Biomedical subjects

C J Bulpitt

Publications and source records attributed to C J Bulpitt.

At least 271 records · Page 15Linked to original sources

PubMed1976

The relationship between blood pressure and biochemical risk factors in a general population.

The relationship between blood pressure, ponderal index, sex, blood glucose, haemoglobin, serum uric acid, calcium cholesterol and creatinine, and albumin has been examined in 698 subjects aged between 44 and 49 years from the register of a group general practice. Sixty per cent of the variation in systolic pressure could be explained by statistically significant associations with diastolic pressure, sex, blood glucose, serum calcium, and cholesterol. The diastolic blood pressure (not corrected for systolic pressure) was significantly related only to ponderal index, haemoglobin in men, and cholesterol in women. Pulse pressure was also positively related to the risk factors blood glucose, serum cholesterol, and calcium. The possibility is discussed that one or more of these variables reduce aortic compliance and that the serum calcium contributes to this end. Diastolic, but not systolic pressure, had a prime association with relative weight, obesity being only basically associated with an increase in diastolic pressure.

Adult↗

PubMed1975

The retinal blood flow in diabetes.

Retinal blood flow was studied in 9 normal volunteers and 36 diabetic patients. The method used was based on the measurement of the mean transit time of flourescein in the superior temporal quandrant of the retina and on estimation of the vascular volume by measuring vessels diameters. The results showed that patients with mild or no retinopathy had significantly increased volume flow compared with normals, those with moderate retinopathy had a slight but not significant increase and those with severe retinopathy had blood flow similar to that found in normals. The mean transit time was reduced significantly in those with mild or no retinopathy, but was similar to normals in those with moderate and severe retinopathy. Following succesful pituitary ablation and photocoagulation retinal blood flow was reduced compared with pre-treatment studies.

Adult↗

PubMed1975

Pathogenesis of hypertensive retinopathy. An experimental study in the monkey.

Retinal changes in accelerated hypertension were studied in seventeen monkeys with experimental hypertension by means of ophthalmoscopy and colour and flourescence photography during life, and by injection and digest preparations and light and electron microscopy after the animals had been killed. Cotton-wool spots developed in all but three monkeys. The arteries became tortuous and dilated and the light reflex decreased in those animals that became hypertensive. The earliest abnormality was a development of many points of fluorescein leakage on terminal arterioles or small arteries. Such leaking points were always present in relation to cotton-wool spots but were not confined to such areas. Focal narrowing of arteries was not observed but arteriolar occlusion and retrograde filling of the distal segment was present in three animals. Superficial linear haemorrhages were noted in five animals. Light microscopy revealed cotton-wool spots which were identical to those observed in man with a collection of swollen axons containing densely staining pseudonuclei. Study of the arterioles by electron microscopy showed findings ranging from normality to extensive necrosis. Many precapillary arteries were constricted and some were virtually occluded. Degenerative changes were present in smooth muscle cells in the wall of many of the constricted arterioles. Many arteries also showed insudation into their wall of plasma which had seeped into the muscular coat displacing and sometimes entirely replacing the smooth muscle cells. Except for arterioles with advanced necrosis, there was no indication of how plasma insudation occurred. Two arterioles with extensive necrosis showed a break within the endothelial cell cytoplasm through which penetration of plasma proteins had probably occurred. The extravascular tissues showed collections of amorphous material, sone of it with the typical banded configuration of fibrin. The sequence of events proposed to explain these features is as follows: (1) The arterioles constrict as the pressure rises, most likely as a result of vascular autoregulation. This may head to occlusion of the precapillary arterioles and is associated with necrosis of vascular smooth muscle. (2) Dilatation then occurs with insudation of plasma into the unsupported wall through a damaged endothelium. This stage probably corresponds to the autoregulatory break-point and is evidenced clinically by focal leakage of fluorescein. (3) Progressive plasma insudation into the vessel wall with further muscle necrosis results in secondary occlusion and the typical picture of advanced fibrinoid necrosis.

Animals↗

PubMed1975

Intraocular pressure and systemic blood pressure in the elderly.

The intraocular and systemic blood pressure, height, weight, and haemoglobin were measured in 573 subjects over 60 years old from a general practice population. Intraocular pressure was positively and independently related to systemic blood pressure (P less than 0.0001) and obesity (P less than 0.01) as assessed by the ponderal index. Systolic pressure rather than diastolic or mean pressure was most closely correlated with intraocular pressure and it is suggested that the systolic head of pressure increases the filtrated fraction of aqueous humour to cause a small but sustained rise in intraocular pressure. It is also suggested that obesity may decrease the facility of aqueous outflow.

Aged↗

PubMed1975

Serum uric acid in hypertensive patients.

Both the average serum uric acid and annual increment were determined in 250 treated patients attending a hypertension clinic. The average serum uric acid was greater in men compared with women, in patients receiving a thiazide diuretic and in patients with a high average plasma urea. The mean annual increment in uric acid was close to zero (0.0017 mmol/litre per year) and was not related to sex, age, blood pressure control, diuretic therapy, or plasma urea. There was an unexplained positive association between annual increment and methyldopa therapy though this drug was not associated with a significantly high average serum uric acid. A table is presented giving the theoretical upper limits for average serum uric acid according to sex, plasma urea concentration, and whether or not a thiazide diuretic has been prescribed. It is hoped that this table will be of assistance in assessing the normality or otherwise of a high serum uric acid found in a hypertensive patient.

Adult↗

PubMed1974

Computer-based hypertension clinic records: a co-operative study.

A computer-based medical record system has been developed to help with research into hypertension and the management of patients with hypertension. Standard medical records are replaced by data collection forms and case notes printed by the computer. A computer-generated document for recording information at follow-up visits contains an up-to-date summary of the important clinical features with warnings of risk factors. A blood-pressure graph and a letter for the general practitioner are produced on request. The system has been used in three clinics for two years and is being tested in general practice. Information on 900 newly-referred patients has been recorded and at present data on 30 to 40 new patients and 160 follow-up visits are added each month.

Blood Pressure↗

PubMed1974