Cervical intervertebral disc disease in 307 small-breed dogs (2000-2021): Breed-characteristic features and disc-associated vertebral instability

OBJECTIVE

To evaluate the breed-characteristic features of cervical intervertebral disc disease (C-IVDD) and associated vertebral instability in small-breed dogs and to present the concept of intervertebral disc degeneration and associated instability stage, method of diagnosis, treatment and outcomes.

ANIMALS

In total, 307 client-owned dogs with C-IVDD treated with spinal cord decompression with or without vertebral stabilization (2000-2021).

METHODS

Information on age, sex, affected sites, stabilized sites, diagnostic methods for vertebral instability and outcomes were retrieved. The patient's age, affected sites (cranial vs caudal discs), and frequency of vertebral stabilization were compared in six CD and five NCD breed. Multivariable analyses of the chondrodystrophic (CD) vs non-CD (NCD) groups, and vertebral stabilization (dogs stabilized vs dogs not stabilized) were performed.

RESULTS

In total, 222 (72.3%) and 77 (25.1%) were CD and NCD breeds, respectively. Vertebral instabilities were diagnosed based on the survey radiographs with computed tomography/magnetic resonance imaging (n = 2), dynamic myelography (n = 29), intraoperative spinal manipulation (n = 11) or second surgery in dogs with persistent postoperative paraspinal pain (n = 3). Of these dogs, 295 (96.1%) recovered (median follow-up: 8.5 [range, 1-119] months). Significant differences in age, affected sites and frequency of stabilization were noted among the breeds. Older age and frequent vertebral stabilization were the associated factors for the NCD breed dogs. Male dogs, caudal discs affected (C5-T1) and the NCD breed dogs were risk factors for the dogs with vertebral stabilization.

CONCLUSION

Vertebral stabilization is indicated for small-breed dogs with cervical disc-associated vertebral instability.

Thoracic Vertebral Canal Stenosis and Vertebral Instability in a Young Minuet Cat

This report describes a unique case of thoracic vertebral canal stenosis and vertebral instability in a 1 yr old Minuet cat. The cat presented with a history of chronic progressive nonambulatory paraparesis. Myelography with neutral and stress positions revealed dynamic compression at T1-4. Computed tomography and MRI revealed multiple sites of vertebral endplate osteolysis, adjacent bone sclerosis, intervertebral disk space narrowing, and spondylotic bridging within the cervical and cranial thoracic vertebral bodies and pedicles, particularly at C6-T4. The cat underwent a right-sided T1-4 hemilaminectomy and C7-T4 vertebral stabilization using positively threaded profile pins and polymethylmethacrylate. The cat fully recovered without any complication. The case highlights the potential for young cats, especially those with a chondrodysplastic condition, to develop vertebral canal stenosis and vertebral instability. The surgical treatment described herein resulted in an excellent outcome.

Decompressive laminectomy with vertebral stabilization allows neurologic improvement of most Pekingese dogs with thoracolumbar vertebral instability

OBJECTIVE

To describe the diagnostic findings, surgical techniques, and outcomes of thoracolumbar vertebral instability associated with or without articular process (AP) anomalies in Pekingese dogs.

ANIMALS

11 client-owned Pekingese dogs.

PROCEDURES

Medical records (2007 to 2022) were reviewed. Inclusion criteria were Pekingese dogs with thoracolumbar vertebral instability that underwent decompressive laminectomy and vertebral stabilization. Dynamic myelographic study and/or intraoperative spinal manipulation were used to diagnose vertebral instability. Data on preoperative and postoperative neurologic status, diagnostic findings, surgical techniques, and outcomes were retrieved.

RESULTS

The dogs presented with paraparesis (n = 9) or paraplegia (2). Five dogs had caudal AP anomalies. Dynamic myelographic study demonstrated single (n = 7) or multiple (4) dynamic compressions with poststress spinal cord height reduction (median, 12.5%; IQR, 6.8% to 21.2%). Of the 17 dynamic compression lesions, 5 lesions were at the disc spaces with caudal AP abnormalities. All dogs had vertebral instability confirmed by intraoperative spinal manipulation and underwent hemilaminectomy and unilateral vertebral stabilization. One dog had adjacent segment vertebral instability and underwent vertebral stabilization 3 months after the initial operation. All but 1 dog showed successful outcomes at the last follow-up (median, 16 months; IQR, 3 to 32 months).

CLINICAL RELEVANCE

Vertebral instability associated with or without AP abnormalities is a potential cause of thoracolumbar spinal cord injury in Pekingese dogs. Dynamic myelographic studies and/or intraoperative spinal manipulation demonstrated vertebral instability. Spinal cord decompression and vertebral stabilization are effective, resulting in neurologic improvements in most dogs.

Pth1r Signal in Gli1+ Cells Maintains Postnatal Cranial Base Synchondrosis

Cranial base synchondroses are the endochondral ossification centers for cranial base growth and thus indispensable for proper skull, brain, and midfacial development. The synchondroses are composed of mirror-image growth plates that are continuously maintained from the embryonic to postnatal stage through chondrocyte differentiation. Several factors, including Pth1r signaling, are known to control fetal synchondrosis development. However, there are currently no reports regarding any role for Pth1r signaling in postnatal cranial base and synchondrosis development. Also, the mesenchymal cells that source Pth1r signaling for synchondroses are not known. Here, we employed an inducible mouse model, a hedgehog-responsive Gli1-CreERT2 driver, focusing on the postnatal study. We performed 2 inducible protocols using Gli1-CreERT2;Tomatofl/+ mice that uncovered distinct patterning of Gli1-positive and Gli1-negative chondrocytes in the synchondrosis cartilage. Moreover, we generated Gli1-CreERT2;Pth1rfl/fl;Tomatofl/+ mice to assess their functions in postnatal synchondrosis and found that the mutants had survived postnatally. The mutant skulls morphologically presented unambiguous phenotypes where we noticed the shortened cranial base and premature synchondrosis closure. Histologically, gradual disorganization in mutant synchondroses caused an uncommon remaining central zone between hypertrophic zones on both sides while the successive differentiation of round, flat, and hypertrophic chondrocytes was observed in control sections. These mutant synchondroses disappeared and were finally replaced by bone. Of note, the mutant fusing synchondroses lost their characteristic patterning of Gli1-positive and Gli1-negative chondrocytes, suggesting that loss of Pth1r signaling alters the distribution of hedgehog-responsive chondrocytes. Moreover, we performed laser microdissection and RNA sequencing to characterize the flat proliferative and round resting chondrocytes where we found flat chondrocytes have a characteristic feature of both chondrocyte proliferation and maturation. Taken together, these data demonstrate that Pth1r signaling in Gli1-positive cells is essential for postnatal development and maintenance in cranial base synchondroses. Our findings will elucidate previously unknown aspects of Pth1r functions in cranial biology and development.

Complete vaginectomy via a ventral approach with pelvic osteotomy in a cat

A 6-year-old, intact female, domestic short-hair cat had a 3-month history of obstipation. On physical examination and diagnostic imaging, megacolon secondary to a large, intrapelvic vaginal mass was diagnosed. An ovariohysterectomy and a complete vaginectomy via a ventral midline celiotomy and bilateral pubic and ischial osteotomies were performed. This approach allowed excellent exposure of the entire genital tract necessary to excise the large vaginal mass. The mass was histologically diagnosed as a vaginal fibrous stromal polyp. Obstipation resolved 12 h after surgery. On radiographic recheck 11 d after surgery, the colon had returned to normal size. No major surgical complications were observed. This is the first case report of a complete vaginectomy via the ventral approach with a pelvic osteotomy in a cat. Furthermore, this report describes the different surgical techniques used in animals affected by a large vaginal mass and provides evidence that an aggressive surgical approach and en-bloc excision can be considered for the management of extensive intrapelvic vaginal masses in cats.

Vertebral stabilisation for thoracolumbar vertebral instability associated with cranial and caudal articular process anomalies in pugs: Seven cases (2010-2019)

OBJECTIVES

To describe the diagnostic findings, surgical technique and outcomes in seven pugs with thoracolumbar vertebral instability due to articular process anomalies.

MATERIALS AND METHODS

Records (2010 to 2019) of pugs with thoracolumbar vertebral instability associated with articular process anomalies that underwent decompressive laminectomy and vertebral stabilisation were reviewed. Data on preoperative and postoperative neurologic status, diagnostic findings, surgical techniques and outcomes were retrieved.

RESULTS

Seven dogs were presented with ambulatory or non-ambulatory paraparesis. Caudal articular process anomalies (three dogs) and concomitant cranial and caudal articular process anomalies (four dogs) were noted. Myelography (six dogs) or magnetic resonance imaging (one dog) showed none to severe spinal cord compression. Dynamic myelography in six dogs demonstrated nine distinct sites of spinal cord dimension reduction positioned in extension and/or flexion (mean reduction: 16.0%, range: 8.5 to 24.0%). These dynamic compressions were located at sites with articular process anomalies (seven sites) and sites with no articular process anomalies (two sites). Vertebral instability was confirmed by intraoperative spinal manipulation in all dogs. All dogs remained ambulatory with improved (five dogs) or static (two dogs) neurological deficits at the last follow-up (median: 16 months; range: 1.5 to 66 months).

CLINICAL SIGNIFICANCE

Dynamic myelography and/or intraoperative spinal manipulation demonstrated vertebral instabilities at sites with or without articular process anomalies on imaging. Decompressive laminectomy with vertebral stabilisation resulted in long-term neurological improvement in most dogs.

Long-Term Outcome After Surgical Resection of a Spinal Choroid Plexus Tumor in a Dog

A 6 yr old castrated male Clumber spaniel was referred for evaluation of acute paraplegia. MRI of the thoracolumbar spine demonstrated an intradural-extramedullary mass lesion at the level of T12 and extradural spinal cord compression at L1-L2. A hemilaminectomy was performed to achieve gross total resection of the mass lesion and removal of extruded disc material. A diagnosis of spinal choroid plexus tumor (CPT) and intervertebral disc extrusion was made. At 4 mo postoperatively, MRI demonstrated a mass lesion at the right lateral aperture of the fourth ventricle. Spinal drop metastasis from a primary intracranial CPT was suspected. The dog was ambulating independently and neurologically normal at that time. At 17 mo postoperatively, a third MRI was performed owing to decreased postural reactions in both hind limbs and vision loss in the right eye, and it demonstrated an increase in size of the intracranial mass lesion. These two additional MRI studies of the entire central nervous system showed no other metastatic lesions nor any evidence of local recurrence. At 25 mo postoperatively, the dog died at home. This is the first case report of surgical intervention and antemortem histopathological diagnosis of a spinal CPT in a dog.

Levels of phospholipids and triacylglycerol-containing omega 3 fatty acids in myocardial tissue of patients with myocardial infarction: analyzed by a lipidomics profiling method

Objective

According to population-based studies, low omega 3 fatty acid (omega3FA) intake and high levels of serum triacylglycerol (TAG) are associated with cardiovascular diseases. Recent advances in mass spectrometry allow molecular lipid (lipidomics) profiling, which may enhance cardiovascular risk prediction. In this study, we assessed the levels of omega3FA-containing phospholipids (PL) and TAG in myocardial tissues of patients with and without myocardial infarction (MI) using a lipidomics profiling method.

Methods

We performed lipidomics profiling of human left atrial appendage (LAA) tissue of 29 consecutive patients receiving off-pump coronary bypass surgery with standard LAA resection. The patients were divided into the MI group (n=7) and an age- and gender-matched non-MI group (n=7).

Results

Lipidomics profiling revealed that the MI group tended to have low levels of phosphatidylcholines (PC), phosphatidylethanolamine (PE), lysophosphatidylethanolamine (LPE), and plasmalogen, and high levels of TAG species. Individual molecular species containing omega3FA, such as PC (18:0/20:5; 3,200±1,200 vs. 4,500±910 pmol/g tissue, p=0.04) and plasmalogen (18:1/20:5; 57,000±21,000 vs. 91,000±28,000 pmol/g tissue, p=0.02), were significantly lower in the MI group than in the non-MI group.

Conclusions

To our knowledge, this is the first study to determine the levels of omega3FA-containing PL and TAG in myocardial tissue using lipidomics profiling. We discovered that lower levels of omega3FA-containing PL and higher levels of TAG existed in myocardial tissues of patients with MI than in those of patients without MI. Accordingly, the lipidomics profiling method for human myocardial tissue may be useful for developing therapy targets for cardiovascular diseases.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): MEXT/JSPS KAKENHI Grant

P2634Prognostic value of admission left ventricular outflow tract velocity time integral in hospitalized heart failure patients with preserved ejection fraction: a report from the JASPER registry

Background

There are little effective treatment strategies for heart failure with preserved ejection fraction (HFpEF) to achieve a reduction of morbidity and mortality. Thus, accurate prognostication of patients with HFpEF could help improve their outcomes by identifying high-risk patients who might potentially benefit from intensive inpatient and outpatient monitoring and early referral for advanced HFpEF therapy. The left ventricular outflow tract velocity time integral (LVOT-VTI) is a representative non-invasive parameter for evaluating stroke volume, which can be a determinant of adverse outcomes in hospitalized patients with heart failure. However, the prognostic implication of admission LVOT-VTI for hospitalized HFpEF patients is undetermined.

Purpose

The aim of the present study was to investigate whether admission LVOT-VTI could predict poor clinical outcomes in hospitalized patients with HFpEF.

Methods

We examined consecutive 535 hospitalized HFpEF patients (left ventricular ejection fraction ≥50%) due to acute decompensated heart failure from the JASPER (JApanese heart failure Syndrome with Preserved Ejection fRaction) multicenter registry, obtained between November 2012 and March 2015. Patients without accessible LVOT-VTI data on admission were excluded. Finally, 214 patients were examined. The primary outcome of interest was composite of all-cause death and rehospitalization due to heart failure.

Results

Mean age was 78±11 years, 100 were male, and median plasma brain-type natriuretic peptide level was 400 (interquartile range [IQR] 223–711) pg/ml. During a median follow-up period of 688 (IQR 162–810) days, adverse events occurred in 83 patients (39%), including 47 (22%) all-cause death, 51 (24%) rehospitalization due to heart failure. The c-index of LVOT-VTI for predicting the composite of adverse events was 0.59 (95% CI 0.51 to 0.67), and the optimal cut-off value of LVOT-VTI was 15.8 cm. Low LVOT-VTI (≤15.8 cm) was significantly associated with higher adverse events compared to high LVOT-VTI (>15.8 cm) (Figure). Multivariable Cox regression analysis revealed that lower LVOT-VTI was an independent determinant of adverse events (HR 0.94, 95% CI 0.91 to 0.98, P=0.005) even after adjustment for pre-specified confounders including age, sex, systolic blood pressure, serum sodium, albumin, plasma brain-type natriuretic peptide and renal function.

Figure 1

Conclusions

Lower admission LVOT-VTI was an independent determinant of worse clinical outcomes in hospitalized HFpEF patients, indicating that LVOT-VTI on admission could be a useful marker for risk stratification in these patients.

4089Prognostic value of cardiac metabolic activity assessed by 18F-FDG PET in patients with cardiac sarcoidosis

Background

Sarcoidosis is a systemic granulomatous disease that affects multiple organs. Among these,the presenceof cardiac involvementis recognized as a determinant of worse clinical outcomes. 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a valuable modality for detecting active inflammatory lesions associated with cardiac sarcoidosis (CS). Generally,the maximum standardized uptake value (SUV) is suitable for evaluating disease activity in CS, but this quantitative method had limitations because it does not integrate both volume and intensity of FDG uptake simultaneously. Cardiac metabolic activity (CMA), which is quantitative measures of FDG volume-intensity, could be a diagnostic tool in the evaluation of CS. However, its prognostic implication in patients with CS is unclear.

Purpose

We sought to investigate whether CMA assessed by FDG-PET was associated with long-term worse clinical outcomes in patients with CS.

Methods

A total of 76 consecutive patients suspected CS who underwent FDG-PET between January 2010 and April 2018 in our university hospital were registered. We excluded patients whodid not meet the Japanese Ministry of Health and Welfare 2007 criteria (n=9) and those who received oral corticosteroids at the time of FDG-PET (n=5). Ultimately, 62 CS patients with definitively diagnosed were included in this study.We used a dedicated software to analyze SUV. Cardiac metabolic volume (CMV) was defined as the volume within the boundary determined by the threshold (SUV mean of blood pool × 1.5). CMA was calculated by multiplying CMV by SUV mean. The primary outcome of interest was the composite of advanced atrioventricular block, ventricular tachycardia, ventricular fibrillation, heart failure hospitalization, and all-cause death.

Results

During a median follow-up period of 1287 (IQR 806–1809) days after the first FDG-PET, the adverse events occurred in 12 patients (19%). Events group had significantly higher CMA compared to no events group (83 [IQR 11–330] vs. 354 [IQR 70–577]) (Figure A). Based on ROC analysis, the optimal cut-off value of CMA for the discrimination of the adverse events was 244 ml, and c-index was 0.71 (95% CI, 0.55–0.87). Patients with high CMA (≥244 ml, n=23) had lower LVEF, and higher prevalence of New York Heart Association functional class III or IV, and higher plasma BNP level compared to those with low CMA (<244 ml, n=39). Kaplan-Meier analysis revealed that composite adverse events more frequently occurred in patients with high CMA compared to those with low CMA (Figure B).Univariable Cox regression analysis showed that higher CMA was associated with increased subsequent risk of adverse events (HR 1.47, 95% CI 1.06–2.24).

Conclusions

Higher CMA assessed by FDG-PET was associated with worse clinical long-term outcomes in patients with CS, suggesting that measurement of the volume-intensity of abnormal FDG uptake may be useful for risk stratification in patients with CS.

P629Voluntary exercise associated with myokine production ameliorates cardiac remodeling and inflammation in a myocardial infarction mouse model

Background

Left ventricular (LV) remodeling, through excessive inflammation, leads to heart failure. Exercise (Ex) training is associated with a risk reduction in heart failure through direct and indirect mechanisms by which Ex contributes an anti-inflammatory effect. During Ex, contracting muscle fibers release myokines, including interleukins (ILs), tumor necrosis factor α (TNF-α), follistatin-like protein 1 (FSTL-1), and fibroblast growth factor 21 (FGF-21), into the bloodstream. These myokines may have beneficial effects on other damaged organs, such as an infarcted myocardium, through anti-inflammatory effects. However, the exact mechanisms of the anti-inflammatory effects of voluntary Ex in myocardial infarction (MI) are poorly understood. Therefore, we investigated the effect of voluntary Ex on cardiac remodeling and inflammation, the relationship between cardiac remodeling and skeletal muscle (SKM) response, and circulating myokine levels in a mouse model of MI.

Methods

Twelve-week-old male C57BL/6J mice were used and divided into the following 4 groups: sham operation (Sham), MI, Sham+Ex, and MI+Ex. MI was induced by ligation of the left anterior descending coronary artery. Ex groups began voluntary wheel running for 4 weeks after the operation. An echocardiography was performed at baseline and 4 weeks after the operation. The mRNA levels in the LV infarcted area and SKM were measured with RT-PCR and western blot analysis. Plasma levels of myokines were also measured with immunoassays.

Results

Four weeks after MI induction, echocardiographic evaluation showed that the MI mice had a larger LV end-diastolic diameter (LVEDD) and end-systolic diameter (LVESD) than the Sham mice. The MI mice also showed higher mRNA levels of TNF-α, IL-1β, IL-6, and IL-10 in the LV tissue when compared to the Sham mice. These changes were significantly ameliorated in the MI+Ex mice. Interestingly, in the MI+Ex mice, mRNA levels of IL-6, IL-1β, FSTL-1, and FGF-21 in the SKM were significantly higher than in the MI mice, while there were no significant differences in TNF-α and IL-10 levels in all groups. Similarly, protein expression levels of peroxisome proliferator-activated receptor gamma coactivator 1-alpha, sirtuin-1, and mitochondrial transcriptional factor A of mitochondrial function markers in SKM were also significantly higher in the MI+Ex mice than in the MI mice. Furthermore, there were significant correlations between plasma levels of IL-1β, but not other myokines, and LVEDD, and LVESD. In addition, there was also a significant correlation between the SKM IL-1β level and LVESD in the Sham+Ex mice (all, P<0.05).

Conclusions

Amelioration of cardiac remodeling and inflammation by voluntary Ex is associated with increased myokines, especially IL-1β, in a MI mouse model. These results suggest that increased myokine levels, through voluntary exercise, may play an important role in the prevention of cardiac remodeling after MI.

Clinical outcomes of 119 miniature- and toy-breed dogs with 140 distal radial and ulnar fractures repaired with free-form multiplanar type II external skeletal fixation

OBJECTIVE

To report the clinical outcomes of miniature- and toy-breed dogs with primary and previously treated distal radial and ulnar fractures (RUF) treated with a free-form multiplanar type II external skeletal fixation (ESF).

STUDY DESIGN

Retrospective study.

ANIMALS

One hundred nineteen dogs with 140 distal RUF.

METHODS

Medical records (2003-2017) were reviewed for dogs weighing up to 7 kg that had been treated for distal RUF with a free-form multiplanar type II ESF. Data collected included signalment, fracture location and configuration, fracture reduction, intraoperative realignment, time to bone union and implant removal, duration of destabilization and postoperative splint, complications, and outcomes. Follow-up consisted of clinical and radiographic evaluation or telephone interview.

RESULTS

All fractures healed, with a median time of 60 days, and entire ESF was removed, with a median time of 89 days. Major complications occurred in four fractures: premature pin loosening, elbow subluxation, osteomyelitis, and delayed union. Minor complications occurred in 52 fractures (61 events). All dogs had a successful return to normal limb function at final follow-up (median, seven months; range, 2-97).

CONCLUSION

All primary and previously treated distal RUF in miniature- and toy-breed dogs healed and allowed return to normal function after fixation with a free-form multiplanar type II ESF.

CLINICAL SIGNIFICANCE

The free-form multiplanar type II ESF provides an alternative for minimally invasive fixation of distal RUF in miniature- and toy-breed dogs that facilitates fracture reduction, intraoperative realignment, adequate initial fixation stability, destabilization, and implant removal.

Hemilaminectomy, Diverticular Marsupialization, and Vertebral Stabilization for Thoracolumbar Spinal Arachnoid Diverticula in Five Dogs

Medical records (2004-2016) of five dogs with a thoracolumbar spinal arachnoid diverticula (SAD) that was diagnosed with stress myelography in four dogs and magnetic resonance imaging in three, and who had hemilaminectomy, diverticular marsupialization, and vertebral stabilization, were reviewed. Data on previous treatment, pre- and postoperative neurologic status, diagnostic findings, surgical techniques, and outcomes was retrieved. Follow-up clinical and radiographic evaluations were performed immediately; ∼1, 2, and 6 mo postoperatively; and at annual follow-up examinations. The stress myelography demonstrated spinal cord dynamic compression in three of four dogs and change in size or shape of the SAD in all four. Two dogs who had SAD recurrences 4 and 13 mo after previous surgical dural fenestration, and one dog with no previous SAD treatment demonstrated long-term neurological improvement after vertebral stabilization (49, 77, and 126 mo). In two other dogs, recurrence of clinical signs was observed at the follow-up (8 and 12 mo). This case series suggested that repetitive spinal cord injury from the dynamic lesion appears to be one potential cause of thoracolumbar SADs. In cases with dynamic lesions confirmed by stress myelography, vertebral stabilization with conventional techniques is indicated to prevent SAD recurrence.

Clinical Outcomes and Complications after Open Reduction and Internal Fixation Utilizing Conventional Plates in 65 Distal Radial and Ulnar Fractures of Miniature- and Toy-Breed Dogs

Objective This article aims to evaluate clinical outcomes and complications of distal radial and ulnar fractures in miniature- and toy-breed dogs treated with conventional bone plate fixation.

Methods Medical records (2001–2010) of miniature- and toy-breed dogs with distal radial and ulnar fractures repaired with open reduction and internal fixation utilizing conventional plates were reviewed. The inclusion criteria were body weight of <7 kg, fracture located in the distal antebrachium (distal-to-total radial length ratio < 0.4) and follow-up radiographs available.

Results All 65 fractures healed without developing non-union, and had a successful return to normal function (median follow-up: 73 months; range: 2–149 months). Minor complication in seven fractures and major complication in four fractures were identified.

Clinical Significance Open reduction and conventional plate fixation of distal radial and ulnar fractures in miniature- and toy-breed dogs are effective means of fixation that result in normal functional outcome without developing non-union.

Primary colonic hemangiosarcoma in a dog

A 13-year-old spayed female miniature dachshund dog was presented with a history of hematochezia, melena, and weight loss. A colonic mass detected by exploratory celiotomy was resected and diagnosed as hemangiosarcoma (HSA). Liver lobectomy for hepatic HSA was performed 894 days after surgery. Adjuvant chemotherapy was declined. This is the first documentation of a canine colonic HSA.

Squamous cell carcinoma causing dorsal atlantoaxial spinal cord compression in a dog

A 12-year-old Chihuahua dog was presented for cervical pain and progressive tetraparesis. Magnetic resonance imaging revealed spinal cord compression due to a mass in the dorsal atlantoaxial region. Surgical treatment was performed. The mass was histopathologically diagnosed as a squamous cell carcinoma. The dog recovered to normal neurologic status after surgery.

Spontaneous Eosinophilic Granulated Round Cell Tumors in Rats

Morphologic and histochemical characteristics were noted for three spontaneous tumors with eosinophilic cytoplasmic granules that occurred in aged Fischer 344 rats. Macroscopic lesions were widely distributed in the body, mainly involving the intra-abdominal adipose tissue, pancreas, and mesenterium. These lesions were generally hard swellings with nodular and sclerosing areas. Bloody ascites was a concomitant finding. Histologically, the tumor cells were round, from 9 to 30 μm in diameter with one or two round to oval nuclei, and characterized by eosinophilic granules (0.5–2.0 μm) that stained definitely to weakly positive with the periodic acid-Schiff reaction and demonstrated no metachromasia with toluidine blue stain. Furthermore, the granules were characterized by a positive reaction with lectin histochemistry for concanavalin A (Con A), wheat germ agglutinin (WGA), phaseolus vulgaris agglutinin (PHA-E4), lens culinaris agglutinin (LCA), and recinus communis agglutinin (RCA-I) in all tumors and for ulex europaeus agglutinin (UEA-I), peanut agglutinin (PNA), and soybean agglutinin (SBA) in one tumor. Positive reactions for anti-rat mast cell protease II and CD8 were not demonstrated immunohistochemically. Abundant glycogen was noted in the large tumor cells from one rat. With electron microscopy, the cytoplasmic granules were identified as electron-dense homogenous bodies bounded by a single unit membrane. These characteristics are similar to those of granulated metrial gland cells, but further study is needed to clarify the cell of origin for these tumors.

A novel and rapid diagnostic method for discriminating between feces of sika deer and Japanese serow by loop-mediated isothermal amplification

Severe damages to natural vegetation, agriculture, and forestry caused by overpopulation of sika deer (Cervus nippon) have markedly increased in Japan in recent years. To devise a population management plan of sika deer, information on the distribution and population size of the animal in each region is indispensable. An easy and effective method to obtain this information is to count the fecal pellets in the field. However, the habitat of sika deer in Japan overlaps that of Japanese serow (Capricornis crispus). Additionally, it is difficult to discriminate between the feces of both animals. Here, we present a rapid and precise diagnostic method for discriminating between the feces of sika deer and Japanese serow using loop-mediated isothermal amplification (LAMP) targeting cytochrome b gene in the mitochondrial DNA. Our results showed that the LAMP can discriminate between the feces of sika deer and Japanese serow, and the method is simpler and more sensitive than the conventional molecular diagnostic method. Since LAMP method does not require special skills for molecular biology techniques, even the field researchers who have never done a molecular experiment can easily carry out the protocol. In addition, the entire protocol, from DNA extraction from fecal pellet to identification of species, takes only about 75 min and does not require expensive equipment. Hence, this diagnostic method is simple, fast, and accessible to anyone. As such, the method can be a useful tool to estimate distribution and population size of sika deer.

Enhancement of Runx2 expression is potentially linked to β-catenin accumulation in canine intervertebral disc degeneration

Intervertebral disc degeneration (IVDD) greatly affects the quality of life. The nucleus pulposus (NP) of chondrodystrophic dog breeds (CDBs) is similar to the human NP because the cells disappear with age and are replaced by fibrochondrocyte-like cells. Because IVDD develops as early as within the first year of life, we used canines as a model to investigate the in vitro mechanisms underlying IVDD. The mechanism underlying age-related IVDD, however, is poorly understood. Several research groups have suggested that Wnt/β-catenin signaling plays an important role in IVDD. However, the role of Wnt/β-catenin signals in IVD cells is not yet well understood. Here, we demonstrate that Wnt/β-catenin signaling could enhance Runx2 expression in IVDD and lead to IVD calcification. Nucleus pulposus (NP) tissue was obtained from Beagle dogs after evaluation of the degeneration based on magnetic resonance imaging (MRI). Histological analysis showed that lack of Safranin-O staining, calcified area, and matrix metalloproteinase (MMP) 13-positive cells increased with progression of the degeneration. Furthermore, the levels of β-catenin- and Runx2-positive cells also increased. Real-time reverse-transcription polymerase chain reaction analysis showed that the MRI signal intensity and mRNA expression levels of β-catenin and Runx2 are correlated in NP tissues. Moreover, supplementation of LiCl induced β-catenin accumulation and Runx2 expression. In contrast, FH535 inhibited LiCl-induced upregulation. These results suggest that Runx2 transcript and protein expression, potentially in combination with β-catenin accumulation, are enhanced in degenerated and calcified intervertebral discs of CDBs.

A drug formulation using an alginate hydrogel matrix for efficient oral delivery of the manganese porphyrin-based superoxide dismutase mimic

In order for patients to avail of the therapeutic benefits of antioxidant drugs efficiently and conveniently, a robust oral delivery system needs to be developed.

A comparison of thoracolumbar intervertebral disc extrusion in French Bulldogs and Dachshunds and association with congenital vertebral anomalies

OBJECTIVES

To compare data for French Bulldogs and Dachshunds that had hemilaminectomy for thoracolumbar intervertebral disc extrusion (T-L IVDE) by 1 surgeon and to evaluate the association between IVDE and congenital vertebral anomalies.

DESIGN

Retrospective case series.

ANIMALS

French Bulldogs (n = 47) and 671 Dachshunds.

METHODS

Age, gender, vertebral anomaly, kyphosis/kyphoscoliosis, IVDE site, non-recovery and progressive hemorrhagic myelomalacia development from grade 5 (paraplegia without deep nociception) were compared between the 2 breeds.

RESULTS

French Bulldogs were significantly younger (P = .00001), more likely to be male (P = .023), and more likely to have a congenital vertebral anomaly and kyphosis/kyphoscoliosis (P < .00001) than Dachshunds. The frequencies of French Bulldogs with IVDE within typical sites (T11-L3) were significantly lower (P = .0005) and within caudal sites (L3-L7) significantly higher (P = .0001) compared with Dachshunds. None of the French Bulldogs had IVDE within the kyphotic/kyphoscoliotic segment. The frequency of lumbar IVDE (L1-L5) in French Bulldogs with kyphosis/kyphoscoliosis was significantly higher (P = .003) compared with French Bulldogs without kyphosis/kyphoscoliosis. In grade 5 dogs, the risk of developing progressive hemorrhagic myelomalacia in French Bulldogs was significantly higher (P = .03) than in Dachshunds.

CONCLUSION

The distribution of IVDE site in French Bulldogs within the thoracolumbar and lumbar spine was different from Dachshunds. IVDE sites were not located at the sites of vertebral anomaly. French Bulldogs appeared to have T-L IVDE at younger ages, with higher male predisposition and higher risk of developing progressive hemorrhagic myelomalacia from grade 5 compared with Dachshunds.

Variations in gene and protein expression in canine chondrodystrophic nucleus pulposus cells following long-term three-dimensional culture

Intervertebral disc (IVD) degeneration greatly affects quality of life. The nucleus pulposus (NP) of chondrodystrophic dog breeds (CDBs) is similar to the human NP, because the cells disappear with age and are replaced by fibrochondrocyte-like cells. However, because IVD develops as early as within the first year of life, we used canines as a model to investigate in vitro the mechanisms underlying IVD degeneration. Specifically, we evaluated the potential of a three-dimensional (3D) culture of healthy NP as an in vitro model system to investigate the mechanisms of IVD degeneration. Agarose hydrogels were populated with healthy NP cells from beagles after performing magnetic resonance imaging, and mRNA expression profiles and pericellular extracellular matrix (ECM) protein distribution were determined. After 25 days of 3D culture, there was a tendency for redifferentiation into the native NP phenotype, and mRNA levels of Col2A1, COMP, and CK18 were not significantly different from those of freshly isolated cells. Our findings suggest that long-term 3D culture promoted chondrodystrophic NP redifferentiation through reconstruction of the pericellular microenvironment. Further, lipopolysaccharide (LPS) induced expression of TNF-α, MMP3, MMP13, VEGF, and PGES mRNA in the 3D cultures, creating a molecular milieu that mimics that of degenerated NP. These results suggest that this in vitro model represents a reliable and cost-effective tool for evaluating new therapies for disc degeneration.

Cleft Lip in Oculodentodigital Dysplasia Suggests Novel Roles for Connexin43

Oculodentodigital Dysplasia (ODDD) is a rare syndrome involving anomalies in eye, tooth, and digit formation, caused by mutations in CX43/ GJA1. In addition to classic dental features, ODDD includes oral and craniofacial accessory symptoms such as characteristic facial appearance and cleft palate. However, there have been no reports of ODDD accompanied by cleft lip. Herein we report, for the first time, a male, sporadic, Asian proband presenting bilateral cleft lip. By direct sequence analysis, our proband was diagnosed as having ODDD with a heterozygous mutation, codon 142 G>A in GJA1 and CX43E48K. We excluded the possibility of pathogenic mutations in B3GALTL, BMP4, TFAP2A, PVRL1, IRF6, and MSX1. To address how CX43/ GJA1 is related to cleft lip, we performed immunohistochemistry using mouse and human mid-facial tissue. CX43 expression was detected in the nasal compartment and nasal and maxillary processes at murine developmental stage E12.5. Furthermore, CX43 expression was found in the epithelial tissue inside the human subepithelial cleft lip that completes epithelial fusion. Therefore, we suggest that CX43/ GJA1 is involved in lip formation. Our case report of ODDD with a bilateral cleft lip suggests that CX43/ GJA1 might be a novel candidate gene for syndromic cleft lip.

Recurrent thoracolumbar intervertebral disc extrusion after hemilaminectomy and concomitant prophylactic fenestration in 662 chondrodystrophic dogs

OBJECTIVES

To determine the prevalence and location of recurrent thoracolumbar intervertebral disc extrusion (T-L IVDE) after hemilaminectomy with prophylactic fenestration (PF) and to document PF-related complications.

STUDY DESIGN

Retrospective case series.

SAMPLE POPULATION

Chondrodystrophic dogs (n = 793).

METHODS

In 662 successfully recovered dogs (>1 year follow-up), the prevalence of dogs with recurrent T-L IVDE that required a 2nd surgery and dogs with clinical signs that improved without surgery was evaluated. Prevalence of second disc extrusions (SDEs) within T11-L4 intervertebral discs was compared between PF discs and non-PF discs.

RESULTS

T-L SDEs were intraoperatively confirmed in 15 dogs (2.3%), 2-61 months after initial surgery and 66 dogs (10.0%) had signs of T-L IVDE recurrence that improved without surgery (mean follow-up, 44.7 months). No dog had further extrusion at the initial T-L site. SDE occurred at a PF disc (n = 1), adjacent to PF discs (8), or at distant discs (6). Prevalence of SDE in non-PF discs was 26.2 times higher than PF discs (95% CI: 3.4, 203.4; P < .001). Major PF-related complications included iatrogenic introduction of the disc material into the spinal canal (n = 1), and vertebral subluxation/instability (3) at 1-88 months postoperatively.

CONCLUSION

SDE is more likely to occur at non-PF discs than PF discs when PF is performed at spaces predisposed to disc extrusion. PF is a safe and effective treatment to prevent SDE in chondrodystrophic dogs.

Unilateral Hydronephrosis and Partial Ureteral Obstruction by Entrapment in a Granuloma in a Spayed Dog

A 6-year-old, spayed female dog had hydronephrosis and incomplete ureteral occlusion on the left side. An end-to-side ureteral anastomosis was performed. The incomplete ureteral occlusion was determined to be related to an ovarian pedicle granuloma formation and was presumably related to a reaction to the suture material used for ovariohysterectomy (OVH) performed 5 years prior to presentation. Azotemia and hydronephrosis were dramatically improved after surgery, and renal function has been well maintained for 3 years. To the authors’ knowledge, a chronic partial ureteral occlusion associated with an ovarian pedicle granuloma from an OVH has not been reported.

Large artery stiffening as a link between cerebral lacunar infarction and renal albuminuria

BACKGROUND

Stiffening of large arteries increases pulsatile pressure and flow stresses, which extend to the microcirculation in vasodilated organs such as the brain and kidneys. Subclinical cerebral lacunar infarction and albuminuria, both of which are early manifestations of microvascular damage, have been shown to be potentially interrelated in hypertension and with aging, but the underlying pathogenesis remains unknown.

METHODS

In a population of 351 general adults aged > or =50 years, urinary albumin/creatinine ratio (ACR), pulse wave velocity (PWV), and 24-h ambulatory blood pressure (BP) were measured, and cerebral lacunar lesions were assessed on magnetic resonance imaging (MRI).

RESULTS

Lacunar infarction was present in 86 subjects (25%). Subjects with lacunae had a higher median urinary ACR than those without (20.6 vs. 14.6 mg/g.Cr, P = 0.004). The positive association between the presence of lacunae and urinary ACR remained significant in a logistic model that adjusted for covariates including age, gender, and 24-h BP (P = 0.04); the odds ratio (OR) for lacunae was 1.32 for each 1 s.d. increase in urinary ACR. However, when PWV was added to this model, increased PWV but not urinary ACR was associated with lacunae. There was a significant interaction between urinary ACR and PWV with respect to lacunae; only subjects with a high PWV above the median showed an independent association between urinary ACR and the presence of lacunae (P = 0.03).

CONCLUSIONS

Microvascular damage in the brain (lacunar infarction) and kidney (albuminuria) appears to be interrelated in the general population. Large arterial stiffening may play a pivotal role in this cerebro-renal connection.

Nasolabial cyst in a patient with cleft lip and palate

Nasolabial cysts are rare non-odontogenic cysts that occur beneath the ala nasi, and debate about their complicated, unique pathogenesis continues. It is widely accepted that these lesions originate from the anlage of the nasolacrimal duct; however, some still think that nasolabial cysts arise from fissural cysts. The authors report a patient with a nasolabial cyst who also had a unilateral cleft lip and palate. This unusual finding may indicate a different origin for nasolabial cysts than what has been accepted in the past.

An uncommon cleft subtype of unilateral cleft lip and palate

The finding that the vomer plays a crucial role in maxillary growth suggests that the bilateral cleft configuration of unilateral cleft lip and palate (UCLP), in which the vomer is detached from the non-cleft-side secondary hard palate, negatively influences palatal development, and this hypothesis was tested. Sixty persons with complete UCLP, including those with the vomer detached from (n = 30, b-UCLP) and attached to (n = 30, u-UCLP) the secondary hard palate, were analyzed morphologically, with the use of cast models taken at 10 days, 3 mos, and 12 mos of age. The anterio-posterior palatal length at 12 mos of age in those with b-UCLP was significantly shorter than that in those with u-UCLP, by 8.7% (p < 0.05). In addition, palatal width development in the first year in those with b-UCLP was also significantly retarded. These results suggest that the uncommon bilateral cleft subtype in UCLP should be included in the cleft classification.

Association of microalbuminuria with brachial-ankle pulse wave velocity: the Ohasama study

BACKGROUND

Microalbuminuria is recognized as a marker of generalized vascular dysfunction. However, the associations between microalbuminuria and pulse wave velocity (PWV), carotid intima-media thickness (IMT), and ambulatory blood pressure (ABP), respectively, have not been investigated.

METHODS

Brachial-ankle PWV (baPWV), IMT, and ABP were determined in 328 individuals (mean age, 65.7 +/- 6.4 years) from the general population of Ohasama, a rural Japanese community. The participants were assigned to groups with microalbuminuria and with normoalbuminuria, and their characteristics were compared. We also examined the association between microalbuminuria and baPWV, IMT, and ABP, respectively, using multivariate analyses.

RESULTS

Seventy-nine participants (24%) with microalbuminuria had significantly higher baPWV (P < 0.001) and 24-h systolic BP (SBP) (P = 0.006) than those with normoalbuminuria, although 24-h pulse pressure and mean IMT did not significantly differ between the groups. Multiple logistic regression analyses showed that baPWV, but not 24-h ABP, was independently associated with microalbuminuria (P = 0.002) when adjusted for various confounding factors. After further adjustment for 24-h SBP, the association between baPWV and microalbuminuria remained significant (P = 0.012). The trend was significant even when daytime or nighttime SBP was used instead of 24-hour SBP in this model.

CONCLUSIONS

Microalbuminuria appears to be associated with baPWV more closely than with IMT and ABP, and its association with baPWV is independent of ABP and other cardiovascular risk factors.

Conditioning of karyoplasts for producing somatic nuclear transferred gonadal germ cells in domestic chickens

The objective of this study was to establish a protocol for generating karyoplasts that can be used to produce somatic nuclear transferred gonadal germ cells (snt-GGCs) in domestic chickens. Karyoplasts were produced by centrifuging cultured fibroblasts from 10-day-old chick embryos at 10,000 x g in the presence of 1.0 microg/ml cytochalasin B. The number of karyoplasts was significantly (P<0.05) higher and the diameters of the karyoplasts were significantly (P<0.05) smaller when fibroblasts were centrifuged for 60 min than for 10 or 30 min. It was possible to generate snt-GGCs by electrofusion of GGCs with karyoplasts produced from cryopreserved or serum-starved fibroblasts. These results indicate that karyoplasts generated from 10-day-old chick embryos can be used to produce snt-GGCs even after cryopreservation and serum starvation of the fibroblasts.

Tumor thickness and paralingual distance of coronal MR imaging predicts cervical node metastases in oral tongue carcinoma

BACKGROUND AND PURPOSE

The presence of cervical lymph node metastases is an important prognostic factor for oral tongue cancer. The accurate preoperative assessment is essential for treatment. Several studies have suggested that histologic tumor thickness is related to the metastases. The aim of this study was to determine whether MR images of oral tongue tumor have the potential to predict cervical lymph node metastases.

MATERIALS AND METHODS

A total of 43 patients with squamous cell carcinoma of the oral tongue were investigated. Tumor thickness, sublingual distance between tumor and sublingual space, and paralingual distance between tumor and paralingual space, as determined from coronal MR imaging, were preoperatively estimated. Logistic regression analysis was used to identify independent predictors of lymph node metastases.

RESULTS

Univariate logistic regression analysis showed that T classification, N classification, and 3 measured MR imaging distances (millimeters) were significantly associated with lymph node metastases. Multivariate logistic regression analysis showed that tumor thickness (odds ratio, 1.34; 95% confidence interval [CI], 1.11-1.63; P < .005) and paralingual distance (odds ratio, 0.53; 95% CI, 0.35-0.82; P < .005) were significant predictors for lymph node metastases. The probability of metastases was estimated with these models. The preoperative decision (20% probability) as to whether to perform neck dissection could be based on tumor thickness of >9.7 mm and paralingual distance of <5.2 mm.

CONCLUSION

MR images provide satisfactory accuracy for the preoperative estimation of the tumor thickness and the paralingual distance, which are valuable for predicting cervical lymph node metastases.

Vertebral Stabilization Using Positively Threaded Profile Pins and Polymethylmethacrylate, with or Without Laminectomy, for Spinal Canal Stenosis and Vertebral Instability Caused by Congenital Thoracic Vertebral Anomalies

OBJECTIVE

To describe diagnostic findings, surgical technique, and outcome in dogs with thoracic spinal canal stenosis and vertebral instability secondary to congenital vertebral anomalies.

STUDY DESIGN

Retrospective clinical study.

ANIMALS

Dogs (n=9) with thoracic spinal canal stenosis.

METHODS

Medical records (1995-1996; 2000-2006) of 9 dogs with a myelographic diagnosis of spinal canal stenosis and/or vertebral instability secondary to congenital vertebral anomaly that were surgically managed by vertebral stabilization with or without laminectomy were reviewed. Data on pre- and postoperative neurologic status, diagnostic findings, surgical techniques, and outcomes were retrieved. Follow-up evaluations were performed at 1, 2, and 6 months. Long-term outcome was assessed by means of clinical examination or owner telephone interviews.

RESULTS

Spinal cord compression was confirmed by myelography, and in 2 dogs, dynamic compression by stress myelography. Eight dogs regained the ability to ambulate postoperatively. One dog with a partial recovery regained voluntary movement but did not become ambulatory.

CONCLUSIONS

Spinal cord injury secondary to congenital vertebral anomaly may have a good outcome when treated by vertebral stabilization with or without laminectomy. Adequate stabilization of the vertebrae and improved neurologic outcome were achieved in most dogs.

CLINICAL RELEVANCE

Vertebral stabilization using positively threaded profile pins and polymethylmethacrylate with or without laminectomy is an effective treatment for spinal canal stenosis and vertebral instability secondary to congenital thoracic vertebral anomalies.

Spheric mass beneath the alar base: MR images of nasolabial cyst and schwannoma

We report 2 cases of nasolabial cyst and a case of schwannoma beneath the alar base that required a differential diagnosis because of clinical features and MR images that resembled the nasolabial cyst. The morphologic analysis on MR images revealed the characteristic appearance of the nasolabial cyst, and the sagittal MR image may be most helpful for diagnosing this rare disease.