RESUMEN
Ligneous membranitis/conjunctivitis (LM, OMIM 217090) is a hereditary disorder caused by a congenital plasminogen (PLG) deficiency. In veterinary medicine, LM (OMIA 002020-9615) has rarely been reported in Golden Retrievers, Yorkshire Terriers, Doberman Pinschers and Scottish Terriers. In the latter breed, an A>T variation in an intron donor site of the PLG gene (PLG, c.1256+2T>A) has been found to be the sole causative molecular defect reported to date in dogs. Owing to the absence of plasmin enzymatic clearance which in turn depends on the lack of its proenzyme plasminogen, fibrin deposits tend to accumulate in viscous membranes on the eyes, triggering and sustaining an intense inflammatory response. A case of LM was diagnosed in a 7-month-old male Maltese dog. The dog was examined for severe recurrent conjunctivitis. A diagnosis of ligneous conjunctivitis was made by an ophthalmologist after a thorough eye examination and was confirmed by a complete lack of plasma activity of plasminogen. The main local signs were redness of the conjunctiva with persistent membranes having ligneous (wood-like) membranes on the eyes. The disease was associated with a complex rearrangement involving the plasminogen gene loci, causing the complete deletion of exon 1. This study provides a spontaneous animal model for LM associated with complete plasminogen deficiency and provides a method for detecting affected or carrier dogs.
Asunto(s)
Conjuntivitis/veterinaria , Enfermedades de los Perros/genética , Perros/genética , Plasminógeno/deficiencia , Enfermedades Cutáneas Genéticas/veterinaria , Animales , Cruzamiento , Conjuntivitis/genética , Masculino , Plasminógeno/genética , Enfermedades Cutáneas Genéticas/genéticaRESUMEN
Epilepsy is the most common chronic neurological disorder in dogs. Approximately 20-30% of dogs do not achieve satisfactory seizure control with two or more anti-epileptic drugs at appropriate dosages. This condition, defined as refractory epilepsy, is a multifactorial condition involving both acquired and genetic factors. The P glycoprotein might play and important role in the pathophysiological mechanism and it is encoded by the ABCB1 gene. An association between a single nucleotide variation of the ABCB1 gene (c.-6-180T>G) and phenobarbital resistance has previously been reported in a Border collie population with idiopathic epilepsy. To date, the presence and relevance of this polymorphism has not been assessed in other breeds. A multicentre retrospective, case-control study was conducted to investigate associations between ABCB1 c.-6-180T>G, clinical variables, and refractoriness in a multi-breed population of dogs with refractory idiopathic epilepsy. A secondary aim was to evaluate the possible involvement of the ABCB1 c.-6-180T>G single nucleotide variation this population. Fifty-two refractory and 50 responsive dogs with idiopathic epilepsy were enrolled. Of these, 45 refractory and 50 responsive (control) dogs were genotyped. The G allele was found in several breeds, but there was no evidence of association with refractoriness (P=0.69). The uncertain role of the c.-6-180T>G variation was further suggested by an association between the T/T genotype with both refractoriness and responsiveness in different breeds. Furthermore, high seizure density (cluster seizure) was the main clinical risk factor for refractory idiopathic epilepsy (P=0.003).
Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Enfermedades de los Perros/genética , Epilepsia Refractaria/veterinaria , Polimorfismo de Nucleótido Simple , Animales , Estudios de Casos y Controles , Estudios de Cohortes , Perros , Epilepsia Refractaria/genética , Femenino , Italia , Masculino , Linaje , Estudios Retrospectivos , Factores de RiesgoRESUMEN
Degenerative myelopathy is a severe and progressive neurodegenerative disease and, in the majority of breeds, is associated with the c.118G>A substitution in exon 2 of the canine superoxide dismutase 1 (SOD1) gene. Our laboratories have been engaged in determining the cause of many discordant findings between the parental and the offspring genotypes found by different laboratories. In both cases, the discordant findings refer to actual heterozygous dogs that had been typed as homozygous for the variant allele. To that aim, the genomic context of the causative variant was investigated in two Hovawart dogs. An insertion of 54 nucleotides composed of a poly-T stretch and 15 nucleotides containing the duplication of the exon 2-intron 2 junction was found. The insertion was responsible for the partial mismatch of the reverse primer used for a direct sequencing assay. The mismatch hampered the amplification of the corresponding allele and caused an evident drop-out effect. The insertion is in complete linkage disequilibrium with the c.118G allele. The allele containing the insertion was highly prevalent in Hovawart dogs, accounting for the 26.6% of allele frequency. The insertion was also found in other unrelated breeds such as Rough Collies and Standard Poodles. In conclusion, the study illustrates the importance of correctly designing the primers to avoid inaccurate genotyping of the degenerative myelopathy causative variant in exon 2 of the SOD1 gene.
Asunto(s)
Enfermedades de los Perros/genética , Perros/genética , Enfermedades Neurodegenerativas/veterinaria , Enfermedades de la Médula Espinal/veterinaria , Superóxido Dismutasa-1/genética , Alelos , Animales , Cruzamiento , Frecuencia de los Genes , Genotipo , Técnicas de Genotipaje , Homocigoto , Intrones , Desequilibrio de Ligamiento , Mutagénesis Insercional , Enfermedades Neurodegenerativas/genética , Enfermedades de la Médula Espinal/genéticaRESUMEN
OBJECTIVES: This study aimed to evaluate the agreement between microscopic and molecular testing for differentiating feline intestinal bowel disease and small cell alimentary lymphoma in duodenal endoscopic biopsies. METHODS: Four different diagnostic methods (cytology, histology, immunohistochemistry and clonality) were sequentially applied to 77 cases of feline chronic enteropathies. The agreement between the different diagnostic methods was calculated and survival data were obtained to assess the most reliable method for predicting outcome. RESULTS: Seventy-seven cases were included in the study. On multivariate survival analysis, only the clonality-based diagnosis of lymphoma was significantly associated with poor survival, with a risk of enteropathy-related death 2·8 times higher. By comparing the other tests with clonality, specificity was high (87 to 97%), whereas sensitivity was 36·8% for cytology, 39·5% for histology, 63·2% for immunohistochemistry, resulting in an overall accuracy of 62·3, 68·8 and 80·5%, respectively. CLINICAL SIGNIFICANCE: Clonality analysis can consistently increase the possibility of correctly and early diagnosing small cell lymphoma on endoscopic biopsies. Histological suspicion of alimentary lymphoma, even if not confirmed by clonality, should never be ignored, as it may represent a debutant form of lymphoma or it may later progress to lymphoma.
Asunto(s)
Enfermedades de los Gatos/diagnóstico , Enfermedades Inflamatorias del Intestino/veterinaria , Neoplasias Intestinales/veterinaria , Linfoma/veterinaria , Animales , Enfermedades de los Gatos/patología , Gatos , Diagnóstico Diferencial , Duodenoscopía/veterinaria , Duodeno/patología , Femenino , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/patología , Neoplasias Intestinales/diagnóstico , Neoplasias Intestinales/patología , Linfoma/diagnóstico , Linfoma/patología , Masculino , Sensibilidad y Especificidad , Manejo de EspecímenesRESUMEN
Equine ileocolonic aganglionosis, which is also called lethal white foal syndrome (LWFS), is a severe congenital condition characterized by the unsuccessful colonization of neural crest progenitors in the caudal part of the small intestine and the entire large intestine. LWFS, which is attributable to a mutation in the endothelin receptor B gene, is the horse equivalent of Hirschsprung's disease in humans. Affected foals suffer from aganglionosis or hypoganglionosis of the enteric ganglia resulting in intestinal akinesia and colic. In other species with aganglionosis, fibers of extrinsic origin show an abnormal distribution pattern within the gut wall, but we have no information to date regarding this occurrence in horses. Our present aim is to investigate the distribution of extrinsic sympathetic and sensory neural fibers in LWFS, focusing on ileum and the pelvic flexure of the colon of two LWFS foals compared with a control subject. The sympathetic fibers were immunohistochemically identified with the markers tyrosine hydroxylase and dopamine beta-hydroxylase. The extrinsic sensory fibers were identified with the markers Substance P (SP) and calcitonin gene-related peptide (CGRP). Since SP and CGRP are also synthesized by subclasses of horse intramural neurons, LWFS represents a good model for the selective study of extrinsic fiber distribution. Affected foals showed large bundles of extrinsic fibers, compared with the control, as observed in Hirschsprung's disease. Furthermore, altered adrenergic pathways were observed, prominently in the pelvic flexure. The numbers of SP- and CGRP-immunoreactive fibers in the muscle, a target of enteric neurons, were dramatically reduced, whereas fibers deduced to be extrinsic sensory axons persisted around submucosal blood vessels. Fiber numbers in the mucosa were reduced. Thus, extrinsic innervation, contributing to modulate enteric functions, might also be affected during LWFS.
Asunto(s)
Enfermedad de Hirschsprung/patología , Enfermedades de los Caballos/patología , Íleon/inervación , Íleon/patología , Pelvis/inervación , Pelvis/patología , Animales , Péptido Relacionado con Gen de Calcitonina/metabolismo , Caballos , Masculino , Tirosina 3-Monooxigenasa/metabolismoRESUMEN
The conventional polymerase chain reaction (PCR)/sequencing methods may be poorly suited for the detection of somatic mutations in canine mast cell tumour (MCT) samples owing to limited sensitivity. This study was aimed at establishing novel and more sensitive methods, assessing their limit of detection and comparing their sensitivity with conventional methods.Two different 'driver' somatic mutations of c-KIT, together with the wild-type counterparts, were cloned in plasmids to prepare standard samples with known concentrations of mutated alleles in a background of wild-type alleles; the plasmids standards were assayed using either conventional or novel, highly sensitive technique. Conventional PCR/sequencing showed a sensitivity of 50-20%. Conversely, all the novel methods obtained higher sensitivities allowed reaching as low as 2.5-1.2% of the mutated DNA.The study demonstrates that early conventional methods could likely have underestimated the prevalence of KIT mutations of MCTs, therefore affecting the assessment of their relevance in prognosis and tyrosine kinase inhibitor (TKI) treatment effectiveness.
Asunto(s)
Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/genética , Sarcoma de Mastocitos/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , Proteínas Proto-Oncogénicas c-kit/genética , Animales , Cromatografía Líquida de Alta Presión/veterinaria , Bases de Datos Genéticas , Perros , Sarcoma de Mastocitos/diagnóstico , Sarcoma de Mastocitos/genética , Mutación , Plásmidos , Reacción en Cadena de la Polimerasa/métodos , Polimorfismo Genético , Pronóstico , Proteínas Proto-Oncogénicas c-kit/análisis , Sensibilidad y EspecificidadRESUMEN
Feline cutaneous mast cell tumors (FeCMCTs) are characterized by variable biological behavior. Development of multiple nodules and potential visceral involvement, along with inconsistency of conventional prognostic aids, justify uncertainty in differentiating benign from malignant forms. c-Kit proto-oncogene activating mutations have been reported in feline mast cell tumors (MCTs), but their prognostic relevance was not investigated. This study was performed on FeCMCTs with variable clinical outcome to assess whether Kit cytoplasmic immunohistochemical labeling can be regarded as indicative of c-Kit mutations and to evaluate the relationship between Kit dysregulation and survival. Twenty-four cats diagnosed with a primary cutaneous MCT were enrolled. Kit immunohistochemical pattern and c-Kit (exons 8, 9, 11) mutational status were assessed in 34 tumor samples. Risk factors affecting survival were a number of mitoses greater than 5 per 10 HPFs (P = .017) and cytoplasmic Kit labeling (P = .045). Increased mitotic activity was associated with Kit cytoplasmic expression (P = .01). c-Kit encoding mutations were present in 19 (56%) tumors (exon 8, 19%; exon 9, 71%; exon 11, 10%), however, they were not significantly related to protein expression and they had no influence on prognosis. Additionally, in 6 of 9 (67%) cats, multiple nodules from the same cat had different mutational statuses. Mutations in the fifth immunoglobulin-like domain of Kit occur frequently in FeCMCT, but they are variably associated with aberrant protein expression and do not appear to be strictly correlated with biological behavior. These findings need to be confirmed in larger series, and exploration of further genomic regions of c-Kit is warranted.
Asunto(s)
Enfermedades de los Gatos/enzimología , Enfermedades de los Gatos/metabolismo , Regulación Enzimológica de la Expresión Génica/fisiología , Regulación Neoplásica de la Expresión Génica/fisiología , Mastocitosis Cutánea/veterinaria , Proteínas Proto-Oncogénicas c-kit/metabolismo , Animales , Gatos , Análisis Mutacional de ADN/veterinaria , Técnicas Histológicas/veterinaria , Inmunohistoquímica/veterinaria , Italia , Mastocitosis Cutánea/enzimología , Mastocitosis Cutánea/metabolismo , Curva ROCRESUMEN
Gastrointestinal stromal tumours (GISTs) represent a distinctive group of primary mesenchymal tumours of the gastrointestinal tract identified immunohistochemically by expression of CD117. A 10-year-old neutered female domestic shorthair cat with a history of recurrent vomiting was examined. The presence of a gastric mass was recognized and a laparotomy was performed. Cytological examination was consistent with a low-grade malignant mesenchymal tumour and histopathological investigation suggested myogenic differentiation of tumour cells. The diagnosis of GIST was confirmed by immunohistochemical expression of CD117. Sequence analysis of the KIT gene identified a deletion in exon 11. The same mutation is found often in human GISTs.
Asunto(s)
Enfermedades de los Gatos/genética , Enfermedades de los Gatos/patología , Tumores del Estroma Gastrointestinal/veterinaria , Proteínas Proto-Oncogénicas c-kit/genética , Neoplasias Gástricas/veterinaria , Animales , Gatos , Análisis Mutacional de ADN , Tumores del Estroma Gastrointestinal/genética , Tumores del Estroma Gastrointestinal/patología , Inmunohistoquímica , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologíaAsunto(s)
Enfermedades de los Perros/genética , Repeticiones de Microsatélite/genética , Degeneración Retiniana/veterinaria , Retinitis Pigmentosa/genética , Animales , Secuencia de Bases , Biología Computacional , Cartilla de ADN , Bases de Datos de Ácidos Nucleicos , Perros , Humanos , Datos de Secuencia Molecular , Técnicas de Amplificación de Ácido Nucleico , Degeneración Retiniana/genética , Análisis de Secuencia de ADNRESUMEN
Retroperitoneal bleeding from splenic rupture occurred after initially uneventful arthroscopy. The diagnosis was finally set up in CT-scan, whilst peritoneal lavage was negative. Since there was no incidence of previous abdominal trauma and no abnormal findings in histology, spontaneous perioperative splenic rupture has been discussed.
Asunto(s)
Artroscopía/efectos adversos , Traumatismos de la Rodilla/diagnóstico , Rotura del Bazo/etiología , Humanos , Masculino , Persona de Mediana Edad , Esplenectomía , Rotura del Bazo/cirugíaRESUMEN
The applicability of whole-cell protein patterns obtained by sodium dodecylsulfate-polyacrylamide gel electrophoresis as a typing method for Clostridium difficile was examined using a total of 227 strains isolated from 191 patients and their surroundings. Computer-aided densitometric analysis was used to establish a reliable standardization technique with which a large number of protein patterns could be efficiently classified. The normalized tracks could be electronically superimposed and compared to give reproducible results. The influence of sample preparation for electrophoresis was found to be negligible. By this technique 35 subgroups could be differentiated, and further discrimination was possible within each subgroup using minor, even very weak protein bands. Epidemiologically related strains of Clostridium difficile yielded absolutely identical patterns, allowing unequivocal identification. Thus protein electrophoresis combined with densitometric analysis was shown to be useful for typing Clostridium difficile isolates.