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S O'Flaherty

Publications and source records attributed to S O'Flaherty.

12 recordsLinked to original sources
PubMed2005

Inhibition of bacteriophage K proliferation on Staphylococcus aureus in raw bovine milk.

AIMS: To assess the ability of staphylococcal bacteriophage K to inhibit Staphylococcus aureus in raw milk. METHODS AND RESULTS: The ability of bacteriophage (phage) to replicate in milk is important in situations where phage might be used as a therapeutic for bovine mastitis. Phage K was able to replicate normally, leading to elimination of the host culture in milk, which had been previously heat-treated. When raw milk was used under identical conditions, the phages were unable to replicate. Phage adsorption assays were performed and these demonstrated that adsorption of phage was significantly reduced in the raw milk while it was restored in the heat-treated sample (86.50% compared with 99.96% adsorption respectively). When confocal microscopy with a Live/Dead Bac light staining system was employed, it was observed that in raw milk S. aureus formed clusters associated with fat globules, while in heat-treated milk, bacterial agglutination had not occurred. CONCLUSIONS: Raw milk inhibits staphylococcal phage K proliferation. SIGNIFICANCE AND IMPACT OF THE STUDY: This observation has implications for the exploitation of staphylococcal therapeutic phage in milk.

Animals↗
PubMed2005

Isolation and characterization of two anti-staphylococcal bacteriophages specific for pathogenic Staphylococcus aureus associated with bovine infections.

AIMS: The aim of this study was to isolate and characterize bacteriophages against bovine Staphylococcus aureus associated with mastitis. METHODS AND RESULTS: We describe the isolation of two anti-staphylococcal phages namely DW2 and CS1 from farmyard slurry. Both phages were characterized by electron microscopy and restriction analysis and shown to belong to the Siphoviridae family. CS1 and DW2 were lytic for representatives of all three clonal groups of Irish mastitis-associated staphylococci. These phages were compared with the previously characterized Myoviridae phage K. Infusion of a cocktail of all three phages at 10(8) PFU ml(-1) into live cow teats resulted in no detectable increase in somatic cell counts in milks indicating that the phages did not irritate the animal. CONCLUSION: Two new anti-staphylococcal phages CS1 and DW2 were isolated and characterized and tested for immunogenicity in animal teats. SIGNIFICANCE AND IMPACT OF THE STUDY: The phages isolated in this study are active against pathogenic S. aureus and may be incorporated into teat-dips or teat-washes as a non-antibiotic prophylaxis against staphylococcal bovine mastitis.

Animals↗
PubMed2005

Potential of the polyvalent anti-Staphylococcus bacteriophage K for control of antibiotic-resistant staphylococci from hospitals.

The increasing prevalence of antibiotic-resistant staphylococci has prompted the need for antibacterial controls other than antibiotics. In this study, a lytic bacteriophage (phage K) was assessed in vitro for its ability to inhibit emerging drug-resistant Staphylococcus aureus strains from hospitals and other species of Staphylococcus isolated from bovine infections. In in vitro inhibitory assays, phage K lysed a range of clinically isolated methicillin-resistant S. aureus (MRSA) strains, S. aureus with heterogeneous vancomycin resistance and vancomycin resistance, and teicoplanin-resistant strains. In these assays, 14 of the MRSA strains were initially only weakly sensitive to this phage. However, propagation of phage K on these less-sensitive strains resulted in all 14 being sensitive to the modified phages. The results enforce the principle that, while certain target bacteria may be relatively insensitive to lytic phage, this can be overcome by obtaining modified phage variants from passage of the phage through the insensitive strains. Model in situ hand wash studies using a phage-enriched wash solution resulted in a 100-fold reduction in staphylococcal numbers on human skin by comparison with numbers remaining after washing in phage-free solution. Infusion of the phage into a nonimmunogenic bismuth-based cream resulted in strong anti-Staphylococcus activity from the cream on plates and in broth.

Animals↗
PubMed2005

The recombinant phage lysin LysK has a broad spectrum of lytic activity against clinically relevant staphylococci, including methicillin-resistant Staphylococcus aureus.

This study concerns the cloning, characterization, and expression of the lysin (LysK) from staphylococcal phage K in Lactococcus lactis. Lactococcal lysates containing recombinant LysK were found to inhibit a range of different species of staphylococci isolated from bovine and human infection sources, including methicillin-resistant Staphylococcus aureus. LysK thus has potential as an antimicrobial for applications in the prevention and/or treatment of infections caused by staphylococci.

Animals↗
PubMed2004

Genome of staphylococcal phage K: a new lineage of Myoviridae infecting gram-positive bacteria with a low G+C content.

Phage K is a polyvalent phage of the Myoviridae family which is active against a wide range of staphylococci. Phage genome sequencing revealed a linear DNA genome of 127,395 bp, which carries 118 putative open reading frames. The genome is organized in a modular form, encoding modules for lysis, structural proteins, DNA replication, and transcription. Interestingly, the structural module shows high homology to the structural module from Listeria phage A511, suggesting intergenus horizontal transfer. In addition, phage K exhibits the potential to encode proteins necessary for its own replisome, including DNA ligase, primase, helicase, polymerase, RNase H, and DNA binding proteins. Phage K has a complete absence of GATC sites, making it insensitive to restriction enzymes which cleave this sequence. Three introns (lys-I1, pol-I2, and pol-I3) encoding putative endonucleases were located in the genome. Two of these (pol-I2 and pol-I3) were found to interrupt the DNA polymerase gene, while the other (lys-I1) interrupts the lysin gene. Two of the introns encode putative proteins with homology to HNH endonucleases, whereas the other encodes a 270-amino-acid protein which contains two zinc fingers (CX(2)CX(22)CX(2)C and CX(2)CX(23)CX(2)C). The availability of the genome of this highly virulent phage, which is active against infective staphylococci, should provide new insights into the biology and evolution of large broad-spectrum polyvalent phages.

Amino Acid Sequence↗
PubMed2001

Continuous intrathecal baclofen infusion for children with cerebral palsy: a pilot study.

OBJECTIVES: To determine whether continuous intrathecal baclofen infusion (CIBI) would decrease spasticity and improve function in children with spastic cerebral palsy. DESIGN: Prospective study with measurement of changes from baseline assessed at regular intervals for 6 months following the intervention. PATIENTS: Two subjects aged 8 and 9 years with cerebral palsy. Inclusion criteria included severe spasticity and age greater than 4 years. STUDY CENTRE: Department of Rehabilitation, The Children's Hospital at Westmead, Westmead, New South Wales, Australia. RESULTS: Both subjects had clinically significant reductions in lower limb spasticity from a single intrathecal dose of baclofen (screening procedure), and had intrathecal pumps implanted. An intensive physical therapy programme was provided for both subjects in the 1-3-month period after commencing CIBI, in order to maximize functional gains. Modified Ashworth Scale scores remained reduced during the 6-month study period. There was a clinically significant increase in upper limb function for Subject 1. Gross Motor Function Measure scores decreased from 22% to 19% for Subject 1, and increased from 6% to 10% for Subject 2 over the study period. Paediatric Evaluation of Disability Inventory scores for Subject 1 showed a reduction in the level of caregiver assistance required, while Subject 2 showed significant improvement in the functional mobility domain. The major changes noted in the parent questionnaires were reduction in tone, increased range of motion and reduced time taken helping with activities of daily living such as toilet and dressing. No significant side-effect was seen after the screening procedure or after continuous intrathecal infusion. Both subjects' parents felt their child was improved following the intervention. CONCLUSIONS: Children with spastic cerebral palsy can have their spasticity effectively reduced with CIBI. In this study of two children, the clinical improvements were encouraging, and it is proposed that CIBI may be of benefit to those patients whose level of spasticity severely interferes with function. Further studies using multidimensional assessment approaches, with larger numbers of children, are warranted.

Baclofen↗
PubMed1987

Personal health records: an evaluation.

A cohort of mothers whose babies were born over one calendar month were followed up eight to 11 months after being given a personal health record for their newborn babies. Eight per cent of mothers lost the records and three more said they had not been given a record while in hospital; a total of 10% of mothers had either lost or misplaced the record. There were no particular demographic characteristics which identified the mothers who were more likely to lose the record. Most parents liked personal health records and used them frequently, as did the community health staff. Most private doctors, however, did not find them useful. Before wider distribution of such records is contemplated health workers should be adequately prepared, especially doctors in the private sector.

Attitude of Health Personnel↗
PubMed1986

Herpes simplex encephalitis in infants.

Two cases are reported of severe encephalitis in infants that were caused by a primary infection with herpes simplex virus type 1. Both patients presented with focal seizures; the clinical diagnosis was confirmed by the rapid appearance of IgM antibody to herpes simplex virus type 1 in cerebrospinal fluid and serum. In spite of the early use of acyclovir, which was administered by the intravenous route, the clinical response was poor and both infants were left with severe neurological impairment.

Acyclovir↗