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D O'Grady

Publications and source records attributed to D O'Grady.

15 recordsLinked to original sources
PubMed2006

Genotyping of Mycobacterium bovis isolates from badgers in four areas of the Republic of Ireland by restriction fragment length polymorphism analysis.

An analysis of the molecular epidemiology of Mycobacterium bovis in badgers was made in four selected areas of the Republic of Ireland in which an intensive badger removal programme was being carried out over a period of five years. Tissue samples from 2310 badgers were cultured. Restriction fragment length polymorphism (RFLP) analysis with IS6110, polymorphic GC-rich sequence (PGRS) and direct repeat sequence (DR) probes was applied to the isolates from 398 badgers, and 52 different rflp types were identified. Most of the isolates belonged to seven predominant types, and the other 45 types were represented by few isolates. An analysis suggests that some of these 45 types may have been introduced by the inward migration of badgers and others may have been the result of genetic changes to one of the prevalent types. The badgers were divided into groups on the basis of the sett at which they were captured, and RFLP typing was applied to isolates from two or more badgers from 85 groups. Multiple RFLP types were identified among isolates from 50 of these groups, suggesting that badgers probably moved frequently between group territories.

Animals↗
PubMed2001

Virulence-associated protein characterisation of Rhodococcus equi isolated from bovine lymph nodes.

Rhodococcus equi has a low pathogenicity in cattle, but it occasionally causes lymph node granulomas, which are detected at abattoir post mortem inspection, and must be distinguished from tuberculous granulomas. Lymph node lesions were detected in 6719 cattle, from a total of 3,263,622 cattle examined post mortem in abattoirs, in the Republic of Ireland, during 1997 and 1998. Histological examination was performed on all lesions, principally for the purpose of identifying animals with tuberculosis. A total of 1122 of the lesions were cultured on blood agar and on Stonebrinks and Lowenstein-Jensen medium containing pyruvate, because the histological findings were difficult to interpret or were suggestive of R. equi infection. R. equi was isolated from 264 lesions. Almost all of the R. equi granulomas were confined to a single lymph node, and were present predominantly in the retropharyngeal, bronchial and mediastinal lymph nodes. R. equi granulomas were present in a significantly higher proportion of the lesions detected in steers and heifers compared to cows. The prevalence in the total population of 3.3 million cattle examined post mortem was 0.008%. The 15-17kDa antigens, associated with virulence in this organism, and the 20kDa antigen, associated with intermediate virulence, were not detected in isolates from 146 cattle, analysed by immunoblot assays. A PCR assay to detect the plasmid gene encoding the 15-17kDa antigens was also negative for isolates from these 146 animals. Plasmids were not detected in 30 isolates which were examined.

Actinomycetales Infections↗
PubMed2000

Identification of a novel DNA probe for strain typing Mycobacterium bovis by restriction fragment length polymorphism analysis.

Bovine tuberculosis caused by Mycobacterium bovis remains a significant disease of farmed cattle in many countries despite ongoing tuberculosis eradication programs. Molecular typing methods such as restriction fragment length polymorphism (RFLP) analysis and spoligotyping have been used to identify related herd breakdowns in an attempt to identify more precisely the route of infection into cattle herds and to trace the transmission of bovine tuberculosis. A recent geographical survey of Irish M. bovis isolates demonstrated that a significant proportion of isolates ( approximately 20%) exhibit a common strain type, limiting the value of current strain typing methods as an epidemiological tool. We have identified and cloned a region of the M. bovis genome, pUCD, which generates a clear, highly polymorphic banding pattern when used as an RFLP probe on AluI restriction-digested M. bovis genomic DNA and which effectively subdivides this common strain type. When used to type 60 Irish M. bovis isolates, pUCD exhibited greater discriminatory power than the commonly used mycobacterial RFLP probes IS6110, PGRS, and DR and detected an equivalent number of strain types to a combination of these three probes. pUCD also detected significantly more strain types than the spoligotyping technique, while maintaining a high level of concordance between epidemiologically related and unrelated herd breakdowns. The polymorphic element within pUCD remains to be fully characterized, however the potential for this probe to greatly decrease the workload necessary to genotype M. bovis by RFLP analysis is compelling.

Animals↗
PubMed2000

Characterization of the Mycobacterium bovis restriction fragment length polymorphism DNA probe pUCD and performance comparison with standard methods.

In this study, the newly described Mycobacterium bovis restriction fragment length polymorphism (RFLP) typing probe pUCD was characterized by sequence analysis and the previously observed polymorphic banding pattern was reproduced with a combination of three oligonucleotide probes in a single, mixed hybridization. In addition, the ability of pUCD to distinguish between 299 M. bovis isolates from the Republic of Ireland was assessed in relation to established methods and a statistical function for objective comparison of RFLP probes was derived. It was found that typing with pUCD alone produced greater discrimination between M. bovis isolates than typing with the commonly used mycobacterial DNA probes IS6110, PGRS, and DR and also by the spoligotyping technique. pUCD and DR in combination produced the highest level of discrimination while maintaining a high level of concordance with known epidemiological data relating to the samples. The reduction of pUCD to the level of oligonucleotides should in future allow pUCD and DR to be included together in a mixed hybridization, thus producing a high level of M. bovis strain type discrimination from a single round of RFLP analysis.

Animals↗
PubMed2000

Restriction fragment length polymorphism analysis of Mycobacterium avium isolates from animal and human sources.

Restriction fragment length polymorphism (RFLP) analysis using probes derived from the insertion sequences IS901, IS1245 and IS1311, was carried out on Mycobacterium avium isolates obtained from 18 human patients, 44 deer, 14 pigs and five cattle in the Republic of Ireland. Forty-two of the cervine isolates and two of the bovine isolates contained IS901, while this insertion sequence was absent from all of the human and porcine isolates. RFLP analysis with IS901 probe differentiated the 44 field isolates which contained this element into three types. All of the IS901-positive isolates had a characteristic three-band IS1245 hybridisation pattern and a characteristic single-band IS1311 hybridisation pattern. The IS901-negative isolates exhibited highly polymorphic IS1245 and IS1311 hybridisation patterns which differentiated the human and porcine isolates into a wide diversity of strain types.

Animals↗
PubMed1999

Study of restriction fragment length polymorphism analysis and spoligotyping for epidemiological investigation of Mycobacterium bovis infection.

Restriction fragment length polymorphism (RFLP) analysis with probes derived from the insertion element IS6110, the direct repeat sequence, and the polymorphic GC-rich sequence (PGRS) and a PCR-based typing method called spacer oligonucleotide typing (spoligotyping) were used to strain type Mycobacterium bovis isolates from the Republic of Ireland. Results were assessed for 452 isolates which were obtained from 233 cattle, 173 badgers, 33 deer, 7 pigs, 5 sheep, and 1 goat. Eighty-five strains were identified by RFLP analysis, and 20 strains were identified by spoligotyping. Twenty percent of the isolates were the most prevalent RFLP type, while 52% of the isolates were the most prevalent spoligotype. Both the prevalent RFLP type and the prevalent spoligotype were identified in isolates from all animal species tested and had a wide geographic distribution. Isolates of some RFLP types and some spoligotypes were clustered in regions consisting of groups of adjoining counties. The PGRS probe gave better differentiation of strains than the IS6110 or DR probes. The majority of isolates from all species carried a single IS6110 copy. In four RFLP types IS6110 polymorphism was associated with deletion of fragments equivalent in size to one or two direct variable repeat sequences. The same range and geographic distribution of strains were found for the majority of isolates from cattle, badgers, and deer. This suggests that transmission of infection between these species is a factor in the epidemiology of M. bovis infection in Ireland.

Animals↗
PubMed1989

Adult infectious diseases: management in a general hospital.

Conflicting views exist as to where patients with infectious diseases (IDs) are best managed. In an effort to define the role of an IDs Unit in this country, we undertook a four-year survey of IDs cases referred to our isolation facility which is part of the Gastroenterology department. Ninety-three per cent of 250 cases referred had either diarrhoea (48%) or jaundice (45%). Two thirds of the total had an infective, and one third a non-infective basis for their illness. Since diarrhoea and jaundice dominated the clinical presentations of these cases, having the IDs facility within the Gastroenterology department made for speedy diagnosis and management of both infectious and non-infectious cases. Where referral and/or transfer to other units was necessary, it still proved helpful to locate the IDs facility within a regional multidisciplinary hospital, particularly in view of the wide range of medical and surgical conditions referred as putative IDs.

Adolescent↗
PubMed1976

Treatment of children with phenylketonuria using a phenylalanine-free protein hydrolysate (Albumaid XP).

Albumaid XP, a phenylalanine-free protein hydrolysate, was used for treatment of five phenylketonuric infants born between January, 1970, and September, 1972. The results were compared with those obtained from the five infants most recently treated with Lofenalac in our clinic prior to 1970. Treatment was begun by 2 months of age in all instances. Satisfactory physical growth and mental development were achieved using either Albumaid XP or Lofenalac, and there were no major differences in the outcomes with either treatment. The two protein sources may be used interchangeably for treatment of phenylketonuria.

Amino Acids↗