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71.
Distribution of alpha‐neoendorphin,ACTH (18–39) and beta‐endorphin (1–27) in the alpaca brainstem
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Manuel L. Sánchez Eliana de Souza Luis A. Aguilar Rafael Coveñas 《Anatomia, histologia, embryologia》2018,47(5):481-492
Using an immunocytochemical technique, we have studied in the alpaca brainstem the distribution of immunoreactive structures containing prodynorphin (alpha‐neoendorphin)‐ and pro‐opiomelanocortin (adrenocorticotrophin hormone (18–39) (ACTH), beta‐endorphin (1–27))‐derived peptides. No peptidergic‐immunoreactive cell body was observed. Immunoreactive fibres were widely distributed, although in most of the brainstem nuclei the density of the peptidergic fibres was low or very low. In general, the distribution of the immunoreactive fibres containing the peptides studied was very similar. A close anatomical relationship occurred among the fibres containing alpha‐neoendorphin, ACTH or beta‐endorphin (1–27), suggesting a functional interaction among the three peptides in many of the brainstem nuclei. The number of fibres belonging to the prodynorphin system was higher than that of the pro‐opiomelanocortin system. A moderate/low density of immunoreactive fibres was observed in 65.11% (for alpha‐neoendorphin (1–27)), 18.18% (for ACTH) and 13.95% (for beta‐endorphin) of the brainstem nuclei/tracts. In the alpaca brainstem, a high density of immunoreactive fibres was not observed. The neuroanatomical distribution of the immunoreactive fibres suggests that the peptides studied are involved in auditory, motor, gastric, feeding, vigilance, stress, respiratory and cardiovascular mechanisms, taste response, sleep‐waking cycle and the control of pain transmission. 相似文献
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Osteochondrosis (OC) is an injury to cartilage canals with a following necrosis in the growth cartilage, from there it can develop to osteochondrosis dissecans (OCD). Due to its high impact in the equine industry, new insights into predisposing factors and potential high‐risk genetic variants are warranted. This article reviews advancements in quantitative and molecular genetics in refining estimation of genetic parameters and identifying predisposing genetic loci. Heritabilities were highest for hock OC with estimates at 0.29–0.46 in Hanoverian warmblood and Norwegian trotters, whereas in Thoroughbreds only very low genetic variation seemed to be present in hock OC lesions. Whole genome scans using the Illumina Equine SNP50 or SNP70 Beadchip were performed in Thoroughbred, Standardbred, French and Norwegian trotter, Hanoverian and Dutch warmblood. Validation studies in Spanish Purebred and Hanoverian warmblood horses corroborated OC risk loci on ECA 3, 14, 27 and 29. Particularly, a strong association with hock‐OCD was found for a single nucleotide polymorphism (SNP) on horse chromosome (ECA) 3 upstream to the LCORL gene. Gene expression and microRNA analyses may be helpful to understand pathophysiological processes in equine OC and to connect OCD‐associated genomic regions with potential candidate genes. Furthermore progress in elucidating the underlying genetic variants and pathophysiological changes in OC may be expected from whole genome DNA and RNA next‐generation sequencing studies. 相似文献
76.
Canine GM2‐Gangliosidosis Sandhoff Disease Associated with a 3‐Base Pair Deletion in the HEXB Gene
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P. Wang P.S. Henthorn E. Galban G. Lin T. Takedai M. Casal 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):340-347
Background
GM2‐gangliosidosis is a fatal neurodegenerative lysosomal storage disease (LSD) caused by deficiency of either β‐hexosaminidase A (Hex‐A) and β‐hexosaminidase B (Hex‐B) together, or the GM2 activator protein. Clinical signs can be variable and are not pathognomonic for the specific, causal deficiency.Objectives
To characterize the phenotype and genotype of GM2‐gangliosidosis disease in an affected dog.Animals
One affected Shiba Inu and a clinically healthy dog.Methods
Clinical and neurologic evaluation, brain magnetic resonance imaging (MRI), assays of lysosomal enzyme activities, and sequencing of all coding regions of HEXA, HEXB, and GM2A genes.Results
A 14‐month‐old, female Shiba Inu presented with clinical signs resembling GM2‐gangliosidosis in humans and GM1‐gangliosidosis in the Shiba Inu. Magnetic resonance imaging (MRI) of the dog's brain indicated neurodegenerative disease, and evaluation of cerebrospinal fluid (CSF) identified storage granules in leukocytes. Lysosomal enzyme assays of plasma and leukocytes showed deficiencies of Hex‐A and Hex‐B activities in both tissues. Genetic analysis identified a homozygous, 3‐base pair deletion in the HEXB gene (c.618‐620delCCT).Conclusions and Clinical Importance
Clinical, biochemical, and molecular features are characterized in a Shiba Inu with GM2‐gangliosidosis. The deletion of 3 adjacent base pairs in HEXB predicts the loss of a leucine residue at amino acid position 207 (p.Leu207del) supporting the hypothesis that GM2‐gangliosidosis seen in this dog is the Sandhoff type. Because GM1‐gangliosidosis also exists in this breed with almost identical clinical signs, genetic testing for both GM1‐ and GM2‐gangliosidosis should be considered to make a definitive diagnosis. 相似文献77.
78.
Contrast‐Enhanced Ultrasound Examination for the Assessment of Renal Perfusion in Cats with Chronic Kidney Disease
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E. Stock D. Paepe S. Daminet E. Vandermeulen L. Duchateau K. Vanderperren 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):260-266
Background
Contrast‐enhanced ultrasound examination (CEUS) is a functional imaging technique allowing noninvasive assessment of tissue perfusion. Studies in humans show that the technique holds great potential to be used in the diagnosis of chronic kidney disease (CKD). However, data in veterinary medicine are currently lacking.Objectives
To evaluate renal perfusion using CEUS in cats with CKD.Animals
Fourteen client‐owned cats with CKD and 43 healthy control cats.Methods
Prospective case‐controlled clinical trial using CEUS to evaluate renal perfusion in cats with CKD compared to healthy control cats. Time‐intensity curves were created, and perfusion parameters were calculated using off‐line software. A linear mixed model was used to examine differences between perfusion parameters of cats with CKD and healthy cats.Results
In cats with CKD, longer time to peak and shorter mean transit times were observed for the renal cortex. In contrast, a shorter time to peak and rise time were seen for the renal medulla. The findings for the renal cortex indicate decreased blood velocity and shorter total duration of enhancement, likely caused by increased vascular resistance in CKD. Increased blood velocity in the renal medulla has not been described before and may be because of a different response to regulatory factors in cortex and medulla.Conclusions and Clinical Importance
Contrast‐enhanced ultrasound examination was capable of detecting perfusion changes in cats with CKD. Further research is warranted to assess the diagnostic capabilities of CEUS in early stage of the disease process. 相似文献79.
Comparison of Single,Averaged, and Pooled Urine Protein:Creatinine Ratios in Proteinuric Dogs Undergoing Medical Treatment
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S. Shropshire J. Quimby R. Cerda 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):288-294
Background
Monitoring urine protein:creatinine ratios (UPC ) in dogs with protein‐losing nephropathy (PLN ) is challenging because of day‐to‐day variation in UPC results.Hypothesis/Objectives
Determine whether single, averaged, or pooled samples from PLN dogs receiving medical treatment yield comparable UPC s, regardless of degree of proteinuria.Animals
Twenty‐five client‐owned PLN dogs receiving medical treatment.Methods
UPC ratios were prospectively measured in each dog utilizing 3 methods: single in‐hospital sample (day 3), average sample (days 1–3), and pooled sample (equal pooling of urine from days 1–3). Bland‐Altman analysis was performed to evaluate agreement between methods for all dogs, as well as in subgroups of dogs (UPC ≤4 or UPC >4).Results
For all dogs, Bland‐Altman log‐transformed 95% limits of agreement were ?0.07–0.18 (single versus pooled UPC ), ?0.06–0.16 (single versus average UPC ), and ?0.06–0.04 (pooled versus average UPC ). For dogs with UPC ≤4, Bland‐Altman 95% limits of agreement were ?0.42–0.82 (single versus pooled UPC ), ?0.38–0.76 (single versus average UPC ), and ?0.27–0.25 (pooled versus average UPC ). For dogs with UPC >4, Bland‐Altman 95% limits of agreement were ?0.17–2.4 (single versus pooled UPC ), ?0.40–2.2 (single versus average UPC ), and ?0.85–0.43 (pooled versus average UPC ).Conclusions and Clinical Importance
UPC ratios from all methods were comparable in PLN dogs receiving medical treatment. In PLN dogs with UPC >4, more variability between methods exists likely because of higher in‐hospital results, but whether this finding is clinically relevant is unknown.80.