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C Cockram

Publications and source records attributed to C Cockram.

11 recordsLinked to original sources
PubMed2001

HLA typing and immunological characterization of young-onset diabetes mellitus in a Hong Kong Chinese population.

AIMS: A study of the Hong Kong Chinese showed that the majority of subjects with young-onset diabetes (age of diagnosis < 35 years) present with a phenotype suggestive of Type 2 diabetes mellitus, although up to 50% subsequently need insulin treatment. The aim of this study was to use a combination of clinical, genetic and immunological markers to characterize the disease phenotype further in such individuals and to determine whether the requirement for insulin is the result of autoimmune disease. METHODS: One hundred and thirty-seven Hong Kong Chinese with young-onset diabetes were studied, irrespective of their mode of presentation. The subjects were typed for alleles of the HLA-DR and -DQ genes and investigated for the presence of autoantibodies to glutamic acid decarboxylase (GAD). Plasma C-peptide concentration and requirement for insulin were also determined. RESULTS: One hundred and three subjects presented with a syndrome resembling Type 2 diabetes, while 34 presented with Type 1 diabetes. Of the former group, 35 patients (34.0%) were insulin-deficient, 16 (15.5%) were insulin-treated and seven (6.9%) were positive for GAD autoantibodies. Among the GAD-positive subjects presenting with Type 2 diabetes, the HLA-DRB1*03 allele may be a marker of early progression to insulin therapy. CONCLUSIONS: Seven subjects with Type 2 diabetes at presentation had autoantibodies to GAD. Causes other than GAD autoimmunity, however, must be sought to explain the high prevalence of insulin deficiency observed in the Chinese patients. This study highlights the heterogeneity of the pathogenic processes leading to the diabetic phenotype.

Adolescent↗
PubMed2000

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Journal Article↗
PubMed1998

Lack of association between polymorphism of the thyrotropin receptor gene and Graves' disease in United Kingdom and Hong Kong Chinese patients: case control and family-based studies.

The thyrotropin receptor (TSH-R) gene is a candidate for genetic susceptibility to Graves' disease (GD). Previous case control studies investigating allelic association of a polymorphism at position 253 (C253 to A253) of the TSH-R gene have shown conflicting results. We genotyped two independent case control datasets (UK Caucasian and Hong Kong Chinese), for the A253 polymorphism. The Transmission Disequilibrium Test was also used in a third family-based dataset that included 89 UK Caucasian families (both parents, a GD sibling and an unaffected sibling). Genotyping was performed by polymerase chain reaction (PCR)-amplification of genomic DNA and Tth111 I restriction enzyme digestion. No difference in frequencies of the A253 polymorphism between GD (21/204, 10.3%) and controls (34/358, 9.5%) was found in the UK Caucasians (chi2 = 0.093; p = NS). A similar finding was observed in GD (0/96, 0%) and controls (2/71, 2.8%) in Hong Kong Chinese subjects (chi2 = 2.73; p = NS). Results from the 89 UK families showed no deviation from the expected transmission frequency of 0.5, from parents heterozygous for the A253 allele to either Graves' or unaffected offspring (Fisher's exact test p = 0.22) and, therefore, confirmed a lack of evidence of linkage disequilibrium between the A253 allele and GD.

Alleles↗
PubMed1997

The mitochondrial tRNA[Leu(UUR)] A to G 3243 mutation is associated with insulin-dependent and non-insulin-dependent diabetes in a Chinese population.

The mitochondrial DNA tRNA[Leu(UUR)] A to G 3243 mutation is associated with maternally inherited diabetes in Caucasians and Japanese. In a Hong Kong Chinese population we have detected the 3243 mutation in 2 of 74 unrelated subjects with well characterized insulin-dependent (Type 1) diabetes mellitus (IDDM) and 2 of 75 unrelated subjects with young onset (<35 years) non-insulin-dependent diabetes (NIDDM). The 3243 mutation has only previously been associated with IDDM in Japanese. Racial differences in association of the mitochondrial 3243 mutation with IDDM suggest the influence of other genes that may increase its diabetogenic pathogenicity in Oriental races. We also found a significant excess of maternal inheritance of diabetes in the young onset NIDDM cohort, with a ratio of diabetic mothers to fathers of 2.4:1, p < 0.005. The 3243 mutation, however, only accounts for a small proportion of the observed excess maternal inheritance, and further study is needed to search for other diabetes associated mitochondrial DNA mutations.

Adolescent↗
PubMed1996

Water and sodium disorders following surgical excision of pituitary region tumours.

A prospective observational study of the pathophysiology of sodium and water disorders in patients with pituitary region tumours after surgical excision was carried out in 20 patients. Serial pre-operative and post-operative fluid and sodium balance, plasma and urine elctrolyte biochemistry and their derived parameters, and circulating hormones associated with fluid balance, atrial natriureic peptide (ANP) and antidiuretic hormone (ADH) were documented to correlate with the patients' clinical conditions. Ten out of these twenty cases developed diabetes insipidus (DI) requiring ADH replacement therapy, although in the majority (6 cases), this way only a transient event. Of the nine patients who developed hyponatraemia, six had symptoms such as impaired consciousness and convulsions. Four patients developed alternating hypoatraemia and hypernatraemia, which constituted a difficult group, where appropriate sodium and fluid management, and ADH replacement therapy were based upon twice daily plasma and urine biochemistry and their derived parameters. Whilst DI in this group of patients was the result of a low circulating ADH level, hyponatraemia was not associated with an exaggerated ADH activity (6.0 +/- 2.3 vs 7.4 +/- 2.3 pmol/ml, mean +/- SEM). Rather, hyponatraemia was strongly associated with an elevated circulating ANP concentration (82.4 +/- 10.5 vs 30.0 +/- 3.1 pmol/ml, mean +/- SEM, p < 0.001), resulting in salt wasting and hypovolaemia.

Adolescent↗
PubMed1994

Association between serum uric acid and some cardiovascular risk factors in a Chinese population.

The association between serum uric acid concentration and some cardiovascular risk factors was examined in a working Hong Kong Chinese population (mean age 38 years), consisting of 910 men and 603 women. There was no significant age-related rise in serum uric acid concentration. Positive associations were found between serum uric acid concentration and body mass index, waist hip ratio, systolic and diastolic blood pressure, urea, creatinine, protein, glucose (fasting and 2 hours after 75 g oral glucose load), 2 hour insulin, triglycerides, and apolipoprotein B in men. Similar, but fewer, associations were seen in women, with the addition of a positive association with age. In both sexes, serum uric acid was negatively associated with high-density lipoprotein cholesterol. These findings complement the well-known clinical association between gout and cardiovascular and metabolic diseases, such as hypertension, hyperlipidaemia and diabetes mellitus, and suggest that serum uric acid may be a marker for the presence of an adverse cardiovascular risk factor profile.

Adult↗
PubMed1993

Adrenocortical function and involvement in high risk cases of pulmonary tuberculosis.

SETTING: A regional hospital in Hong Kong. OBJECTIVE: To evaluate adrenocortical function in older patients admitted to hospital with active pulmonary tuberculosis (TB) and to determine whether adrenal insufficiency contributes to mortality in this high risk group. DESIGN: Adrenocortical function was assessed in 39 consecutive patients aged over 50 admitted to hospital with active pulmonary TB. Short Synacthen stimulation tests were performed before treatment and repeated at 2 months. In patients who died during treatment, a post-mortem examination was performed. Particular attention was paid to TB involvement of the adrenal glands. RESULTS: None of the patients had a subnormal basal cortisol concentration before treatment. 7 (18%) had raised basal cortisol concentrations and 16 (41%) had suboptimal cortisol responses to Synacthen stimulation. 14 patients (36%) died during treatment. The basal cortisol concentrations were significantly higher in the non-survivors compared to the survivors (743.7 +/- 288.5 vs 460.5 +/- 123.2 nmol/L, P < 0.0001). Autopsies were performed in 9 patients who died during treatment. Tuberculous involvement of the adrenal glands was found in only 1 patient who had a high basal cortisol concentration. After 2 months of treatment, all patients had normal cortisol concentrations and only 4 had borderline suboptimal Synacthen responses. The basal cortisol concentrations were significantly higher at presentation compared to those at 2 months after treatment (570.4 +/- 243.8 vs 386.3 +/- 108.3 nmol/L, P = 0.0014). CONCLUSION: Adrenal insufficiency is uncommon in patients with pulmonary TB. Suboptimal cortisol responses to Synacthen usually reflect a hyperstimulated basal state secondary to stress. Treatment with anti-TB drugs causes reduction in basal cortisol with associated improvement in the Synacthen response.

Adrenal Cortex↗
PubMed1992

Influence of obesity on plasma fructosamine concentration.

The influence of obesity on plasma fructosamine concentration was studied in 68 diabetic and 1335 nondiabetic subjects from a Chinese community. Obese nondiabetic men (body mass index > 25 kg/m2) had lower fructosamine concentrations than nonobese nondiabetic men (body mass index < or = 25 kg/m2); the pattern was similar for diabetic women. Stepwise multiple-regression analysis showed that, apart from known factors (total protein, albumin, and indices of glycemic control), fructosamine was also associated with body mass index and plasma fasting triglycerides. However, the contribution of these were small except in diabetic women. We conclude that the effect of obesity on fructosamine is small.

Adult↗
PubMed1992

Blood pressure and urinary cations in a Chinese population.

The prevalence of hypertension and the relationship between blood pressure, age, body mass index (BMI) and urinary cations from casual urine specimens were examined in 1,513 Chinese employees of a public utility company and non-medical personnel of a district hospital. The prevalence of hypertension, defined as systolic blood pressure greater than or equal to 140 or a diastolic blood pressure greater than or equal to 90 mmHg, or a past history of hypertension, was 17% in men and 5% in women. After excluding subjects who were on antihypertensive medication, age, body mass index, and urinary sodium/potassium ratio were independently and positively associated with blood pressure, while urinary potassium/creatinine ratio was inversely related to blood pressure. No association with urinary sodium or sodium/creatinine ratio was found. Higher mean blood pressure in men was accompanied by lower urinary potassium/creatinine and potassium concentration and higher sodium/potassium ratio, even though men had the same mean BMI when compared with women. A difference in potassium intake between the sexes may partly account for this finding. We conclude that in this Chinese population, whose dietary intake is more influenced by the West compared with Chinese in the Peoples' Republic of China, age and BMI are important determinants of blood pressure, together with potassium intake as reflected by urinary potassium excretion. No association of blood pressure with sodium excretion was demonstrated.

Adolescent↗
PubMed1987

The prevalence of diabetes mellitus and an assessment of methods of detection among a community of elderly Chinese in Hong Kong.

This study provides information on the prevalence of diabetes mellitus in a group of elderly Chinese subjects aged 60 and above living in the community in Hong Kong, and investigates the sensitivity of the urine sugar, random blood glucose, glycosylated haemoglobin, and fructosamine measurements compared to a glucose tolerance test in screening for diabetes mellitus in this population. Four hundred twenty-seven subjects aged 60 and above were studied. The National Diabetes Data Group Criteria were used for the diagnosis of diabetes. Those with a random blood glucose exceeding 12.5 mmol/l were considered diabetic, and all of these patients had glycosuria together with elevated total glycosylated haemoglobin and fructosamine concentrations. A diagnostic 75 g oral glucose tolerance test was performed on patients with one or more of the following abnormalities: glycosuria, random plasma blood glucose 7.8 mmol/l to 12.5 mmol/l, glycosylated haemoglobin 8.5%, and fructosamine 2.20 mmol/l. By these criteria, the prevalence of diabetes in this community was found to be 9.8%. An elevated random glucose greater than 11.1 mmol/l proved to be the only specific method of screening and glycosuria was found to be at least as good as fructosamine and HbA1. However, HbA1 is more sensitive than random glucose, glycosuria or fructosamine in detecting impaired glucose tolerance. On the basis of this study, a higher reference range for glycosylated haemoglobin for the elderly alone is also suggested (5.74-9.34%).

Aged↗