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1.
PLoS Genet ; 14(12): e1007850, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30521570

RESUMO

Domestic dog breeds exhibit remarkable morphological variations that result from centuries of artificial selection and breeding. Identifying the genetic changes that contribute to these variations could provide critical insights into the molecular basis of tissue and organismal morphogenesis. Bulldogs, French Bulldogs and Boston Terriers share many morphological and disease-predisposition traits, including brachycephalic skull morphology, widely set eyes and short stature. Unlike other brachycephalic dogs, these breeds also exhibit vertebral malformations that result in a truncated, kinked tail (screw tail). Whole genome sequencing of 100 dogs from 21 breeds identified 12.4 million bi-allelic variants that met inclusion criteria. Whole Genome Association of these variants with the breed defining phenotype of screw tail was performed using 10 cases and 84 controls and identified a frameshift mutation in the WNT pathway gene DISHEVELLED 2 (DVL2) (Chr5: 32195043_32195044del, p = 4.37 X 10-37) as the most strongly associated variant in the canine genome. This DVL2 variant was fixed in Bulldogs and French Bulldogs and had a high allele frequency (0.94) in Boston Terriers. The DVL2 variant segregated with thoracic and caudal vertebral column malformations in a recessive manner with incomplete and variable penetrance for thoracic vertebral malformations between different breeds. Importantly, analogous frameshift mutations in the human DVL1 and DVL3 genes cause Robinow syndrome, a congenital disorder characterized by similar craniofacial, limb and vertebral malformations. Analysis of the canine DVL2 variant protein showed that its ability to undergo WNT-induced phosphorylation is reduced, suggesting that altered WNT signaling may contribute to the Robinow-like syndrome in the screwtail breeds.


Assuntos
Anormalidades Craniofaciais/veterinária , Proteínas Desgrenhadas/genética , Doenças do Cão/genética , Cães/genética , Nanismo/veterinária , Deformidades Congênitas dos Membros/veterinária , Anormalidades Urogenitais/veterinária , Sequência de Aminoácidos , Animais , Anormalidades Craniofaciais/genética , Anormalidades Craniofaciais/metabolismo , Proteínas Desgrenhadas/metabolismo , Doenças do Cão/metabolismo , Cães/anatomia & histologia , Cães/classificação , Nanismo/genética , Nanismo/metabolismo , Feminino , Mutação da Fase de Leitura , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Deformidades Congênitas dos Membros/genética , Deformidades Congênitas dos Membros/metabolismo , Masculino , Compostos de Organossilício , Homologia de Sequência de Aminoácidos , Especificidade da Espécie , Cauda/anatomia & histologia , Anormalidades Urogenitais/genética , Anormalidades Urogenitais/metabolismo , Via de Sinalização Wnt/genética
2.
Proc Natl Acad Sci U S A ; 114(43): 11476-11481, 2017 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-29073074

RESUMO

Chondrodystrophy in dogs is defined by dysplastic, shortened long bones and premature degeneration and calcification of intervertebral discs. Independent genome-wide association analyses for skeletal dysplasia (short limbs) within a single breed (PBonferroni = 0.01) and intervertebral disc disease (IVDD) across breeds (PBonferroni = 4.0 × 10-10) both identified a significant association to the same region on CFA12. Whole genome sequencing identified a highly expressed FGF4 retrogene within this shared region. The FGF4 retrogene segregated with limb length and had an odds ratio of 51.23 (95% CI = 46.69, 56.20) for IVDD. Long bone length in dogs is a unique example of multiple disease-causing retrocopies of the same parental gene in a mammalian species. FGF signaling abnormalities have been associated with skeletal dysplasia in humans, and our findings present opportunities for both selective elimination of a medically and financially devastating disease in dogs and further understanding of the ever-growing complexity of retrogene biology.


Assuntos
Doenças do Cão/genética , Fator 4 de Crescimento de Fibroblastos/genética , Degeneração do Disco Intervertebral/veterinária , Deslocamento do Disco Intervertebral/veterinária , Osteocondrodisplasias/veterinária , Animais , Cães , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Degeneração do Disco Intervertebral/genética , Deslocamento do Disco Intervertebral/genética , Mutagênese Insercional , Osteocondrodisplasias/genética
3.
Vet Surg ; 45(3): 309-18, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27007649

RESUMO

OBJECTIVE: To compare the stiffness, angular deformation, and mode of failure of lumbar vertebral column constructs stabilized with bilateral pins and polymethylmethacrylate (Pin-PMMA) or with a unilateral (left) locking compression plate (LCP) with monocortical screws. STUDY DESIGN: Ex vivo biomechanical, non-randomized. SAMPLES: Cadaveric canine thoracolumbar specimens (n=16). METHODS: Thoracolumbar (T13-L3) vertebral specimens had the L1-L2 vertebral motion unit stabilized with either Pin-PMMA or LCP. Stiffness in flexion, extension, and right and left lateral bending after nondestructive testing were compared between intact (pretreated) specimens and Pin-PMMA, and LCP constructs. The Pin-PMMA and LCP constructs were then tested to failure in flexion and left lateral bending. RESULTS: Both the Pin-PMMA and LCP constructs had reduced range of motion at the stabilized L1-L2 vertebral motion unit compared to intact specimens. The Pin-PMMA constructs had less range of motion for the flexion elastic zone than LCP constructs. The Pin-PMMA constructs were stiffer than intact specimens in flexion, extension, and lateral bending, and stiffer than LCP constructs in flexion and left lateral bending. The Pin-PMMA constructs had less angular deformation at construct yield and lower residual deformation at L1-L2 than LCP constructs after destructive testing to failure in flexion. The Pin-PMMA constructs were stiffer, stronger, and had less deformation at yield than LCP constructs after destructive testing to failure in lateral bending. Most constructs failed distant to the implant and fixation site. CONCLUSIONS: Pin-PMMA constructs had greater lumbar vertebral stiffness and reduced ROM than LCP constructs; however, both Pin-PMMA and LCP constructs were stronger than intact specimens.


Assuntos
Pinos Ortopédicos/veterinária , Placas Ósseas/veterinária , Cães/lesões , Vértebras Lombares/lesões , Fraturas da Coluna Vertebral/veterinária , Animais , Fenômenos Biomecânicos , Cães/cirurgia , Vértebras Lombares/cirurgia , Polimetil Metacrilato , Amplitude de Movimento Articular , Fraturas da Coluna Vertebral/cirurgia
4.
Anim Genet ; 46(6): 711-5, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26374066

RESUMO

Some Devon Rex and Sphynx cats have a variably progressive myopathy characterized by appendicular and axial muscle weakness, megaesophagus, pharyngeal weakness and fatigability with exercise. Muscle biopsies from affected cats demonstrated variable pathological changes ranging from dystrophic features to minimal abnormalities. Affected cats have exacerbation of weakness following anticholinesterase dosing, a clue that there is an underlying congenital myasthenic syndrome (CMS). A genome-wide association study and whole-genome sequencing suggested a causal variant for this entity was a c.1190G>A variant causing a cysteine to tyrosine substitution (p.Cys397Tyr) within the C-terminal domain of collagen-like tail subunit (single strand of homotrimer) of asymmetric acetylcholinesterase (COLQ). Alpha-dystroglycan expression, which is associated with COLQ anchorage at the motor end-plate, has been shown to be deficient in affected cats. Eighteen affected cats were identified by genotyping, including cats from the original clinical descriptions in 1993 and subsequent publications. Eight Devon Rex and one Sphynx not associated with the study were identified as carriers, suggesting an allele frequency of ~2.0% in Devon Rex. Over 350 tested cats from other breeds did not have the variant. Characteristic clinical features and variant presence in all affected cats suggest a model for COLQ CMS. The association between the COLQ variant and this CMS affords clinicians the opportunity to confirm diagnosis via genetic testing and permits owners and breeders to identify carriers in the population. Moreover, accurate diagnosis increases available therapeutic options for affected cats based on an understanding of the pathophysiology and experience from human CMS associated with COLQ variants.


Assuntos
Acetilcolinesterase/genética , Doenças do Gato/genética , Gatos/genética , Colágeno/genética , Proteínas Musculares/genética , Síndromes Miastênicas Congênitas/genética , Animais , Cruzamento , Frequência do Gene , Estudo de Associação Genômica Ampla , Genótipo , Análise de Sequência de DNA
5.
Vet Radiol Ultrasound ; 54(3): 271-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23521525

RESUMO

Magnetic resonance (MR) imaging characteristics of intracranial granular cell tumors (GCTs) have been previously reported in three dogs. The goal of this retrospective study was to examine a larger number of dogs and determine whether distinctive MR characteristics of intracranial GCTs could be identified. Six dogs with histologically confirmed intracranial GCTs and MR imaging were included. Tumor location, size, mass effect, T1- and T2-weighted signal intensity, and peritumoral edema MR characteristics were recorded. In all dogs, GCTs appeared as well-defined, extra-axial masses with a plaque-form, sessile distribution involving the meninges. All tumors were located along the convexity of the cerebrum, the falx cerebri, or the ventral floor of the cranial vault. All tumors were mildly hyperintense on T1-weighted images, and iso- to hyperintense on T2-weighted images. A moderate-to-severe degree of peritumoral edema and mass effect were evident in all dogs. Findings indicated that, while several MR imaging characteristics were consistently identified in canine cerebral GCTs, none of these characteristics were unique or distinctive for this tumor type alone.


Assuntos
Neoplasias Encefálicas/veterinária , Encéfalo/patologia , Doenças do Cão/diagnóstico , Tumor de Células Granulares/veterinária , Animais , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patologia , California , Doenças do Cão/patologia , Cães , Feminino , Tumor de Células Granulares/diagnóstico , Tumor de Células Granulares/patologia , Imageamento por Ressonância Magnética/veterinária , Masculino , Estudos Retrospectivos
6.
J Zoo Wildl Med ; 44(4): 1068-74, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24450071

RESUMO

A 25-yr-old spayed female spotted hyena (Crocuta crocuta) developed intermittent right pelvic limb lameness that persisted following conservative medical therapy. No obvious musculoskeletal lesions were noted on initial physical exam; however, spinal radiography was suspicious for possible intervertebral degenerative joint disease or discospondylitis. Despite prolonged medical therapy, the lameness progressed to minimal weight bearing and marked muscle atrophy of the right pelvic limb. Electromyography showed spontaneous activity in the muscles of right sciatic nerve distribution. Sensory and motor nerve conduction velocities in the right tibial and peroneal nerves were undetectable and markedly reduced, respectively. A magnetic resonance imaging (MRI) scan revealed a large, space-occupying mass on the right side of the sacrum and pelvis. Antemortem fine-needle aspiration of the mass and postmortem histopathology resulted in diagnosis of a high-grade squamous cell carcinoma of the anal sac. Squamous cell carcinoma of the anal sac is very rare in domestic dogs and previously unreported in spotted hyenas.


Assuntos
Neoplasias das Glândulas Anais/diagnóstico , Sacos Anais/patologia , Carcinoma de Células Escamosas/veterinária , Hyaenidae , Neoplasias das Glândulas Anais/diagnóstico por imagem , Animais , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/diagnóstico por imagem , Feminino , Radiografia
7.
Brain Commun ; 4(3): fcac115, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35755635

RESUMO

Early implantable epilepsy therapy devices provided open-loop electrical stimulation without brain sensing, computing, or an interface for synchronized behavioural inputs from patients. Recent epilepsy stimulation devices provide brain sensing but have not yet developed analytics for accurately tracking and quantifying behaviour and seizures. Here we describe a distributed brain co-processor providing an intuitive bi-directional interface between patient, implanted neural stimulation and sensing device, and local and distributed computing resources. Automated analysis of continuous streaming electrophysiology is synchronized with patient reports using a handheld device and integrated with distributed cloud computing resources for quantifying seizures, interictal epileptiform spikes and patient symptoms during therapeutic electrical brain stimulation. The classification algorithms for interictal epileptiform spikes and seizures were developed and parameterized using long-term ambulatory data from nine humans and eight canines with epilepsy, and then implemented prospectively in out-of-sample testing in two pet canines and four humans with drug-resistant epilepsy living in their natural environments. Accurate seizure diaries are needed as the primary clinical outcome measure of epilepsy therapy and to guide brain-stimulation optimization. The brain co-processor system described here enables tracking interictal epileptiform spikes, seizures and correlation with patient behavioural reports. In the future, correlation of spikes and seizures with behaviour will allow more detailed investigation of the clinical impact of spikes and seizures on patients.

8.
J Vet Intern Med ; 35(3): 1558-1565, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33955582

RESUMO

A 6-year-old neutered male German shepherd dog was evaluated for obtundation, blindness, and bilateral exophthalmos. A magnetic resonance imaging scan of the brain was performed and identified an arteriovenous malformation (AVM) with several feeding arterial branches, and venous drainage through the cavernous sinus. Venous vessels rostral to the AVM were severely distended and extended into the retrobulbar spaces. Liquid embolization by injection of ethylene vinyl alcohol copolymer was performed from access points in the maxillary arteries and internal carotid arteries. No intraprocedural complications were encountered, and the dog was discharged the next day. Bilateral enucleation eventually was performed because of exposure keratopathy. At 31 months post-embolization, owners reported that the dog was doing very well clinically with high activity level and normal appetite, and the dog also appeared to be pain free. Although intracranial AVMs are very rare in companion animals, successful treatment using liquid embolization is possible and should be considered.


Assuntos
Doenças do Cão , Embolização Terapêutica , Malformações Arteriovenosas Intracranianas , Animais , Doenças do Cão/diagnóstico por imagem , Doenças do Cão/terapia , Cães , Embolização Terapêutica/veterinária , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Malformações Arteriovenosas Intracranianas/terapia , Malformações Arteriovenosas Intracranianas/veterinária , Imageamento por Ressonância Magnética/veterinária , Masculino , Polivinil/uso terapêutico
9.
Sci Rep ; 11(1): 24250, 2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34930926

RESUMO

Chronic brain recordings suggest that seizure risk is not uniform, but rather varies systematically relative to daily (circadian) and multiday (multidien) cycles. Here, one human and seven dogs with naturally occurring epilepsy had continuous intracranial EEG (median 298 days) using novel implantable sensing and stimulation devices. Two pet dogs and the human subject received concurrent thalamic deep brain stimulation (DBS) over multiple months. All subjects had circadian and multiday cycles in the rate of interictal epileptiform spikes (IES). There was seizure phase locking to circadian and multiday IES cycles in five and seven out of eight subjects, respectively. Thalamic DBS modified circadian (all 3 subjects) and multiday (analysis limited to the human participant) IES cycles. DBS modified seizure clustering and circadian phase locking in the human subject. Multiscale cycles in brain excitability and seizure risk are features of human and canine epilepsy and are modifiable by thalamic DBS.


Assuntos
Estimulação Encefálica Profunda/métodos , Epilepsia/prevenção & controle , Convulsões/prevenção & controle , Tálamo/fisiologia , Animais , Ritmo Circadiano , Cães , Eletroencefalografia , Humanos , Risco
10.
JFMS Open Rep ; 6(2): 2055116920939479, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32782816

RESUMO

CASE SUMMARY: A 10-year-old Maine Coon cat was presented for acute onset seizures and cerebrothalamic signs. An intracranial mass, suspected to be a meningioma, was diagnosed on MRI and surgically excised. Histopathology appeared consistent with an atypical meningioma. However, following rapid regrowth of the neoplasm, the patient was humanely euthanized 3 months later. On post-mortem histopathology, the neoplasm was diagnosed as a grade III anaplastic gemistocytic astrocytoma. RELEVANCE AND NOVEL INFORMATION: Gemistocytic astrocytomas are rare brain tumors in the feline patient. This case represents the first report of a feline grade III anaplastic gemistocytic astrocytoma in the cerebrum of a cat with surgical excision and recurrence. The challenging nature of ante-mortem diagnosis and the guarded prognosis, despite surgical intervention, are presented in this report.

11.
Brain Commun ; 2(1): fcaa008, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32161910

RESUMO

Advances in ambulatory intracranial EEG devices have enabled objective analyses of circadian and multiday seizure periodicities, and seizure clusters in humans. This study characterizes circadian and multiday seizure periodicities, and seizure clusters in dogs with naturally occurring focal epilepsy, and considers the implications of an animal model for the study of seizure risk patterns, seizure forecasting and personalized treatment protocols. In this retrospective cohort study, 16 dogs were continuously monitored with ambulatory intracranial EEG devices designed for humans. Detailed medication records were kept for all dogs. Seizure periodicity was evaluated with circular statistics methods. Circular non-uniformity was assessed for circadian, 7-day and approximately monthly periods. The Rayleigh test was used to assess statistical significance, with correction for multiple comparisons. Seizure clusters were evaluated with Fano factor (index of dispersion) measurements, and compared to a Poisson distribution. Relationships between interseizure interval (ISI) and seizure duration were evaluated. Six dogs met the inclusion criteria of having at least 30 seizures and were monitored for an average of 65 weeks. Three dogs had seizures with circadian seizure periodicity, one dog had a 7-day periodicity, and two dogs had approximately monthly periodicity. Four dogs had seizure clusters and significantly elevated Fano factor values. There were subject-specific differences in the dynamics of ISI and seizure durations, both within and between lead and clustered seizure categories. Our findings show that seizure timing in dogs with naturally occurring epilepsy is not random, and that circadian and multiday seizure periodicities, and seizure clusters are common. Circadian, 7-day, and monthly seizure periodicities occur independent of antiseizure medication dosing, and these patterns likely reflect endogenous rhythms of seizure risk.

12.
J Vet Intern Med ; 34(2): 828-837, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31919895

RESUMO

BACKGROUND: Histiocytic sarcoma affecting the central nervous system (CNS HS) in dogs may present as primary or disseminated disease, often characterized by inflammation. Prognosis is poor, and imaging differentiation from other CNS tumors can be problematic. OBJECTIVE: To characterize the clinicopathological inflammatory features, breed predisposition, and survival in dogs with CNS HS. ANIMALS: One hundred two dogs with HS, 62 dogs with meningioma. METHODS: Retrospective case series. Records were reviewed for results of cerebrospinal fluid (CSF) analysis, CBC, treatment, and outcome data. RESULTS: Predisposition for CNS HS was seen in Bernese Mountain Dogs, Golden Retrievers, Rottweilers, Corgis, and Shetland Sheepdogs (P ≤ .001). Corgis and Shetland Sheepdogs had predominantly primary tumors; Rottweilers had exclusively disseminated tumors. Marked CSF inflammation was characteristic of primary rather than disseminated HS, and neoplastic cells were detected in CSF of 52% of affected dogs. Increased neutrophil to lymphocyte ratios were seen in all groups relative to controls (P <.008) but not among tumor subtypes. Definitive versus palliative treatment resulted in improved survival times (P < .001), but overall prognosis was poor. CONCLUSIONS AND CLINICAL IMPORTANCE: Clinicopathological differences between primary and disseminated HS suggest that tumor biological behavior and origin may be different. Corgis and Shetland Sheepdogs are predisposed to primary CNS HS, characterized by inflammatory CSF. High total nucleated cell count and the presence of neoplastic cells support the use of CSF analysis as a valuable diagnostic test. Prognosis for CNS HS is poor, but further evaluation of inflammatory mechanisms may provide novel therapeutic opportunities.


Assuntos
Neoplasias do Sistema Nervoso Central/veterinária , Doenças do Cão/mortalidade , Sarcoma Histiocítico/veterinária , Meningioma/veterinária , Animais , California , Neoplasias do Sistema Nervoso Central/mortalidade , Doenças do Cão/sangue , Doenças do Cão/líquido cefalorraquidiano , Doenças do Cão/patologia , Cães , Feminino , Sarcoma Histiocítico/mortalidade , Masculino , Meningioma/mortalidade , Registros/veterinária , Estudos Retrospectivos , Análise de Sobrevida
13.
Artigo em Inglês | MEDLINE | ID: mdl-32863855

RESUMO

OBJECTIVE: Conventional selection of pre-ictal EEG epochs for seizure prediction algorithm training data typically assumes a continuous pre-ictal brain state preceding a seizure. This is carried out by defining a fixed duration, pre-ictal time period before seizures from which pre-ictal training data epochs are uniformly sampled. However, stochastic physiological and pathological fluctuations in EEG data characteristics and underlying brain states suggest that pre-ictal state dynamics may be more complex, and selection of pre-ictal training data segments to reflect this could improve algorithm performance. METHODS: We propose a semi-supervised technique to select pre-ictal training data most distinguishable from interictal EEG according to pre-specified data characteristics. The proposed method uses hierarchical clustering to identify optimal pre-ictal data epochs. RESULTS: In this paper we compare the performance of a seizure forecasting algorithm with and without hierarchical clustering of pre-ictal periods in chronic iEEG recordings from six canines with naturally occurring epilepsy. Hierarchical clustering of training data improved results for Time In Warning (TIW) (0.18 vs. 0.23) and False Positive Rate (FPR) (0.5 vs. 0.59) when evaluated across all subjects (p<0.001, n=6). Results were mixed when evaluating TIW, FPR, and Sensitivity for individual dogs. CONCLUSION: Hierarchical clustering is a helpful method for training data selection overall, but should be evaluated on a subject-wise basis. SIGNIFICANCE: The clustering method can be used to optimize results of forecasting towards sensitivity or TIW or FPR, and therefore can be useful for epilepsy management.

14.
J Vet Intern Med ; 34(1): 258-265, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31769119

RESUMO

BACKGROUND: Congenital myasthenic syndromes (CMSs) are a group of inherited disorders of neuromuscular transmission that may be presynaptic, synaptic, or postsynaptic. Causative mutations have been identified in 4 breeds including the Labrador Retriever, Jack Russell Terrier, Heideterrier, and Danish Pointing Dog. HYPOTHESIS/OBJECTIVE: Clinical and genetic characterization of a neuromuscular disorder in Golden Retriever (GR) puppies. ANIMALS: Four GR puppies from California were evaluated for generalized muscle weakness beginning at weaning. Biological specimens were collected from the affected puppies, and familial information was obtained. Blood or buccal swabs were obtained from 63 unaffected GRs. METHODS: Complete physical, neurological, electrodiagnostic, and histological evaluations and biochemical quantification of muscle acetylcholine receptors were performed. Polymerase chain reaction was used to amplify the 17 exons of COLQ, and sequences were obtained by Sanger sequencing. Variant frequency was assessed in unrelated GRs and a public database. RESULTS: Clinical, neurological, and electrodiagnostic evaluations confirmed a disorder of neuromuscular transmission in a GR family. Sequencing of all exons and splice sites of a primary candidate gene, COLQ, identified a point mutation that predicts an amino acid substitution (G294R). The primary COLQ transcript was absent from affected muscle samples. All affected puppies were homozygous for the mutation, which was not detected outside this GR family or in other breeds. CONCLUSIONS AND CLINICAL IMPORTANCE: We confirmed the diagnosis of a CMS in GR puppies and identified a novel COLQ mutation. The COLQ gene encodes the collagenous tail of acetylcholinesterase, the enzyme responsible for termination of skeletal muscle contraction by clearing acetylcholine at the neuromuscular junction. Clinicians and breeders should be aware of this CMS in GR puppies with an early onset of weakness.


Assuntos
Acetilcolinesterase/genética , Doenças do Cão/genética , Predisposição Genética para Doença , Síndromes Miastênicas Congênitas/veterinária , Animais , Doenças do Cão/diagnóstico , Cães , Feminino , Masculino , Síndromes Miastênicas Congênitas/diagnóstico , Síndromes Miastênicas Congênitas/genética , Receptores Colinérgicos
15.
J Vet Intern Med ; 33(2): 708-716, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30575120

RESUMO

BACKGROUND: Monitoring of intracranial pressure (ICP) is a critical component in the management of intracranial hypertension. Safety, efficacy, and optimal location of microsensor devices have not been defined in dogs. HYPOTHESIS/OBJECTIVE: Assessment of ICP using a microsensor transducer is feasible in anesthetized and conscious animals and is independent of transducer location. Intraparenchymal transducer placement is associated with more adverse effects. ANIMALS: Seven adult, bred-for-research dogs. METHODS: In a prospective investigational study, microsensor ICP transducers were inserted into subdural and intraparenchymal locations at defined rostral or caudal locations within the rostrotentorial compartment under general anesthesia. Mean arterial pressure and ICP were measured continuously during physiological maneuvers, and for 20 hours after anesthesia. RESULTS: Baseline mean ± SD values for ICP and cerebral perfusion pressure were 7.2 ± 2.3 and 78.9 ± 7.6 mm Hg, respectively. Catheter position did not have a significant effect on ICP measurements. There was significant variation from baseline ICP accompanying physiological maneuvers (P < .001) and with normal activities, especially with changes in head position (P < .001). Pathological sequelae were more evident after intraparenchymal versus subdural placement. CONCLUSIONS AND CLINICAL IMPORTANCE: Use of a microsensor ICP transducer was technically straightforward and provided ICP measurements within previously reported reference ranges. Results support the use of an accessible dorsal location and subdural positioning. Transient fluctuations in ICP are normal events in conscious dogs and large variations associated with head position should be accounted for when evaluating animals with intracranial hypertension.


Assuntos
Cães , Pressão Intracraniana/fisiologia , Monitorização Fisiológica/veterinária , Transdutores de Pressão/veterinária , Animais , Cateteres de Demora/veterinária , Circulação Cerebrovascular , Desenho de Equipamento/veterinária , Feminino , Cabeça , Miniaturização/instrumentação , Monitorização Fisiológica/efeitos adversos , Monitorização Fisiológica/instrumentação , Estudos Prospectivos , Reprodutibilidade dos Testes , Transdutores de Pressão/efeitos adversos
16.
ACS Nano ; 13(3): 2858-2869, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30714717

RESUMO

Nanoparticles' enhanced permeation and retention (EPR) variations due to tumor heterogeneity in naturally occurring brain tumors are commonly neglected in preclinical nanomedicine studies. Recent pathological studies have shown striking similarities between brain tumors in humans and dogs, indicating that canine brain tumors may be a valuable model to evaluate nanoparticles' EPR in this context. We recruited canine clinical cases with spontaneous brain tumors to investigate nanoparticles' EPR in different brain tumor pathologies using surface-enhanced Raman spectroscopy (SERS). We used gold nanoparticles due to their surface plasmon effect that enables their sensitive and microscopic resolution detection using the SERS technique. Raman microscopy of the resected tumors showed heterogeneous EPR of nanoparticles into oligodendrogliomas and meningiomas of different grades, without any detectable traces in necrotic parts of the tumors or normal brain. Raman observations were confirmed by scanning electron microscopy (SEM) and X-ray elemental analyses, which enabled localization of individual nanoparticles embedded in tumor tissues. Our results demonstrate nanoparticles' EPR and its variations in clinically relevant, spontaneous brain tumors. Such heterogeneities should be considered alongside routine preoperative imaging and histopathological analyses in order to accelerate clinical management of brain tumors using nanomedicine approaches.


Assuntos
Neoplasias Encefálicas/química , Neoplasias Encefálicas/diagnóstico por imagem , Nanomedicina , Nanopartículas/química , Animais , Análise Química do Sangue , Neoplasias Encefálicas/cirurgia , Cães , Ouro/química , Imageamento por Ressonância Magnética , Tamanho da Partícula , Dióxido de Silício/química , Propriedades de Superfície
17.
Neuromuscul Disord ; 18(12): 942-52, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18990577

RESUMO

Recent studies have identified a number of forms of muscular dystrophy, termed dystroglycanopathies, which are associated with loss of natively glycosylated alpha-dystroglycan. Here we identify a new animal model for this class of disorders in Sphynx and Devon Rex cats. Affected cats displayed a slowly progressive myopathy with clinical and histologic hallmarks of muscular dystrophy including skeletal muscle weakness with no involvement of peripheral nerves or CNS. Skeletal muscles had myopathic features and reduced expression of alpha-dystroglycan, while beta-dystroglycan, sarcoglycans, and dystrophin were expressed at normal levels. In the Sphynx cat, analysis of laminin and lectin binding capacity demonstrated no loss in overall glycosylation or ligand binding for the alpha-dystroglycan protein, only a loss of protein expression. A reduction in laminin-alpha2 expression in the basal lamina surrounding skeletal myofibers was also observed. Sequence analysis of translated regions of the feline dystroglycan gene (DAG1) in affected cats did not identify a causative mutation, and levels of DAG1 mRNA determined by real-time QRT-PCR did not differ significantly from normal controls. Reduction in the levels of glycosylated alpha-dystroglycan by immunoblot was also identified in an affected Devon Rex cat. These data suggest that muscular dystrophy in Sphynx and Devon Rex cats results from a deficiency in alpha-dystroglycan protein expression, and as such may represent a new type of dystroglycanopathy where expression, but not glycosylation, is affected.


Assuntos
Distroglicanas/deficiência , Músculo Esquelético/patologia , Distrofia Muscular Animal/patologia , Animais , Biópsia , Gatos , Modelos Animais de Doenças , Distroglicanas/genética , Distroglicanas/metabolismo , Feminino , Imunofluorescência , Glicosilação , Immunoblotting , Laminina/metabolismo , Lectinas/metabolismo , Masculino , Debilidade Muscular/metabolismo , Debilidade Muscular/patologia , Músculo Esquelético/metabolismo , Distrofia Muscular Animal/genética , Distrofia Muscular Animal/metabolismo , Reação em Cadeia da Polimerase
18.
J Am Vet Med Assoc ; 233(11): 1748-55, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19046034

RESUMO

OBJECTIVE: To evaluate the number and types of underlying disorders detected in dogs with aspiration pneumonia and determine the survival rate among affected dogs. DESIGN: Retrospective case series. Animals-88 dogs with aspiration pneumonia. PROCEDURES: Medical records were reviewed to identify disease processes that could result in aspiration pneumonia. To assess outcome (ie, survival to discharge from the hospital or nonsurvival), dogs were grouped by the type and number of underlying disease processes. Duration of hospitalization and radiographic severity of disease were evaluated with regard to case outcome. RESULTS: As the cause of aspiration pneumonia, a single underlying disorder was identified in 60 of the 88 dogs; 2 or more diseases were identified in the remaining dogs. Esophageal disease (n = 35), vomiting (34), neurologic disorders (24), laryngeal disease (16), and postanesthetic aspiration (12) were identified most commonly. Overall, 68 dogs survived to discharge from the hospital (survival rate, 77%). Survival rates were comparable among dogs regardless of the underlying cause of aspiration pneumonia. Radiographic severity of disease and duration of hospitalization did not influence survival. CONCLUSIONS AND CLINICAL RELEVANCE: Among these study dogs, aspiration pneumonia was associated with a high survival rate. The presence of more than 1 underlying disease associated with aspiration pneumonia did not adversely impact survival rate. Interestingly, radiographic severity of disease and duration of hospitalization were not associated with overall survival rate.


Assuntos
Antibacterianos/uso terapêutico , Doenças do Cão/etiologia , Doenças do Cão/mortalidade , Pulmão/patologia , Pneumonia Aspirativa/veterinária , Anestesia/efeitos adversos , Anestesia/veterinária , Animais , Doenças do Cão/tratamento farmacológico , Doenças do Cão/patologia , Cães , Doenças do Esôfago/complicações , Doenças do Esôfago/veterinária , Feminino , Doenças da Laringe/complicações , Doenças da Laringe/veterinária , Tempo de Internação , Masculino , Doenças do Sistema Nervoso/complicações , Doenças do Sistema Nervoso/veterinária , Pneumonia Aspirativa/etiologia , Pneumonia Aspirativa/mortalidade , Pneumonia Aspirativa/patologia , Radiografia Torácica/métodos , Radiografia Torácica/veterinária , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Taxa de Sobrevida , Resultado do Tratamento , Vômito/complicações , Vômito/veterinária
19.
IEEE J Transl Eng Health Med ; 6: 2500112, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30310759

RESUMO

Brain stimulation has emerged as an effective treatment for a wide range of neurological and psychiatric diseases. Parkinson's disease, epilepsy, and essential tremor have FDA indications for electrical brain stimulation using intracranially implanted electrodes. Interfacing implantable brain devices with local and cloud computing resources have the potential to improve electrical stimulation efficacy, disease tracking, and management. Epilepsy, in particular, is a neurological disease that might benefit from the integration of brain implants with off-the-body computing for tracking disease and therapy. Recent clinical trials have demonstrated seizure forecasting, seizure detection, and therapeutic electrical stimulation in patients with drug-resistant focal epilepsy. In this paper, we describe a next-generation epilepsy management system that integrates local handheld and cloud-computing resources wirelessly coupled to an implanted device with embedded payloads (sensors, intracranial EEG telemetry, electrical stimulation, classifiers, and control policy implementation). The handheld device and cloud computing resources can provide a seamless interface between patients and physicians, and realtime intracranial EEG can be used to classify brain state (wake/sleep, preseizure, and seizure), implement control policies for electrical stimulation, and track patient health. This system creates a flexible platform in which low demand analytics requiring fast response times are embedded in the implanted device and more complex algorithms are implemented in offthebody local and distributed cloud computing environments. The system enables tracking and management of epileptic neural networks operating over time scales ranging from milliseconds to months.

20.
J Am Vet Med Assoc ; 230(1): 76-83, 2007 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-17199496

RESUMO

OBJECTIVE: To assess the clinical course of disease and risk factors associated with outcome in dogs with tetanus. DESIGN: Retrospective case series. ANIMALS: 38 dogs with tetanus. PROCEDURES: Data were collected from medical records of dogs with tetanus, including signalment; wound characteristics; initial clinical signs; severity of worst clinical signs; time to wound management, antimicrobial treatment, and antitoxin administration; and 28-day survival rate. Statistical analyses were performed to evaluate relationships between the potentially predictive variables and disease progression and outcome. RESULTS: The 28-day survival rate was 77% (among 35 uncensored dogs). The most common initial clinical signs in affected dogs were ocular (n = 18) and facial (11) abnormalities. Nineteen dogs progressed to recumbency with severe muscle spasms, and 14 dogs had high or low heart rate or blood pressure values. Eight dogs died or were euthanized because of complications of tetanus. There was a significant association between younger age and development of more severe clinical signs. Furthermore, a significant inverse relationship between development of severe clinical signs and survival was identified. There was no association between earlier initiation of wound management, antimicrobial administration, or antitoxin administration and either progression of signs or 28-day survival rate. Wound type was not associated with 28-day survival rate. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that younger dogs with tetanus may be more likely to develop severe clinical signs. The prognosis for survival in dogs with tetanus is good if abnormalities in heart rate or blood pressure values do not develop.


Assuntos
Doenças do Cão/mortalidade , Doenças do Cão/patologia , Antitoxina Tetânica/uso terapêutico , Tétano/veterinária , Fatores Etários , Animais , Pressão Sanguínea/fisiologia , Doenças do Cão/tratamento farmacológico , Cães , Feminino , Frequência Cardíaca/fisiologia , Masculino , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Taxa de Sobrevida , Tétano/tratamento farmacológico , Tétano/mortalidade , Tétano/patologia , Fatores de Tempo , Resultado do Tratamento , Cicatrização/fisiologia
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