Search PubMed⌕ Search

Biomedical subjects

P Bates

Publications and source records attributed to P Bates.

At least 73 records · Page 4Linked to original sources
PubMed1992

Enhanced levels of radiation-induced G2 phase delay in ataxia telangiectasia heterozygotes.

Ataxia telangiectasia (AT) is a multiform genetic disease characterized by immunodeficiency, cerebellar abnormalities, and cancer predisposition. Heterozygotes also have an increased risk of developing several different cancers. It has been estimated that as many as 18% of all patients with breast cancer, the cancer most clearly associated with AT heterozygotes, may be carriers of the AT gene. We describe an assay for AT heterozygotes that relies on the previous observation that cells from AT homozygotes show a greater and more prolonged radiation-induced accumulation in the G2 phase of the cell cycle than do normal controls. We showed that all 6 A-T heterozygotes show a greater extent of G2 phase delay at different times postirradiation than do controls. The degree of accumulation was less than that observed in AT homozygotes. Only two of 22 controls showed overlap with heterozygotes at 18 hours postirradiation, and that number was reduced to one at the 24-hour point. As a group, AT heterozygotes were intermediate between controls and AT homozygotes at both time points after irradiation. This assay is relatively simple and reliable and can be performed in any laboratory with access to both Epstein-Barr virus (EBV) for transformation of lymphocytes and a fluorescence-activated cell analyzer.

Ataxia Telangiectasia↗
PubMed1992

Defining death, natural death legislation and withdrawal of treatment.

This article summarises and comments on a number of legal developments (legislation and judicial precedents) in Australia and England in recent years concerned with definitions of death, and withdrawal of life-preserving treatment. The general thrust of these developments and other proposed legislation is four-fold: (i) to respond to technological advances in clinical medicine; (ii) to strengthen patient rights of autonomy and self-determination in the right to refuse treatment; (iii) to reflect a shift in dominant community attitudes and social morality, and to approximate more closely to common clinical practices, which take account of 'quality-of-life' considerations as well as 'sanctity of life' in decision-making for patients unable to express a view because of youth or impaired mental capacity; (iv) to give a greater certainty and legal guidance to clinicians, and to give legal protection to clinicians who follow certain decision-making procedures.

Adult↗
PubMed1991

Quickscan: Doppler ultrasound emulation of angiography--its value prior to arteriography in peripheral vascular disease.

The prevalence of peripheral vascular disease demands a quick, reliable, non-invasive technique for initial assessment. We have devised a new method which combines the two physical principles that (1) Doppler shift is proportional to blood velocity and (2) blood velocity is inversely proportional to arterial cross-section with the ability to track probe position using a non-contacting method. An image of the probe track and any arterial narrowing is shown superimposed on an outline of the patient. Pressure measurement, scan and graphics with final report take about 20 minutes. The accuracy of this system in peripheral vascular disease was evaluated. Thirty-one patients underwent quickscan (QS) and arteriography within an average time of 7 days. Abdominal aorta, common iliac-common femoral, superficial femoral and popliteal artery segments were graded independently as normal, significant stenosis (greater than 50% of diameter) or occluded by both techniques. Of 197 segments, QS correctly assessed 106 normal, 22 stenosed and 28 occluded segments. Four equivocal angiographic stenoses were normal on QS and three severe stenoses were graded occlusion. Fifteen segments on angiography and five on QS were not assessed. For the iliac and superficial femoral artery segments, sensitivity and specificity averaged 77% and 86%, respectively, for all grades. Aortic statistics were invalid (only one significant lesion). Six out of eight popliteal occlusions were correctly diagnosed by QS, but no popliteal stenoses were detected out of six shown on arteriography. Low numbers may contribute to this discrepancy but an improved popliteal scanning method may be necessary. We find initial QS an invaluable aid to direct percutaneous angiography and to indicate potential sites for angioplasty.

Adult↗
PubMed1991

Rapid assessment of literacy levels of adult primary care patients.

Health education materials, medical instructions, consent forms, and self-report questionnaires are often given to patients with little regard for their ability to read them. Reading ability is rarely tested in medical settings. The Rapid Estimate of Adult Literacy in Medicine (REALM) was developed as a quick screening tool to assist physicians in identifying patients with limited reading skills and in estimating patient reading levels. This information can be used to tailor materials and instructions to patients' abilities. The REALM and the reading sections of the Peabody Individual Achievement Test-Revised and the Slosson Oral Reading Test were used to test reading ability in 207 adults in six public and private primary care clinics. REALM scores correlated highly with those of the standardized reading tests. The REALM, which takes three to five minutes to administer and score, appears to be a practical instrument to estimate patient literacy in primary care, patient education, and medical research.

Adolescent↗
PubMed1990

Efficient incorporation of human CD4 protein into avian leukosis virus particles.

Virus envelope (Env) proteins are thought to contain specific signals for selective uptake by virus particles. In the course of attempting to define these signals by testing virus incorporation of CD4-Env chimeric proteins, normal human CD4 was found to be efficiently and selectively assembled into avian leukosis virus particles in quail cells. Viruses bearing CD4 at their surface may be useful reagents in the design of retrovirus-mediated gene therapy for the acquired immune deficiency syndrome.

Animals↗
PubMed1989

Normal inhibition of DNA synthesis following gamma-irradiation of radiosensitive cell lines from patients with Down's syndrome and Alzheimer's disease.

Inhibition of DNA synthesis was studied in gamma-irradiated lymphoblastoid cells from patients with Alzheimer's disease and Down's syndrome. A normal biphasic pattern of inhibition was observed over a dose range of 0-4 krad of gamma-rays in all of the cell lines. 3 out of 4 Down's and all the Alzheimer's cell lines were shown to be hypersensitive to ionizing radiation based on induced chromosomal aberrations. Increased G2 phase delay, comparable to that occurring in ataxia-telangiectasia cells, was observed for some of the cell lines, after exposure to gamma-rays. Contrary to other data in the literature these results demonstrate that radioresistant DNA synthesis is not an intrinsic feature of all disorders characterized by radiosensitivity.

Alzheimer Disease↗
PubMed1987

Painful bladder disease: clinical and pathoanatomical differences in 115 patients.

The diagnostic criteria for interstitial cystitis considered as a subgroup of painful bladder disease (that is sensory bladder disease and chronic abacterial cystitis) are not well established. Some urologists rely on symptoms, while others rely on cystoscopic appearance or pathological findings. Among 115 patients with painful bladder disease we compared symptoms, and cystoscopic and urodynamic findings in those with and without detrusor mastocytosis (28 or more mast cells per mm.2) and attempted to elucidate possible differences between the groups. We chose the pathological anatomical criterion of detrusor mastocytosis to be diagnostic for interstitial cystitis. A total of 43 patients had detrusor mastocytosis and other pathological anatomical signs of interstitial cystitis, and 72 had no mastocytosis but the pathological diagnoses of chronic unspecific cystitis, fibrosis of the bladder, detrusor myopathy, intestinal metaplasia and normal findings. When the 2 groups of patients were compared we found no differences in regard to symptoms (pain, dysuria, frequency, nocturia and urgency), frequency of allergy and hysterectomy, duration of symptoms, petechial bleeding during cystoscopy with bladder distension and cystometric findings. The patients with mastocytosis differed from those without mastocytosis in that they were older, and had a higher frequency of hematuria, a higher frequency of a red, scarred and richly vascularized bladder at cystoscopy before distension, and a smaller cystoscopic bladder capacity. We conclude that by dividing patients with painful bladder into 2 groups according to the mast cell counts in the detrusor, certain differences in the clinical findings in the groups can be ruled out. However, in individual patients one cannot note with certainty to which pathological anatomical group the patient belongs, since great overlapping between the groups exists. Whether only patients with detrusor mastocytosis have interstitial cystitis depends on definitions and still remains an open question.

Adult↗
PubMed1987

A prospective double-blind clinically controlled multicenter trial of sodium pentosanpolysulfate in the treatment of interstitial cystitis and related painful bladder disease.

Painful bladder disease, sensory bladder disease, chronic abacterial cystitis and interstitial cystitis are ill-defined conditions of unknown etiology and pathogenesis, and, therefore, they are without any rational therapy. Pathogenetic theories concerning defects in the epithelium and/or mucous surface coat (including glycosaminoglycans) of the bladder, and theories concerning immunological disturbances predominate. Sodium pentosanpolysulfate (Elmiron) acts by substituting a defective glycosaminoglycan layer and inhibits complement reactions in inflammatory processes. We compared sodium pentosanpolysulfate versus placebo in a prospective double-blind, clinically controlled multicenter trial of 115 patients with painful bladder disease. Two protocols were used. Protocol A included 43 patients with clinically and pathologically anatomically verified interstitial cystitis (28 or more mast cells per mm.2), and protocol B included 72 patients with a painful bladder and unspecific histological findings. The patients were randomized to receive either sodium pentosanpolysulfate (200 mg. twice daily) or placebo capsules for 4 months. Before and after the trial the patients were evaluated with symptom grading, urodynamics and cystoscopy with distension and deep bladder biopsies. The results showed no difference between the pre-trial and post-trial values in the sodium pentosanpolysulfate and placebo groups in both protocols in regard to symptoms, urodynamic parameters, cystoscopic appearance and mast cell counts. A significant increase in the cystoscopically determined bladder capacity in the sodium pentosanpolysulfate group in protocol A was found. We conclude that no statistically or clinically significant effect of sodium pentosanpolysulfate was found compared to placebo in patients with painful bladder disease.

Adult↗
PubMed1985

Shin splints--a literature review.

"Shin splints" is not a specific diagnosis. It is merely a descriptive term that describes chronic exertional shin pain in an athlete. The evidence seems clear that shin splint pain has many different causes and this reflects the variation in the anatomy. It would be preferable to describe shin splint pain by location and aetiology, for example, lower medial tibial pain due to periostitis or upper lateral tibial pain due to elevated compartment pressure. This would aid communication between physicians and also direct therapy more accurately.

Athletic Injuries↗