PubMed HealthSearch

Biomedical subjects

A B Shaw

Publications and source records attributed to A B Shaw.

At least 19 recordsLinked to original sources

Non-therapeutic (elective) ventilation of potential organ donors: the ethical basis for changing the law.

Non-therapeutic ventilation of potential organ donors would increase the supply of kidneys for transplantation. There are no major ethical objections to it. The means of permitting it are forbidden by laws with an ethical basis. A law permitting it would need an ethical basis. Introducing a third legal method of diagnosing death would be unethical. Expanding the power of the advance directive to permit procedures involving minimal harm would be ethical but not helpful. Extending the power of proxies to permit specific non-therapeutic procedures which caused or risked minimal harm to incompetent patients is the best way forward.

Brain Death

Age as a basis for healthcare rationing. Support for agist policies.

It is inevitable that publicly funded, technically sophisticated medical treatments will be increasingly rationed. Other things being equal, there is a greater duty to use them to prolong the lives of younger than older people. Age is therefore an ethical rationing criterion. Denial of this may actually harm older people.

Aged

Acts of commission, omission, and demission or pulling the plug.

The difference between withholding and withdrawing treatment and actively killing is analysed. The intention of the physician and the effect on the patient are similar but the wider effect on others is different. The harmful effects of withdrawing life-preserving treatment which is no longer beneficial can be reduced by clarification of its purpose. This is to prolong life with value to the patient not just existence.

Ethics, Medical

In defence of ageism.

Health care should be preferentially allocated to younger patients. This is just and is seen as just. Age is an objective factor in rationing decisions. The arguments against 'ageism' are answered. The effects of age on current methods of rationing are illustrated, and the practical applications of an age-related criterion are discussed. Ageist policies are in current use and open discussion of them is advocated.

Aged

Quantification of proteinuria: a re-evaluation of the protein/creatinine ratio for elderly subjects.

The difficulties of 24-hour urine collection are well recognized, especially for elderly people for whom a means of estimating protein excretion from a single casual unit sample would be preferable. We compared measurement of total urinary protein estimated by the protein/creatinine ratio with 24-h urine collection and examined the role of the ratio in discriminating between clinically important levels of proteinuria. Although the protein/creatinine ratio appeared to have an excellent correlation with the 24-h collection, the absolute agreement between the two methods was poor. However, the clinical role of the protein/creatinine ratio as a semi-quantitative test of proteinuria remained, provided adjustment for expected creatinine excretion was made.

Aged

Assessment of protein intake in early progressive renal disease.

Mean protein intake in a 4-day dietary survey of 34 patients with early renal disease was 1.2 +/- 0.27 g/kg ideal body weight daily. Nine subjects were taking over twice the recommended minimum intake. An increased protein intake was associated with a greater phosphate and sodium intake and an increased excretion of urea, phosphate, and sodium. Daily intake fluctuated markedly during the study (coefficient of variance 22.5 +/- 10.9%). Protein catabolic rate calculated from urea excretion correlated with protein intake, r = 0.60. Mean difference between the two estimates was 0.04 +/- 0.28 g/kg per day. It is proposed that if urea excretion exceeds 4.5 mmol/kg per day in a single collection (protein catabolic rate 0.98 g/kg per day), serial measurements should be made to determine protein intake more accurately and give dietary advice.

Adult

Which urine sample for detection of proteinuria?

The standard practice of screening for proteinuria in the concentrated early morning urine was examined. Protein concentration and dipstick readings were determined in early morning and daytime urines of 56 normal subjects and 110 patients with proteinuria attending a renal clinic. In normal subjects the protein concentration was similar in both urine samples and dipsticks gave the same frequency of false positive results, usually only trace positive. The protein concentration was higher in the daytime urine in 76% of patients. Dipstick readings were similar in 64.5% but higher in the daytime urine in 31% and in the early morning urine in only 4.5%. It is recommended that daytime urine should be screened for proteinuria in patients presenting in out-patient clinics.

False Positive Reactions

Biological equivalence of natural bovine and recombinant human alpha-endothelial cell growth factors.

The cDNA encoding human alpha-endothelial cell growth factor (alpha-ECGF) has been engineered for high-level expression in Escherichia coli. Induction of bacterial cultures harboring the recombinant plasmid pMJ26 results in the appearance of a prominent 16-kDa polypeptide. This protein has been purified from bacterial lysates using a rapid, 2-step procedure employing heparin-Sepharose affinity based chromatography and reversed-phase high pressure liquid chromatography. Recombinant human alpha-ECGF was compared to bovine brain-derived alpha-ECGF in three biological assays: receptor binding on murine lung capillary endothelial cells (LE-II cells), stimulation of [3H]thymidine incorporation in LE-II cells, and stimulation of human umbilical vein endothelial cell proliferation. The results demonstrate that the recombinant human mitogen has the same biological potency as the bovine brain-derived material. Fluorescence spectroscopy was used to study the interaction between recombinant ECGF and heparin. Heparin-binding resulted in a 40% reduction in the intrinsic fluorescence of ECGF, consistent with a heparin-induced conformational change. The intrinsic fluorescence of ECGF also varied as a function of pH.

Amino Acids

Delayed onset of polymyalgia in polymyalgia rheumatica.

Four female patients presenting with systemic symptoms of polymyalgia rheumatica are described. They suddenly developed classical girdle pains up to a year after the onset of severe systemic symptoms, a course not often emphasized.

Aged

Protein creatinine index and Albustix in assessment of proteinuria.

The protein creatinine index in early morning and random urine specimens was compared with the 24 hour urinary excretion of protein in normal subjects and outpatients with abnormal proteinuria. A protein creatinine index (defined as (mg protein/1 divided by creatinine mmol/1) times 10) below 125 in a random specimen excluded abnormal proteinuria, whereas an index of more than 136 indicated the presence of pathological proteinuria. The index for random specimens provided a useful semiquantitative assessment of the 24 hour excretion of protein (mg protein/24 hours), but the index for early morning specimens was less reliable. Errors with Albustix were partly due to intra and inter observer variations in the interpretation of the colour formed when compared with the chart provided. It is proposed that the protein creatinine index on random urine samples should be used to supplement dipsticks in screening for proteinuria in cases where misclassification would be serious.

Creatine