PubMed HealthSearch

Biomedical subjects

K O'Neill

Publications and source records attributed to K O'Neill.

At least 19 recordsLinked to original sources

Capillary electrophoresis using diol-bonded fused-silica capillaries.

In this paper, 3-glycidoxypropyltrimethoxysilane was used to produce diol-bonded capillaries at room temperature for capillary electrophoresis (CE). A variety of standard reference compounds and authentic biological samples including ribonucleotides, peptides and proteins were used to test the columns. It was found that greatly suppressed electroosmotic flow was measured over a pH range of 3-10. Lower than 1.6% relative standard deviation (> 10 runs) in migration time was observed for the analysis of test proteins. For real samples of ribonucleotides in tumor cell extracts, approximately 1 million theoretical plates and excellent peak shapes were obtained. The high column efficiency and symmetrical peaks allowed the separation of samples with only 0.6% maximum difference in migration times. The diol-bonded fused-silica capillary columns were stable when used in a pH range of 2-8 under typical CE conditions. The column preparation method involved a simple dynamic coating procedure at room temperature, greatly simplifying the more typical static coating methods that require vacuum pumps and ovens.

Amino Acid Sequence

Vasopressin-induction of the immediate early gene, NGFI-A, in cultured hippocampal glial cells.

Our earlier autoradiographic work had documented a wide distribution of vasopressin receptors in the hippocampus [R.E. Brinton, K.W. Gee, J.K. Wamsley, T.P. Davis, H.I. Yamamura, Regional distribution of putative vasopressin receptors in rat brain and pituitary by quantitative autoradiography, in: Proc. Natl. Acad. Sci. USA, 81 (1984) pp. 7248-7252; C. Chen, R.D. Brinton, T.J. Shors, R.F. Thompson, [Arg 8]-Vasopressin-induction of long lasting potentiation of synaptic transmission in the dentate gyrus, Hippocampus 3 (1993) 193-203.] which suggested the possibility that receptors for vasopressin were present in both neurons and glia. In the periphery, vasopressin is a potent mitogen in select proliferative cell types [E. Rozengurt, A. Legg, P. Pettican, Vasopressin stimulation of mouse 3T3 cell growth, Proc. Natl. Acad. Sci. USA, 76 (1979) pp. 1284-1287.] which also suggested a possible association between vasopressin receptor activation and the proliferative capacity of astrocytes. We therefore investigated whether vasopressin would induce the expression of the immediate early response gene, NGFI-A (also known as zif/268, ZENK, egr-1, krox 24), which is associated with initiation of mitogenesis [M. Sheng, M.E. Greenberg, The regulation and function of c-fos and other immediate early genes in the nervous system, Neuron, 4 (1990) pp. 477-485.]. Cultured hippocampal glial cells were exposed to vasopressin or a selective V1 vasopressin receptor agonist and in situ hybridization for NGFI-A mRNA was conducted. Results of these experiments demonstrated that vasopressin induced a highly significant dose-dependent increase in the number of cells expressing NGFI-A. Studies to determine the receptor subtype mediating vasopressin induction of NGFI-A were conducted utilizing the specific V1 agonist, [Phe2, Ile3, Orn8]-vasopressin. The V1 receptor agonist induced a highly significant dose dependent increase in the number of grains per NGFI-A positive cell. Time course analysis demonstrated that V1 agonist induction of NGFI-A occurred within 5 min, was maximally induced at 15 min of exposure and exhibited a gradual decline within 30 min of exposure which continued to decline over the 60 min time course. Glial cell responsivity was selective in that vasopressin and V1 agonist induction of NGFI-A occurred in a subpopulation of glial cells. Within a sea of glial cells, vasopressin and V1 agonist would induce islands of NGFI-A positive cells. Results of combined immunocytochemical labeling for the astrocyte specific marker, GFAP, and in situ hybridization for NGFI-A demonstrated that V1 agonist-induced NGFI-A expression occurred in GFAP positive cells. We observed no evidence for V1 agonist induction of NGFI-A in neurons. Collectively, these data document that vasopressin, acting via V1 vasopressin receptors, induces a highly significant increase in NGFI-A expression in select GFAP positive hippocampal astrocytes. To our knowledge, these data are the first report of a vasopressin mediated response in hippocampal glial cells. The potential functional significance of these findings is discussed.

Animals

Evaluation of a nurse-led continence service in the south-west of Glasgow, Scotland.

This paper reports the results of a pilot study of a nurse-led continence promotion service in both the community and a local nursing home. Telephone and written referrals were made to the service from 28 primary care teams in Glasgow, Scotland. In the nursing home all patients were assessed and an appropriate management plan implemented. A full assessment was carried out in all community patients, including an appraisal of contributory factors, urinalysis and diaries of food and drink intake. A management plan suited to the patient was then implemented. Patients' levels of incontinence in both arms of the study were assessed objectively using the Lagro-Janssen method. The cost incurred in both arms of the study were measured. There was a 69% improvement in the level of incontinence in the community group compared with 30% in the residents wing and 13% in the hospital wing. The savings in the nursing home amounted to Pounds 4152 in the residents' wing and Pounds 1959 in the hospital wing. In summary, a nurse dedicated to urinary incontinence in the community allows improved management, a greater level of awareness and results in resource savings, whilst increasing patient accessibility to a service.

Aged

Making the most and making sense: ethnographic research on spirituality in palliative care.

Presents ethnographic research on spirituality in palliative care. Reviews the literature and interviews palliative care staff along with their patients. Discovers two dominant themes in the literature and interviews with staff and patients around spirituality: making the most of it now and making sense. Discusses findings and suggests implications for the practice of spiritual care.

Anthropology, Cultural

Alcohol consumption and blood pressure in recently hospitalised patients.

One-thousand-four-hundred-and-fifty-three patients admitted to a teaching hospital, haemodynamically stable and not severely ill nor in significant pain, were interviewed within 48 h of admission and demographic data and a detailed drinking history were obtained. Supine blood pressures (BP) were recorded on the day following admission. The mean age of the population was 60.5 +/- 19.9 years (range 16-99 years) and the mean reported alcohol consumption was 67.8 +/- 273 g/week (range 0-6125 g/ week). Thirty-six percent of patients were currently receiving antihypertensive drug therapy. On multivariant analysis, reported alcohol intake was not significantly related to systolic BP (beta = 0.000, p = 0.902) or diastolic BP (beta = 0.028, p = 0.281). Age (beta = 0.331, p = 0.0001) and body weight (beta = 0.121, p = 0.0002) were significant independent predictors of systolic BP, and body weight was a significant independent predictor of diastolic blood pressure (beta = 0.207, p < 0.0001). A relationship between alcohol consumption and blood pressure was not apparent in this population of patients following admission to hospital. A positive association between alcohol consumption and blood pressure may not be a universal finding and may be contributed to by a "white coat" effect.

Adolescent

Postmortem sperm procurement.

PURPOSE: We determined the prevalence of requests for postmortem sperm procurement and the degree to which procurement is performed by those working in the field of infertility. MATERIALS AND METHODS: Structured telephone interviews were conducted with personnel at 273 assisted reproductive facilities in the United States and Canada. The number of facilities reporting requests and the number of facilities reporting that they performed the procedure were determined. RESULTS: The prevalence of requests for postmortem sperm procurement was much greater than initially anticipated. A total of 82 requests was reported at 40 facilities in 22 different states between 1980 and 1995. More than half of the reported requests (43) were made between 1994 and 1995. Of the 82 requests 25 were honored at 14 facilities in 11 different states. No requests or procedures were reported from Canada. CONCLUSIONS: Medical advances in postmortem sperm procurement, cryopreservation and in vitro fertilization permit retrieval of sperm after death for various purposes, including posthumous fatherhood. There are no explicit ethical guidelines, legislation or relevant case law, and fertility specialists must confront these issues before proceeding in a field fraught with moral and policy uncertainties.

Cadaver

Improving management of anemia using CQI techniques.

During the last two years, the National Kidney Foundation's Dialysis Outcomes Quality Initiative (NKF-DOQI) Anemia Work Group has been developing clinical practice guidelines for the management of anemia in patients with chronic renal failure. After an in-depth critical analysis of the scientific literature, with a consensus of "expert opinion" used to support recommendations in areas with inadequate published data, evidence-based guidelines were developed. These clinical practice guidelines, regardless of how well-founded in scientific evidence, are likely to be disregarded if they are not applicable in the day-to-day care of patients. Thus, they must be practical, clearly stated, and usable, given available resources and constraints. The purpose of this article is to describe our experiences in implementing some of these guidelines over the last two years, as they were being developed, for the care of patients in our hemodialysis unit.

Anemia

Benzodiazepine prescribing in a Sydney teaching hospital.

OBJECTIVES: To determine the pattern of benzodiazepine prescribing in hospital and at discharge in relation to prior benzodiazepine therapy. DESIGN: Patient interview within 48 hours of admission to determine benzodiazepine, alcohol and other psychotropic drug use before admission and review of medical records after discharge to document drugs prescribed in hospital and at discharge. SETTING: Tertiary teaching hospital, January to August 1995. RESULTS: 1453 patients (mean age, 60 [SD, 19] years; 52.7% female) were interviewed; 277 patients (19.1%) were taking benzodiazepines regularly (one or more doses per week) before admission. Of these, 28.5% did not have benzodiazepine therapy continued while in hospital and 63.9% did not receive benzodiazepines at the time of discharge. Of the remaining 1176 patients (those not previously taking benzodiazepines), 277 (23.6%) were prescribed them for the first time in hospital and 5.3% received benzodiazepines at the time of discharge. Older age, female sex, marital status (single, divorced or widowed) and the use of antidepressants and Schedule 8 narcotic analgesics were all statistically significant predictors of benzodiazepine use before admission, but alcohol consumption was not. CONCLUSIONS: A substantial number of patients do not have their benzodiazepine therapy continued in hospital and at the time of discharge, and are thus at risk of developing benzodiazepine withdrawal syndromes, including delirium. A small but clinically significant number of patients who do not usually take benzodiazepines receive them at the time of discharge and may be at risk of becoming long term users.

Anti-Anxiety Agents

Evaluation of a cognitive-behavioural intervention for pregnant injecting drug users at risk of HIV infection.

Pregnant injecting drug users were randomly assigned to: (i) individually receive a six-session cognitive-behavioural intervention in addition to their usual methadone maintenance treatment (intervention condition (I) (n = 40)); or (ii) their usual methadone maintenance treatment only (control condition (C) (n = 40)). There was no change in drug use per se in either group after the intervention. However, at 9-month follow-up the I group had significantly reduced some HIV risk-taking behaviours (in particular injecting risk behaviours). The I group reduced the needle risk associated both with "typical" use (drug use in the month before interview) and "binge" use (drug use in the month nominated as the heaviest month of drug use in the previous 6 months). The intervention had no effect on sexual risk behaviours. The finding of reduced injecting risk behaviour following the six-session intervention suggests that such an intervention may be of benefit for individuals persisting with injecting risk behaviours despite methadone maintenance treatment and the availability of sterile injection equipment.

Adult

The influence of gamma radiation and substrate on mycotoxin production by Fusarium culmorum IMI 309344.

Mycotoxin production (deoxynivalenol (DON), acetyl deoxynivalenol (A DON) and zearalenone) by Fusarium culmorum inoculated on to maize (heat sterilized, irradiation sterilized and non-sterile) and irradiated to 1 kGy or 3 kGy, or unirradiated, was investigated over a period of time. Lowest mycotoxin production was observed on non-sterile maize which may be due to the presence of a competitive microflora on non-sterile maize which may be due to the presence of a competitive microflora on non-sterile maize. In general, mycotoxin production was higher on heat-sterilized grain as compared to irradiation-sterilized maize. It was suggested that this pattern of mycotoxin production was possibly caused by changes in the grain brought about by autoclaving, which favoured mycotoxin production and possibly induced changes in irradiation-sterilized maize which inhibited mycotoxin production. On sterile maize, there was no significant difference in DON production by unirradiated, 1 kGy and 3 kGy irradiated cultures up to 56 d of incubation; between days 56 and 77 of incubation, DON production increased rapidly with largest increases occurring in irradiated (1 kGy and 3 kGy) cultures. On non-sterile grain, neither DON nor A DON were detected in unirradiated cultures of F. culmorum but were detected in cultures irradiated to 1 kGy and 3 kGy. In practice grain should be stored under conditions of temperature and moisture content which prevent fungal growth. However, in this study, the grain was stored under conditions that were approaching ideal for growth of the test organism. The results highlight that irradiation disinfestation of grain must be combined with good grain handling practices so that excessive mycotoxin production can be prevented during storage.

Fusarium

[Update on the dracunculosis eradication program].

Dracunculiasis has been described since antiquity and will be forever associated with the image of the method of extraction consisting of winding a few centimeters of the worm around a stick every day. For nearly ten years a worldwide effort to eradicate this infection has been under way. Achieving this apparently simple goal is hindered by the difficulties in accessing infected areas and by the dire poverty in the regions involved which include the "poorest of the poor". Spectacular results have been accomplished in Pakistan thanks to the concerted efforts of political, financial, and technical officials from a number of national and international organization. While the rate of infestation has decreased by 90% worldwide, the final push to complete eradication is the most difficult and, as in India and Mali, is being oriented towards a strategy involving an integrated approach. Results are slow and gradual but notable and durable progress has been made in terms of village water supply. It is necessary that intervention in these areas be associated with other poverty-fighting programs. Successful eradication without accompanying improvements would be a technical victory but in terms of public health and welfare such a victory would correspond to an unjustifiably missed opportunity.

Dracunculiasis

Etodolac selectively inhibits human prostaglandin G/H synthase 2 (PGHS-2) versus human PGHS-1.

The isozymes of prostaglandin G/H synthase (PGHS) are shown to be differentially inhibited in vitro by currently marketed nonsteroidal anti-inflammatory drugs (NSAIDs) using microsomal rhPGHS-1 and rhPGHS-2. Comparison of selectivity ratios (IC50 rhPGHS-1/IC50 rhPGHS-2) demonstrated a 10-fold selectivity of etodolac (Lodine) for rhPGHS-2, whereas the other NSAIDs evaluated demonstrated no preference or a slight preference for inhibition of rhPGHS-1. In vitro enzyme results were supported by a human whole blood assay where etodolac also demonstrated a 10-fold selectivity for inhibition of PGHS-2 mediated TxB2 production. Taken together, these data may be key to explaining the clinically observed gastrointestinal safety of etodolac versus other marketed NSAIDs.

Anti-Inflammatory Agents, Non-Steroidal

Analysis of nucleotide pools in human lymphoma cells by capillary electrophoresis.

Capillary electrophoresis is applied to determine nucleotide pool levels in human Burkitt lymphoma cells. The analysis was performed on a 65 cm x 50 microns I.D. Ucon-coated column with on-column UV detector. The method requires only nanoliters of sample and a simple sample preparation procedure. Over 12 nucleotides were separated and quantitated with high resolution and reproducibility. The whole capillary electrophoretic separation time was only 35 min. These results demonstrate that capillary electrophoresis provides a useful and easy way to analyze nucleotide pools in cells.

Adenine Nucleotides