Search PubMed⌕ Search

Biomedical subjects

D O'Neill

Publications and source records attributed to D O'Neill.

At least 109 records · Page 6Linked to original sources
PubMed1993

Parkinson's dementia and Alzheimer's dementia: an evoked potential comparison.

Auditory endogenous event-related potentials (ERPs) and flash visual evoked potentials (VEPs) were recorded in 26 elderly patients with idiopathic Parkinson's disease (PD), 14 with dementia and 12 non-demented, 16 elderly patients with Alzheimer dementia (AD) and 15 cognitively intact controls. ERP P3 and flash-VEP N2, P2 and delta (P2-P1) latency measures were significantly increased in the demented PD group compared with controls. The ERP P3 latency was also significantly delayed in the AD group compared with controls, but the differences in the flash-VEP measures from controls were not significant. No significant differences were noted between the PD groups, except for a significantly shorter flash-VEP N1 latency in the demented PD group; this was also the only significant evoked potential difference between the AD and PD dementia groups, which were otherwise electrophysiologically similar.

Aged↗
PubMed1992

Current uses of ophthalmic lasers.

Current laser treatments are quick, relatively painless, and well tolerated. Some ophthalmic techniques can be performed only by laser while others have a lower morbidity than alternative treatments. Peripheral retinal photocoagulation and focal photocoagulation now offer greatly improved visual prognosis for diabetic patients with proliferative diabetic retinopathy or diabetic macular disease. Selected cases of macular degeneration may be treated by focal laser photocoagulation. The role of lasers in treating sub-retinal neovascular membranes is limited by the extent and location of the membrane at presentation and the high risk of recurrence after treatment. Patients with distorted vision must be referred urgently for specialist ophthalmic assessment. Flat retinal holes and tears may be sealed by laser therapy, thus preventing retinal detachment. Short pulsed neodymium-YAG photodisruptive capsulotomy effectively clears the visual axis of thickened posterior lens capsule after cataract surgery. Short pulsed neodymium-YAG photodisruptive iridotomy may be used to treat and prevent angle closure glaucoma. Laser trabeculoplasty aids the control of open angle glaucoma. Research is continuing into the role of other lasers in managing open angle glaucoma and of photoablative lasers in treating refractive errors and superficial corneal disorders.

Cataract Extraction↗
PubMed1992

Physicians, elderly drivers, and dementia.

In western countries, the proportion of drivers who are elderly is increasing rapidly; over a quarter of the driving population will be 55 years of age or older by the year 2000. Although elderly drivers tend to drive less and may avoid night driving, the number of car accidents and the severity of injuries sustained in such accidents by distance driven increases strikingly after the age of 65. But how can doctors identify those elderly drivers who are a danger to themselves and others? And, once they are identified, how should clinicians balance the effects of removing a driving licence, which may greatly affect a patient's lifestyle, against public safety and breach of confidentiality if the patient refuses to give up his or her licence voluntarily? Medical decisions about illnesses that predispose to loss of consciousness are fairly clear-cut, but normal ageing processes and dementia can be much more difficult to identify and to assess; moreover, there seems little correlation between tests of mental performance and driving ability. Comparisons between practices in different countries may provide some answers, but the introduction of modified driving tests for elderly drivers with some evidence of mild impairment but who wish to retain their driving licence should be considered.

Accidents, Traffic↗
PubMed1992

Longitudinal diagnosis of memory disorders.

Early referral for specialist assessment is becoming more common with memory disorders and dementia: the mean Mini-Mental State Examination (MMSE) score of new patients at our clinic rose from 18.7 to 20.7 between 1986 and 1990. The clinical diagnosis of mild to moderate dementia has been recognized to be difficult, but several studies have reported cross-sectional diagnosis. We examined the number of visits required to establish a clinical diagnosis of dementia in the first 125 patients attending a Memory Disorders Clinic who had at least two visits (six months apart) and the stability of the diagnoses. Just under half of the patients required at least two visits to establish the clinical diagnosis. The MMSE was not a good guide to the number of visits required but the diagnosis at the first visit remained stable in all patients who scored < or = 10/30. Sixteen per cent of patients interchanged between the categories of Alzheimer's, mixed and vascular dementias. Possible age-associated memory impairment progressed to dementia in six of eight cases, and depression to dementia in three cases. The diagnosis of mild to moderate dementia should not be restricted to a cross-sectional approach, but should involve serial clinical, psychological and affective assessments.

Aged↗
PubMed1992

Spinal fusion for back pain: a clinical and radiological review.

Eighty-one patients who had spinal fusions performed for back pain over a 7-year period were reviewed; 74% were satisfied with the outcome of their surgery, mainly because of the degree of pain relief obtained. Based on lateral radiographs of the fusion area in flexion and extension, there was a 34% pseudarthrosis rate in first-time fusions. However, there was no clear relationship between the integrity of fusion and clinical success, indicating that many factors other than bony fusion influence the eventual outcome of the operation.

Adult↗
PubMed1992

Bronchial epithelial cells release neutrophil chemotactic activity in response to tachykinins.

The purpose of this study was to determine whether substance P (SP), neurokinin A (NKA), and neurokinin B (NKB) induce the release of neutrophil chemotactic activity (NCA) from bovine bronchial epithelial cells (BBEC) and whether neutral endopeptidase (NEP), a membrane-bound metalloenzyme that hydrolyzes tachykinins, modulates these effects. BBEC monolayers were exposed to SP, NKA, and NKB in the absence or presence of phosphoramidon (10(-6) M), a selective NEP inhibitor, for 72 h. Using a modified blind-well in vitro neutrophil chemotaxis assay, we found that tachykinin-exposed BBEC culture supernatant fluids induced significant neutrophil chemotaxis compared with supernatants obtained from unstimulated BBEC. Maximal effect was observed after 48 h of incubation and at SP concentration of 10(-13) M [92 +/- 3 (SP) vs. 64 +/- 2 (media) cells/high-power field (HPF), mean +/- SE, n = 7, P less than 0.05]. Release of NCA was mediated by the COOH-terminal of the SP molecule. The rank order of potency of tachykinins in inducing release of NCA was SP greater than NKA = NKB. SP-induced response was significantly potentiated by phosphoramidon (109 +/- 3 vs. 92 +/- 3 cells/HPF, n = 7, P less than 0.05), whereas other proteinase inhibitors had no effect. The released NCA was composed of protein and lipid-soluble components. These data indicate that mammalian tachykinins induce the release of NCA from BBEC and that NEP modulates these effects. We suggest that tachykinins regulate neutrophil recruitment into the lower respiratory tract, in part, by inducing the release of NCA from airway epithelial cells.

Animals↗
PubMed1992

Dementia and driving.

Many European countries test cars, but not their drivers, as they age. There is evidence to suggest that human factors are more important than vehicular factors as causes of motor crashes. The elderly also are involved in more accidents per distance travelled than middle-aged drivers. As the UK relies on self-certification of health by drivers over the age of 70 years, we examined the driving practices of patients with dementia attending a Memory Clinic. Nearly one-fifth of 329 patients with documented dementia continued to drive after the onset of dementia, and impaired driving ability was noted in two-thirds of these. Their families experienced great difficulty in persuading patients to stop driving, and had to invoke outside help in many cases. Neuropsychological tests did not help to identify those who drove badly while activity of daily living scores were related to driving ability. These findings suggest that many patients with dementia drive in an unsafe fashion after the onset of the illness. The present system of self-certification of health by the elderly for driver-licensing purposes needs to be reassessed.

Accidents, Traffic↗
PubMed1991

A preliminary evaluation of 566C80 for the treatment of Pneumocystis pneumonia in patients with the acquired immunodeficiency syndrome.

BACKGROUND: The drug 566C80 is an investigational hydroxynaphthoquinone that is active against Pneumocystis carinii in vitro and in animal models. Initial studies in humans indicate that 566C80 is safe and has adequate bioavailability after oral administration. METHODS: We conducted an open-label trial of 566C80 in 34 adults with the acquired immunodeficiency syndrome (AIDS) and untreated pneumocystis pneumonia. All the patients had a partial pressure of arterial oxygen of at least 60 mm Hg while breathing room air. They were enrolled sequentially in three cohorts taking 566C80 at different dosages, all administered orally: 750 mg three times daily for 5 days, then twice daily for 16 days; 750 mg three times daily for 21 days; and 750 mg four times daily for 21 days. RESULTS: All 34 patients survived, and 27 (79 percent) were successfully treated with 566C80 alone. The mean partial pressure of oxygen in 33 patients was 78 mm Hg at entry and 93 mm Hg after the course of 566C80 (P less than 0.001). In five patients (15 percent) the drug was discontinued because of lack of response. In four patients (12 percent), the drug was discontinued because of toxicity (fever and rash in two patients each). In two of these, treatment was considered to have succeeded because 566C80 was not discontinued because of toxicity until after day 14. Five of the successfully treated patients had rashes that resolved despite continued therapy. In nine patients, serum alanine aminotransferase levels rose above 100 U per liter. During the first three months after the completion of therapy, pneumocystis pneumonia recurred in 4 of the 27 successfully treated patients, and another 3 patients had recurrences between month 3 and month 6 of follow-up. The mean (+/- SEM) steady-state plasma levels of 566C80 were similar in the three cohorts: 16.3 +/- 2.10, 20.4 +/- 2.48, and 18.9 +/- 3.08 micrograms per milliliter in the patients taking the drug twice daily, three times daily, and four times daily, respectively. CONCLUSIONS: From these preliminary data, the investigational compound 566C80 appears to be a safe, effective, and well-tolerated therapy for P. carinii pneumonia of mild-to-moderate severity in patients with AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1991

A DNA-binding factor in adult hematopoietic cells interacts with a pyrimidine-rich domain upstream from the human delta-globin gene.

To date, DNA-binding factors with a developmental pattern of expression have not been described in human erythroid cells to explain the switch from fetal (gamma-) to adult (delta- and beta-) globin gene expression. Here we describe a factor present in nuclear extracts from adult mouse and human hematopoietic cells that binds to an oligopyrimidine repeat approximately 960 base pairs upstream from the human delta-globin gene. The binding site for the factor is within an unusual 250-base-pair domain that is greater than 95% pyrimidines on one strand. This domain is preferentially sensitive to S1 nuclease in supercoiled plasmids, indicating that it can adopt an alternative non-B-DNA conformation. A number of S1-sensitive sites within the domain, including the factor-binding site, have sequence characteristics associated with the formation of a triple helix (H-DNA). The position of the binding site between the fetal and adult beta-globin-like genes, its potential for adopting an unusual secondary structure, and the restricted activity of the binding factor to adult hematopoietic tissues suggest possible roles in hematopoietic cell development and hemoglobin switching.

Adult↗
PubMed1991

The beta globin 3' enhancer element confers regulated expression on the human gamma globin gene in the human embryonic-fetal erythroleukemia cell line K562.

We have constructed fusion genes comprised of gamma and beta globin elements and globin sequences linked to neomycin resistance (neoR) genes to define the cis acting sequences responsible for developmental stage-specific expression and induction of fetal globin genes in embryonic-fetal erythroleukemia K562 cells. The results indicate that the gamma promoter is required for proper initiation of transcription. However, the accumulation of gamma globin transcripts in response to hemin induction requires the additional presence of either gamma intervening sequence 2 or the 3' enhancer element of the beta globin gene. Thus, the gamma promoter may provide the elements for developmental stage-specific gene expression during fetal life. By contrast, the beta 3' enhancer is erythroid-specific but not developmental stage- or gene-specific.

Cloning, Molecular↗
PubMed1991

Attitudes of nursing and rest home administrators toward deinstitutionalized elders with psychiatric disorders.

The administrators of 92 nursing homes and rest homes in western Massachusetts were surveyed on their experiences with elderly residents with a history of psychiatric hospitalization and their willingness to admit such individuals in the future. A majority of those who had admitted deinstitutionalized elders with chronic psychiatric disorders reported having experienced severe problems with them. Most of the problems involved the resident going into crisis or producing some highly disruptive behavior. Although two-thirds of the facilities had admitted elders who had been deinstitutionalized from a public psychiatric hospital, only one-quarter clearly planned to do so in the future. Three quarters of the administrators reported that they did not have the support services that the deinstitutionalized elders in their facilities needed. A comparison of the services reported to be important and those reported to be available suggest that simply increasing the availability of psychiatric support services would probably not influence administrators to admit elders with chronic mental illness in the future.

Administrative Personnel↗