PubMed Health⌕ Search

Biomedical subjects

R P Hullin

Publications and source records attributed to R P Hullin.

At least 19 recordsLinked to original sources
PubMed1989

Is severe wasting in elderly mental patients caused by an excessive energy requirement?

Many chronically ill mental patients show rapid and severe weight loss leading to severe nutritional debilitation. Excessive energy requirements secondary to hypermetabolism or hyperactivity have been proposed as the cause. This hypothesis was tested using the new doubly-labelled water (2H218O) technique to obtain accurate estimates of total energy expenditure (TEE) in 14 such patients. Mean TEE was very low (6.1 +/- 1.3 MJ/day). None of the subjects was in significant negative energy balance when studied. Mean resting metabolic rate (RMR) was lower than predicted from standard equations based on healthy elderly subjects. The energy cost of physical activity plus thermogenesis was also low (1.7 +/- 0.9 MJ/day) in all except one subject. The data refute the initial hypothesis and suggest that negative energy balance may be episodic, perhaps during periods of infection and subsequent recovery.

Aged↗
PubMed1988

Antidepressive effect of amitriptyline treatment with plasma drug levels controlled within three different ranges.

Seventy-four depressed patients were treated with amitriptyline for 4-6 weeks. Their doses were individually adjusted to maintain the sum of the plasma levels of amitriptyline (AT) and nortriptyline (NT) within one of three different ranges, randomly allocated. Allowance was made for individual plasma binding of the drugs. In the 50 patients between 25 and 65 years of age, the antidepressive response at low plasma drug levels was somewhat poorer than at medium or high levels, which were equally effective. In this age group an association was found between outcome and the individual rate of AT metabolism, expressed as "reciprocal clearance" (RC), the steady-state plasma concentration of AT plus NT divided by the daily AT dose. Good antidepressive outcome was associated with high RC. The implications of these findings for patient treatment and for the interpretation of other studies are discussed. The 18 patients between 65 and 80 years of age showed no significant differences between the effectiveness of treatment at different plasma drug levels, and no significant associations between outcome and RC.

Aged↗
PubMed1987

Arginine vasopressin in manic-depressive psychosis.

Urinary excretions of arginine vasopressin (AVP), sodium, potassium, osmoles and creatinine were measured in three in-patients with bipolar manic-depressive psychosis on at least eight 24-hour periods in each affective phase. Mood and body weight were recorded twice daily. The excretion by each patient of sodium, water and osmoles was greater in mania than during depression. Comparison of electrolytes and osmoles suggested that the increase was due to increased intake of salt and water rather than of total diet. There was a fall of mean AVP excretion during mania, the magnitude of the fall being related to the increase of water throughput. Compared with controls, AVP excretion was high and variable. It did not show the normal relationship to urine osmolality. Days with very high AVP were not associated with any characteristic feature of the other measurements; nor were they confined to any one point in the manic-depressive cycle. AVP does not appear to play a major role in the salt and water changes characteristic of manic-depressive psychosis and we have no evidence of its having any direct relationship to mood changes. We suggest that the observed abnormalities of AVP excretion are another manifestation of the central defect of this disease.

Arginine Vasopressin↗
PubMed1986

Abnormal indices of nutrition in the elderly: a study of different clinical groups.

Anthropometric and biochemical indices of nutrition were measured in 450 elderly women in six groups spanning a wide range of physical dependency. Data from the group of active subjects living at home was used to derive reference ranges for elderly women. Although the index values of this group did not differ greatly from those seen in young subjects, there were large differences between this and some of the other elderly groups where the frequency of low values was as high as 50% for some parameters. Food intakes were measured in four of the six groups and relationships were found between energy, protein and vitamin C intake and body weight, plasma protein levels and vitamin C concentration, respectively. Our findings suggest that, among elderly women, low levels of nutrient intake make a significant contribution to poor anthropometric and biochemical nutritional status. Improvements in diet should be reflected in the indices measured and might, in turn, have beneficial effects on health.

Adolescent↗
PubMed1985

Side-effects of lithium at lower therapeutic levels: the significance of thirst.

The prevalence of thirst, subjective polyuria and related side-effects was investigated in 87 patients attending a lithium clinic and in a group of 52 controls. Thirst was surprisingly common, occurring in 67% of patients, in spite of the fact that they had been maintained on relatively low levels of lithium, and was due principally to the lithium rather than to other psychotropic drugs. Urine flow and impaired renal water absorption correlated with the serum lithium level and the length of treatment in the patients, despite the fact that few were clinically polyuric. The pattern of the results confirms previous suggestions that lithium may stimulate the thirst mechanism directly as well as via an increased renal resistance to vasopressin. The possible implications in terms of clinical response are discussed.

Bipolar Disorder↗
PubMed1985

The cause and correction of low blood vitamin C concentrations in the elderly.

Chronically sick elderly women had low intakes and low blood concentrations of vitamin C. Small dietary supplements of vitamin C increased the concentration of vitamin C in their plasma and leucocytes to those found in both the active elderly and the young. These findings confirm that low concentrations of vitamin C in the institutionalized and chronically sick elderly are primarily due to poor intake and can be easily corrected by dietary changes. The case for increasing the intake of vitamin C in these patients is discussed.

Adult↗
PubMed1985

Nutritional state of elderly women on admission to mental hospital.

Since nutritional deficiencies might worsen the severity of symptoms and prolong the length of illness in non-nutritional disorders, particularly in the elderly, we examined the nutritional status of 216 elderly women newly admitted to a mental hospital. Compared to healthy elderly women, they had lower values for plasma prealbumin, vitamin C, and B vitamins. This was particularly common in senile dementia, and appeared to be the result of inadequate intake of protein or vitamins. Regular hospital diet for one month corrected the very low levels of prealbumin, but supplements were essential to remove deficiency of the water-soluble vitamins. Although vitamin supplements did not influence the length of stay in hospital, we did not exclude the possibility that nutritional deficiencies have a significant effect on the severity of mental illness.

Aged↗
PubMed1979

Renal function after long-term treatment with lithium.

Daily urine volumes, plasma creatinine concentrations, and creatinine clearance were measured in 106 patients with unipolar and bipolar affective disorders attending a "lithium" clinic. Urine volumes exceeded 3.51 in only six patients, plasma creatinine concentrations exceeded 150 mumol/1 (1.7 mg/100 ml) in only five, and creatinine clearance was below 50 ml/min in 16. Renal function was assessed by measuring creatinine clearance and renal tubular function, including response to 20 hours of water deprivation, in a representative sample of 30 patients from the lithium clinic and 30 psychiatric patients matched for age and sex who were taking other psychotropic drugs. Creatinine clearance and tubular function, including urine osmolality after water deprivation, were not significantly different between the two groups. Urinary excretion of arginine vasopressin (AVP), however, was much greater in the lithium-treated patients, who therefore had a diminished tubular responsiveness to AVP. The findings do not support suggestions that long-term lithium treatment results in seriously impaired renal function, renal damage, and polyuria. Compared with other series, however, the patients were being maintained with low serum lithium concentrations, which apparently area as effective prophylactically as higher concentrations.

Adult↗
PubMed1979

Rat-brain pyruvate kinase: purification and effects of lithium.

Purified pyruvate kinase was prepared from pooled brains obtained from untreated rats. Its properties suggest that it is similar to type 'M' pyruvate kinase. Lithium inhibition was demonstrated at pharmacologically significant lithium concentrations (7%-12% at 2 mmol 1-1 Li) and this was similar in character to that previously seen in rabbit muscle pyruvate kinase, namely noncompetitive with respect to phosphoenol pyruvate, K+, and Mg2+ but competitive with ADP.

Animals↗
PubMed1979

Erythrocyte electrolytes in recurrent affective disorders.

A modified method for determination of erythrocyte electrolytes is presented. The claims which have been made regarding the predictive value in periodic psychoses of erythrocyte electrolytes and 'lithium index' are questioned. Clinical experimental data of serial studies in patients receiving lithium suggests that theoretical predictions of distribution of lithium across erythrocyte membranes are not supported in practice and this lends support to the suggestion of active lithium transport in the red cell. A simple method is described of determining the attainment of 'stable state' in long term lithium treatment.

Affective Symptoms↗
PubMed1979

Inhibition of aldosterone production in adrenal cell suspensions by serum from patients with manic-depressive psychosis.

A method of preparing a suspension of cells of the zona glomerulosa from rat adrenal capsules treated with crude collagenase is described. The cells responded to ACTH, angiotensin II and serotonin by increased production of aldosterone. Pooled human sera or individual human sera (from healthy normal or non-psychiatric in-patients) to a final concentration of 30% had no effect on ACTH-stimulated production of aldosterone. Many serum samples from five patients with manic-depressive psychosis, however, caused a reduction in aldosterone production; 65% of those samples taken during depression, 44% of the samples taken during manic episodes and 23% of the samples taken when the mood was normal. Sera from manic-depressive patients also reduced the production of aldosterone caused by angiotensin II or serotonin. This effect of serum from manic-depressives in vitro may be related to the abnormalities of aldosterone control in such patients.

Adrenal Glands↗
PubMed1978

Lithium-6 stable isotope determination by atomic absorption spectroscopy and its application to pharmacokinetic studies in man.

No useful radioisotope of lithium exists to assist in the study of its biochemical pharmacology. A simple method has been developed for the determination of the stable isotope 6Li by atomic absorption spectroscopy (AAS). The technique is applicable in any laboratory equipped with simple AAS apparatus. Analysis of total lithium content (E) by flame emission spectroscopy is followed by separate determination (A6 and A7) of atomic absorption by the sample of the light emitted by separate hollow cathode lamps manufactured from the isotopes 6Li and 7Li. The standard curve of absorption ratio (A6/A7) against isotopic ratio (6Li/7Li) at any concentration (E) is an exponential which may be solved using a simple programmable calculator. Application of this method to the study of the pharmacokinetics of 6Li administered to 4 normal volunteers previously loaded with 7Li suggests that the rate of appearance of lithium in blood is unaffected by the previous state of lithium loading.

Humans↗