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Featured researches published by J. T. C. Ma.


Stroke | 1988

Hyperglycemia is a stress response in acute stroke.

E. Woo; J. T. C. Ma; J. D. Robinson; Y. L. Yu

To explore further the relation between admission glucose concentration and outcome in stroke, we measured glucose, fructosamine, and glycosylated hemoglobin concentrations on admission in 216 patients seen within 24 hours after the onset of their first stroke. Fructosamine concentration reflects the degree of glycemia in the preceding 4-6 weeks and glycosylated hemoglobin concentration reflects that in the preceding 3 months. Based on clinical, computed tomographic, and necropsy findings, strokes were classified as cortical infarction, lacunar infarction, or intracerebral hemorrhage. Analyses were done including and excluding 47 diabetic patients. No correlation between neurologic outcome as mortality and fructosamine or glycosylated hemoglobin concentration was found. Survival showed a significant correlation with admission glucose concentration only for patients with intracerebral hemorrhage. Our results suggest that hyperglycemia is unlikely to worsen the outcome of acute stroke and that hyperglycemia probably represents either a latent diabetic state or a stress response.


Clinical Endocrinology | 1985

Association of HLA antigens with thyrotoxic Graves' disease and periodic paralysis in Hong Kong Chinese.

B. R. Hawkins; J. T. C. Ma; K. S. L. Lam; Cho-Li Wang; R. T. T. Yeung

The HLA‐A and ‐B antigen distribution in 132 Hong Kong Chinese patients with Graves’ disease, including 24 with thyrotoxic periodic paralysis, was compared with that in 110 controls. The HLA‐DR antigen distribution in 68 patients was compared with that in 47 controls. The prevalence of Bw46 was significantly increased in patients with Graves’ disease and with periodic paralysis. The prevalence of DRw9 was also slightly increased but not at a statistically significant level. The high prevalence of Bw46 related to patients with early age at onset whereas patients with later age at onset had a significantly increased prevalence of HLA B5. It is suggested that Graves’ disease in Chinese is due to two HLA‐associated mechanisms in which early‐onset disease is associated with Bw46 and late‐onset disease with B5.


Clinical Endocrinology | 1987

LONG‐TERM TREATMENT OF HYPERPROLACTINAEMIA WITH BROMOCRIPTINE: EFFECT OF DRUG WITHDRAWAL

Cho-Li Wang; K. S. L. Lam; J. T. C. Ma; Tak Mao Chan; M. Y. Liu; R. T. T. Yeung

Fifty‐one patients with hyperprolactinaemia (23 with macroadenoma, 23 with microadenoma, and five with idiopathic hyperprolactinaemia) were treated with bromocriptine for 2‐12 years (4.9 ± 2.9 years, mean ± SD). During therapy, the serum PRL levels were suppressed into the normal range in all but five patients. In these five patients, despite the high circulating PRL, gonadal function returned to normal in three, while in the other two gonadotrophin reserve was impaired even before therapy. Gel chromatography showed that one of these patients had a high proportion of a large molecular weight form of PRL. Twenty‐four patients received bromocriptine as the sole method of treatment for over 2 years (3.4 ± 2.3 years). In five out of the 24 subjects (21 %), serum PRL remained normal with no clinical symptoms after prolonged drug withdrawal (1‐4 years). Twenty‐one patients received radiotherapy in conjunction with bromocriptine therapy. Of these 11 had prior surgery. After a follow‐up of 6.0 ± 3.0 years after radiotherapy, serum PRL remained within the normal range in 6 out of 21 subjects (29%), 1‐4 years after bromocriptine withdrawal. One of the patients had impaired GH response to insulin hypoglycaemia developing after radiotherapy. We conclude that prolonged bromocriptine treatment is an effective treatment for prolactinomas.


Diabetes Research and Clinical Practice | 1991

Prediction of persistent carbohydrate intolerance in patients with gestational diabetes.

K.S.L. Lam; Dominic F. H. Li; Ian J. Lauder; C.P. Lee; A. W. C. Kung; J. T. C. Ma

A 12-month prospective study was carried out in 120 Chinese patients with gestational diabetes who were found to have persistent carbohydrate intolerance at 6 weeks postpartum. The 75 g OGTT and WHO diagnostic criteria were employed for both antepartum and postpartum assessment. By 12 months, persistent carbohydrate intolerance was found in 13.3% of the patients only, 6 patients were diabetic while 10 had impaired glucose tolerance. Of those whose carbohydrate tolerance reverted to normal, 85% did so within the first 6 months. The clinical variables were analysed by multiple discriminant analysis using the logistic model. Five prognostic variables which were predictive of persistent carbohydrate intolerance at 12 months were identified. In order of decreasing predictive value, these included a high fasting glucose during pregnancy and at the first postnatal visit, a high antepartum 2 h blood glucose, the requirement of insulin during pregnancy, and a high postpartum 2 h blood glucose. Macrosomia, gestational age at diagnosis and a family history of diabetes were not predictive of persistent carbohydrate intolerance. Multiparity, maternal age and body mass index were of marginal significance only. The fitted logistic model provides a mechanism to estimate the probability of persistent carbohydrate intolerance. Such information will be helpful in patient counselling and in the efficient planning of postpartum medical follow-up.


Diabetes Research and Clinical Practice | 1991

High prevalence of undiagnosed diabetes among Chinese patients with ischaemic stroke.

K.S.L. Lam; J. T. C. Ma; E. Woo; Clk Lam; Y. L. Yu

We reviewed the prevalence of diabetes mellitus, hypertension and cigarette smoking in 176 Chinese patients with acute stroke, classified, on computed tomographic findings, as intracerebral haemorrhage or cerebral infarction. In all patients with no known history of diabetes, a 75 g OGTT was done 3-6 months after ictus and interpreted using WHO criteria. The overall prevalence of diabetes and impaired glucose tolerance (IGT) was 33.5% and 21.0%, respectively, with a higher prevalence being found in patients with cerebral infarction (P less than 0.05). Forty percent of those with diabetes were previously undiagnosed - all but 2 had ischaemic stroke. Compared to reported findings in the general population, an increased prevalence of hypertension, and possibly also cigarette smoking was found in patients with both stroke categories. On the other hand, significant hypercholesterolaemia was not found in patients of either category. In view of the high prevalence of undiagnosed diabetes among these stroke patients and the increased morbidity and mortality associated with diabetes mellitus, screening for diabetes is recommended especially in those with ischaemic stroke. If a fasting plasma glucose of greater than or equal to 6 mmol/l was used for the initial screening of undiagnosed diabetes in this group of patients, the sensitivity and specificity values would have been 78% and 94%, respectively. Whether this cut-off value can be cost-effectively employed for mass screening remains to be confirmed by studies involving larger numbers of stroke patients.


Contraception | 1987

Glucose and Lipid Metabolism with Triphasic Oral Contraceptives in Women with History of Gestational Diabetes

A. W. C. Kung; J. T. C. Ma; Vivian C. W. Wong; Dominic F. H. Li; Matthew Ng; Christina C.L. Wang; Karen S.L. Lam; Rosie T.T. Young; H. K. Ma

The glucose and lipid metabolism in a group of women with previous history of gestational diabetes were evaluated before and after 6 months treatment with a low-dose triphasic oral contraceptives pill (TP). This group was compared with a control group of women, also with history of gestational diabetes, using intrauterine devices (IUD). In the TP group, 26.7% of the women developed impaired glucose tolerance which reverted to normal in all but one after cessation of the TP. The IUD group showed no change in glucose tolerance. The integrated insulin response to a 75g OGTT in the TP group increased by 48.3% at 6 months compared with an increase of 23.4% for the same period in the IUD group. In the TP group there was a significant decrease in serum total cholesterol without changes in HDL-cholesterol and triglycerides level. We conclude that even low-dose triphasic oral contraceptive pills can cause glucose intolerance in women with previous gestational diabetes mellitus.


Neuroradiology | 1987

CT appearance in hypertensive encephalopathy

Y. L. Kwong; Y. L. Yu; K.S.L. Lam; E. Woo; J. T. C. Ma; C. Y. Huang

Four months prior to admission this 23-year-old secretary developed blurting of vision and dizziness. Blood pressure was 300/170 mm Hg. Blood counts, electrolytes, renal function and intravenous urography were normal. Urinary ca~echolamines and VMAs were persistently elevated. On admission for uncontrolled hypertension (200/160 mm Hg), she was drowsy and disorientated, with papilloedema, multiple retinal haemorrhages and exudates, and left heart hypertrophy, but no focal neurological deficits. She went into acute pulmonary oedema next day. Malignant hypertension secondary to phaeochromocytoma was diagnosed. CT brain scan (Fig.l), performed immediately after admission without contrast as this might provoke a surge of catecholamines, showed extensive low attenuation in the white matter of the cerebral hemispheres and cerebellum. There was compression of the ventricular system and obliteration of peripheral sulci. Blood pressure and pulmonary oedema responded to treatment. Her mental state became normal on day 10. CT (plain and contrast) repeated 3 weeks later showed significant resolution of swelling and low attenuation. CT 6 months later was normal.


Diabetes Research and Clinical Practice | 1988

An assessment of drug information sheets for diabetic patients: only active involvement by patients is helpful*

Cr Kumana; J. T. C. Ma; Annie Kung; Maybelle Kou; Ian J. Lauder

Insulin/sulphonylurea-treated diabetics attending a busy university diabetic clinic were studied to determine whether issuing drug information sheets and/or age influenced understanding and behaviour regarding their disease and its treatment, especially with respect to avoiding hypoglycaemia. Patients were each asked 10 basic questions (each correct answer scoring 1), stratified by age (20 were less than or equal to 45 years and 91 greater than 45 years). According to a single-blind randomised protocol, they were issued or not issued with drug information sheets (providing information to correctly answer all 10 questions). After 2-3 months, 107 (88 aged greater than 45 years) were retested and asked whether they recalled an information sheet, read it themselves or had it read to them. Whether or not patients received sheets, corresponding mean aggregate scores were very similar in both age groups and there was no correlation with age. Second test scores yielded clinically and statistically significant increments in both the sheet and no sheet groups, respective mean aggregate scores increasing from 4.48 to 5.80 and 5.14 to 6.27 (P less than 0.001). Among patients issued with sheets, 32 who recalled reading them achieved the greatest improvement in mean scores (4.53 to 6.16, P less than 0.001). Active interaction/communication (participation in first test, recall and reading of information sheet) had a favourable educational impact irrespective of age, but merely issuing drug information sheets had no benefit.


Clinical Endocrinology | 1987

Prevention of hypoglycaemia in a patient with pancreatic microadenomatosis by a long-acting somatostatin analogue SMS 201-995.

A. W. C. Kung; J. T. C. Ma; Cho-Li Wang; K. H. Fu; K. S. L. Lam; R. T. T. Yeung; J. Boey

Acute suppression of insulin secretion from pancreatic insulinomas by long‐acting somatostatin analogue SMS 201‐995 has been documented. We report the chronic use of the drug in a patient with persistent hypoglycaemia due to benign pancreatic microadenomatosis with satisfactory control of plasma glucose level and reduction of insulin production. There was no tachyphylaxis or untoward side‐effect noted during the 6‐month treatment period.


The Journal of Clinical Endocrinology and Metabolism | 1987

Early effects of cranial irradiation on hypothalamic-pituitary function

K. S. L. Lam; V. K. C. Tse; Cho-Li Wang; R. T. T. Yeung; J. T. C. Ma; J. H. C. Ho

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K. S. L. Lam

University of Hong Kong

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Cho-Li Wang

University of Hong Kong

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E. Woo

University of Hong Kong

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K.S.L. Lam

University of Hong Kong

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Y. L. Yu

University of Hong Kong

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Annie Kung

University of Hong Kong

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