Management of medial luxation of the shoulder joint in toy-breed dogs using an antiluxation pin placed lateral to the supraspinatus muscle tendon: 20 limbs (2017-2022).

OBJECTIVE: To describe the clinical and diagnostic findings, surgical procedures, and clinical course of dogs with medial shoulder luxation (MSL) treated with a novel method using an antiluxation pin. ANIMALS: 18 client-owned toy-breed dogs (20 treated limbs). CLINICAL PRESENTATION: Toy-breed dogs with MSL were treated with the antiluxation pin (2017 to 2022). The collected data included signalment, cause of luxation, preoperative and follow-up clinical evaluations with lameness scores (LMS), and radiographic and/or CT findings. RESULTS: Toy Poodle was the most represented breed (17 of 18 dogs [94.4%]). The median age was 10 years. One of 18 dogs had a history of trauma. Medial luxation was confirmed in all limbs using radiography or palpation under general anesthesia. Reluxation occurred in 3 limbs at 1, 4, and 30 days after surgery, respectively. Of these 3 limbs, 1 limb underwent revision to replace the original pin and the other 2 limbs underwent no further treatment. One limb with persistent pain underwent 2 revision surgeries to adjust the pin orientation 30 and 72 days after the initial surgery. Eighteen limbs remained unluxated after the initial or revision surgery until the final follow-up (median, 18.5 months; range, 1 to 63 months). The LMS at the final follow-up for the 18 unluxated limbs (mean, 0.5) was significantly lower than the preoperative LMS (mean, 4.5) (P < .01). CLINICAL RELEVANCE: A novel method of the antiluxation pin provides an alternative surgical treatment for MSL in toy-breed dogs that is minimally invasive and technically simple.

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.

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.

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.

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.

Use of skin stretchers for single-stage bilateral mastectomies in a dog and a cat.

OBJECTIVE: To describe the application of skin stretchers for closure of single-stage bilateral mastectomies in a dog and a cat. STUDY DESIGN: Clinical case report. ANIMALS: A 12-year-old intact female Miniature Dachshund and a 13-year-old spayed female domestic short-hair cat. METHODS: Skin stretchers were applied to the site of the skin adjacent to mammary glands for 2-4 days before surgery. Cable tension was adjusted every 6-8 hours to elongate the skin and to achieve primary closure of single-stage bilateral mastectomy without tension. RESULTS: Wound closure after single-stage bilateral mastectomy was achieved without tension or major complication in both animals. CONCLUSION: Use of skin stretchers allows primary closure of single-stage bilateral mastectomy in dogs and cats.

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.

Carcinome squameux causant une compression de la moelle épinière altantoaxiale dorsale chez un chien. Un Chihuahua âgé de 12 ans a été présenté pour de la douleur cervicale et une tétraparésie progressive. Une imagerie par résonance magnétique a révélé une compression de la moelle épinière en raison d'une masse dans la région atlantoaxiale dorsale. Le traitement chirurgical a été réalisé. La masse a été diagnostiquée à l'histopathologie comme étant un carcinome squameux. Le chien a retrouvé une condition neurologique normale après l'opération.(Traduit par Isabelle Vallières).

Determination of critical factors causing cytotoxicity in the virus neutralization test.

The fluorescent antibody virus neutralization (FAVN) test, an international standard method for serological testing for rabies, has been adopted by many countries. However, some dog serum samples inhibit the formation of cell monolayers by BHK-21 cells used in the test, resulting in failures to determine antibody titers. This inhibition of cell monolayer formation was defined as cytotoxicity. In this study, critical factors that induce cytotoxicity of the dog serum in BHK-21 cells were determined, and the effective ways to prevent cytotoxicity were also established. Specifically, some anticoagulants, anti-BHK-21 cell IgG antibodies, and serum storage at temperatures of >25°C were found to induce cytotoxicity. On the other hand, several treatments of the dog serum, including the absorption by BHK-21 cells or kaolin, incubation with trypsin-EDTA, and the use of collagen- or gelatin-coated plates, were shown to reduce cytotoxicity. Based on these results, the FAVN test may be modified to enhance its performance.

Neutralizing antibody response in dogs and cats inoculated with commercial inactivated rabies vaccines.

In Japan, the import quarantine regulation against rabies has required from 2005 that dogs and cats should be inoculated with the rabies vaccine and that the neutralizing antibody titer should be confirmed to be at least 0.5 international units (IU)/ml. The fluorescent antibody virus neutralization (FAVN) test is used as an international standard method for serological testing for rabies. To achieve proper immunization of dogs and cats at the time of import and export, changes in the neutralizing antibody titer after inoculation of the rabies vaccine should be understood in detail. However, few reports have provided this information. In this study, we aimed to determine evaluated, such changes by using sera from experimental dogs and cats inoculated with the rabies vaccine, and we tested samples using the routine FAVN test. In both dogs and cats, proper, regular vaccination enabled the necessary titer of neutralizing antibodies to be maintained in the long term. However, inappropriate timing of blood sampling after vaccination could result in insufficient detected levels of neutralizing antibodies.

A mimotope peptide of Aß42 fibril-specific antibodies with Aß42 fibrillation inhibitory activity induces anti-Aß42 conformer antibody response by a displayed form on an M13 phage in mice.

In Alzheimer's disease (AD), amyloid-ß (Aß) peptides accumulate in the brain in different forms, including fibrils and oligomers. Recently, we established three distinct conformation-dependent human single-chain Fv (scFv) antibodies, including B6 scFv, which bound to Aß42 fibril but not to soluble-form Aß, inhibiting Aß42 fibril formation. In this study, we determined the mimotopes of these antibodies and found a common mimotope sequence, B6-C15, using the Ph.D.-C7C phage library. The B6-C15 showed weak homology to the C-terminus of Aß42 containing GXXXG dimerization motifs. We synthesized the peptide of B6-C15 fused with biotinylated TAT at the N-terminus (TAT-B6-C15) and characterized its biochemical features on an Aß42-fibrillation reaction in vitro. We demonstrated that, first, TAT-B6-C15 inhibited Aß42 fibril formation; secondly, TAT-B6-C15 bound to prefibril Aß42 oligomers but not to monomers, trimers, tetramers, fibrils, or ultrasonicated fragments; thirdly, TAT-B6-C15 inhibited Aß42-induced cytotoxicity against human SH-SY5Y neuroblastoma cells; and, fourthly, when mice were administered B6-C15-phages dissolved in phosphate-buffered saline, the anti-Aß42 conformer IgG antibody response was induced. These results suggested that the B6-C15 peptide might provide unique opportunities to analyze the Aß42 fibrillation pathway and develop a vaccine vehicle for Alzheimer's disease.

Characterization of a bifunctional glyoxylate cycle enzyme, malate synthase/isocitrate lyase, of Euglena gracilis.

The glyoxylate cycle is a modified form of the tricarboxylic acid cycle, which enables organisms to synthesize carbohydrates from C2 compounds. In the protozoan Euglena gracilis, the key enzyme activities of the glyoxylate cycle, isocitrate lyase (ICL) and malate synthase (MS), are conferred by a single bifunctional protein named glyoxylate cycle enzyme (Euglena gracilis glyoxylate cycle enzyme [EgGCE]). We analyzed the enzymatic properties of recombinant EgGCE to determine the functions of its different domains. The 62-kDa N-terminal domain of EgGCE was sufficient to provide the MS activity as expected from an analysis of the deduced amino acid sequence. In contrast, expression of the 67-kDa C-terminal domain of EgGCE failed to yield ICL activity even though this domain was structurally similar to ICL family enzymes. Analyses of truncation mutants suggested that the N-terminal residues of EgGCE are critical for both the ICL and MS activities. The ICL activity of EgGCE increased in the presence of micro-molar concentrations of acetyl-coenzyme A (CoA). Acetyl-CoA also increased the activity in a mutant type EgGCE with a mutation at the acetyl-CoA binding site in the MS domain of EgGCE. This suggests that acetyl-CoA regulates the ICL reaction by binding to a site other than the catalytic center of the MS reaction.

Smoking induces bimodal DNA damage in mouse lung.

To clarify the relationship between DNA damage and free radical generation caused by smoking in vivo, DNA damage was investigated in the mouse lung by single-cell gel electrophoresis assay after exposure to cigarette smoke (CS) or gas phase cigarette smoke (GPCS). Although GPCS did not induce DNA lesions, bimodal peaks of DNA damage were detected in mouse lung exposed to CS, one immediately after exposure and another 15 min later. Pretreatment with a specific hydroxyl radical (•OH) scavenger completely prevented both types of DNA damage induced by CS. Electron spin resonance (ESR) study of the kinetics of free radical generation in CS or GPCS revealed that •OH could be detected immediately after the spin trapping of CS without chelators (first •OH generation), whereas •OH was also generated gradually with a time lag when the spin trapping was performed with chelators (second •OH generation). Our ESR study also indicated that the first •OH peak was probably generated from H(2)O(2) via a metal-independent pathway, whereas the second •OH peak might have been generated from H(2)O(2) and other sources via at least two different metal-masked pathways. The bimodal DNA damage induced in lung by smoking appears to be the result of a time lag between the first •OH generation and second •OH generation after exposure to the tar in CS.

Nationwide survey of salmonella prevalence in environmental dust from layer farms in Japan.

A nationwide survey was conducted to determine Salmonella prevalence in airborne dust from layer farms. Of the 4,090 layer farms in Japan, 203 were surveyed and 48 (23.6%) of these were positive for Salmonella. Salmonella isolation rates were higher in the eastern (24.3%), central (25.6%), western (23.9%), and southern (27.5%) prefectures than they were in the northern (13.3%) prefecture. We recovered 380 Salmonella isolates and identified 34 different Salmonella serovars. Salmonella Infantis was the most prevalent serovar (42 [11.1%] of 380), followed by Salmonella Agona (39 [10.3%] of 380), Salmonella Mbandaka (37 [9.7%] of 380), Salmonella Cerro (32 [8.4%] of 380), Salmonella Thompson (29 [7.6%] of 380), and Salmonella Braenderup (27 [7.1%] of 380). Of the 380 isolates, 273 (71.8%) were resistant to more than one antibiotic. Salmonella Infantis (41 [97.6%] of 42), Salmonella Agona (38 [97.4%] of 39), and Salmonella Mbandaka (34 [91.9%] of 37) showed the highest resistance rates. We found 18 different resistance patterns and the most common (179 [47.1%] of 273) was resistant to dihydrostreptomycin. One of the 13 Salmonella Hadar isolates was resistant to eight antibiotics. To investigate characteristics of Salmonella Agona, Salmonella Infantis, and Salmonella Mbandaka isolates across different prefectures, we performed pulsed-field gel electrophoresis by using XbaI and BlnI. The Salmonella Agona and Salmonella Mbandaka dendrograms were grouped into seven clusters, with 80 and 70% similarity, respectively. Because the Salmonella Infantis dendrogram showed low similarity, there is a possibility of genetic diffusion of this serovar across Japan. This report is the first to describe Salmonella contamination in airborne dust from layer farms in Japan. Our findings should be useful for future Salmonella infection monitoring and control.

Oral administration of the thyrotropin-releasing hormone (TRH) analogue, taltireline hydrate, in spinal muscular atrophy.

Spinal muscular atrophy is an entity of neurodegenerative disorders at the anterior horn neuron of the spinal cord caused by telomeric survival motor neuron gene abnormality. There is no definitive treatment for spinal muscular atrophy, but recent reports have indicated the efficacy of intravenous injection, but not oral administration, of thyrotropin-releasing hormone (TRH). We treated an 18-year-old male patient with spinal muscular atrophy type III by oral administration of the thyrotropin-releasing hormone analogue, taltireline hydrate. His muscle strength increased significantly after the therapy, and he showed no clinical or laboratory identifiable adverse effects, including thyroid-stimulating hormone suppression that had been observed with intravenous thyrotropin-releasing hormone therapy. Oral administration of this thyrotropin-releasing hormone analogue should be noted as a promising therapy for spinal muscular atrophy.

Expression of interleukin 8 in synovial tissues in patients with internal derangement of the temporomandibular joint and its relationship with clinical variables.

OBJECTIVES: The objectives of this study were to assay interleukin 8 (IL-8) in synovial tissues of the temporomandibular joint (TMJ) with symptomatic internal derangement, and to assess its relationship with clinical variables. STUDY DESIGN: Forty-six joints in 44 patients were examined using an immunohistochemical technique. As controls, 8 joints in 7 subjects with habitual dislocation without pain were also examined. RESULTS: IL-8 was expressed mainly in the blood vessels beneath the lining cells in 37 of the 46 joints (80%) with internal derangement and in 2 of the 8 control joints. The percentage of IL-8-positive cells was significantly higher in the internal derangement group than in the control group (P = .004). The percentage of IL-8-positive cells showed no correlation with joint pain or number of infiltrating cells. CONCLUSIONS: IL-8 was up-regulated in inflamed synovial tissues in patients with internal derangement. Because IL-8 has no significant correlation with clinical variables, IL-8 may play a secondary role in the pathogenesis of the internal derangement of the TMJ.

Seroepidemiologic survey of Coxiella burnetii and attempt to detect Coxiella DNA in aged non-laying chickens in a prefecture of Japan where poultry farming prospers.

The indirect fluorescent antibody test (IFAT) revealed seropositivity to Coxiella burnetii in aged non-laying chickens in poultry farms in a prefecture in the central part of Japan. Seropositivity was 7%, and antibody titers ranged from 16 to 64. No DNA fragment specific for C. burnetii was detected in the chickens by nested-PCR. The prevalence of C. burnetii infection in a prefecture of Japan in which poultry farming prospers was 7%.

Comparison of the clinical outcomes of patients having sounds in the temporomandibular joint with skeletal mandibular deformities treated by vertico-sagittal ramus osteotomy or vertical ramus osteotomy.

OBJECTIVE: This article describes the effects of the intraoral vertico-sagittal ramus osteotomy (IVSRO) procedure on the jaw of patients with temporomandibular joint (TMJ) disorders. STUDY DESIGN: IVSRO was performed on 15 patients (30 sides) who had mandibular protrusion or asymmetry with TMJ dysfunction. IVRO was performed on another 15 patients (30 sides). All of the 30 patients had sounds in the TMJ uni- or bilaterally. The relative positions of the condyle and disc and the range of motion of the condyles were determined by magnetic resonance imaging (MRI) before and 12 months after the operations. RESULTS: Sounds such as clicking improved in 92% (24/26) of the joints in the IVSRO group, and in 83% (20/24) of the joints in the IVRO group 12 months after the operation. The positional relationship between the condyle and disc on the MR images improved in 82% (9/11) of the joints with reduction of the anterior disc displacement; in 60% (3/5) of the joints without reduction of the anterior disc displacement in the IVSRO group; in 75% (9/12) of the joints with reduction of the anterior disc displacement; and in 40% (2/5) of the joints without reduction of the anterior disc displacement in the IVRO group. Immediately after the operation, the condyle was displaced anterio-inferiorly in all joints in both groups, but gradually returned to close to the preoperative position. There were no significant differences between the 2 groups regarding the extent of shift of the condylar head at 2 weeks and 12 months after the operation. CONCLUSION: The clinical outcomes of the IVSRO procedure are similar to those of the IVRO procedure. Therefore, IVSRO may be a suitable procedure for patients having TMJ dysfunction with skeletal mandibular deformities, particularly when an IVRO is unsuitable.