Search PubMed⌕ Search

Biomedical subjects

P Mills

Publications and source records attributed to P Mills.

At least 91 records · Page 5Linked to original sources
PubMed1990

Ultrasound in the diagnosis of granulomatous liver disease.

Ultrasound is a widely used method of assessing the liver for space occupying lesions and, more recently, parenchymal liver disease. We have reviewed the ultrasound scans and reports of 11 patients with biopsy proven granulomatous liver disease. Multiple echogenic lesions 3-5 mm in diameter, each surrounded by an hypoechoic halo, were seen in the liver of all the patients and in the spleens of three patients. A specific diagnosis of granulomatous hepatitis was suggested at the time of scanning in seven patients. An abnormal liver was noted in the other four patients but no specific diagnosis was suggested. We believe that granulomata in the liver can be detected using ultrasound and, if the above appearances are seen during an ultrasound scan, a diagnosis of granulomatous hepatitis should be considered.

Adult↗
PubMed1990

Prediction of salt sensitivity.

The overall prevalence of salt sensitivity was studied in 75 men stratified by diagnosis (hypertensive v normotensive) and race (black v white). All were studied in a crossover design employing a 200 mEq and 10 mEq Na/day. High salt led to a decrease in diastolic pressure for all groups (P less than .002). For systolic pressure, there was no salt effect on blood pressure across the whole group; however amongst the hypertensives, particularly the black hypertensives, high salt led to increases in systolic pressure (P less than .022). Obese patients were more likely to increase their systolic pressure in response to salt loading (P less than .05). The patients whose pressure increased on high salt were those who manifested less of a decrease in plasma levels of norepinephrine and renin in response to salt loading (both P less than .05). Systolic salt sensitivity was predicted with high statistical power (R = 0.689, P less than .00001) by a multiple regression equation employing: race; diagnosis; the change in renin and norepinephrine levels with diet; and the change in BP sensitivity to infused norepinephrine across the two diets. In view of the findings of increased norepinephrine, renin and diastolic pressure on low salt and in view of the particular physiological and epidemiological setting associated with systolic salt sensitivity, one wonders about the advisability of across-the-board recommendations of low salt diets for all hypertensive patients.

Adult↗
PubMed1990

Identification of a high risk subgroup of patients with silent ischaemia after myocardial infarction: a group for early therapeutic revascularisation?

Asymptomatic ("silent") ischaemia has been shown to be of prognostic significance in patients with stable and unstable angina and more recently in patients recovering after myocardial infarction. No therapeutic regimen has yet been shown to improve the prognosis of patients with silent ischaemia after infarction, which can be found in as many as a third of these patients. Attempts to achieve therapeutic revascularisation in all these patients may be undesirable, but early revascularisation could be especially beneficial in some selected high risk patients. Two hundred and fifty consecutive clinically stable survivors of myocardial infarction who had predischarge submaximal exercise tests were followed up for a year. Silent ischaemia was found in 27% of these patients; 15% had symptomatic ischaemia. Patients with a positive exercise test were prescribed a beta blocker before discharge. Mortality in patients with silent (9.4%) and symptomatic (5.4%) ischaemia in the first year after infarction was not significantly different. Patients with symptomatic ischaemia were more likely to have undergone coronary artery bypass grafting in the first year. Patients with silent ischaemia were, however, significantly more likely to die than patients with a negative exercise test (relative odds 12:1). Patients with silent ischaemia and an abnormal blood pressure response or who could not complete a submaximal exercise protocol were at particularly high risk, being 32 times more likely to die than those with a negative test (95% confidence interval from 3.3 to 307 times more likely). First year mortality in this group was 22%. The benefits of therapeutic revascularisation in this high risk group need to be studied.

Coronary Angiography↗
PubMed1990

Effects of salt, race, and hypertension on reactivity to stressors.

Blood pressure and heart rate reactivity to a psychological stressor and to a cold pressor test were examined in a group of 51 normotensive and 37 unmedicated hypertensive men. All were studied twice, once while the participants were maintained on a moderately high salt (200 meq sodium/day) diet and once while the participants were maintained on an extremely low salt (10 meq sodium/day) diet. Dietary salt had no effect on blood pressure or heart rate responses to the two stressors. The systolic and diastolic responses of the white participants to the psychological stressor were greater than those of the black participants (both p less than 0.05); however, there was no difference between blacks and whites in reactivity to the cold pressor challenge. As compared with the normotensive group, the hypertensive group reacted to the psychological stressor with increased responses in systolic blood pressure, diastolic blood pressure, and heart rate (all p less than 0.05). The hypertensive group also hyperresponded in terms of the systolic pressure response to the cold pressor task (p less than 0.05). Plasma norepinephrine and epinephrine responses were not significantly different across the two diets, races, or diagnoses.

Adult↗
PubMed1990

Beta-adrenergic receptor sensitivity during sodium restriction and converting enzyme inhibition.

Adding converting-enzyme inhibitors to the salt depleted state is marked by a reduction in blood pressure despite compensatory increases in heart rate and plasma norepinephrine. This study investigated whether this increase in sympathetic function is also accompanied by an increase in beta-adrenergic receptor function. Ten subjects were studied following two separate five day hospitalizations on 10 mEq sodium diets while receiving either placebo or captopril. During low sodium with captopril, blood pressure and angiotensin II decreased, while heart rate, renin, norepinephrine and isoproterenol-stimulated cyclic AMP accumulation in lymphocytes increased. The results indicate that enhanced beta-adrenergic receptor function does accompany sympathetic activation during sodium restriction and converting enzyme inhibition and further support studies showing that the renin-angiotensin system plays the dominant role in blood pressure regulation in the sodium depleted state.

Adult↗
PubMed1990

Renin correlates with blood pressure reactivity to stressors.

This study examines the relationship between renin levels and physiologic reactivity to stressors. Seventy-five normotensive and mildly hypertensive men were studied on a high salt diet (200 mEq/day Na) and on a low salt diet (10 mEq/day Na). Renin, plasma catecholamines, heart rate, and blood pressure were examined at rest, after standing in place for 8 minutes, and after a brief mathematics task. Renin levels increased in response to the stressor tasks, particularly on the low salt diet. The change in diastolic pressure in response to the stressor tasks was correlated with the change in renin (r = 0.45, p less than 0.001) but not with the change in norepinephrine. The combination of change in renin and norepinephrine levels accounted for 21% of the variance in predicting diastolic pressure reactivity (p less than 0.0015).

Adult↗
PubMed1989

Use of telemetry to record body temperature and activity in mice.

A complete, commercially available, integrated telemetry and data acquisition system is described, which is used to record core temperature and activity in mice. The system is comprised of a telemetry transmitter (implanted in the peritoneal cavity), a receiver (placed underneath the cage) connected to a computer with software (Dataquest), which converts the transmitter signals directly into core temperature and activity. The information is stored on either a floppy diskette or a hard disk in the computer. The effects of anesthesia (sodium pentobarbital, halothane), handling, aggregation, restraint, a cholinergic agonist (oxotremorine), and an anticholinesterase agent, soman (pinacolyl methylphosphonofluoridate), on core temperature and activity were examined. The telemetry system for the recording of core temperature and activity provides a more accurate assessment of the temporal effects of various drugs and is more efficient and less labor intensive than the use of a rectal temperature probe.

Animals↗
PubMed1989

Does chromogranin a respond to short-term mild physiologic challenge?

Plasma chromogranin A, norepinephrine, epinephrine, blood pressure, and heart rate were examined in 51 unmedicated volunteers at rest, in response to postural stimulation, and in response to a mild behavioral stressor. The short-term stressors led to the expected increases in catecholamines, blood pressure, and heart rate; however, chromogranin A was not influenced by these stimuli. Chromogranin A levels were not higher in the hypertensives, nor were they correlated with any of the other physiological variables. Although chromogranin A is coreleased with catecholamines from the sympathoadrenomedullary system, it does not respond to modest short-term postural or psychological stimuli that simultaneously evoke changes in other variables relevant to the sympathetic nervous system.

Adult↗
PubMed1989

Doppler colour flow mapping: technology in search of an application?

Although Doppler colour flow mapping may considerably reduce the need for conventional pulsed Doppler examination, quantitative flow measurements (particularly by continuous wave Doppler) are still essential in the evaluation of many conditions such as aortic stenosis. Doppler colour flow mapping is an important addition to the accurate non-invasive evaluation of several haemodynamic disorders of the heart and, as the technology improves, the range of applications will undoubtedly increase. Any technique that provides additional diagnostic information, makes an examination easier and quicker to perform, and at the same time provides data in a more comprehensible format has surely found a niche.

Color↗
PubMed1989

Total abdominal and pelvic ultrasound: incidental findings and a comparison between outpatient and general practice referrals in 1000 cases.

Ultrasound examination is a rapid and non-invasive method of examining the abdomen. Opinions differ as to whether the entire abdomen and pelvis should be examined in all cases or whether examination can be confined to the region of suspected pathology. The aim of this study was to evaluate the diagnostic yield of total abdominal and pelvic ultrasound examination in patients referred for primary diagnostic ultrasound and with particular reference to specific symptoms. The results of 1000 examinations were analysed. In 25% of patients, a significant abnormality was found and almost one-third of these were incidental findings. The incidence of abnormalities was not significantly different between patients referred via their general practitioners and those referred via the hospital outpatients department. We recommend total abdominal and pelvic examination in all cases regardless of the presenting symptoms.

Abdomen↗
PubMed1989

Lymphocyte basal cyclic AMP production predicts blood pressure.

Cyclic AMP (cAMP) serves as the second messenger for a variety of receptor systems. While much attention has been placed on the importance of receptor-stimulated levels of cAMP accumulation, little attention has been given to the potential importance of the unstimulated basal levels. We measured both stimulated and unstimulated cAMP accumulation, as well as receptor number, in lymphocytes in 15 subjects and found relatively strong associations between basal cAMP accumulation and systolic (p = .004) and diastolic (p less than .001) blood pressure. Blood pressure was unrelated to either receptor number or adrenergically-stimulated levels of cAMP. These results underscore not only the complexity of the role of cAMP in the regulation of blood pressure but also the usefulness of peripheral blood cells as models of more central physiological regulation.

Adult↗
PubMed1988

In vivo and in vitro 31P-NMR preliminary studies of the VX-2 carcinoma in rabbits.

In vivo and in vitro 31P-NMR spectroscopy was used to study the high energy phosphate metabolism of VX-2 tumors implanted into rabbit liver, kidney, and hind-limb muscle. Tumors, at various stages of growth, were first examined by in vivo 31P-NMR spectroscopy, then they were excised and underwent histologic examination and biochemical analysis; both in vitro 31P-NMR and standard enzymatic techniques were used. There was good correlation among the in vivo NMR spectra, the in vitro NMR data, and the biochemical analyses. Although the tumor spectra showed characteristics similar to those reported in the other tumor models, there was a striking variability in the spectra obtained from tumors implanted in the same site and from different sites. There was poor correlation between the degree of necrosis in the tumor and the tumor pH and between the Pi:ATP ratio and necrosis. This variability has important implications for the potential value of using 31P-NMR spectroscopy to monitor tumor growth and therapy in vivo.

Adenosine Triphosphate↗