Biomedical subjects

J A Hiscox

Publications and source records attributed to J A Hiscox.

11 recordsLinked to original sources

PubMed2006

Cost savings and quality improvement--single-use suture instruments?

AIM: To determine if the instruments found in single-use suture kits are of satisfactory quality when compared with re-useable instruments and to determine the cost implications of changing to these kits. METHODS: Audit of established practice, followed by trial of new suture kits and their introduction to the department. The new practice was then audited. A cost analysis was conducted. RESULTS: The audit showed numerous problems with the traditional suture kits (instruments were breaking or no longer suitable for suturing wounds). A trial of single-use instruments demonstrated them to be high quality and provided new instruments each time. A repeat audit at one year post-introduction demonstrated no identifiable problem with the new suture kits. The subjective impression of staff was of an improvement compared to the old kits. Costs of sterilising suture instruments were determined and it was found that single use suture kits were cost effective. Assuming an average usage of 150 kits per month, at pound 4.45 each cost for sterilisation, and a total cost of pound 3.05 each for a single-use suture kit plus dressing pack per patient, this yielded a projected cost saving of pound 2520.00 per annum. The actual cost saving was pound 1981.00 that year. The shortfall was due to overestimation of average usage. CONCLUSION: Single use instruments would appear to be safe and cost effective in the emergency department setting.

Cost Savings↗

PubMed2002

The nucleolus--a gateway to viral infection?

A number of viruses and viral proteins interact with a dynamic sub-nuclear structure called the nucleolus. The nucleolus is present during interphase in mammalian cells and is the site of ribosome biogenesis, and has been implicated in controlling regulatory processes such as the cell cycle. Viruses interact with the nucleolus and its antigens; viral proteins co-localise with factors such as nucleolin, B23 and fibrillarin, and can cause their redistribution during infection. Viruses can use these components as part of their replication process, and also use the nucleolus as a site of replication itself. Many of these properties are not restricted to any particular type of virus or replication mechanism, and examples of these processes can be found in DNA, RNA and retroviruses. Evidence suggests that viruses may target the nucleolus and its components to favour viral transcription, translation and perhaps alter the cell cycle in order to promote virus replication. Autoimmunity to nucleolin and fibrillarin have been associated with a number of diseases, and by targeting the nucleolus and displacing nucleolar antigens, virus infection might play a role in the initiation of these conditions.

Amino Acid Sequence↗

PubMed2001

The coronavirus infectious bronchitis virus nucleoprotein localizes to the nucleolus.

The coronavirus nucleoprotein (N) has been reported to be involved in various aspects of virus replication. We examined by confocal microscopy the subcellular localization of the avian infectious bronchitis virus N protein both in the absence and in the context of an infected cell and found that N protein localizes both to the cytoplasmic and nucleolar compartments.

Amino Acid Sequence↗

PubMed2001

Localization to the nucleolus is a common feature of coronavirus nucleoproteins, and the protein may disrupt host cell division.

The subcellular localization of transmissible gastroenteritis virus (TGEV) and mouse hepatitis virus (MHV) (group I and group II coronaviruses, respectively) nucleoproteins (N proteins) were examined by confocal microscopy. The proteins were shown to localize either to the cytoplasm alone or to the cytoplasm and a structure in the nucleus. This feature was confirmed to be the nucleolus by using specific antibodies to nucleolin, a major component of the nucleolus, and by confocal microscopy to image sections through a cell expressing N protein. These findings are consistent with our previous report for infectious bronchitis virus (group III coronavirus) (J. A. Hiscox et al., J. Virol. 75:506-512, 2001), indicating that nucleolar localization of the N protein is a common feature of the coronavirus family and is possibly of functional significance. Nucleolar localization signals were identified in the domain III region of the N protein from all three coronavirus groups, and this suggested that transport of N protein to the nucleus might be an active process. In addition, our results suggest that the N protein might function to disrupt cell division. Thus, we observed that approximately 30% of cells transfected with the N protein appeared to be undergoing cell division. The most likely explanation for this is that the N protein induced a cell cycle delay or arrest, most likely in the G(2)/M phase. In a fraction of transfected cells expressing coronavirus N proteins, we observed multinucleate cells and dividing cells with nucleoli (which are only present during interphase). These findings are consistent with the possible inhibition of cytokinesis in these cells.

Animals↗

PubMed1999

Fingertip trauma in children from doors.

Fingertip and nailbed trauma caused by doors is common in children, occurring when fingers are either shut in the door itself or are trapped in the hinge as the door is closed. An audit was carried out over five months of all fingertip and nailbed injuries due to trauma from a door. One hundred and eighty eight children, 2% of all attendances in this period, had sustained such trauma, 39% of these occurring in children under four years of age. One hundred and forty seven children (75%) had sustained relatively minor soft-tissue injury to the finger, However the remaining forty seven (25%) of the injuries sustained were more serious e.g. Avulsion of the nail from the nailbed or amputation of part of the fingertip and 29 (15%) of all the cases required a general anaesthetic for exploration, cleaning and repair. The Plastic Surgery department followed up these 29 children and 71 Accident & Emergency follow-up appointments were generated by the remaining injuries. The incidence of significant injury was higher than expected and caused considerable distress to both the children and their parents, It is suggested that home safety protocols should feature advice on how to avoid these injuries.

Accidents, Home↗

PubMed1998

School referral survey.

Many schools refer children who have sustained an injury, directly to the local Accident & Emergency (A&E) department. This prospective study monitored these referrals for one school term (08.01.96-31.03.96). During this time 200 children under the age of 14 years presented from school to the A&E department of the Royal Aberdeen Childrens Hospital (RACH). The majority presented with trivial or mild injuries and 45% of parents felt that attending A&E was inappropriate. Half the accidents happened to unsupervised children. Rural children and children of working parents were less likely to attend A&E. In Grampian Region school referrals to A&E generate a significant workload for the A&E department with resultant cost implications. It would appear that a large number of these attendances are medically unnecessary and result from a desire by the school to avoid any complaint or litigation.

Absenteeism↗

PubMed1997

Cotranslational disassembly of flock house virus in a cell-free system.

Intact, purified particles of the nodaviruses flock house virus and nodamura virus that were either transfected into cells that were resistant to infection or introduced into in vitro translation systems directed the synthesis of viral proteins. We infer that direct interaction of these nodavirus particles with cytoplasmic components mediated virion disassembly that resulted in release of the viral RNA.

Animals↗

PubMed1995

Characterization of the transmissible gastroenteritis virus (TGEV) transcription initiation sequence. Characterization of TGEV TIS.

The ability of the TGEV transcription initiation sequence (TIS) to produce subgenomic RNAs was investigated by placing a reporter gene, chloramphenicol acetyltransferase (CAT) under the control of either the mRNA 6 or the mRNA 7 TISs. Both constructs only produced CAT in TGEV infected cells and the amount of CAT produced from the mRNA 7 TIS was less than from the mRNA 6 TIS. Mutations were made within and around the TISs and the effect on CAT production assayed. THe results showed that the TGEV TIS acted as a initiator of transcription for CAT, though the degree of base pairing between the TIS and leader RNA was not the only factor implicated in the control transcription.

Animals↗

PubMed1995

Quantification of individual subgenomic mRNA species during replication of the coronavirus transmissible gastroenteritis virus.

A biotinylated-oligonucleotide-based method was used to isolate the subgenomic mRNAs of the coronavirus transmissible gastroenteritis virus (TGEV) to investigate the amounts of the mRNAs produced at early, middle and late times in the replication cycle. TGEV mRNA 6, which encodes the N protein, was observed to be the most abundant species throughout the replication cycle. The ratios of mRNA 6 to the other mRNAs were 1:0.11 (mRNA 2), 1:0.16 (mRNAs 3 and 4) and 1:0.37 (mRNA 5) at 12 h post-infection. All the mRNA species were differentially regulated throughout the replication cycle, although the rate of accumulation of mRNAs 4, 5 and 6, but not mRNA 3, increased markedly towards the end of the replication cycle. mRNA 7 was not detected in the system used. There was no observable correlation between the amounts of each mRNA synthesised and the potential degree of base pairing between the 3' end of the leader sequence and the transcription associated sequences on the genomic RNA at any time during the replication cycle. This indicates that the extent of base pairing was not the only factor involved in the control of subgenomic mRNA synthesis.

Animals↗

PubMed1995

Investigation of the control of coronavirus subgenomic mRNA transcription by using T7-generated negative-sense RNA transcripts.

The subgenomic mRNAs of the coronavirus transmissible gastroenteritis virus (TGEV) are not produced in equimolar amounts. We have developed a reporter gene system to investigate the control of this differential subgenomic mRNA synthesis. Transcription of mRNAs by the TGEV polymerase was obtained from negative-sense RNA templates generated in situ from DNA containing a T7 promoter. A series of gene cassettes was produced; these cassettes comprised the reporter chloramphenicol acetyltransferase (CAT) gene downstream of transcription-associated sequences (TASs) (also referred to as intergenic sequences and promoters) believed to be involved in the synthesis of TGEV subgenomic mRNAs 6 and 7. The gene cassettes were designed so that negative-sense RNA copies of the CAT gene with sequences complementary to the TGEV TASs, or modified versions, at the 3' end would be synthesized in situ by T7 RNA polymerase. Using this system, we have demonstrated that CAT was expressed from mRNAs derived from the T7-generated negative-sense RNA transcripts only in TGEV-infected cells and only from transcripts possessing a TGEV negative-sense TAS. Analysis of the CAT mRNAs showed the presence of the TGEV leader RNA sequence at the 5' end, in keeping with observations that all coronavirus mRNAs have a 5' leader sequence corresponding to the 5' end of the genomic RNA. Our results indicated that the CAT mRNAs were transcribed from the in situ-synthesized negative-sense RNA templates without the requirement of TGEV genomic 5' or 3' sequences on the T7-generated negative-sense transcripts (3'-TAS-CAT-5'). Modification of the TGEV TASs indicated (i) that the degree of potential base pairing between the 3' end of the leader RNA and the TGEV negative-sense TAS was not the sole determinant of the amount of subgenomic mRNA transcribed and (ii) that other factors, including nucleotides flanking the TAS, are involved in the regulation of transcription of TGEV subgenomic mRNAs.

Animals↗

PubMed1995

Genetic modification and selection of microorganisms for growth on Mars.

Genetic engineering has often been suggested as a mechanism for improving the survival prospects of terrestrial microoganisms when seeded on Mars. The survival characteristics that these pioneer microorganisms could be endowed with and a variety of mechanisms by which this can be achieved are discussed, together with an overview of some of the potential hurdles that must be overcome. Also, a number of biologically useful properties for these microorganisms are presented that could facilitate the initial human colonisation and ultimately the planetary engineering of Mars.

Bacteria, Anaerobic↗