Search PubMed⌕ Search

Biomedical subjects

J M Potter

Publications and source records attributed to J M Potter.

At least 55 records · Page 3Linked to original sources
PubMed1991

Intravenous regional administration of methylprednisolone in rheumatoid arthritis.

Intravenous regional administration of corticosteroid (IVRAS) in the treatment of rheumatoid arthritis of the hand has not been reported previously. The method is based on a modification of Bier's block, with substitution of corticosteroid for local anaesthetic. Twenty-two patients were assessed in this double-blind, placebo-controlled study. The technique was safe and effective in improving grip strength, with a group mean improvement of more than 50%. Because suppression of endogenous cortisol production 24 h after treatment was commensurate with the dose of methylprednisolone used (40 mg), we could not exclude that the response may have been due to systemic steroid. Further studies are required to define the real value of IVRAS as it may offer alternative treatment of the joints and tendons within the hand and wrist in some patients rather than more prolonged oral therapy or individual, multiple joint or sheath injections.

Arthritis, Rheumatoid↗
PubMed1991

Lactose in blood in nonpregnant, pregnant, and lactating women.

Lactose synthesized in the mammary gland can pass into the bloodstream by either a paracellular or transcellular pathway. In nonpregnant, nonlactating women, the concentration of lactose in the blood plasma was 1.5 +/- 0.1 microM (mean +/- SEM) in 9 women and undetectable in another 11 women. During pregnancy, this concentration was 3.7 +/- 0.4 microM at 10-21 weeks of gestation, with an increase to 8.7 +/- 1.8 microM by 38-40 weeks of gestation. At the initiation of lactation, the concentration of lactose peaked 3-5 days after birth, with a mean peak concentration of 75 +/- 18 microM, and then decreased to 30 +/- 8 microM when lactation was well established at 6 weeks after birth. These findings suggest that the mammary glands are synthetically active by the beginning of the second trimester of pregnancy and reach maximum synthetic capacity soon after birth. Measurement of concentrations of lactose in the blood plasma during pregnancy and lactation may allow an assessment of the successful initiation of both lactogenesis I and II.

Female↗
PubMed1990

Mortality associated with ischaemic hepatitis.

Twenty-nine patients of 18,000 inpatient admissions over a six-month period developed ischaemic hepatitis accompanied by peak aspartate aminotransferase (AST-EC 2.6.1.1) activity greater than 1,000 U/L. Seventeen of these 29 patients died either during or shortly after the episode of ischaemic hepatitis, with an overall mortality of 58.6%. Mortality was not due in any of the cases to the hepatitis but rather the underlying cause. Ischaemic hepatitis was the commonest cause of an AST activity greater than 1,000 U/L in this hospital population (29 of 52 patients i.e. 56%). This condition is more common than generally appreciated and is associated with a poor prognosis.

Aspartate Aminotransferases↗
PubMed1990

Comparison of tolbutamide and metformin in elderly diabetic patients.

In a randomized double-blind cross-over study the efficacy, metabolic effects, and acceptability of metformin were compared with tolbutamide in 20 diabetic patients aged between 65 and 95 years. No significant differences were noted after treatment in blood glucose control (fasting plasma glucose, metformin 9.1 +/- 2.8 mmol l-1, tolbutamide 8.3 +/- 2.8 mmol l-1; mean change, metformin +1.1 mmol l-1, tolbutamide +0.02 mmol l-1, p = 0.215), domiciliary blood glucose control, fasting insulin, lactate, cholesterol or triglyceride levels. There was a significant difference in weight change between the two treatments (on metformin -2.0 kg, from 63.2 +/- 11.8 to 61.2 +/- 12.3; on tolbutamide, +1.6 kg, from 61.4 +/- 11.1 to 63.0 +/- 12.3; p = 0.001). Initial gastro-intestinal side-effects occurred in 30% of patients with metformin. These were transient and responded to temporary reduction in treatment dosage. Metformin could not be distinguished from tolbutamide in elderly diabetic patients, except in that it was associated with weight loss.

Aged↗
PubMed1990

Effect on a geriatric service of opening a 25-bed ward on the district general hospital site: an audit.

Notes and discharge summaries of 2,560 patients were analysed in a pre-planned study to determine how the establishment of a 25-bed assessment ward on the district general hospital (DGH) site affected the work of a geriatric unit that had previously had no DGH beds. Throughput, changes in referrals and practice, and changes in outcome were measured using a computerised programme which examined the work of the unit for a year before and a year after the opening of the assessment ward. There were no changes in overall bed numbers or staffing, so changes were likely to be the direct result of establishing the DGH beds. The second year of the study showed a 33% increased throughput, with increased referrals from the accident and emergency department and evidence of more active investigation and treatment and a tendency towards a shorter length of stay. There was an increased number of transfers from all departments to the geriatric department for rehabilitation and a shortened time interval to transfer. Admissions to the general medical unit for patients aged 65-74 and 75+ did not change.

England↗
PubMed1989

Myoclonus associated with treatment with high doses of morphine: the role of supplemental drugs.

OBJECTIVE: To estimate the prevalence of important side effects in patients with malignant disease who were receiving high doses of morphine as part of their palliative treatment. DESIGN: Data on patients were collected over 12 months. SETTING: Two palliative care units in Western Australia. PATIENTS: 19 Patients with malignant disease who were receiving morphine either subcutaneously or orally as the main analgesic. 10 Patients receiving a total daily dose of morphine of at least 500 mg orally or 250 mg parenterally were enrolled in the study. The other 9 patients were enrolled after an important problem thought to be related to the morphine had been identified. All of the patients were taking drugs to supplement the treatment. INTERVENTIONS: The dose of morphine or route of administration, or both, was changed in three patients. MAIN OUTCOME MEASURE: Determination of the prevalence of side effects in the patients. Assessment of the relation of any side effects with the supplemental drugs taken by the patients. MAIN RESULTS: Plasma morphine and electrolyte concentrations were measured and a full history taken for each patient. Thirteen of the 19 patients had an important side effect; 12 of them had myoclonus and one had hyperalgesia of the skin. Plasma morphine concentrations were similar in patients with and without myoclonus, ranging from 158 to 3465 nmol/l and 39 to 2821 nmol/l respectively. Eight of the patients with side effects were taking an antipsychotic drug concurrently compared with none of those without side effects. A greater proportion of patients with side effects were taking the antinauseant drug thiethylperazine (6/13 v 2/6) and at least one non-steroidal anti-inflammatory drug (10/13 v 2/6), whereas a smaller proportion were taking a glucocorticosteroid (3/13 v 4/6). The estimated prevalence of important side effects in the total population of patients receiving palliative treatment in the two units was 2.7-3.6%. CONCLUSIONS: Myoclonus as a side effect of treatment with morphine is more likely to occur in patients taking antidepressant or antipsychotic drugs as antiemetics or as adjuvant agents or non-steroidal anti-inflammatory drugs for additional analgesia. If a patient develops myoclonus the best approach may be to change the supplemental treatment.

Adult↗
PubMed1988

Hormone binding globulins undergo serpin conformational change in inflammation.

A surprising recent finding is that thyroxine binding globulin (TBG) and cortisol binding globulin (CBG), are members of the serine protease inhibitor (serpin) superfamily. Apparently evolution has completely adapted the serpin structure for its new role in these proteins as a transport agent, as there is no evidence of any retained protease inhibitory activity. This drastic change in function raises the question as to why such a complex molecular framework has been selected for the relatively simple task of hormone transport? To function as inhibitors the serpins have a native stressed (S) conformation that makes them vulnerable to proteolytic cleavage, the cleavage being accompanied by an irreversible transition to a stable relaxed (R) form. We demonstrate here that TBG and CBG have retained the stressed native structure typical of the inhibitor members of the family and we provide evidence that the S-R transition has been adapted to allow altered hormone delivery at inflammatory sites.

Amino Acid Sequence↗
PubMed1987

Corticosteroid binding globulin in normotensive and hypertensive human pregnancy.

Corticosteroid binding globulin (CBG) concentrations in maternal plasma have been measured throughout pregnancy in a series of 100 singleton pregnancies in 89 normotensive women. Plasma CBG concentrations were monitored also in 10 women with essential or renovascular hypertension. Plasma albumin, cortisol and oestriol were measured concurrently. Plasma CBG increased two and a half to three times during pregnancy. In those women who developed hypertension in pregnancy (mean arterial pressure greater than 107 mmHg), the plasma CBG concentrations were significantly lower than in those who remained normotensive. In women who developed hypertension, the CBG either failed to increase at the same rate as in normal pregnancies or the level fell before the appearance of hypertension. The earlier the onset of hypertension, the greater the decline in CBG. In all subjects, the CBG concentration at 34-36 weeks gestation was directly related to the birthweight of the infant. Plasma cortisol levels were depressed in hypertension relative to that in the normotensive women. Whilst plasma albumin levels decreased at least 30% in most women during pregnancy, the fall tended to be less in hypertensive women, but there was marked overlap between patient groups. Plasma oestriol concentrations were depressed only in the very severely affected cases. It is suggested the CBG concentration is a further reflection of the metabolic abnormalities associated with hypertension in pregnancy, and that it can be used as a marker to identify and monitor those patients at risk.

Adult↗
PubMed1987

Interleukin 2 synthesis in the presence of steroids: a model of steroid resistance.

In this study interleukin 2 (IL-2) synthesis by human lymphocytes in the presence and absence of prednisolone in a group of normal subjects has been assessed. An association between suppression in vitro of induced phytohaemagglutinin-blastogenesis by prednisolone and synthesis of IL-2 was found. Those subjects whose lymphocytes are identified as steroid-resistant have significantly higher IL-2 activity in the supernatants of both steroid and non-steroid treated lymphocyte cultures than steroid sensitive subjects. The addition of exogenous IL-2 was found to ablate the suppressive effects of steroids on lymphocyte blastogenesis. These results suggest that significantly greater activity of IL-2 in the culture supernatants of steroid resistant subjects may represent a mechanism for glucocorticoid resistance in vitro and help explain the relationship between increased loss of grafts and steroid resistance in renal allograft recipients.

Adult↗
PubMed1986

Evaluation of nonpalpable breast lesions. Experience in a training institution.

Biopsy directed by needle localization is a safe and relatively simple method of obtaining abnormal tissue for histologic examination without sacrificing surrounding normal breast tissue. In the setting of a training institution, accurate results can be expected as technical skills are obtained by a variety of housestaff. In this series of 70 biopsies, the lesion targeted on mammography was removed on the initial attempt in all but 1 instance, for an overall accuracy of 99 percent.

Adenofibroma↗
PubMed1986

Amino acid profiles in early diabetic and non-diabetic pregnancy.

Plasma amino acid concentrations were measured in six insulin-dependent diabetic women and seven non-diabetic women in early pregnancy while fasting and one hour after a standard meal. Fasting plasma levels of total amino acids and individual amino acids were similar in the two groups, excepting isoleucine, which was raised in the diabetics. One hour post-prandially total amino acid concentrations were similar in the two groups; however, mean concentrations of total branched chain amino acids and mean concentration of the individual amino acids, serine, valine, isoleucine, leucine and tyrosine were elevated in the diabetics. Amino acids are important in early islet development and in insulin secretion from fetal pancreas in vitro. The elevated post-prandial amino acid levels found in pregnant diabetics in early pregnancy may contribute to fetal islet hypertrophy and hyperinsulinaemia.

Adult↗
PubMed1986

The effect of intra-articular steroids on plasma salicylate concentrations.

Plasma salicylate concentrations and salicylate clearances were evaluated in 10 patients before and then 3 days after the intra-articular administration of glucocorticoid steroids. All patients were on chronic salicylate treatment, the dosage varying from 1.3-4.6 g day-1 of enteric-coated aspirin. The mean steady state plasma concentration (+/- s.e. mean) of salicylate decreased significantly after intra-articular steroid (90.9 +/- 14.8 mg l-1-64.7 +/- 8.9, P less than 0.05), whilst the mean clearance increased significantly (87.3 +/- 20.6 ml min-1-120.6 +/- 28.3, P less than 0.05). In these paired studies, the intra-articular administration of steroids lead to a significant decrease in plasma salicylate levels in patients taking enteric-coated aspirin.

Administration, Oral↗
PubMed1985

Glycosylated haemoglobin in normal pregnancy: a longitudinal study with two independent methods.

Twenty-one women completed a longitudinal study of glycosylated haemoglobin in normal pregnancy. Glycosylated haemoglobin levels were measured using two independent techniques (ion-exchange column and colorimetric). Concurrent serial oral glucose tolerance tests (75-g glucose load) and erythrocyte indices were obtained. Changes in mean glycosylated haemoglobin were similar with both techniques with a nadir at 17 weeks, a peak at delivery (p less than 0.002 versus 17 weeks) and a fall post-partum. Glycosylated haemoglobin levels in abnormal pregnancies, e.g. diabetic, should be interpreted in the knowledge of these physiological changes.

Adolescent↗