic acid combined with fibrin glue showed the highest bursting pressure. Oxidized regenerated cellulose combined with fibrin glue showed sufficiently high bursting pressure in repair of small 6-mm circular defects.

Transrectal guidance of the ovaries reduces operative time during bovine laparoscopic ovariectomy.

The main objective of this study was to evaluate the effects of transrectal guidance of the ovaries by an assistant on operative time during bovine laparoscopic ovariectomy. Twenty four clinically healthy Holstein dairy cows were divided randomly into two groups. In the transrectal guidance group, an assistant grasped the ovaries via the transrectal route and pulled them to a position where they could be visualized with a camera. On the other hand, the control group was operated without guidance. The time required to remove both ovaries in the guidance group was shorter than that in the control group (P<0.01). We concluded that laparoscopic ovariectomy with transrectal guidance of the ovaries can substantially shorten operative time, thereby greatly contributing to animal welfare and to reducing the burden on the operator.

Pharmacological properties of various anesthetic protocols in 10-day-old neonatal rats.

In general, the anesthesia in neonates involves high risk. Although hypothermic anesthesia is recommended in rats up to the age of 7 days, neonatal anesthesia for later periods has not been standardized. The present study investigated the pharmacological properties of conventional anesthetic protocols in 10-day-old SD rats. The rats were anesthetized with four anesthetics: a combination of ketamine and xylazine (K/X); a combination of medetomidine, midazolam, and butorphanol (M/M/B); isoflurane; and sevoflurane. Anesthetic depth was scored by reflex response to noxious stimuli. Induction and recovery times were recorded. Vital signs and mortality rate were evaluated for safety assessment. All rats died after administration of K/X at a dose of 60/6 mg/kg, whereas K/X at 40/4 mg/kg resulted in insufficient anesthetic depth, indicating inappropriate for neonatal anesthesia. Although M/M/B at the adult rat dose (0.15/2/2.5 mg/kg) did not provide surgical anesthetic depth, the mouse dose (0.3/4/5 mg/kg) showed sufficient anesthetic depth with relatively stable vital signs. Isoflurane required a long induction period, and caused remarkable respiratory depression and hypothermia, resulted in a 25% mortality rate. In contrast, sevoflurane provided consistent surgical anesthetic depth with rapid induction. Although respiratory rate decrease was markedly observed, all rats survived. Among the anesthetic protocols investigated in the present study, sevoflurane and M/M/B at the mouse dose were recommended for the neonatal anesthesia. Compared with adult rats, the required dose of both anesthetics in neonates was higher, possibly associated with their lower anesthetic sensitivity.

A nasal osteoma with an acute course in a Japanese Black heifer.

A 14-month-old Japanese Black heifer presented with unilateral epistaxis and mild swelling of the right face. Radiography revealed a mass with increased radiopacity on the right side of the nasal bridge, extending to the left side. Intranasal endoscopy confirmed a large tumor-like structure protruding into the nasal cavity. Following euthanasia, cranial computed tomography (CT) was performed, revealing a tumor 24.3 × 17.5 × 14.8 cm in size. The tumor occupied the entire right nasal cavity and the frontal and sphenoid sinuses. Histopathological examination revealed that the tumor consisted of well-differentiated trabecular bones and loose connective tissue. Based on these findings, a diagnosis of osteoma was established. This report describes a case of osteoma with an acute course in a Japanese Black heifer.