Osteochondrosis in the central and third tarsal bones of young horses.

Recently, the central and third tarsal bones of 23 equine fetuses and foals were examined using micro-computed tomography. Radiological changes, including incomplete ossification and focal ossification defects interpreted as osteochondrosis, were detected in 16 of 23 cases. The geometry of the osteochondrosis defects suggested they were the result of vascular failure, but this requires histological confirmation. The study aim was to examine central and third tarsal bones from the 16 cases and to describe the tissues present, cartilage canals, and lesions, including suspected osteochondrosis lesions. Cases included 9 males and 7 females from 0 to 150 days of age, comprising 11 Icelandic horses, 2 standardbred horses, 2 warmblood riding horses, and 1 coldblooded trotting horse. Until 4 days of age, all aspects of the bones were covered by growth cartilage, but from 105 days, the dorsal and plantar aspects were covered by fibrous tissue undergoing intramembranous ossification. Cartilage canal vessels gradually decreased but were present in most cases up to 122 days and were absent in the next available case at 150 days. Radiological osteochondrosis defects were confirmed in histological sections from 3 cases and consisted of necrotic vessels surrounded by ischemic chondronecrosis (articular osteochondrosis) and areas of retained, morphologically viable hypertrophic chondrocytes (physeal osteochondrosis). The central and third tarsal bones formed by both endochondral and intramembranous ossification. The blood supply to the growth cartilage of the central and third tarsal bones regressed between 122 and 150 days of age. Radiological osteochondrosis defects represented vascular failure, with chondrocyte necrosis and retention, or a combination of articular and physeal osteochondrosis.

Concentrations of canine prostate specific esterase, CPSE, at baseline are associated with the relative size of the prostate at three-year follow-up.

BACKGROUND: Enlargement of the prostate is associated with prostatic diseases in dogs, and an estimation of prostatic size is a central part in the diagnostic workup. Ultrasonography is often the method of choice, but biomarkers constitute an alternative. Canine prostate specific esterase (CPSE) shares many characteristics with human prostate specific antigen (PSA) and is related to prostate size. In men with clinical symptoms of prostatic disease, PSA concentrations are related to prostate growth. The aims of the present follow-up study were to evaluate if the concentration of CPSE is associated with future growth of the prostate, and if analysis of a panel of 16 steroids gives further information on prostatic growth. Owners of dogs included in a previous study were 3 years later contacted for a follow-up study that included an interview and a clinical examination. The prostate was examined by ultrasonography. Serum concentrations of CPSE were measured, as was a panel of steroids. RESULTS: Of the 79 dogs included at baseline, owners of 77 dogs (97%) were reached for an interview, and 22 were available for a follow-up examination. Six of the 79 dogs had clinical signs of prostatic disease at baseline, and eight of the remaining 73 dogs (11%) developed clinical signs between baseline and follow-up, information was lacking for two dogs. Development of clinical signs was significantly more common in dogs with a relative prostate size of ≥2.5 at baseline (n = 20) than in dogs with smaller prostates (n = 51). Serum concentrations of CPSE at baseline were not associated with the change in prostatic size between baseline and follow-up. Serum concentrations of CPSE at baseline and at follow-up were positively associated with the relative prostatic size (Srel) at follow-up. Concentrations of corticosterone (P = 0.024), and the class corticosteroids (P = 0.0035) were positively associated with the difference in Srel between baseline and follow-up. CONCLUSIONS: The results support the use of CPSE for estimating present and future prostatic size in dogs ≥4 years, and the clinical usefulness of prostatic size for predicting development of clinical signs of prostatic disease in the dog. The association between corticosteroids and prostate growth warrants further investigation.

Mutations in DNMT3B Modify Epigenetic Repression of the D4Z4 Repeat and the Penetrance of Facioscapulohumeral Dystrophy.

Facioscapulohumeral dystrophy (FSHD) is associated with somatic chromatin relaxation of the D4Z4 repeat array and derepression of the D4Z4-encoded DUX4 retrogene coding for a germline transcription factor. Somatic DUX4 derepression is caused either by a 1-10 unit repeat-array contraction (FSHD1) or by mutations in SMCHD1, which encodes a chromatin repressor that binds to D4Z4 (FSHD2). Here, we show that heterozygous mutations in DNA methyltransferase 3B (DNMT3B) are a likely cause of D4Z4 derepression associated with low levels of DUX4 expression from the D4Z4 repeat and increased penetrance of FSHD. Recessive mutations in DNMT3B were previously shown to cause immunodeficiency, centromeric instability, and facial anomalies (ICF) syndrome. This study suggests that transcription of DUX4 in somatic cells is modified by variations in its epigenetic state and provides a basis for understanding the reduced penetrance of FSHD within families.

Renal ultrasonographic abnormalities are associated with low glomerular filtration rate calculated by scintigraphy in dogs.

Ultrasound provides information on kidney morphology, but studies relating structural and functional abnormalities in chronic kidney disease (CKD) are lacking. The aim of this descriptive cross-sectional study was to compare individual kidney (IK) B-mode ultrasound abnormalities to IK glomerular filtration rate (GFR) estimated by scintigraphy normalized to plasma volume (PV) in dogs, to evaluate if ultrasonographic findings were associated with low IKGFR/PV. Eighty privately owned dogs with and without clinical suspicion of CKD were prospectively enrolled, and kidney ultrasound and IKGFR/PV were evaluated independently. Ultrasound images were assessed retrospectively for subjective abnormalities (shape, cortical, and medullary hyperechogenicity), and kidney size was measured. The normal IKGFR/PV cutoff was derived from dogs in the study group with no history and clinical signs of kidney disease and normal blood and urine results (n = 28) and was 16.84 mL/min/L. Kidneys were categorized into normal, mild, moderate, and severe ultrasound changes according to subjective ultrasound grades. Associations were found between low IKGFR/PV and abnormal kidney shape (P = .0004), cortical hyperechogenicity (P = .0008), medullary hyperechogenicity (P < .0001), and low kidney volume (P = .0092). Apart from the moderate and severe category comparison, IKGFR/PV value significantly decreased with increasing severity of category. The combination of ultrasonographic subjective abnormalities had a high sensitivity (93.8%) and moderate specificity (65.7%) for detecting low IKGFR/PV. Kidneys with normal IKGFR/PV had a low frequency of mild ultrasound changes. Findings indicate kidneys with increasing number and grade of subjective ultrasound abnormalities are more likely to have a lower IKGFR/PV.

Clinical and molecular characterization of an infant with a tandem duplication and deletion of 19p13.

Copy number variations (CNVs) on the short arm of chromosome 19 are relatively rare. We present a patient with a tandem de novo 3.9 Mb duplication of 19p13.12p13.2 and an adjacent 288 kb deletion of 19p13.12. The CNVs were detected by genome wide SNP-array and confirmed by fluorescence in situ hybridization. Mate-pair sequencing revealed two breakpoint junctions leading to a germline tandem inverted duplication and an adjacent deletion. The patient had a major congenital heart defect and refractory edema leading to metabolic and endocrinological disturbances. Further complications occurred due to refractory chylothorax, severe inflammatory response syndrome, and repeating sepsis. After 2 months, the child died due to intractable respiratory failure. The phenotype of this patient was compared with reported patients with overlapping deletions or duplications. We conclude that the congenital heart defect, respiratory insufficiency, and abnormal neurologic examination are most likely due the contiguous gene deletion/duplication.

Computed tomography is superior to radiography for detection of feline elbow osteoarthritis.

Elbow osteoarthritis (OA) is common in cats and radiography is typically used for diagnosis. However computed tomography (CT), with its multiplanar three-dimensional characteristics, could have significant advantages for assessment of OA compared to radiography, particularly early in the disease process. The study objectives were to compare radiography and CT to histologic OA changes, investigate the stage of OA that radiography and CT detect, and search for specific changes in CT images strongly predictive for feline elbow OA. Right elbows from 29 cats were evaluated by radiography and CT, and articular cartilage lesions graded histologically and macroscopically. Three further joints were sampled to specifically evaluate the morphology of the anconeal process. Macroscopic, radiographic and CT OA diagnosis were compared to the reference standard histologic OA that was divided into mild, moderate and severe. Osteophytic spurs on the lateral margin of the anconeal process could be reliably measured in CT images (intra-class correlation 0.79) and when ≥0.5 mm had high sensitivity for moderate/severe histologic OA, moderate sensitivity for mild histologic OA and high specificity for all stages of OA. In moderate/severe histologic OA both radiography and CT subjective OA diagnosis had moderate to very high sensitivity. However, in mild histologic OA CT grading had low sensitivity and radiography did not detect OA. In conclusion, CT of the feline elbow including measurement of osteophytes on the anconeal process lateral margin is superior to radiography for OA detection and should be considered for OA diagnosis, particularly when mild OA changes are of interest.

Quantification of sequence exchange events between PMS2 and PMS2CL provides a basis for improved mutation scanning of Lynch syndrome patients.

Heterozygous mutations in PMS2 are involved in Lynch syndrome, whereas biallelic mutations are found in Constitutional mismatch repair-deficiency syndrome patients. Mutation detection is complicated by the occurrence of sequence exchange events between the duplicated regions of PMS2 and PMS2CL. We investigated the frequency of such events with a nonspecific polymerase chain reaction (PCR) strategy, co-amplifying both PMS2 and PMS2CL sequences. This allowed us to score ratios between gene and pseudogene-specific nucleotides at 29 PSV sites from exon 11 to the end of the gene. We found sequence transfer at all investigated PSVs from intron 12 to the 3' end of the gene in 4 to 52% of DNA samples. Overall, sequence exchange between PMS2 and PMS2CL was observed in 69% (83/120) of individuals. We demonstrate that mutation scanning with PMS2-specific PCR primers and MLPA probes, designed on PSVs, in the 3' duplicated region is unreliable, and present an RNA-based mutation detection strategy to improve reliability. Using this strategy, we found 19 different putative pathogenic PMS2 mutations. Four of these (21%) are lying in the region with frequent sequence transfer and are missed or called incorrectly as homozygous with several PSV-based mutation detection methods.

A complex chromosome 7q rearrangement identified in a patient with mental retardation, anxiety disorder, and autistic features.

We have characterized a de novo complex rearrangement of the long arm of chromosome 7 in a female patient with moderate mental retardation (MR), anxiety disorder, and autistic features. G-banding suggested a de novo paracentric inversion 46,XX,inv(7)(q31.3q34). However, SNP-array analysis, showed a +/-10 Mb, 7q21.11-q21.3 deletion in the paternal chromosome. Subsequent FISH analysis with BAC/PAC clones in the 7q21-q35 region confirmed this deletion. However, the expected paracentric inversion turned out to be an intra-chromosomal insertion of the 7q31.31-q35 fragment into band 7q21.3, disrupting the predicted gene C7orf58 in band 7q31.31. Seven other patients have been previously reported with a deletion of 7q21.1-q21.3. Although there is an overlap in phenotype between our patient and these patients, none of them has been described with anxiety disorder and/or autistic features. Therefore we suggest that disruption of the C7orf58 gene might contribute to the anxiety disorder, and autistic features in our patient.

Computed tomography characteristics of equine paranasal sinus cysts.

BACKGROUND: Computed tomography (CT) is commonly used to investigate equine paranasal sinus disease, however, only limited information is available in the literature about the detailed CT appearance of equine paranasal sinus cysts. OBJECTIVES: To investigate if paranasal sinus cysts have specific characteristics in CT images that allow differentiation from other sinus diseases. STUDY DESIGN: Retrospective observational study. METHODS: Evaluation and comparison of CT studies of eight horses with surgically and/or histopathologically confirmed paranasal sinus cysts and 10 horses with other confirmed paranasal sinus diseases. RESULTS: A discrete hyperattenuating wall-like structure was detected in the periphery of the sinus lesion in precontrast acquisition in 7/8 horses with paranasal sinus cysts. A similar wall-like structure was detected in 3/10 horses with other sinus diseases, however, in contrast to horses with paranasal sinus cysts, two of these also had hyperattenuating regions within the contents of the sinus lesion. Bone destruction and formation affecting cancellous and cortical bone and dental disease were frequent in horses with paranasal sinus cysts. No significant difference in attenuation values was found when the fluid/soft tissue attenuation contents of lesions in horses with paranasal sinus cysts (mean 28.9 ± SD 9.2 HU) were compared with other sinus diseases when ethmoid haematomas were excluded (30.4 ± 12.9 HU, P = .8). MAIN LIMITATIONS: Low number of cases. CONCLUSIONS: Detection of a hyperattenuating cystic wall is a helpful feature for identifying paranasal sinus cysts in CT images of horses. In contrast, measurement of attenuation values of the soft tissue/fluid contents of the sinus lesions was not helpful in identifying paranasal sinus cysts.

Nursing and training of pigs used in renal transplantation studies.

The pig is commonly used in renal transplantation studies since the porcine kidney resembles the human kidney. To meet the requirements of intense caretaking and examination without stress, a 2-week socialisation and training programme was developed. Conventional cross-breed pigs (n = 36) with high health status were trained for 15 min/day in a four-step training programme before kidney transplantation. The systematic training resulted in calm animals, which allowed for ultrasound examination, blood sampling and urine sampling without restraint. When a 2-methacryloyloxyethyl phosphorylcholine polymer-coated jugular catheter introduced via the auricular vein was used for post-operative blood sampling, clotting was avoided. To assess renal function, urinary output was observed and creatinine and cystatin C were measured; the latter was not found to be useful in recently transplanted pigs. The results presented contribute to the 3Rs (refine, reduce, replace).

Multiple genomic aberrations in a patient with mental retardation and hypogonadism: 45,X/46,X,psu dic(Y) karyotype, thyroid hormone receptor beta (THRB) mutation and heterozygosity for Wilson disease.

We report on multiple genomic aberrations in a patient with mental retardation. In addition, he had hypogonadism, elevated thyroid hormone levels, hearing loss, delayed speech development and mild dysmorphic features. First, we identified a mosaic karyotype, 45,X/46,X,psu dic(Y). The pseudo-dicentric Y chromosome has three short arm segments. Second, we found a germline mutation (Pro453Thr) of the thyroid hormone receptor beta (THRB) which is associated with resistance to thyroid hormone. Third, he was found to be a carrier of a heterozygous ATP7B mutation (c.2575 + 5G > C), the Wilson disease gene. Even though an array-CGH (with a density of approximately 1 Mb) did not reveal any further genomic gains or losses, we cannot exclude that all contributing factors have been identified. However, this case report shows that with increasing technological possibilities we can find more than one cause for developmental problems in a single patient. The identification of multiple causes in a single patient may complicate explaining the disorder and genetic counseling.

Comparison of macroscopic resorption time for a self-locking device and suture material in ovarian pedicle ligation in dogs.

A resorbable self-locking device (LigaTie) was developed to enable safe and easy surgical ligation of blood vessels. The aim of this study was to compare the long-term in vivo resorption of the device to a commercially available suture of equivalent material (Maxon) following ovarian pedicle ligation. After ovariohysterectomy follow-up ultrasound examinations were performed monthly on 21 dogs ligated with the device and 22 dogs ligated with the suture material until no hyperechoic remnants, acoustic shadowing or local tissue reactions were detected. In both groups, the ovarian pedicles gradually decreased in size. Ligation material was considered macroscopically resorbed when ultrasound showed no signs of the device or suture, ovarian pedicle or tissue reaction. Macroscopic resorption had occurred without signs of complications and was complete by four months for sutures and 5.5 months for the device. The results show that resorption time in vivo for the resorbable self-locking device is mildly longer than suture of the same material and that no complications of device resorption were detected, supporting that the resorbable self-locking device is safe for in vivo use.

Radiographic and ultrasonographic findings in a dog with emphysematous pyometra.

BACKGROUND: Emphysematous pyometra is a rare canine disease characterized by gas-forming bacteria infecting the uterus and causing an accumulation of both gas and infectious exudate in the uterine lumen. While radiological features of emphysematous pyometra have been previously described in dogs, the ultrasonographic appearance has not been reported. CASE PRESENTATION: A 7-year-old intact female Labrador Retriever was presented because of a 1 day history of vomiting, anorexia, mild polyuria/polydipsia and signs of fatigue. On physical examination the dog had a swollen vulva with a sparse amount of yellow discharge. Lateral and ventrodorsal radiographs showed a dilated predominantly gas-filled tubular structure located in the mid and cranial abdomen traversing from left to right and ending dorsally at the level of the 12th thoracic vertebra. A small intestinal ileus was initially suspected. Following the radiographic examination, abdominal ultrasound was performed. In the left mid and caudal abdomen there were two thin-walled gas-containing tubular structures. One had the typical layered appearance of an intestinal wall and represented the descending colon. The second structure had a similar thickness but homogenously hypoechoic wall and contained gas and echogenic fluid in the lumen. By use of several positional changes of the dog aiming to alter the location of the intraluminal gas, the second structure was traced to the right ovary cranially and the uterine body caudally, confirming that the structure was the right uterine horn. A final diagnosis of emphysematous pyometra was made. CONCLUSION: Ultrasound can be used as a non-invasive diagnostic method to differentiate between small intestinal ileus and emphysematous pyometra.

Ring chromosome formation as a novel escape mechanism in patients with inverted duplication and terminal deletion.

Ring chromosomes are rare cytogenetic findings and are associated at phenotypic level with mental retardation and congenital abnormalities. Features specific for ring chromosome syndromes often overlap with the features of terminal deletions for the corresponding chromosomes. Here, we report a case of a ring chromosome 14 which was identified by conventional cytogenetics and shown to have a terminal deletion and an additional inverted duplication with a triplication by using large insert clone and oligo array-comparative genomic hybridization (array-CGH), fluorescence in situ hybridization (FISH) and multiplex ligation-dependent probe amplification (MLPA). The combination of an inverted duplication with a terminal deletion in a ring chromosome is of special interest for the described syndromes of chromosome 14. The presented findings might explain partly overlapping clinical features described in terminal deletion, duplication and ring chromosome 14 cases, as these rearrangements can be easily overlooked when performing GTG-banding only. Furthermore, we suggest that ring chromosome formation can act as an alternative chromosome rescue next to telomere healing and capture, particularly for acrocentric chromosomes. To our knowledge, this is the first time an inverted duplication with a terminal deletion in a ring chromosome is identified and characterized using high-resolution molecular karyotyping. Systematic evaluation of ring chromosomes by array-CGH might be especially useful in distinguishing cases with a duplication/deletion from those with a deletion only.

Postoperative computed tomography and low-field magnetic resonance imaging findings in dogs with degenerative lumbosacral stenosis treated by dorsal laminectomy.

OBJECTIVES: To describe postoperative computed tomography (CT) and magnetic resonance imaging (MRI) findings in dogs with degenerative lumbosacral stenosis (DLSS) treated by dorsal laminectomy and partial discectomy. METHODS: Prospective clinical case study of dogs diagnosed with and treated for DLSS. Surgical and clinical findings were described. Computed tomography and low field MRI findings pre- and postoperatively were described and graded. Clinical, CT and MRI examinations were performed four to 18 months after surgery. RESULTS: Eleven of 13 dogs were clinically improved and two dogs had unchanged clinical status postoperatively despite imaging signs of neural compression. Vacuum phenomenon, spondylosis, sclerosis of the seventh lumbar (L7) and first sacral (S1) vertebrae endplates and lumbosacral intervertebral joint osteoarthritis became more frequent in postoperative CT images. Postoperative MRI showed mild disc extrusions in five cases, and in all cases contrast enhancing non-discal tissue was present. All cases showed contrast enhancement of the L7 spinal nerves both pre- and postoperatively and seven had contrast enhancement of the lumbosacral intervertebral joints and paraspinal tissue postoperatively. Articular process fractures or fissures were noted in four dogs. CLINICAL SIGNIFICANCE: The study indicates that imaging signs of neural compression are common after DLSS surgery, even in dogs that have clinical improvement. Contrast enhancement of spinal nerves and soft tissues around the region of disc herniation is common both pre- and postoperatively and thus are unreliable criteria for identifying complications of the DLSS surgery.

High-frequency ultrasound of Peyer's patches in the small intestine of young cats.

OBJECTIVES: A previously unreported, asymmetrically positioned hypoechoic extra layer (APHEL) in the submucosa of the feline distal jejunum and ileum has been recognised using high-frequency ultrasound. The objectives of this study were to characterise the APHEL histologically, and to describe the prevalence and ultrasonographic features of the APHEL in a population of clinically healthy young cats. METHODS: In an anatomical study, two cats were autopsied and histopathology of the small intestine was performed. An APHEL was detected with ultrasound in the distal jejunum and ileum ante-mortem in the first cat and post mortem in the second cat. Samples for histopathology were obtained from these areas. In the second, prospective part of the study, to document the presence or absence of an APHEL, high-frequency (18 MHz) ultrasound was performed of the intestinal tract in 20 other cats. These cats were client-owned cats aged 6-18 months presented for neutering. The cats were included in the study based on a normal clinical examination, lack of previous or concurrent signs of disease, and having no abnormalities detected at abdominal ultrasound. RESULTS: Histopathology from the distal jejunum and ileum in the two cats in the anatomical part of the study showed that the APHEL represented asymmetrically positioned normal lymphatic tissue (Peyer's patches) in the lamina propria and submucosa. In the second part of the study, an APHEL was identified in the submucosa of the distal part of the jejunum and ileum in all 20 cats. Additionally, a similar layer could also be seen further proximally in the jejunum in 10 (50%) of the cats. The thickness of the APHEL was 1.0 mm in both jejunum and ileum. CONCLUSIONS AND RELEVANCE: Presumed normal lymphatic tissue in the small intestinal submucosa can be seen with high-frequency ultrasound and is a common finding in young cats.

Online dosimetry for temoporfin-mediated interstitial photodynamic therapy using the canine prostate as model.

Online light dosimetry with real-time feedback was applied for temoporfin-mediated interstitial photodynamic therapy (PDT) of dog prostate. The aim was to investigate the performance of online dosimetry by studying the correlation between light dose plans and the tissue response, i.e., extent of induced tissue necrosis and damage to surrounding organs at risk. Light-dose planning software provided dose plans, including light source positions and light doses, based on ultrasound images. A laser instrument provided therapeutic light and dosimetric measurements. The procedure was designed to closely emulate the procedure for whole-prostate PDT in humans with prostate cancer. Nine healthy dogs were subjected to the procedure according to a light-dose escalation plan. About 0.15 mg/kg temoporfin was administered 72 h before the procedure. The results of the procedure were assessed by magnetic resonance imaging, and gross pathology and histopathology of excised tissue. Light dose planning and online dosimetry clearly resulted in more focused effect and less damage to surrounding tissue than interstitial PDT without dosimetry. A light energy dose-response relationship was established where the threshold dose to induce prostate gland necrosis was estimated from 20 to 30 J/cm2.

Vasopressin, cortisol, and catecholamine concentrations in dogs with dilated cardiomyopathy.

OBJECTIVE: To evaluate plasma concentrations and urinary excretion of vasopressin and cortisol and urinary excretion of catecholamines in dogs with dilated cardiomyopathy (DCM). ANIMALS: 15 dogs with clinical signs of DCM, 15 dogs with preclinical DCM, and 15 control dogs. PROCEDURE: Physical examinations, thoracic radiography, ECG, and echocardiography were performed on all dogs. Blood and urine samples were collected. RESULTS: Plasma concentration of vasopressin and the urine cortisol-to-urine creatinine ratio were significantly increased in dogs with clinical signs of DCM and dogs with preclinical DCM, compared with control dogs. Plasma vasopressin concentration was significantly higher in dogs with clinical signs of DCM, compared with dogs with preclinical DCM. Urine vasopressin-to-urine creatinine ratio was significantly increased in dogs with clinical signs of DCM, compared with dogs with preclinical DCM and control dogs. Urine epinephrine-to-urine creatinine ratio and urine norepinephrine-to-urine creatinine ratio were significantly increased in dogs with clinical signs of DCM, compared with control dogs. Plasma concentration of cortisol and urine dopamine-to-urine creatinine ratio did not differ significantly among groups. CONCLUSIONS AND CLINICAL RELEVANCE: According to this study, the neuroendocrine pattern is changed in dogs with preclinical DCM. These changes are even more pronounced in dogs with clinical signs of DCM. Analysis of concentrations of vasopressin, cortisol, and catecholamines may aid in identification of the clinical stages of DCM. These findings may also provide a basis for additional studies of the possible beneficial effects of vasopressin antagonists and beta-adrenergic receptor antagonists in the treatment of dogs with congestive heart failure and DCM.