Computed tomographic characteristics of testicular teratoma in a cat.

A 5-year-old intact male mixed-breed cat weighing 4.5 kg was referred to our hospital with a left testicular mass. CT revealed mild heterogeneous contrast enhancement and calcification in the testicular mass. A well-defined, contrast-enhancing, multiloculated mass with fluid-filled areas was extended from the testicular mass in the scrotum to the caudal aspect of the left kidney. The abdominal mass extended to the right crus of the diaphragm, and the gastrointestinal tract was compressed dorsally. Histopathology was consistent with teratoma. Characteristic CT findings in a feline testicular teratoma may include calcification and cystic areas.

The effect of inspired oxygen concentration on oxidative stress biomarkers in dogs under inhalation anesthesia.

This study investigated oxidative stress biomarkers at 3 different oxygen concentrations in dogs under general anesthesia to determine whether high-concentration oxygen increases oxidative stress. Six healthy beagles were randomly assigned to receive 3 anesthesia protocols (inhalation of 40%, 60%, and 100% oxygen) during 3 hours of general anesthesia with sevoflurane, with at least one week in between each protocol. For each experiment, blood samples were collected at 0, 3, 6, and 24 hours after inhalation of oxygen. Derivatives of reactive oxygen metabolites, biochemical antioxidant potential, superoxide dismutase, and 8-hydroxydeoxyguanosine in the blood did not significantly differ among the 3 groups at any time point. This study is the first comparing high concentrations of oxygen with low concentrations of oxygen for anesthesia in dogs. According to our findings, 100% oxygen may not alter the oxidative stress level in dogs during general anesthesia with sevoflurane for 3 hours.

La présente étude a examiné les biomarqueurs oxydatifs de stress à trois concentrations différentes en oxygène chez des chiens sous anesthésie générale afin de déterminer si des concentrations élevées en oxygène augmentent le stress oxydatif. Six chiens beagles en santé ont été assignés de manière aléatoire pour recevoir trois protocoles d'anesthésie (inhalation de 40 %, 60 % et 100 % d'oxygène) pendant 3 heures d'anesthésie générale avec du sévoflurane, avec au moins une semaine entre chaque protocole. Pour chaque essai, des échantillons sanguins furent prélevés à 0, 3, 6 et 24 heures après l'inhalation d'oxygène. Des dérivés de métabolites oxygène réactif, le potentiel anti-oxydant biochimique, la superoxyde dismutase et le 8-hydroxydéoxyguanosine dans le sang n'ont pas différé significativement parmi les trois groupes à n'importe quel moment. Cette étude est la première à comparer des concentrations élevées en oxygène avec des concentrations faibles en oxygène lors d'anesthésie chez des chiens. Selon nos trouvailles, 100 % d'oxygène ne modifierait pas le niveau de stress oxydatif chez les chiens durant une anesthésie générale avec du sévoflurane pendant 3 heures.(Traduit par Docteur Serge Messier).

Mandibular Reconstruction by Using a Liquid Nitrogen-Treated Autograft in a Dog with an Oral Tumor.

A 10 yr old intact female German shepherd dog presented with a large peripheral odontogenic fibroma and malignant melanoma on her lower jaw. The tumor was resected with a unilateral subtotal rostral hemimandibulectomy. After the mandible was removed, it was devitalized intraoperatively by freezing it in liquid nitrogen. It was subsequently reimplanted. New bone tissue formed in the gap between the frozen bone and the host bone. The regenerated bone contained osteocytes, osteoblasts, and blood vessels. The cosmetic appearance of the dog was preserved. The dog had normal mastication. The malignant melanoma recurred rostral of the left canine tooth at 159 days after the reconstruction surgery. A subtotal hemimandibulectomy was consequently performed. This is the first reported case of mandibular reconstruction using a liquid nitrogen-treated autograft in a dog with oral tumors.

Kite Shield-Shaped Wedge Recession for Treatment of Medial Patellar Luxation in Seven Small-Breed Dogs.

OBJECTIVE: To document the trochlear depth (TD) and clinical outcome after kite shield-shaped wedge (K-wedge) recession trochleoplasty in toy-breed dogs with medial patellar luxation (MPL). STUDY DESIGN: Case series. ANIMALS: Seven toy-breed dogs (<5 kg) with uni- or bilateral grades II-IV MPL (10 stifles). METHODS: A K-wedge recession trochleoplasty was performed in all dogs in combination with other surgical procedures as treatment for MPL. The TD, the ratio of the proximal TD to patella thickness, and the presence of osteophytes were determined from computed tomography images taken pre-, and 1 and 12 months postoperative. Lameness scores and MPL grade were also recorded. RESULTS: The TD and the ratio of proximal TD to patella thickness increased significantly immediately postoperative and remained increased at 1 and 12 months postoperative. The osteophyte score was significantly higher at 12 months postoperative than preoperative. All dogs had a reduction in MPL grade and improvement in lameness postoperative. CONCLUSION: K-wedge recession trochleoplasty was successful in treating MPL in a series of toy-breed dogs and offers an alternate to other trochlear recession techniques.

Expression of NG2 proteoglycan in the degenerated intervertebral disc in dachshunds.

The pathogenesis of intervertebral disc (IVD) degeneration is not fully understood. The biomolecular signaling pathways involved in the IVD degeneration require further investigation. The aim of this study was to investigate the expression of NG2 proteoglycan in the degenerated IVD. IVD samples were obtained from 16 Dachshunds that were confirmed to have IVD herniation and subsequently underwent hemilaminectomy. The samples were subjected to histological and immunohistochemical (IHC) examinations. IHC revealed positive results for the expression of NG2 proteoglycan in all examined samples. The results showed the expression of NG2 proteoglycan by the degenerated IVDs.

Estimation of glomerular filtration rate in dogs by a single-blood sample method involving iodixanol.

OBJECTIVE: To establish a simplified single-blood-sample method (SBSM) involving iodixanol to estimate glomerular filtration rate (GFR) in dogs and compare data provided by that procedure with data provided by a conventional multiple-blood-sample method (MBSM) involving inulin. ANIMALS: 26 healthy dogs and 36 dogs with naturally occurring renal disease. PROCEDURES: Dogs were used in various preliminary experiments to establish protocols for the SBSM and the MBSM of GFR estimation. To evaluate the relationship between GFRs obtained by the SBSM and the MBSM each involving iodixanol, iodixanol (40 mg of I/kg) was administered IV to 26 healthy dogs and 36 dogs with renal disease; blood sample collection was performed before and at 60, 90, and 120 minutes after the injection. To evaluate the relationship between GFRs obtained by the SBSM involving iodixanol and the MBSM involving inulin, iodixanol (40 mg of I/kg) and inulin (50 mg/kg) were coadministered IV to 22 healthy dogs and 3 dogs with renal disease, followed by blood sample collection 30, 60, 90, and 120 minutes later. Serum iodixanol and inulin concentrations were separately determined by reverse-phase high-performance liquid chromatography. RESULTS: Findings revealed a correlation (r = 0.99) between GFR estimated by the SBSM and MBSM each involving iodixanol. Likewise, GFR estimated by the SBSM involving iodixanol was correlated (r = 0.89) with that estimated by the MBSM involving inulin. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that the SBSM involving iodixanol can be applied to estimate GFR in dogs, instead of use of an MBSM.

Performance of a new carbon dioxide absorbent, Yabashi lime® as compared to conventional carbon dioxide absorbent during sevoflurane anesthesia in dogs.

In the present study, we compare a new carbon dioxide (CO2) absorbent, Yabashi lime(®) with a conventional CO2 absorbent, Sodasorb(®) as a control CO2 absorbent for Compound A (CA) and Carbon monoxide (CO) productions. Four dogs were anesthetized with sevoflurane. Each dog was anesthetized with four preparations, Yabashi lime(®) with high or low-flow rate of oxygen and control CO2 absorbent with high or low-flow rate. CA and CO concentrations in the anesthetic circuit, canister temperature and carbooxyhemoglobin (COHb) concentration in the blood were measured. Yabashi lime(®) did not produce CA. Control CO2 absorbent generated CA, and its concentration was significantly higher in low-flow rate than a high-flow rate. CO was generated only in low-flow rate groups, but there was no significance between Yabashi lime(®) groups and control CO2 absorbent groups. However, the CO concentration in the circuit could not be detected (≤5ppm), and no change was found in COHb level. Canister temperature was significantly higher in low-flow rate groups than high-flow rate groups. Furthermore, in low-flow rate groups, the lower layer of canister temperature in control CO2 absorbent group was significantly higher than Yabashi lime(®) group. CA and CO productions are thought to be related to the composition of CO2 absorbent, flow rate and canister temperature. Though CO concentration is equal, it might be safer to use Yabashi lime(®) with sevoflurane anesthesia in dogs than conventional CO2 absorbent at the point of CA production.

Combination of serum phosphorylated neurofilament heavy subunit and hyperintensity of intramedullary T2W on magnetic resonance imaging provides better prognostic value of canine thoracolumbar intervertebral disc herniation.

The aim of this study was to evaluate the prognostic value of concurrent measurement of serum phosphorylated neurofilament heavy subunit (pNF-H) concentration and intramedullary T2W hyperintensity in paraplegic to paraplegic dogs. Our hypothesis was that concurrent measurement of these would provide a more accurate prediction of functional outcome in dogs with thoracolumbar intervertebral disc herniation (IVDH). A prospective case-control clinical study was designed using 94 dogs with acute onset of thoracolumbar IVDH. The association of serum pNF-H concentration, T2W hyperintensity on sagittal MRI (T2H/L2), deep pain perception and surgical outcome were evaluated with logistic regression analysis after three months for all 94 surgically treated dogs. Sensitivity to predict non-ambulatory outcome was compared among pNF-H and T2H/L2 and combination of both. Logistic regression analysis indicated that serum pNF-H concentration and T2H/L2 were significantly correlated with surgical outcome (P<0.05); however, deep pain perception was not (P=0.41). The results of logistic regression analysis indicated that the odds ratios of unsuccessful long-term outcome were 2.6 for serum pNF-H concentration, 1.9 for T2H/L2 and 2.3 for deep pain sensation. The sensitivity and specificity to predict non-ambulatory outcome for using serum parameter pNF-H>2.6 ng/ml, using T2H/L2 value of>0.84 and using both serum pNF-H and T2H/L2, were 95% and 75.7%, 65% and 86.5%, and 90.0% and 97.5%, respectively. Therefore, combined measurements of serum pNF-H and T2H/L2 might be useful for predicting long-term outcome in dogs with thoracolumbar IVDH.

Influence of phosphate-buffered sucrose solution on early graft function in feline renal autotransplantation.

Graft perfusion with cold heparinized saline has known to induce ischemia and reperfusion injury in feline kidney transplantation. In this study, the effects of phosphate-buffered sucrose solution and heparinized saline solution on early kidney graft function were compared in feline kidney autotransplantation. Perfusion of grafts with or without hypothermic storage with chilled phosphate-buffered sucrose solution prevented ischemia and reperfusion injury despite a very short ischemic time. The results of our study suggest that phosphate-buffered sucrose perfusion and storage solution should be effective to reduce ischemia and reperfusion injury despite a very short ischemic time in feline kidney transplantation.

Preliminary study of interaction of clarithromycin with tacrolimus in cats.

Tacrolimus (Tac) is a core immunosuppressive drug in human organ transplantation. In feline kidney transplantation, however, the cost of Tac therapy is a significant obstacle. Clarithromycin (CLM) increases the blood trough level of Tac, effectively reducing the Tac dosage in human transplant patients. The interaction between CLM and Tac in cats has not been reported. In this study, the effect of multiple CLM dosing on the pharmacokinetics of Tac in three healthy cats was investigated. The treatments included Tac at 0.3 mg/kg and Tac at 0.3 mg/kg + multiple-dose CLM at 10 mg/kg. Co-administration of CLM and Tac resulted in significant increases in the oral bioavailability of Tac. These preliminary findings suggest that administration of multiple doses of CLM may decrease the required Tac dosage in Tac-based immunosuppressive therapy used as an alternative to the classic cyclosporine-based protocol for feline renal transplantation.

High-molecular-weight polyethylene glycol enhances hypothermic storage of feline kidney cells.

Phosphate-buffered sucrose (PBSc) solution is effective for short-term hypothermic preservation of tissue during feline kidney transplantation. A high-molecular-weight polyethylene glycol (35,000 Da, PEG35) reportedly enhanced the protective effects against cold-induced tubular injuries in animal kidney transplantation models. We investigated the ability of PBSc solution containing PEG35 to preserve cultured feline kidney cells using in vitro WST-8 cell proliferation assays. PEG35 significantly improved cell viability during 24 hr of cold preservation. PBSc containing 20 g/l PEG35 achieved an effect almost equal to that of University of Wisconsin (UW) solution, the gold standard preservation solution used in human clinical kidney transplantation, for up to 24 hr of preservation. Our results suggest that PBSc containing PEG35 provides an excellent medium for graft cold storage during feline kidney transplantation.

Preliminary study of effects of multiple oral dosing of clarithromycin on the pharmacokinetics of cyclosporine in dogs.

Clarithromycin (CLM) has been known to increase the cyclosporine (CsA) trough level in human and feline organ transplant patients. However, the interaction of CLM with CsA has not been reported in dogs. In this study, the effects of multiple dosing of CLM on the pharmacokinetics of CsA in three healthy beagles were investigated. The treatments included CsA 10 mg/kg alone and CsA 10 mg/kg + multiple-dose of CLM 10 mg/kg. Co-administration of CLM with CsA resulted in significant increases of oral bioavailability of CsA. The results of our study suggest that administration of multiple therapeutic doses of CLM may decrease the required CsA dosage in CsA-based immunosuppressive therapy in renal transplanted dogs.

Presumptive acute lung injury following multiple surgeries in a cat.

A 12-year-old, 3.5-kg spayed female domestic shorthair cat had a tracheal mass identified as malignant B-cell lymphoma. The cat had tracheal resection and subsequently developed laryngeal paralysis. Due to multiple episodes of respiratory distress the cat subsequently had tracheal surgeries. Finally, the cat had a sudden onset of severe respiratory distress and collapsed. Computed tomography imaging and arterial blood gas analysis supported a diagnosis of acute lung injury.

Blessure pulmonaire aiguë présumée après plusieurs chirurgies chez un chat. Une chatte commune domestique stérilisée âgée de 12 ans qui pesait 3,5 kg avait une masse trachéale identifiée comme un lymphome B malin. La chatte a eu une résection trachéale et a ensuite développé une paralysie laryngienne. En raison de plusieurs épisodes de détresse respiratoire, la chatte a ensuite subi des chirurgies trachéales. Enfin, la chatte a souffert soudainement d'une détresse respiratoire et s'est effondrée. Une tomographie par ordinateur et une analyse des gaz du sang artériel a appuyé un diagnostic de blessure pulmonaire aiguë.(Traduit par Isabelle Vallières).

Evaluation of anticancer effects and enhanced doxorubicin cytotoxicity of xanthine derivatives using canine hemangiosarcoma cell lines.

Methylxanthine derivatives increase cAMP and are known to have diuretic, cardiac, and central nervous system stimulatory effects. Moreover, caffeine inhibits the development of tumors induced by various carcinogens. The aim of this work was to elucidate the anticancer effects on apoptosis of xanthine derivatives alone and with doxorubicin in canine hemangiosarcoma cells. Xanthine derivatives with or without doxorubicin were administered to cells, and the effects were investigated by measuring tumor cell proliferation, cell death (cytotoxicity) induction, and apoptosis by the expression of annexin V or caspase 3/7. Both caffeine and theophylline induced apoptosis, and the treated cells expressed annexin V and caspase 3/7. Both drugs enhanced doxorubicin-induced cytotoxicity; however, hypoxanthine showed no effect. These results indicate that theophylline is similar to caffeine; both drugs may enhance doxorubicin-induced cytotoxicity by inhibiting ATM/ATR kinases. Our data suggest that caffeine and theophylline have anticancer effects and can improve the treatment effect in canine hemangiosarcoma patients.

Application of the single blood sample method to estimate feline glomerular filtration rate in a clinically relevant situation.

To compare glomerular filtration rate (GFR) estimated by a single blood sample method, the non-ionic contrast medium iodixanol (40 mg I/kg) and the standard GFR tracer inulin (50 mg/kg) were co-administered as a bolus intravenous injection to 12 cats, followed by blood collection 60 and 90 mins later. Serum iodixanol and inulin concentrations were measured separately by high-performance liquid chromatography and colourimetric assay. A correlation (r = 0.90, P <0.01) was noted between GFR values estimated by the single-blood-sample method using iodixanol and inulin, indicating that this procedure can apply to feline GFR estimates, even if different GFR tracers are used. In a feline kidney transplantation study, the GFR was monitored subsequently by this simplified iodixanol method throughout a 750-day observation period with no adverse reactions. The results demonstrate that the simplified method, including the volume of distribution, can be used as an alternative or expedient tool in a clinically relevant situation.

Serum glial fibrillary acidic protein as a diagnostic biomarker in dogs with progressive myelomalacia.

In humans, increased levels of GFAP in the CSF and blood have been reported with various neural diseases. However, there has been no study describing the usefulness of GFAP in the blood for disease of the spinal cord in dogs. The aim of this study was to describe the utility of GFAP in serum for a diagnosis of progressive myelomalacia. Fifty-six dogs with acute thoracolumbar IVDD diagnosed by computed tomography with myelography or MRI were included. Serum specimens were collected at initial presentation from all cases and at follow-up examinations from some cases. Serum samples were assayed for GFAP concentrations using a commercially available GFAP ELISA Kit. Progressive myelomalacia was the final diagnosis in 8/51 cases (15.6%). Eight dogs had clinical signs suggestive of progressive myelomalacia, of which 6 were positive and 2 were negative by GFAP. Seven dogs had a detectable level of serum GFAP, of which 6 had the onset of progressive myelomalacia. The sensitivity and specificity of the GFAP to progressive myelomalacia were 75% and 97.7%, respectively. The results suggest the utility of GFAP in serum in the diagnosis of progressive myelomalacia.

Interaction of clarithromycin with cyclosporine in cats: pharmacokinetic study and case report.

Clarithromycin (CLM) has been known to increase the cyclosporine (CsA) trough levels in human transplant patients. However, the interaction of CLM with CsA has not been reported in cats. In this study, the effects of oral dosing of CLM on the pharmacokinetics and dosing of CsA in cats were investigated. Co-administration of CLM with CsA resulted in significant increases of oral bioavailability of CsA. In addition, CLM reduced the CsA dosage required to maintain the therapeutic CsA trough levels to almost 35% of the initial CsA therapy and the dose frequency was successfully replaced from a twice a day schedule to once a day in a feline kidney transplant patient. The addition of CLM to the regular CsA-based immunosuppression could be used as an effective alternative to classical ketoconazole treatment in feline kidney transplant patients and may result in substantial cost saving and convenience for the cat owners.

Aloe vera oral administration accelerates acute radiation-delayed wound healing by stimulating transforming growth factor-ß and fibroblast growth factor production.

BACKGROUND: Delayed wound healing is a significant clinical problem in patients who have had previous irradiation. This study investigated the effectiveness of Aloe vera (Av) on acute radiation-delayed wound healing. METHODS: The effect of Av was studied in radiation-exposed rats compared with radiation-only and control rats. Skin wounds were excised on the back of rats after 3 days of local radiation. Wound size was measured on days 0, 3, 6, 9, and 12 after wounding. Wound tissues were examined histologically and the expressions of transforming growth factor ß-1 (TGF-ß-1) and basic fibroblast growth factor (bFGF) were examined by immunohistochemistry and reverse-transcription polymerase chain reaction. RESULTS: Wound contraction was accelerated significantly by Av on days 6 and 12 after wounding. Furthermore, the inflammatory cell infiltration, fibroblast proliferation, collagen deposition, angiogenesis, and the expression levels of TGF-ß-1 and bFGF were significantly higher in the radiation plus Av group compared with the radiation-only group. CONCLUSIONS: These data showed the potential application of Av to improve the acute radiation-delayed wound healing by increasing TGF-ß-1 and bFGF production.

The effect of aloe vera oral administration on cutaneous wound healing in type 2 diabetic rats.

Delayed wound healing is one of the complications of diabetes mellitus. The present study was performed to investigate the effect of Aloe vera oral administration on open wounds in type 2 diabetic rats. Full thickness open wounds (1.5 × 1.5 cm) were created under general anesthesia on the backs of the rats. These rats were divided into two group, a control group (Group C) and an Aloe vera oral administration group (Group A). Each wound area was measured on days 1, 2, 4 and 8 postwounding. The stages of wound granulation tissues were evaluated histopathologically. The expression of transforming growth factor (TGF)-ß1 and vascular endothelial growth factor (VEGF) were determined by immunohistochemically. The wounds were significantly contracted in Group A on days 2, 4 and 8 postwounding. Histological results revealed that the inflammatory cell infiltration, angiogenesis, extracellular matrix deposition and epithelialization were promoted in Group A, respectively. The immunohistochemical results revealed that both TGF-ß1 and VEGF protein-positive cells increased in Group A on day 4 postwounding. We concluded that Aloe vera oral administration accelerated wound healing in type 2 diabetic rats.

Epidural spinal myelolipoma in a dog.

Epidural spinal myelolipoma was diagnosed in a 13-year-old, male Siberian husky that was referred for evaluation of progressive pelvic limb paresis and urinary incontinence. An epidural mass was detected by magnetic resonance imaging and computed tomography. The mass was removed and identified histopathologically as an epidural myelolipoma. Pelvic limb paresis improved after surgery, but urinary retention associated with neurological bladder dysfunction persisted.