Hanne Jahns
University College Dublin
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Featured researches published by Hanne Jahns.
Veterinary Pathology | 2006
Hanne Jahns; John J. Callanan; Máire C. McElroy; D. J. Sammin; Hugh F. Bassett
Brains from 100 horses, aged 2-25 years, were systematically examined by histopathology at 46 different neuroanatomical sites. The horses were sourced from a slaughterhouse (group A, n = 57), from a kennel that collected dead animals, and from 2 diagnostic laboratories (group B, n = 43). All horses from group A and 26 horses from group B were examined by a veterinarian in the period before death. None of the horses were known to exhibit clinical signs suggestive of neurologic disease. Among the main changes identified were vacuolation in the neuropil (n = 73), neurons (n = 32), white matter (n = 31), and focal perivascular lymphoid cell infiltrates (n = 35). Spheroids were frequently seen (n = 91), and 10 horses each had more than 10 spheroids in the cuneate or gracile nucleus. Statistically significant age-related changes noted included intraneuronal (n = 97) and glial or extracellular lipofuscin deposition (n = 41), hemosiderin deposition around blood vessels (n = 60), and calcium depositions (n = 24). One horse had low-grade nonsuppurative meningoencephalitis; Alzheimer type II cells were detected in the brains of 2 horses. Hyalinized vessel walls in the cerebellum were observed in 1 horse. It was concluded that some histopathologic changes are a frequent feature in equine brains, which has implications for the pathologists involved in equine neurology and disease surveillance.
Journal of Tissue Engineering and Regenerative Medicine | 2015
Florent David; Tanya J. Levingstone; Wilfried Schneeweiss; Marie de Swarte; Hanne Jahns; John P. Gleeson; Fergal J. O'Brien
An unmet need remains for a bone graft substitute material that is biocompatible, biodegradable and capable of promoting osteogenesis safely in vivo. The aim of this study was to investigate the use of a novel collagen–hydroxyapatite (CHA) bone graft substitute in the clinical treatment of a mandibular bone cyst in a young horse and to assess its potential to enhance repair of the affected bone. A 2 year‐old thoroughbred filly, presenting with a multilobulated aneurysmal bone cyst, was treated using the CHA scaffold. Post‐operative clinical follow‐up was carried out at 2 weeks and 3, 6 and 14 months. Cortical thickening in the affected area was observed from computed tomography (CT) examination as early as 3 months post‐surgery. At 14 months, reduced enlargement of the operated mandible was observed, with no fluid‐filled area. The expansile cavity was occupied by moderately dense mineralized tissue and fat and the compact bone was remodelled, with a clearer definition between cortex and medulla observed. This report demonstrates the promotion of enhanced bone repair following application of the CHA scaffold material in this craniomaxillofacial indication, and thus the potential of this material for translation to human applications. Copyright
Journal of Veterinary Diagnostic Investigation | 2010
Hanne Jahns; Paul Daly; Máire C. McElroy; D. J. Sammin; Hugh F. Bassett; John J. Callanan
A neuropathologic survey was conducted on mink brains from the 5 licensed mink farms in Ireland. The survey was part of a transmissible spongiform encephalopathy surveillance study. Aleutian disease (AD) was present on 4 of the 5 farms (80%). Neuropathologic features of nonsuppurative meningoencephalitis were common in mink from the 4 affected farms but were absent in the mink from the fifth farm, which was free of AD. The meningoencephalitis was characterized by infiltrates of lymphocytes and plasma cells, which were present in meninges, perivascular spaces, and the brain parenchyma. Fibrinoid necrotizing arteritis was seen in 11 mink brains, all of which were obtained from a single farm. Aleutian mink disease virus (AMDV) sequences for the capsid protein VP2 were obtained from brain samples from all affected farms. Although containing previously unreported amino acid residues, similarities with European and North American isolates were observed in the hypervariable regions within VP2, suggesting Irish AMDV is related to those isolates. The predicted amino acid residues, suspected of conferring pathogenicity at certain positions of the VP2 sequence, were present in the viral nucleic acid sequences.
Veterinary Record | 2006
Hanne Jahns; John J. Callanan; D. J. Sammin; Máire C. McElroy; Hugh F. Bassett
Samples of brain and lymphoid tissues from 1107 meat and bone meal-fed, culled adult pigs from 24 Irish farms were examined for evidence of transmissible spongiform encephalopathy (tse) by histopathological, immunohistochemical and Western blotting techniques. No evidence of deposits of abnormal prion protein suggesting the presence of tse was found. Neuropil vacuolation was apparent in the rostral colliculus in 64 per cent of the brains examined and neuronal vacuolation was present in the dorsal vagal nucleus in 15·4 per cent of the brains. However, similar lesions have been described in pigs used as controls in a bovine spongiform encephalopathy challenge experiment. Age-related changes were also observed, including spheroids in the funicular nucleus of 24·5 per cent of the pigs, deposits of lipofuscin in the trigeminal neurons of 13·75 per cent, and mineral deposits in the walls of vessels in the dorsal vagal nucleus of 0·6 per cent. Low-grade non-suppurative inflammatory changes of uncertain origin were observed in 4 per cent of the animals.
Biology of Reproduction | 2016
Fernando Narciandi; B. Fernandez-Fuertes; Ilaina Khairulzaman; Hanne Jahns; Deirdre King; Emma K. Finlay; Ken H. Mok; S. Fair; P. Lonergan; Cliona O’Farrelly; Kieran G. Meade
ABSTRACT Beta-defensins are innate immune molecules, often described as antimicrobial peptides because of their bactericidal activity and are now known to have diverse additional functions, including cell signaling, chemoattraction, immunoregulation, and reproduction. In humans and primates, beta-defensin 126 has been shown to regulate the ability of sperm to swim through cervical mucus and to protect sperm from attack by the female immune system during transit toward the oviduct. Bovine beta-defensin 126 (BBD126) is the ortholog of human defensin 126, and computational analysis here revealed significant conservation between BBD126 and other mammalian orthologs at the N-terminus, although extensive sequence differences were detected at the C-terminus, implying possible species-specific roles for this beta-defensin in reproduction. We had previously demonstrated preferential expression of this and related beta-defensin genes in the bovine male reproductive tract, but no studies of bovine beta-defensin proteins have been performed to date. Here, we analyzed BBD126 protein using a monoclonal antibody (a-BBD126) generated against a 14 amino acid peptide sequence from the secreted fragment of BBD126. The specificity of a-BBD126 was validated by testing against the native form of the peptide recovered from bovine caudal epididymal fluid and recombinant BBD126 generated using a prokaryotic expression system. Western blot analysis of the native and recombinant forms showed that BBD126 exists as a dimer that was highly resistant to standard methods of dissociation. Immunohistochemical staining using a-BBD126 demonstrated BBD126 protein expression by epithelial cells of the caudal epididymis and vas deferens from both mature and immature bulls. BBD126 could also be seen (by confocal microscopy) to coat caudal sperm, with staining concentrated on the tail of the sperm cells. This study is the first to demonstrate beta-defensin 126 protein expression in the bovine reproductive tract and on bull sperm. Its dissociation-resistant dimeric structure is likely to have important functional implications for the role of BBD126 in bovine reproduction.
Veterinary Pathology | 2015
P. A. Kelly; D. Toolan; Hanne Jahns
Intestinal adenocarcinomas were identified in 76 adult deer from a closed herd of 193 breeding animals grazing pasture heavily infested with bracken fern (Pteridium aquilinum). Tumors were observed postmortem in 32 animals with rapid weight loss, and similar neoplasms were detected in a further 44 clinically normal deer at “cull.” Tumors were located in distal ileum, cecum, and proximal colon and presented as single (26%) or multiple (74%), variably sized, pale-gray, firm, poorly circumscribed neoplasms with associated intestinal strictures. Histopathologically tumors were well-differentiated, locally infiltrative, low-grade adenocarcinomas of tubular (51%), mucinous (33.5%), or mixed (15.5%) types. Extraintestinal metastases were not observed. The high incidence of intestinal adenocarcinoma within this herd suggests a specific and novel syndrome, and genetic and/or environmental factors may be involved in the pathogenesis.
Veterinary Microbiology | 2013
James Gibbons; Bryan Markey; Hanne Jahns; Fiona Boland; Y. Abbott; A. Burns; John Egan; Séamus Fanning; Montserrat Gutierrez; F. C. Leonard
MRSA CC5 spa type t002 appears to have a broad host range, has been isolated from animals and in-contact humans in Ireland and could potentially become established in pigs in Ireland. The aims of this study were to determine if MRSA CC5 spa type t002 could persist in the tissues of the porcine upper respiratory tract following intra-nasal inoculation; to determine the relative importance of environmental and animal sources of the bacterium in the transmission cycle and to determine the importance of the pharynx as a carriage site of Staphylococcus aureus and MRSA. Twelve pigs were inoculated intra-nasally with MRSA CC5 t002. After 1 or 6 days, the inoculated pigs were removed from the contaminated environment, were washed in an antiseptic solution and placed in a clean house with a group of naive pigs (in-contact group). Another group of naive pigs was placed in the contaminated environment to assess transmission from the environment (environmental group). Nasal swabs, environmental swabs and tissue samples from the upper respiratory tract were taken for MRSA culture. Infection rates were calculated for each group of exposed pigs. MRSA persisted in the pharyngeal tissues of 6 inoculated pigs for at least 30 days and higher counts of S. aureus were found in pharyngeal tissues than in other sites. In this study we were able to demonstrate the establishment of colonisation by MRSA CC5 spa type t002 in commercially sourced pigs already colonised by S. aureus; however, colonisation was sporadic despite the inoculation of large doses. Onward transmission via pig-to-pig contact or environmental contamination was possible and a significant difference was found between the proportion of pigs infected in the environmental group and the proportion infected in the in-contact group during the first 5 days. However, no significant difference was detected in overall infection rates between the 2 groups. The tissues of the pharynx were found to carry greater numbers of S. aureus than other tissues of the upper respiratory tract; therefore, pharyngeal carriage of MRSA and S. aureus in pigs may be more significant than previously thought.
Veterinary Record | 2016
Mara Rocchi; Madeleine Maley; Mark P. Dagleish; Catherine Vick; Dennis Ryan; Alison M. Lee; Hanne Jahns
WE would like to inform colleagues that we have reached a positive diagnosis (confirmed by sequencing) of rabbit haemorrhagic disease virus variant strain 2 (RHDV-2) infection in a wild rabbit from the Isle of Man and in three pet rabbits from the Republic of Ireland. The pet rabbits had been vaccinated against the classical RHDV-1 within three months of …
Veterinary Surgery | 2015
Wilfried Schneeweiss; Lea Krump; Lucy Metcalfe; Eoin Ryan; Marijke Eileen Beltman; Hanne Jahns; Florent David
OBJECTIVE To report successful minimally invasive treatment of a uterine leiomyoma in a cow and a mare. STUDY DESIGN Clinical report. ANIMAL POPULATION Limousine cow (n = 1), Thoroughbred mare (n = 1). METHODS A 10-year-old cow and an 18-year-old mare were presented for difficulties in breeding and infertility, respectively. Examination of the reproductive tract revealed the presence of a large mass attached to the uterine wall via a wide and short peduncle in both cases. The mass expanded into the uterine lumen in the mare and into the abdomen in the cow. Both masses were removed using a minimally invasive endoscopic approach and a vessel-sealing and dividing device. RESULTS Minimally invasive surgical resection of a subserosal and a submucosal leiomyoma with maximal sparing of uterine tissue resulted in a short convalescence period and apparent return to breeding function in a cow and a mare. Use of a vessel-sealing and dividing device provided excellent hemostasis and decreased tissue handling. CONCLUSION Leiomyoma with short, wide, and thick peduncles were treated successfully in a cow and a mare with minimally invasive endoscopic approaches aiming at maximal uterine tissue preservation.
Avian Diseases | 2013
Pamela Kelly; Hanne Jahns; Eugene Power; John Bainbridge; Kevin Kenny; Juan M. Corpa; Joseph P. Cassidy; John J. Callanan
SUMMARY Avian tuberculosis rarely affects ratites compared to other bird species and is typically caused by Mycobacterium avium species. This study describes the pathological and microbiological findings in three adult ostriches with mycobacteriosis, in one of which Mycobacterium bovis was isolated from the lesions. Post mortem examinations on ostriches from two different zoological collections in Ireland revealed multifocal caseous granulomas affecting the spleen and liver in all cases, with additional involvement of intestines in two cases. In one case, granulomas were present within the pharynx, at the thoracic inlet and multifocally on the pleural surface. Acid-fast bacilli were observed in all lesions. Mycobacterium sp. of the M. avium complex was isolated from the intestinal lesions in the two cases with intestinal involvement, and M. bovis sp. oligotype SB0140 was cultured from the liver of the third ostrich. This represents the first reported case of M. bovis infection in an ostrich. Avian tuberculosis due to M. bovis is rare and to date has been reported in only parrots and experimentally inoculated birds. Mycobacterium bovis needs to be considered as a possible cause of tuberculosis in ostriches because the lesions are similar to those observed with M. avium complex infection. RESUMEN Reporte de Caso—Micobacteriosis en avestruces (Struthio camelus), por la infección por Mycobacterium bovis y por el complejo Mycobacterium avium. La tuberculosis aviar rara vez afecta ratites en comparación con otras especies aviares y por lo general es causada por Mycobacterium avium sp. Este estudio describe los hallazgos patológicos y microbiológicos en tres avestruces adultas con micobacteriosis, en una de las cuales se aisló Mycobacterium bovis de las lesiones. Los exámenes de necropsia de avestruces de dos colecciones zoológicas diferentes en Irlanda reveló granulomas caseosos multifocales que afectaban el bazo y el hígado en todos los casos, con la participación adicional de los intestinos en dos casos. En un caso, los granulomas estaban presentes dentro de la faringe, en la entrada torácica y de manera multifocal en la superficie pleural. Se observaron bacilos ácido alcohol resistentes en todas las lesiones. Mycobacterium sp. del complejo M. avium fue aislado de las lesiones intestinales en los dos casos con afectación intestinal, y se cultivó M. bovis sp. oligotipo SB0140 a partir del hígado de la tercera avestruz. Esto representa el primer caso de infección por M. bovis en avestruces. Tuberculosis aviar por M. bovis es rara y hasta la fecha ha sido reportada sólo en loros y aves inoculadas experimentalmente. Mycobacterium bovis debe ser considerada como una posible causa de tuberculosis en avestruces porque las lesiones son similares a los observadas con el complejo M. avium.