Identification of linear epitopes of the BPV-1 L1 protein recognized by sera of infected or immunized animals

Sera from cattle that had been inoculated with BPV-1 virions or with recombinant L1 proteins and serum from a rabbit that had been immunized with SDS-denatured virions were evaluated for their reactivity with 466 overlapping synthetic peptides corresponding to 95% of the BPV-1 L1 protein. The late serological response of cattle to both intact virions and recombinant L1 proteins exhibited a similar profile of reactivity with approximately 70% (7 of 10) of L1 antigenic sites. However, the L1 serological response of the rabbit to SDS-denatured virions exhibited a significant difference from bovine serum antibodies in the profile of epitopes recognized, including a relative lack of response to major bovine epitopes located between L1 amino acids (AAs) 300-400. Importantly, only the sera from animals inoculated/immunized with intact virions was capable of neutralizing BPV-1 infectivity of murine C127 cells, suggesting that nonlinear epitopes are important for papillomavirus neutralization.

Chiral separation of glycyrrhetinic acid by high-performance liquid chromatography

An HPLC separation of the 18 alpha and 18 beta diastereomers of glycyrrhetinic acid (GA) has been developed. The separation was achieved with a chiral column (Merck ChiraSpher, Darmstadt, Germany) and a methanol-water (65:35, v/v) mobile phase. The separation is excellent, having a resolution factor of 2.3. The HPLC method is efficient and accurate for the optical purity determination of 18 alpha- and 18 beta-GA samples. The run time is less than 30 min. Quantitation is linear with a lower detection limit of 0.2% for one isomer in the presence of the other. Addition of 0.2% acetic acid to the water in the mobile phase improved the ruggedness of the system without affecting the resolution of 18 alpha- and 18 beta-GA. This modification also allowed partial separation of 18 alpha- and 18 beta-glycyrrhizin, precursors of the GA isomers.

Taxol content in bark, wood, root, leaf, twig, and seedling from several Taxus species

Taxol content in various parts of several Taxus species have been determined. The weight percent ranged from 0.00003 to 0.069.

MediNet: Singapore's nationwide medical network

MediNet is Singapore's nationwide computer network for the medical and health care community. This paper presents the case for MediNet and discusses the five high-priority applications which would be implemented by 1993. These 5 pilot applications focus on the processing of claims in hospital bills, electronic procurement of medical and surgical supplies, the transmission of notifications to government agencies, a national patient master index and access to local and foreign databases. MediNet will be able to link the computer systems of all participants in the healthcare delivery system. These include the Ministry of Health, Central Provident Fund (CPF) Board, government, restructured and private hospitals and general practice clinics. By connecting their computers (personal computers, minicomputers and mainframes) to MediNet, these organisations will be able to communicate, exchange data and access common applications on the network.

Cardiovascular diseases in Chinese, Malays, and Indians in Singapore. II. Differences in risk factor levels

STUDY OBJECTIVE

The aim of the study was to examine cardiovascular risk factors to see how these might explain differences in cardiovascular disease mortality among Chinese, Malays, and Indians in the Republic of Singapore.

DESIGN

The study was a population based cross sectional survey. Stratified systematic sampling of census districts, reticulated units, and houses was used. The proportions of Malay and Indian households were increased to improve statistical efficiency, since about 75% of the population is Chinese.

SETTING

Subjects were recruited from all parts of the Republic of Singapore.

SUBJECTS

2143 subjects aged 18 to 69 years were recruited (representing 60.3% of persons approached). There were no differences in response rate between the sexes and ethnic groups.

MEASUREMENTS AND MAIN RESULTS

Data on cardiovascular risk factors were collected by questionnaire. Measurements were made of blood pressure, serum cholesterol, low and high density lipoprotein cholesterol, fasting triglycerides and plasma glucose. In males the age adjusted cigarette smoking rate was higher in Malays (53.3%) than in Chinese (37.4%) or Indians (44.5%). In both sexes, Malays had higher age adjusted mean systolic blood pressure: males 124.6 mm Hg v 121.2 mm Hg (Chinese) and 121.2 mm Hg (Indians); females 122.8 mm Hg v 117.3 mm Hg (Chinese) and 118.4 mm Hg (Indians). Serum cholesterol, low density lipoprotein cholesterol and triglyceride showed no ethnic differences. Mean high density lipoprotein cholesterol in males (age adjusted) was lower in Indians (0.69 mmol/litre) than in Chinese (0.87 mmol/litre) and Malays (0.82 mmol/litre); in females the mean value of 0.95 mmol/litre in Indians was lower than in Chinese (1.05 mmol/litre) and Malays (1.03 mmol/litre). Rank prevalence of diabetes for males was Indians (highest), Malays and then Chinese; for females it was Malays, Indians, Chinese.

CONCLUSIONS

The higher mortality from ischaemic heart disease found in Indians in Singapore cannot be explained by the major risk factors of cigarette smoking, blood pressure and serum cholesterol; lower high density lipoprotein cholesterol and higher rates of diabetes may be part of the explanation. The higher systolic blood pressures in Malays may explain their higher hypertensive disease mortality.

Serum bioactive and immunoreactive follicle-stimulating hormone levels and the response to clomiphene in healthy young and elderly men

Testicular function declines with normal aging, while serum immunoreactive LH and FSH levels increase. Since there are reports of an age-related decrease in the ratio of bioactivity to immunoreactivity (B/I ratio) for LH, we used a newly available bioassay for FSH to assess age-associated changes in the bioactivity and B/I ratio of FSH in man. Thirty-nine healthy men (23 young and 16 elderly) had single blood samples drawn. In addition, a subset of these men (12 young and 13 elderly) underwent frequent blood sampling for 24 h, both before and after 7 days of clomiphene citrate (CC) administration. Hourly blood samples from the 24-h sampling were pooled, and these, along with the single samples, were assayed for FSH by an in vitro bioassay system, using estrogen production by immature rat granulosa cells as the end point, and by RIA. Baseline single sample mean FSH, as measured by bioassay, was similar in young and elderly men [386 +/- 98 (+/- SEM) and 342 +/- 77 ng/mL, respectively]. Baseline mean FSH, measured by RIA, was significantly higher (P less than 0.001) in elderly men (234 +/- 31 ng/mL) than in young men (122 +/- 12 ng/mL). The baseline FSH B/I ratio based on single sampling was significantly lower (P less than 0.01) in elderly men (1.4 +/- 0.2) than in young men (2.7 +/- 0.3). In the men given CC and sampled for 24 h, mean bioactive FSH levels increased significantly in both the young (1180 +/- 282 ng/mL) and the elderly (992 +/- 227 ng/mL; P less than 0.01 for both values compared to baseline). Mean FSH by RIA also increased to similar levels in these young (217 +/- 34 ng/mL) and elderly (258 +/- 45 ng/mL) men. The FSH B/I ratio was 4.8 +/- 0.8 in young and 4.7 +/- 1.1 in elderly men after CC administration. We conclude that serum bioactive FSH levels are similar in elderly and young men, suggesting that the age-related decline in testicular function in man cannot be explained by a chronic deficiency in FSH stimulation; elderly men have a lower serum FSH B/I ratio than young men, which may reflect changes in the circulating form of FSH with aging; and administration of CC to young and elderly men increases both bioactive and immunoreactive serum FSH, implying preserved hypothalamic-pituitary responsiveness in the elderly.

Monitoring the menstrual cycle of humans and lowland gorillas based on urinary profiles of bioactive follicle-stimulating hormone and steroid metabolites

A sensitive and specific in vitro granulosa cell aromatase bioassay was adapted to measure bioactive FSH (bio-FSH) levels in urine samples. Urinary levels of bio-FSH, immunoreactive LH, estrone conjugates, and pregnanediol-3-glucuronide (PdG) were measured in first morning urine samples during the menstrual cycle in six cycling women and four lowland gorillas. The cycle length of women was relatively constant [28 +/- 1 (+/- SD) days], but varied from 28-38 days for lowland gorillas; the length of the luteal phases was relatively constant for both. All subjects had a midcycle LH peak and a luteal phase elevation in PdG. In addition, urinary estrogen excretion displayed a midcycle elevation that preceded the LH peak and a luteal phase increase similar to that of PdG. The bio-FSH levels in urine of cycling women, although at almost 100-fold higher concentrations, exhibited a pattern that closely resembled that of serum bio-FSH levels reported earlier, with an early follicular phase rise and a midcycle peak. Statistical analysis indicated a highly significant correlation (r = 0.90) between serum and urinary bio-FSH levels during the human menstrual cycle and in women in several hypo- and hypergonadotropic states, including oral contraceptive pill users, hypothalamic amenorrhea, premature ovarian failure, and postmenopause. Although a midcycle bio-FSH surge was also detected in lowland gorillas, two peaks of bio-FSH levels were consistently found during the follicular phase. The late follicular phase increase in bio-FSH levels was presumably involved in follicle selection and preceded the midcycle FSH peak by about 6 days, whereas the timing of the early follicular phase peak was variable, suggesting the involvement of complex regulatory mechanisms. These findings suggest that measurement of urinary bio-FSH levels in humans reflects serum bio-FSH in subjects in several physiological and pathological states. Studies of urinary bio-FSH levels in humans and nonhuman primates are useful in monitoring menstrual cycles, and the gorillas may be a model for understanding human reproductive cycles. The urinary granulosa cell aromatase bioassay should be useful for future assessment of bio-FSH levels in situations where serum measurements are impractical or in animal species for which specific FSH RIAs are not available.

Vasoactive intestinal peptide stimulates androgen biosynthesis by cultured neonatal testicular cells

Vasoactive intestinal peptide (VIP) was originally isolated from porcine duodenum and considered to be a gut hormone. Recent evidence indicates that it may also be involved in reproductive functions. In this study, a possible action of VIP on steroidogenesis by cultured testicular cells was investigated. Neonatal testicular cells were treated in vitro with hormones for 3 days and medium steroid or cAMP content was measured by radioimmunoassay. Treatment of cultured cells with VIP (10(-9) to 10(-6) M) increased the production of testosterone, progesterone, and pregnenolone in a dose-dependent fashion. Testosterone production in response to 10(-6) M VIP was about 5-10% of that maximally induced by LH. Addition of methyl-isobutyl-xanthine, a phosphodiesterase inhibitor, to the VIP-containing cultures significantly enhanced production of testosterone by 13-fold, of progesterone by 9-fold, and of pregnenolone by 2.5-fold as compared to treatment with VIP alone. Additional experiments also showed a dose-dependent stimulation of cAMP production by VIP. The VIP-related hormones PHM-27, secretin, and glucagon also stimulated progesterone and testosterone production with a potency order (PHM-27 greater than secretin greater than glucagon) consistent with that observed for other VIP receptor-mediated actions. A direct stimulatory effect of VIP on Leydig cells was indicated in studies on steroidogenesis by testicular cells separated on a metrizamide density gradient. In these studies, VIP stimulated androgen production in an LH-responsive subpopulation of testis cells but failed to affect steroid production in non-LH-responsive cells.(ABSTRACT TRUNCATED AT 250 WORDS)

The supply of both CDP-choline and diacylglycerol can regulate the rate of phosphatidylcholine synthesis in HeLa cells

The incorporation of [methyl-14C]CDP-choline into phosphatidylcholine was measured in HeLa cells permeabilized with 0.125 mg digitonin/mL. The rate of phosphatidylcholine formation was influenced by the concentration of CDP-choline in the medium. The CDP-choline:1,2-diacylglycerol cholinephosphotransferase in permeabilized cells showed a Km of 88 microM for CDP-choline. A similar Km value of 104 microM was found for cholinephosphotransferase in microsomes isolated from HeLa cells when assayed in the presence of 2.4 mM dioleoylglycerol. In the absence of added diacylglycerol, the Km for CDP-choline for the microsomal cholinephosphotransferase was only 38 microM. The incorporation of [methyl-14C]CDP-choline into phosphatidylcholine was stimulated by the supply of diacylglycerol in both HeLa cells and isolated microsomes. A 2.4 mM dioleoylglycerol suspension increased cholinephosphotransferase activity fourfold in microsomes. The digitonin-treated cells were impermeable to the dioleoylglycerol suspension. Incubation of permeabilized cells with 150 microM acyl-CoA and 0.8 mM glycero-3-phosphate tripled cellular diacylglycerol levels, causing a doubling in the rate of phosphatidylcholine synthesis. A similar incubation of microsomes with acyl-CoA stimulated phosphatidylcholine synthesis twofold. Furthermore, incubation of microsomes with [3H]diacylglycerol and [14C]CDP-choline showed that both of the substrates were incorporated into phosphatidylcholine at the same rate. This result suggests that the stimulatory effects on cholinephosphotransferase arise from increases in the availability of substrates rather than activation of the enzyme. These results suggest that both in the permeabilized cells and in isolated membranes, the biosynthesis of phosphatidylcholine can be limited by both CDP-choline and diacylglycerol.

Hormonal regulation of androgen biosynthesis by primary cultures of testis cells from neonatal rats

Enzymatically dispersed testis cells derived from 7-day-old male rats maintained their gonadotropin-stimulated testosterone production for 18 days in culture. Treatment with hCG or LH stimulated androgen production in a dose-dependent manner, with ED50 values of 0.030 +/- 0.007 and 1.0 +/- 0.4 ng/ml for hCG and LH, respectively. Concomitant treatment with a phosphodiesterase inhibitor further enhanced LH action. In contrast, treatment with FSH, GH, or PRL was without effect. Treatment with forskolin, cholera toxin, or 8-bromo-cAMP induced dose-dependent increases in testosterone biosynthesis; this was accompanied by stimulation of 3 beta-hydroxysteroid dehydrogenase activity after treatment with hCG, forskolin, or 8-bromo-cAMP. RIA measurement of different androgens in HPLC-fractionated medium revealed that the main androgen secreted by the neonatal testis cells was testosterone, with lower production of 5 alpha-androstane-3 alpha,17 beta-diol and negligible 5 alpha-dihydrotestosterone, androstenedione, and androsterone. Treatment with epidermal growth factor, GnRH, and arginine vasopressin (AVP) decreased hCG-induced testosterone biosynthesis. Since the inhibitory actions of GnRH and AVP were blocked by concomitant addition of specific hormone antagonists, their inhibitory actions were probably mediated by specific testis receptors. In contrast, treatment with several potent synthetic steroid hormone analogs [diethylstilbestrol (an estrogen), dexamethasone (a glucocorticoid), R5020 (a progestin; 17,21-dimethyl-19-nor-4,9-pregnadiene-3,20-dione), R1881 (an androgen; 17 beta-hydroxy-17 alpha-methyl-4,9,11-estratrien-3-one), or cyproterone acetate (an antiandrogen; 17 alpha-acetyloxy-6-chloro-1,2-dihydro-(1 beta,2 beta)3'-H-cyclopropa-(1,2) pregna-1,4,6-trien-3,20-dione)] did not affect testosterone biosynthesis in hCG-treated cells. These results demonstrate that testosterone production by neonatal testis cells is maintained by gonadotropins during prolonged culture; the ability of cAMP-generating drugs and a cAMP analog to mimic gonadotropin actions on testosterone biosynthesis and 3 beta-hydroxysteroid dehydrogenase activity suggests a mediatory role of cAMP in gonadotropin action; and AVP, epidermal growth factor, and GnRH, through their putative testis receptors, directly inhibit gonadotropin-stimulated testosterone synthesis, while various steroids (androgens, estrogens, progestins, and glucocorticoids) do not affect Leydig cell function in the neonatal testis. The present culture system offers a unique model for elucidating the hormonal control of Leydig cell androgen biosynthesis during neonatal development.

Combined team management of diabetes mellitus in pregnancy

225 women with diabetes in pregnancy were managed by a team of obstetricians, physicians (endocrinologists) and paediatricians from the National University of Singapore. A protocol of management was formulated and followed. The incidence of 1.1% or 1 in 90 pregnancies was found, with significantly higher incidence in Indians and lower in Malays. There were 37 established diabetics and 188 diagnosed during pregnancy. Of these (188), 74 were gestational diabetics. All the women were treated with Insulin and Diet or Diet alone. 177 (79%) were treated with Insulin and Diet. Blood sugar profiles were done for monitoring diabetic control. 72.8% of the women were between para 0 and 1 and 85.2% between the ages of 20 and 34. 72.5% of the women delivered at 38 weeks gestation or later. 48.9% went into spontaneous labour, 32.4% were induced and 18.7% had elective caesarean section. 62.2% of the women had labour of less than 12 hours. The overall caesarean section rate was 41.7%. There were 3 stillbirths and 2 neonatal deaths. The perinatal mortality rate was 2.2%. Thirteen babies had congenital malformations (5.8%). 77.8% of the babies had Apgar score of 7 or more at 5 minutes after delivery. 79.1% of the babies weighed between 2.5 kgm and 3.9 kgm. Pre-eclamptic toxaemia was the commonest complication in pregnancy followed by Urinary Tract Infection and Polyhydramnios. Postpartum complications in the mother were confined to 14 women (6.2%), and wound infection or breakdown was the commonest cause.

HLA and Chinese patients with juvenile onset diabetes mellitus

The HLA profile of 147 Chinese patients with juvenile onset diabetes mellitus was studied. There were HLA associations related to different age of onset of the disease. The patients who presented during the first decade of life had strong linkages with AW 33, B 17 and BW 22 (BW 54/55) but a weak association with DR 4. In contrast, patients whose age of onset ranged from 31 to 39 years had increased frequency of BW 46. Patients with diabetic complications (retinopathy, nephropathy, neuropathy and peripheral vascular disease) which were present singly or in combination were associated with HLA AW 33 and B 17. It would appear that genetic factor may be related to both the age of onset of diabetes as well as to the development of complications.

Home blood glucose monitoring, glycaemic control and diabetic complications

The aim of this study was to evaluate the effect of home blood glucose monitoring on diabetic complications and metabolic control. Forty Chinese and Indian patients participated in the Diabetic Society of Singapore National Home Blood Glucose Monitoring (HBGM) Programme. The clinical progress, the blood glucose and glycosylated haemoglobin concentrations, and the platelet aggregation of the aforementioned patients were studied over a 6-month period; the results were compared with those from a matched, albeit smaller, control group of 18 diabetic patients who were on treatment but not in the HBGM programme. At the end of the six month period, three patients in the control group showed clinical deterioration of peripheral neuropathy in contrast to one patient on HBGM. Due to the small number of patients, the difference in the findings was not statistically significant. Patients on HBGM demonstrated significant improvement in mean grouped blood glucose profile values, 135 +/- 8 to 118 +/- 5 mg/dl, p less than 0.01, and glycosylated haemoglobin levels, 10.3 +/- 0.4 to 9.3 +/- 0.3%, p less than 0.01. The platelet aggregability was unchanged. In contrast, patients in the control group developed a significant increase in platelet aggregation (30 +/- 4% to 37 +/- 5%, p less than 0.05), although the blood glucose and glycosylated haemoglobin concentrations were not significantly altered. This study demonstrated that patients on a six-month HBGM programme were able to achieve improved glycaemic control associated with a trend towards decreased deterioration of diabetic neuropathy and platelet aggregability.

Diabetic amputees in Singapore

We studied the clinical features of 262 consecutive patients who had 289 limb amputations in the University Department of Orthopaedics, Singapore General Hospital from January, 1978 to June, 1980. Of these, 171 (59.2%) were done for diabetic complications, 43 (14.9%) for trauma and 27 (9.3%) for atherosclerosis. The mean age of the three groups were 65 +/- 10 (S.D.), 32 +/- 17, and 75 +/- 8 years respectively. The indications for amputation in diabetics were gangrene (36%), ulcer (25%), infection (14%), gangrene and ulcer (11%), gangrene and infection (8.2%), and ulcer and infection (6%). The majority of diabetics were treated with oral agents (80.2%) and diet (6.4%), with 13.4% on insulin. Most patients had their diabetes for less than ten years-38.6% less than five years and 30.7% six-ten years. The mean known duration of the lesion was 1.13 +/- 1.42 months, with 38.7% less than one week. To determine the prevalence of peripheral vascular disease in diabetics admitted for amputation, the ankle/arm systolic BP ratio at rest and post-exercise were determined. In the affected leg, 16/19 patients had decreased ankle/arm systolic BP ratio. In another study, 23/26 diabetic amputees had decreased ankle/arm systolic BP ratio in the remaining leg. These data suggest that diabetes is the most common indication for amputation in this study. Most of these patients are Type II diabetics and have peripheral vascular disease.

Thyrotoxicosis and thyroid cancer

It is generally held that thyroid cancer is uncommonly associated with thyrotoxicosis. We report here nine patients with thyroid cancer amongst 720 patients with thyrotoxicosis. Three patients presented with features of malignancy together with thyrotoxicosis (Group A), one of whom had triiodothyronine (T3)-toxicosis. The remaining six patients were diagnosed following histological examination of tissues removed during subtotal thyroidectomies for hyperthyroidism (Group B). Two patients in Group A had follicular carcinoma; the rest were papillary in type. All the patients were rendered euthyroid initially, followed by ablative therapy for two patients in Group A and four patients in Group B. All but one are alive after one to nine years (mean of 3 . 4 years). The diagnosis of thyroid carcinoma is infrequently considered in the presence of thyrotoxicosis. The association is not clinically apparent in the majority of patients. The optimum management of such occult malignancies in thyrotoxicosis remains to be defined.

Risk factors for screening potential diabetics in pregnant Chinese patients

An intensive screening programme for potential diabetics in pregnancy was conducted in the University Department of Obstetrics and Gynaecology, Kandang Kerbau Hospital, Singapore, from June 1978 to December 1980. All patients with one or more risk factors for potential diabetes underwent an oral glucose tolerance tests (OGTT) with 50 g glucose loads. An abnormal OGTT was defined as one in which the second hour venous plasma glucose value was 7.8 mmol/1 (140 mg%) or more. In a group of 789 Chinese patients aged between 20 and 40 years, the overall detection rate of abnormal OGTTs was 15.5%. A significantly high proportion of abnormal OGTTs was found in patients with a direct family history of diabetes associated with random glycosuria during pregnancy and those with a previous history of 2 or more consecutive spontaneous abortions. However, in view of the relatively low detection rate of abnormal OGTTs in pregnant potential diabetics, a preliminary blood screening test would be useful to select those patients who require full OGTTs.

Acute carpal tunnel syndrome secondary to thrombosis of a persistent median artery (with high division of the median nerve). A case report

An unusual case of median nerve compression due to thrombosis of a persistent median artery with a high division of the median nerve is described. The most probable case of the thrombosis is probably the repeated stretch and vibration that is associated with the use of a stiff clutch in a new motor cycle. This report serves to emphasise the need for early diagnosis and in immediate decompression in such cases. The use of an adequate incision for good exposure of the carpal tunnel and all its contents is recommended.

HLA and thyrotoxicosis (Graves' disease) in Chinese

HLA locus A and B typing was performed on 86 Chinese thyrotoxicosis (Graves' Disease) patients and 238 normal Chinese subjects. The frequency of HLA-Bw46 (Sin 2) was found to be significantly higher among the patients than controls (x2 = 26.15, corrected P less than .003, relative risk = 3.74). The risk associated with Bw46 was reflected in the Bw46 heterozygotes. The relative risks of the joint occurrence of Bw46/B40 and Bw46/B13 were 8.74 and 5.88 respectively.

Magnesium-saving property of an aldosterone antagonist in the treatment of oedema of liver cirrhosis

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Contaminants in commercial dapsone

Three contaminants commonly found in commercial dapsone were identified as 2,4'-sulfonylbis(benzeneamine), 4-(phenylsulfonyl)benzeneamine, and 4-(4'-chlorophenylsulfonyl)benzeneamine. The identities were based on the spectral analysis and unambiguous synthesis of each compound. Solvent-free, pure dapsone was prepared by recrystallization from chloroform.

Calcium and phosphorus metabolism in nephrotic syndrome

Calcium and phosphorus balance studies were performed on 13 nephrotic patients and eight patients during clinical remission of the nephrotic syndrome. Marked impairment of intestinal absorption of calcium was found among nephrotic patients, in eight of whom faecal calcium equalled or exceeded dietary calcium. The mean faecal:dietary calcium ratio of nephrotic patients, 1-06 +/- 0-23 (SD), was significantly higher (p less than 0-005) than that of patients in remission, 0-58 +/- 0-21 (SD). The mean 24-hour urinary excretion of calcium of nephrotic patients, 0-68 +/- 0-68 (SD) mmol, was significantly lower (p less than 0-005) than that of patients in remission, 3-02 +/- 1-91 (SD) mmol. Calciferol administered to three nephrotic patients in the dosage of 1.25 mg per day did not significantly influence intestinal absorption or renal excretion of calcium. There was no difference between the two groups of patients in intestinal absorption or renal excretion of phosphorus; there was net intestinal absorption in all subjects. Quantitative bone histology was studied in seven of the nephrotic patients. None had osteomalacia or osteitis fibrosa, while only one had evidence of mild osteoporosis.

Pseudohypoparathyroidism associated with cri du chat syndrome

A case is reported in which features of pseudohypoparathyroidism were found in association with the cri du chat syndrome. This association may throw some light on the localization of the chromosomal abberration which underlies pseudohypoparathyroidism, since deletion of the short arm of chromosome 5 has been clearly established in the cri du chat syndrome.

T3 toxicosis and its relation to the iodide status in Singapore

Baseline thyroid function tests (including total serum thyroxine iodide-T4I, total serum tri-iodothyronine T3 as well as T3 Sephadex Uptake Studies (T3U)) were determined in 82 normal Asian subjects. In addition, another group of normal volunteers (39) were assessed as regard serum and 24-hour urinary iodide levels to gauge the iodide status of the community; the results were comparable to that of goitre-free regions of the world. Having established the range of values of normal thyroid function tests, 103 consecutive clinically thyrotoxic patients (both new and relapsed cases) were similarly studied in an attempt to elucidate the magnitude of the problem of T3 toxicosis, and its relation to the iodide status in Singapore. Only three clinically hyperthyroid patients were foudn to have normal PBI T3 levels. A detailed analysis and discussion of the data is presented. It is concluded that T3 toxicosis is a rarity in Singapore.

Serum ionized calcium in nephrotic syndrome

Serum ionized calcium was measured in 12 patients with nephrotic syndrome and 14 nephrotic patients during clinical remission. All subjects had normal creatinine clearance and were not receiving treatment at the time of study. The mean serum ionized calcium values of the two groups of patients, 1-08 +/- 0-10 (SD) mmol/l ultrafiltrate and 1-21 +/- 0-10 (SD) mmol/l ultrafiltrate respectively, are significantly lower than the normal mean (1-28 +/- 0-06 (SD) mmol/l ultrafiltrate). The mean values of the patients in remission is, however, significantly higher (P less than 0-005) than that of the patients with manifest nephrotic syndrome. Elevated serum complexed calcium, and high serum protein-bound calcium in relation to serum albumin, were encountered, being more apparent in patients with overt nephrotic syndrome.

Elevated serum enzymes in patients with wasp/bee sting and their clinical significance

Seventeen patients who had been admitted to hospital for wasp/bee sting were studied. Mild pyrexia was encountered in 7 patients, rash/urticaria in 3, angioneurotic oedema in 2, oliguria in 2, microscopic haematuria and albuminuria in 3, transient hypotension in 1. However, there were frequent elevations of serum glutamic-oxaloacetic transaminase (9 out of 17 patients), serum creatine phosphokinase (14 out of 17 patients) and serum lactate dehydrogenase (8 out of 14 patients), indicating presence of damage to muscle fibres. This was confirmed by the histological findings of a muscle-biopsy from the most severe case. Elevation of serum glutamic-pyruvic transaminase was found in 6, and elevation of serum isocitrate dehydrogenase in 5 out of 14 patients, suggesting presence of liver damage. The above enzyme elevations appeared short-lived except in the clinically most severe patient (case 9) who developed acute tubular necrosis. All patients except the latter suffered no clinical sequelae and there was no correlation between their clinical condition and the presence or degree of elevations of serum enzymes.

Recurrent ventricular tachycardia in hypothyroidism

Ventricular tachycardia associated with myxoedema is rare. Only two cases have so far been documented. In the report by Hansen, the patient had recurrent chest pain which suggested coexisting coronary heart disease. In the second case, the patient developed recurrent ventricular tachycardia only after intravenous triiodothyronine was given. This paper reports a further case of hypothyroidism with recurrent episodes of ventricular tachycardia and ventricular fibrillation which was not associated with any of the established causes of this arrhythmia.

Magnesium deficiency in patients on long-term diuretic therapy for heart failure

Magnesium levels in serum, erythrocytes, skeletal muscle, and bone were measured in 10 patients with valvular heart disease who had received diuretic therapy for heart failure for an average of 3.3 years. Five patients were found to have diminished values for skeletal muscle, indicating significant magnesium deficit. Values for erythrocytes were low in only two of the five patients, and none had low values for serum ultrafiltrate and bone: Magnesium replacement therapy restored skeletal muscle values to normal. Clinical features consistent with the presence of magnesium deficiency were found in all five magnesium-deficient patients. These features were, with few exceptions, corrected by magnesium replacement. The latter also corrected low skeletal muscle potassium values present in all five patients with low skeletal muscle magnesium, four of whom showed clinical features of digoxin poisoning before magnesium therapy was given. Concomitant secondary aldosteronism, inadequate dietary intake, and digoxin therapy had probably augmented the magnesium loss due to diuretic therapy.