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Chong SC, Law LK, Hui J, Lai CY, Leung TY, Yuen YP. Expanded newborn metabolic screening programme in Hong Kong: a three-year journey. Hong Kong Med J 2017; 23:489-96. [PMID: 28862145 DOI: 10.12809/hkmj176274] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
INTRODUCTION No universal expanded newborn screening service for inborn errors of metabolism is available in Hong Kong despite its long history in developed western countries and rapid development in neighbouring Asian countries. To increase the local awareness and preparedness, the Centre of Inborn Errors of Metabolism of the Chinese University of Hong Kong started a private inborn errors of metabolism screening programme in July 2013. This study aimed to describe the results and implementation of this screening programme. METHODS We retrieved the demographics of the screened newborns and the screening results from July 2013 to July 2016. These data were used to calculate quality metrics such as call-back rate and false-positive rate. Clinical details of true-positive and false-negative cases and their outcomes were described. Finally, the call-back logistics for newborns with positive screening results were reviewed. RESULTS During the study period, 30 448 newborns referred from 13 private and public units were screened. Of the samples, 98.3% were collected within 7 days of life. The overall call-back rate was 0.128% (39/30 448) and the false-positive rate was 0.105% (32/30 448). Six neonates were confirmed to have inborn errors of metabolism, including two cases of medium-chain acyl-coenzyme A dehydrogenase deficiency, one case of carnitine-acylcarnitine translocase deficiency, and three milder conditions. One case of maternal carnitine uptake defect was diagnosed. All patients remained asymptomatic at their last follow-up. CONCLUSION The Centre of Inborn Errors of Metabolism has established a comprehensive expanded newborn screening programme for selected inborn errors of metabolism. It sets a standard against which the performance of other private newborn screening tests can be compared. Our experience can also serve as a reference for policymakers when they contemplate establishing a government-funded universal expanded newborn screening programme in the future.
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Affiliation(s)
- S C Chong
- Centre of Inborn Errors of Metabolism, The Chinese University of Hong Kong, Shatin, Hong Kong.,Department of Paediatrics, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - L K Law
- Centre of Inborn Errors of Metabolism, The Chinese University of Hong Kong, Shatin, Hong Kong.,Department of Chemical Pathology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - J Hui
- Centre of Inborn Errors of Metabolism, The Chinese University of Hong Kong, Shatin, Hong Kong.,Department of Paediatrics, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - C Y Lai
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - T Y Leung
- Centre of Inborn Errors of Metabolism, The Chinese University of Hong Kong, Shatin, Hong Kong.,Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - Y P Yuen
- Centre of Inborn Errors of Metabolism, The Chinese University of Hong Kong, Shatin, Hong Kong.,Department of Chemical Pathology, The Chinese University of Hong Kong, Shatin, Hong Kong
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2
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Hui J, Chong SC, Law LK, Lee LK, Chang S, Yau P, Yuen YP. One too many: intellectual disability secondary to undiagnosed phenylketonuria. Hong Kong Med J 2016; 22:506-8. [PMID: 27738300 DOI: 10.12809/hkmj144500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- J Hui
- Department of Paediatrics, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - S C Chong
- Department of Paediatrics, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - L K Law
- Department of Chemical Pathology, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - L K Lee
- Department of Paediatrics, The Chinese University of Hong Kong, Shatin, Hong Kong
| | - S Chang
- Dietetics Department, Prince of Wales Hospital, Shatin, Hong Kong
| | - P Yau
- Dietetics Department, Prince of Wales Hospital, Shatin, Hong Kong
| | - Y P Yuen
- Department of Chemical Pathology, The Chinese University of Hong Kong, Shatin, Hong Kong
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Law LK, Tang NLS, Lam CWK, Tong MKH, Mak TWL, Zhang WM, Wanders RJA. Novel missense mutations in the first Chinese patient with very-long-chain acyl-CoA dehydrogenase deficiency. Clin Chim Acta 2007; 375:173-4. [PMID: 16982043 DOI: 10.1016/j.cca.2006.07.028] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2006] [Revised: 07/31/2006] [Accepted: 07/31/2006] [Indexed: 11/19/2022]
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5
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Tang NLS, Hui J, Yong CKK, Wong LTK, Applegarth DA, Vallance HD, Law LK, Fung SLM, Mak TWL, Sung YM, Cheung KL, Fok TF. A genomic approach to mutation analysis of holocarboxylase synthetase gene in three Chinese patients with late-onset holocarboxylase synthetase deficiency. Clin Biochem 2003; 36:145-9. [PMID: 12633764 DOI: 10.1016/s0009-9120(02)00432-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Multiple carboxylase deficiency (MCD, MIM:253270) is a common organic aciduria and caused by deficiency of either biotinidase or holocarboxylase synthetase (HLCS; EC 6.3.4.10). Patients commonly present during early infancy with acute metabolic derangements and severe metabolic acidosis. Recently, a late onset form of HLCS deficiency was also described. The different phenotypes (early and late presenting) may be related to a spectrum of mutations in HLCS gene. Applications of mutation analysis in HLCS had been limited previously by the requirement of cDNA from living tissue for study. We described here a genomic approach for molecular diagnosis of HLCS deficiency which we have used to detect mutations in Chinese patients who had the late-onset form of HLCS deficiency. In addition, a fibroblast cell line with MCD from Coriell Cell repositories was also studied. DESIGN AND METHODS Three Chinese patients with late onset HLCS deficiency were studied. The genomic sequence of HLCS was retrieved and newly designed primers were used to cover all coding sequences of the gene. PCR products were analyzed by direct sequencing. Population allelic frequencies of mutations detected were determined by genotyping of control samples by restriction fragment length polymorphism. RESULTS We found a recurrent mutation, R508W, in the three unrelated Chinese patients. Two were homozygous for this mutation. The other patient was a compound heterozygote of R508W and a novel mutation, D634N. The results suggest that R508W may be an important and relatively prevalent disease-causing mutation in Chinese MCD patients. A fibroblast cell-line from an African patient revealed an additional novel mutation, R565X and a known mutation, V550M. CONCLUSION R508W is a recurrent mutation in Chinese MCD patients which is associated with the late onset phenotype. This new genomic approach for mutation analysis of HLCS gene provides new opportunities in studies of MCD.
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Affiliation(s)
- Nelson L S Tang
- Department of Chemical Pathology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, Hong Kong.
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6
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Ho CS, Lam CWK, Chan MHM, Cheung RCK, Law LK, Lit LCW, Ng KF, Suen MWM, Tai HL. Electrospray ionisation mass spectrometry: principles and clinical applications. Clin Biochem Rev 2003; 24:3-12. [PMID: 18568044 PMCID: PMC1853331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This mini-review provides a general understanding of electrospray ionisation mass spectrometry (ESI-MS) which has become an increasingly important technique in the clinical laboratory for structural study or quantitative measurement of metabolites in a complex biological sample. The first part of the review explains the electrospray ionisation process, design of mass spectrometers with separation capability, characteristics of the mass spectrum, and practical considerations in quantitative analysis. The second part then focuses on some clinical applications. The capability of ESI-tandem-MS in measuring bio-molecules sharing similar molecular structures makes it particularly useful in screening for inborn errors of amino acid, fatty acid, purine, pyrimidine metabolism and diagnosis of galactosaemia and peroxisomal disorders. Electrospray ionisation is also efficient in generating cluster ions for structural elucidation of macromolecules. This has fostered a new and improved approach (vs electrophoresis) for identification and quantification of haemoglobin variants. With the understanding of glycohaemoglobin structure, an IFCC reference method for glycohaemoglobin assay has been established using ESI-MS. It represents a significant advancement for the standardisation of HbA1c in diabetic monitoring. With its other applications such as in therapeutic drug monitoring, ESI-MS will continue to exert an important influence in the future development and organisation of the clinical laboratory service.
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Affiliation(s)
- CS Ho
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - CWK Lam
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - MHM Chan
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - RCK Cheung
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - LK Law
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - LCW Lit
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - KF Ng
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - MWM Suen
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
| | - HL Tai
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
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7
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Abstract
We report elevated urinary excretion of 3-methylglutaconic (3MGC) and 3-methylglutaric acids (3MGR) in a patient with glycogen storage disease Ib. Combined excretion was 10-fold elevated in comparison to control during inadequate glucose maintenance, and still elevated following dietary improvement. 3MGC acid excretion correlated with plasma lactate and glucose. We speculate that imbalanced gluconeogenesis and de novo cholesterol synthesis result in secondarily increased 3MGC/3MGR production.
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Affiliation(s)
- L K Law
- Department of Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, N.T., Hong Kong, SAR.
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8
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Tang NLS, Hwu WL, Chan RT, Law LK, Fung LM, Zhang WM. A founder mutation (R254X) of SLC22A5 (OCTN2) in Chinese primary carnitine deficiency patients. Hum Mutat 2002; 20:232. [PMID: 12204000 DOI: 10.1002/humu.9053] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Mutations in the SLC22A5 gene, which encodes for the plasma membrane carnitine transporter OCTN2, cause primary carnitine deficiency (PCD). After our first report of OCTN2 mutations in Chinese, three more Chinese PCD patients were identified. The parents of these families were non-consanguineous and these families were unrelated. Two novel truncating mutations were found: R254X, a single-base mutation at cDNA position 981 (c.981C>T); and Y387X (c.1382T>G). Two probands, one each from Taiwan and Macau, were homozygous for R254X. The other proband from Taiwan carried both R254X and Y387X. Two additional heterozygote carriers of R254X were also identified among 250 control samples, while none was detected for Y387X. The population carrier rate for R254X would be about 1 in 125. Haplotypes of R254X alleles were examined and patients homozygous for R254X were also homozygous for the same haplotype of intragenic and microsatellites markers. Analysis of population frequencies of haplotypes revealed that the chance of 4 chromosomes having arisen as independent events was 0.016. We conclude that R254X is probably a founder mutation in Chinese. Other previously reported mutations found in the Japanese population were also screening in 250 control samples but no carrier was identified, indicating that they were either very rare or not present in Southern Chinese.
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Affiliation(s)
- Nelson L S Tang
- Department of Chemical Pathology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong.
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9
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Tang NL, Hui J, Law LK, To KF, Mak TW, Cheung KL, Vreken P, Wanders RJ, Fok TF. Overview of common inherited metabolic diseases in a Southern Chinese population of Hong Kong. Clin Chim Acta 2001; 313:195-201. [PMID: 11694259 DOI: 10.1016/s0009-8981(01)00673-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND The Joint metabolic clinic at the Prince of Wales Hospital was established in January 1997 to provide a comprehensive multi-disciplinary care to patients with inherited metabolic diseases (IMDs). Patients are referred from both within and outside our hospital. Until July, 2000, more than 40 patients and families with 20 different biochemical diagnoses attend the clinic for regular follow up. A pattern of more common IMDs among Hong Kong Chinese emerged from our case registry. In order to advance the understanding of Chinese metabolic diseases, we examined the molecular basis of those diseases with unique features in Chinese or were locally prevalent. Mutations were found in patients with primary carnitine deficiency, ornithine transcarbamylase deficiency, X-linked adrenoleukodystrophy, glutaric aciduria type I, and galactosemia. We also analyzed the mutations in multiple carboxylase deficiency and Niemann-pick type C on four families. CONCLUSIONS Although IMDs are a significant cause of mortality and morbidity among pediatric patients, with a better understanding of the molecular genetics of these diseases, prenatal diagnosis of these common IMDs will be facilitated, which is currently the most effective way of controlling IMDs.
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Affiliation(s)
- N L Tang
- Department of Chemical Pathology, Faculty of Medicine, The Chinese University of Hong Kong, Shatin, SAR, Hong Kong, People's Republic of China.
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10
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Dekker J, Eppink MH, van Zwieten R, de Rijk T, Remacha AF, Law LK, Li AM, Cheung KL, van Berkel WJ, Roos D. Seven new mutations in the nicotinamide adenine dinucleotide reduced-cytochrome b(5) reductase gene leading to methemoglobinemia type I. Blood 2001; 97:1106-14. [PMID: 11159544 DOI: 10.1182/blood.v97.4.1106] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cytochrome b(5) reductase (b5R) deficiency manifests itself in 2 distinct ways. In methemoglobinemia type I, the patients only suffer from cyanosis, whereas in type II, the patients suffer in addition from severe mental retardation and neurologic impairment. Biochemical data indicate that this may be due to a difference in mutations, causing enzyme instability in type I and complete enzyme deficiency or enzyme inactivation in type II. We have investigated 7 families with methemoglobulinemia type I and found 7 novel mutations in the b5R gene. Six of these mutations predicted amino acid substitutions at sites not involved in reduced nicotinamide adenine dinucleotide (NADH) or flavin adenine dinucleotide (FAD) binding, as deduced from a 3-dimensional model of human b5R. This model was constructed from comparison with the known 3-dimensional structure of pig b5R. The seventh mutation was a splice site mutation leading to skipping of exon 5 in messenger RNA, present in heterozygous form in a patient together with a missense mutation on the other allele. Eight other amino acid substitutions, previously described to cause methemoglobinemia type I, were also situated in nonessential regions of the enzyme. In contrast, 2 other substitutions, known to cause the type II form of the disease, were found to directly affect the consensus FAD-binding site or indirectly influence NADH binding. Thus, these data support the idea that enzyme inactivation is a cause of the type II disease, whereas enzyme instability may lead to the type I form.
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Affiliation(s)
- J Dekker
- Central Laboratory of the Netherlands Blood Transfusion Service (CLB), and Laboratory for Experimental and Clinical Immunology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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11
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Abstract
A newborn infant who presented with central cyanosis was found to have hereditary methaemoglobinaemia. The pulse oximeter readings and physical findings were incompatible. Clinical assessment remains an important part in the management of such cases.
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Affiliation(s)
- A M Li
- Departments of Paediatrics, Prince of Wales Hospital, Chinese University of Hong Kong, Shatin, Hong Kong, China
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12
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Abstract
Glutaric acidemia type I is caused by mutations of the glutaryl-CoA dehydrogenase (GCDH) gene resulting in loss of GCDH enzyme activity. Patients present with progressive dystonia and lesions in basal ganglia. Dietary treatment, when instituted from the early neonatal period, markedly reduces dystonia and morbidity. Early diagnosis and prenatal diagnosis will be facilitated by knowledge of locally prevalent GCDH mutations. Several common GCDH mutations have been found in different ethnic groups. GCDH mutations were studied in 5 Chinese glutaric acidemia type I families. We detected two novel recurrent mutations (A219T and IVS10-2A>C) which were found in two unrelated families. An asymptomatic carrier of IVS10-2A>C was also found on screening of 120 individuals. Other mutations were identified, including two other novel (R386G & IVS3+1G>A) and two known mutations (G178R & R355H). Fibroblasts from patients carrying the novel mutations were confirmed to be deficient for GCDH activity. This is the first report of GCDH mutations describing recurrent mutations in Chinese patients. The carrier rate of IVS10-2A>C may be particularly high in Chinese.
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Affiliation(s)
- N L Tang
- Department of Chemical Pathology, The Chinese University of Hong Kong.
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13
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Tang NL, Hui J, Law LK, To KF, Cheung KL, Magnus HN, Yuen PM, Fok TF. Primary carnitine deficiency in the Chinese. Chin Med J (Engl) 2000; 113:376-80. [PMID: 11775240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Affiliation(s)
- N L Tang
- Department of Chemical Pathology, Faculty of Medicine, Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
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14
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Mellick GD, Buchanan DD, Silburn PA, Chan DK, Le Couteur DG, Law LK, Woo J, Pang CP. The monoamine oxidase B gene GT repeat polymorphism and Parkinson's disease in a Chinese population. J Neurol 2000; 247:52-5. [PMID: 10701898 DOI: 10.1007/s004150050010] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Monoamine oxidase B (MAOB) metabolises dopamine and activates neurotoxins known to induce parkinsonism in humans and primates. Therefore the MAOB gene (MAOB; Xp15.21-4) is a candidate gene for Parkinson's disease (PD). Longer length dinucleotide repeat sequences in a highly polymorphic GT repeat region of intron 2 of this gene showed an association with PD in an Australian cohort. We repeated this allele-association study in a population of 176 Chinese PD patients (90 men, 86 women) and 203 agematched controls (99 men, 104 women). Genomic DNA was extracted from venous blood and the polymerase chain reaction was used to amplify the appropriate regions of the MAOB gene. The length of each (GT) repeat sequence was determined by 5% polyacrylamide denaturing gel electrophoresis. There was no significant difference in allele frequencies of the (GT) repeat allelic variation between patients and controls (chi2 = 2.48; df = 5, P<0.75). Therefore the longer length GT repeat alleles are not associated with PD in this Chinese population. Possible reasons for the discrepancy between Chinese and Australian populations include a different interaction between this genetic factor and environmental factors in the two populations and the possibility that the long length GT repeat alleles may represent a marker mutation, genetically linked to another susceptibility allele in whites but not in Chinese. Methodological differences in the ascertainment of cases and controls in this cohort could also explain the observed differences. Further study is required to determine whether the longer length GT repeat alleles are true susceptibility alleles in PD.
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Affiliation(s)
- G D Mellick
- Department of Medicine, University of Queensland, Princess Alexandra Hospital, Woolloongabba, Australia
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15
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Abstract
The C766T polymorphism in exon 3 of the low-density lipoprotein receptor-related protein (LRP) gene is underrepresented in Alzheimer's disease (AD) compared with normal subjects. We examined this polymorphism in 186 patients with Parkinson's disease (PD) and 187 age-matched normal Chinese subjects in addition to 227 newborns representing the general population. The fraction of individuals with 766T was 12.8% in normal subjects and 11.3% in patients with PD, not a significant difference (p = 0.77). The odds ratio was 0.86 with a 95% confidence interval of 0.44-1.69, thus the LRP C766T polymorphism does not play a major role in risk for PD, although the possibility cannot be excluded that it plays a minor role or is a significant risk factor in other ethnic groups.
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Affiliation(s)
- L Baum
- Department of Ophthalmology and Visual Sciences, Chinese University of Hong Kong, Shatin, NT, China
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16
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Cheung KL, Tang N, Hsiao KJ, Law LK, Wong W, Ng PC, Pang CP, Applegarth DA, Fok TF, Hjelm NM. Classical galactosaemia in Chinese: A case report and review of disease incidence. J Paediatr Child Health 1999; 35:399-400. [PMID: 28871650 DOI: 10.1046/j.1440-1754.1999.00373.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We report a case of galactose-1-phosphate uridyl transferase (GALT) deficiency in a full-term Chinese neonate, who presented with atypical biochemical features of hyperammonaemia in addition to the classical presenting features of jaundice and lethargy after feeding. Red cell GALT activity was virtually absent in the patient while 50% of normal activity was found in parents and a sibling. Mutation screening excluded both Q188R and N314D as the causative mutation in GALT gene, which suggested a possible genetic segregation among ethnic groups. Data from a Taiwan screening program suggested that the incidence of the disease was approximately 1 in 400 000 in the Chinese population which was a sixth of that in Caucasian populations.
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Affiliation(s)
- K L Cheung
- Departments of Pediatrics and,Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong,,Institutes of Genetics, National Yang-Ming University, Taiwan, and Department of Medical Research and Education, Veterans General Hospital - Taipei, Taiwan,,Department of Pediatrics, British Columbia's Children's Hospital, Vancouver, BC, Canada
| | - Nls Tang
- Departments of Pediatrics and,Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong,,Institutes of Genetics, National Yang-Ming University, Taiwan, and Department of Medical Research and Education, Veterans General Hospital - Taipei, Taiwan,,Department of Pediatrics, British Columbia's Children's Hospital, Vancouver, BC, Canada
| | - K J Hsiao
- Departments of Pediatrics and,Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong,,Institutes of Genetics, National Yang-Ming University, Taiwan, and Department of Medical Research and Education, Veterans General Hospital - Taipei, Taiwan,,Department of Pediatrics, British Columbia's Children's Hospital, Vancouver, BC, Canada
| | - L K Law
- Departments of Pediatrics and,Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong,,Institutes of Genetics, National Yang-Ming University, Taiwan, and Department of Medical Research and Education, Veterans General Hospital - Taipei, Taiwan,,Department of Pediatrics, British Columbia's Children's Hospital, Vancouver, BC, Canada
| | - W Wong
- Departments of Pediatrics and,Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong,,Institutes of Genetics, National Yang-Ming University, Taiwan, and Department of Medical Research and Education, Veterans General Hospital - Taipei, Taiwan,,Department of Pediatrics, British Columbia's Children's Hospital, Vancouver, BC, Canada
| | - P C Ng
- Departments of Pediatrics and,Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong,,Institutes of Genetics, National Yang-Ming University, Taiwan, and Department of Medical Research and Education, Veterans General Hospital - Taipei, Taiwan,,Department of Pediatrics, British Columbia's Children's Hospital, Vancouver, BC, Canada
| | - C P Pang
- Departments of Pediatrics and,Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong,,Institutes of Genetics, National Yang-Ming University, Taiwan, and Department of Medical Research and Education, Veterans General Hospital - Taipei, Taiwan,,Department of Pediatrics, British Columbia's Children's Hospital, Vancouver, BC, Canada
| | - D A Applegarth
- Departments of Pediatrics and,Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong,,Institutes of Genetics, National Yang-Ming University, Taiwan, and Department of Medical Research and Education, Veterans General Hospital - Taipei, Taiwan,,Department of Pediatrics, British Columbia's Children's Hospital, Vancouver, BC, Canada
| | - T F Fok
- Departments of Pediatrics and,Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong,,Institutes of Genetics, National Yang-Ming University, Taiwan, and Department of Medical Research and Education, Veterans General Hospital - Taipei, Taiwan,,Department of Pediatrics, British Columbia's Children's Hospital, Vancouver, BC, Canada
| | - N M Hjelm
- Departments of Pediatrics and,Chemical Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong,,Institutes of Genetics, National Yang-Ming University, Taiwan, and Department of Medical Research and Education, Veterans General Hospital - Taipei, Taiwan,,Department of Pediatrics, British Columbia's Children's Hospital, Vancouver, BC, Canada
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17
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Cheung KL, Tang NL, Hsiao KJ, Law LK, Wong W, Ng PC, Pang CP, Applegarth DA, Fok TF, Hjelm NM. Classical galactosaemia in Chinese: A case report and review of disease incidence. J Paediatr Child Health 1999; 35:399-400. [PMID: 10457302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
We report a case of galactose-1-phosphate uridyl transferase (GALT) deficiency in a full-term Chinese neonate, who presented with atypical biochemical features of hyperammonaemia in addition to the classical presenting features of jaundice and lethargy after feeding. Red cell GALT activity was virtually absent in the patient while 50% of normal activity was found in parents and a sibling. Mutation screening excluded both Q188R and N314D as the causative mutation in GALT gene, which suggested a possible genetic segregation among ethnic groups. Data from a Taiwan screening program suggested that the incidence of the disease was approximately 1 in 400 000 in the Chinese population which was a sixth of that in Caucasian populations.
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Affiliation(s)
- K L Cheung
- Department of Pediatrics, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong
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18
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Tang NL, Pang CP, Yeo W, Choy KW, Lam PK, Suen M, Law LK, King WW, Johnson P, Hjelm M. Prevalence of mutations in the BRCA1 gene among Chinese patients with breast cancer. J Natl Cancer Inst 1999; 91:882-5. [PMID: 10340909 DOI: 10.1093/jnci/91.10.882] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- N L Tang
- Department of Chemical Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong Special Administrative Region.
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Wan DC, Law LK, Ip DT, Cheung WT, Ho WK, Tsim KW, Kay R, Woo J, Pang CP. Lack of allelic association of dopamine D4 receptor gene polymorphisms with Parkinson's disease in a Chinese population. Mov Disord 1999; 14:225-9. [PMID: 10091613 DOI: 10.1002/1531-8257(199903)14:2<225::aid-mds1004>3.0.co;2-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Parkinson's disease (PD) is a neurodegenerative disease caused by a multitude of environmental, neurochemical, and genetic factors. The gene for human dopamine D4 receptor (DRD4) has been considered as a plausible candidate for the pathogenesis of PD. Different dopamine D4 receptor allelic forms have variable affinity toward certain neuroleptics such as clozapine, suggesting a role for dopamine D4 receptors in neurologic disorders. To test the hypothesis that the DRD4 polymorphism is associated with the susceptibility to Parkinson's disease, we have examined differences in allele frequencies of different DRD4 polymorphisms in 101 Chinese patients with PD and in 105 age-matched control subjects in Hong Kong. The DRD4 gene was analyzed by a non-radioactive polymerase chain reaction-based Southern hybridization with chemiluminescence detection. The number of polymorphic 48 base pair tandem repeats in exon 3 was identified in each study subject. The DRD4 alleles with high frequencies in the control subjects are 4-repeat allele (72.4%), 2-repeat allele (21.4%), and 7-repeat allele (3.8%) which accounted for over 97% of the total alleles in the elderly Chinese population. The most prevalent genotype in the control subjects is the 4/4 (47.6%), followed by 4/2 (38.6), 4/7 (7.6%), and 2/2 (3.0%). None of the variable number tandem repeat polymorphism showed evidence for genetic association with Parkinson's disease.
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Affiliation(s)
- D C Wan
- Department of Biochemistry, The Chinese University of Hong Kong, Shatin, NT
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20
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Lai WK, Pang CP, Law LK, Wong R, Li CK, Yuen PM. Routine analysis of plasma busulfan by gas chromatography-mass fragmentography. Clin Chem 1998; 44:2506-10. [PMID: 9836718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Busulfan (BU) is a widely used alkylating agent for antineoplastic therapy and marrow ablation in preparation for bone marrow transplantation (BMT). High-dose BU often leads to successful preparation and low relapse but is associated with veno-occlusive disease of liver. We established a protocol to determine postdosage plasma BU concentrations by gas chromatography-mass fragmentography in an attempt to relate clinical outcome to plasma BU concentrations. We used nonisotopic pusulfan as the internal standard. After extraction into ethyl acetate, BU and pusulfan were iodinated into 1, 4-diiodobutane and 1,5-diiodopentane, respectively. Gas chromatography-mass spectrometry (GC-MS) analysis was carried out on an Hewlett-Packard (HP) 5890II gas chromatograph with a 30-m 100% methyl silicon narrow bore, fused-silica capillary column interfaced with an HP 5970A mass spectrometer. Helium was the carrier gas. The sample molecules were identified by total ion monitoring and quantified by selective ion monitoring of m/z 183 and 197. The calibration curve was linear to 4 mg/L. The limit of quantification was 0.04 mg/L, and the analytical recovery was approximately 97%. The within-day and between-day imprecision (CV) was <6% and 9%, respectively. In a preliminary study of 12 children, the BU areas under the BU-time curve were 616-949 micromol. min/L after the first dose and 793-1143 micromol. min/L after the fifth dose. We conclude that the GC-MS procedure is suitable for routine analysis of plasma BU.
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Affiliation(s)
- W K Lai
- Department of Chemical Pathology, the Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, New Territories, Hong Kong
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21
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Chan DK, Woo J, Ho SC, Pang CP, Law LK, Ng PW, Hung WT, Kwok T, Hui E, Orr K, Leung MF, Kay R. Genetic and environmental risk factors for Parkinson's disease in a Chinese population. J Neurol Neurosurg Psychiatry 1998; 65:781-4. [PMID: 9810958 PMCID: PMC2170330 DOI: 10.1136/jnnp.65.5.781] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
An epidemiological study of the environmental and genetic factors as well as the possible interplay between them was conducted among 215 patients with Parkinson's disease and 313 controls in a Chinese population in Hong Kong. In univariate analysis, a regular tea drinking habit was found to be a protective factor, which had not been reported before. Smoking (a protective factor), family history, duration of pesticide exposure (in years) in farming and pesticide exposure during farming in women (both risk factors) have been reported previously. In multivariate analysis, current smoking reached borderline significance at the 5% level and the variables, years exposed to pesticides and family history were significant at the 10% level. By contrast with the common occurrence of polymorphism of the CYP2D6 gene (a gene involved with xenobiotic metabolism) in white people, it is very rare in China and is not thought to be a significant factor contributing to Parkinson's disease in Chinese people.
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Affiliation(s)
- D K Chan
- Department of Geriatric Medicine, Prince of Wales Hospital, Randwick, NSW, Australia
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22
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Abstract
BACKGROUND Low serum cobalamin levels are often found in apparently normal older subjects. A major worry of leaving cobalamin deficiency untreated is that it may lead to subtle deterioration in cognitive function. OBJECTIVES To investigate the effect of supplementation on the cognitive function of older people with cobalamin deficiency by a randomized trial. METHODS Fifty Chinese subjects more than 60 years old with serum cobalamin level < 120 pmol/l were randomized into supplement and control groups. Fasting serum methylmalonic acid levels (MMA) were measured. A battery of neuropsychological tests was administered. The supplement group received intramuscular cyanocobalamin injections, while the control group received no intervention. They were followed up at around 4 months. RESULTS 78% of the subjects had raised MMA, indicating metabolic cobalamin deficiency. Supplemented subjects improved in performance IQ, but the amount of improvement was not significantly more than that of control subjects. Moreover, the supplement group fared worse than the control group at follow-up in some motor function scores. Three out of seven demented subjects had improvement in Mini-Mental State Examination scores, but there was no consistent improvement in other neuropsychological scores. CONCLUSIONS This study suggested that cobalamin deficiency did not invariably cause cognitive impairment in older people. There remain the possibilities that cobalamin deficiency causes cognitive impairment or exacerbates coexisting dementia in some older people.
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Affiliation(s)
- T Kwok
- Department of Medicine, Chinese University of Hong Kong, Hong Kong.
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23
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Tang NL, Hui J, Law LK, To KF, Ruiter JP, IJlst L, Wanders RJ, Ho CS, Fok TF, Yuen PM, Hjelm NM. Primary plasmalemmal carnitine transporter defect manifested with dicarboxylic aciduria and impaired fatty acid oxidation. J Inherit Metab Dis 1998; 21:423-5. [PMID: 9700600 DOI: 10.1023/a:1005314910623] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- N L Tang
- Department of Chemical Pathology, Prince of Wales Hospital, Chinese University of Hong Kong
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24
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Pang CP, Zhang J, Woo J, Chan D, Law LK, Tong SF, Kwok T, Kay R. Rarity of debrisoquine hydroxylase gene polymorphism in Chinese patients with Parkinson's disease. Mov Disord 1998; 13:529-32. [PMID: 9613747 DOI: 10.1002/mds.870130324] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Impaired debrisoquine metabolism resulting from defects in the cytochrome P450 CYP2D6-debrisoquine hydroxylase gene has been shown to be associated with the development of Parkinson's disease (PD). We studied two polymorphisms in this gene in 207 Chinese PD patients and 227 control subjects by polymerase chain reaction and restriction analysis. The G to A substitution at position 1934 in the junction of intron 3/exon 4 was detected in one sporadic PD patient and two control subjects, all of whom were heterozygous. The single base deletion at position 2637 in exon 5 was not detected in any of the study subjects. Such rarity of CYP2D6 polymorphism indicates PD in the Chinese population is associated with some other gene defects.
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Affiliation(s)
- C P Pang
- Department of Chemical Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Shatin, N.T
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Leighton PW, Le Couteur DG, Pang CC, McCann SJ, Chan D, Law LK, Kay R, Pond SM, Woo J. The dopamine transporter gene and Parkinson's disease in a Chinese population. Neurology 1997; 49:1577-9. [PMID: 9409349 DOI: 10.1212/wnl.49.6.1577] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
We studied a variable number tandem repeat polymorphism within the dopamine transporter gene (DAT) for an association with Parkinson's disease in a Chinese population. Five alleles were detected, consisting of 6, 8, 9, 10, and 11 copies of the 40 base pair repeat sequence. The 10-copy allele was most common, accounting for 90% of alleles. There were no significant differences between the patients and the control subjects in the distribution frequencies of the alleles or genotypes. Therefore, this polymorphism is not associated with Parkinson's disease in Chinese populations.
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Affiliation(s)
- P W Leighton
- University of Queensland, Department of Medicine, Princess Alexandra Hospital, Woolloongabba, Australia
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Pang CP, Law LK, Mak YT, Shek CC, Cheung KL, Mak TW, Lam CW, Chan AY, Fok TF. Biochemical investigation of young hospitalized Chinese children: results over a 7-year period. Am J Med Genet 1997; 72:417-21. [PMID: 9375724 DOI: 10.1002/(sici)1096-8628(19971112)72:4<417::aid-ajmg9>3.0.co;2-n] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
During the seven years from January 1989 to December 1995, we investigated 2,269 Chinese infants and young children for metabolic disorders in Hong Kong. These young patients, all aged under 4 years and originated from southern China, were ill with no apparent cause and had clinical manifestations suggestive of inherited metabolic diseases. A spot urine and a plasma sample were obtained from each patient for biochemical analysis, including urinary organic acid identification and plasma amino acid analysis. Six cases of mucopolysaccharidosis, four multiple carboxylase deficiency, three 2-methylacetoacetyl CoA thiolase deficiency, two methymalonic aciduria, one glutaric aciduria type I, one glutaric aciduria type II, one a-oxoglutaric aciduria, and one case of orotic aciduria were detected. There were also single suspected cases of medium-chain acyl-CoA dehydrogenase deficiency and isovaleric aciduria. No primary amino acid disorder, such as phenylketouria and maple syrup urine disease, has been detected. Our results suggest that a different pattern of inherited metabolic diseases exists in the southern Chinese when compared with the Chinese in other regions of China.
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Affiliation(s)
- C P Pang
- Department of Chemical Pathology, Chinese University of Hong Kong, Shatin, N.T
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27
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Law LK, Lau CY, Pang CP, Lam WY, Sweetman L, Fok TF, Hjelm M. An unusual case of multiple carboxylase deficiency presenting as generalized pustular psoriasis in a Chinese boy. J Inherit Metab Dis 1997; 20:106-7. [PMID: 9061576 DOI: 10.1023/a:1005382112066] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- L K Law
- Department of Chemical Pathology, Chinese University of Hong Kong, Shatin, N.T. Hong Kong
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28
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Law LK, Pang CP, Cheung KL, Fok TF. Cord blood biochemistry and idiopathic neonatal jaundice. Clin Chem 1996; 42:1716-7. [PMID: 8855162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- L K Law
- Dept of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hosp., Shatin, N.T
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29
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Affiliation(s)
- L K Law
- Dept of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hosp., Shatin, N.T
| | - C P Pang
- Dept of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hosp., Shatin, N.T
| | - K L Cheung
- Dept of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hosp., Shatin, N.T
| | - T F Fok
- Dept of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hosp., Shatin, N.T
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Chan JC, Nicholls MG, Cheung CK, Law LK, Swaminathan R, Cockram CS. Factors determining the blood pressure response to enalapril and nifedipine in hypertension associated with NIDDM. Diabetes Care 1995; 18:1001-6. [PMID: 7555530 DOI: 10.2337/diacare.18.7.1001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To examine the factors that determine the blood pressure response to enalapril and nifedipine monotherapy in the treatment of hypertension associated with non-insulin-dependent diabetes mellitus (NIDDM). RESEARCH DESIGN AND METHODS After a 6-week placebo baseline period, 102 hypertensive NIDDM patients were randomly assigned, double-blindly, to treatment with nifedipine retard (slow release) (n = 52) or enalapril (n = 50). The daily dosage of enalapril was increased, if required, from 10 to 20 to 40 mg and that of nifedipine from 40 to 60 to 80 mg at 4-week intervals during the 12-week titration period. Blood pressure, 24-h urinary albumin excretion (UAE), biochemical data, and serum angiotensin-converting enzyme (ACE) activity were measured at weeks -6, -4, 0, 4, 8, and 12. At week 0, venous blood was also sampled for baseline plasma atrial natriuretic peptide, renin, aldosterone, and serum insulin concentrations. RESULTS At week 12, the mean daily dose of enalapril was 35 +/- 11.4 mg, and 27 (57%) patients were receiving the maximum daily dose of 40 mg. In the nifedipine group, the mean daily drug dose was 50 +/- 12.9 mg, and 4 (8%) were receiving the maximum daily dose of 80 mg. Despite a dose-dependent fall in the serum ACE activity in the enalapril group, the mean arterial pressure (MAP) was reduced by only 8 mmHg throughout the 12-week titration period compared to a decline of 15, 18, and 19 mmHg at weeks 0, 4, and 12, respectively, in the nifedipine group (P = 0.01 between groups). In the enalapril group, changes in MAP between weeks 0 and 12 correlated significantly with baseline plasma glucose (r = 0.45, P = 0.001) and aldosterone concentrations (r = -0.32, P = 0.02) and UAE (r = 0.3, P = 0.04). There was no statistically significant correlation between the changes in MAP and baseline plasma renin concentration. On multivariate analysis, the baseline renal function, glycemic control, and plasma aldosterone and serum insulin concentrations were all independently related to the changes in blood pressure in the enalapril-treated patients. No such statistical associations were observed in the nifedipine group. CONCLUSIONS In hypertensive NIDDM patients, the activity of the renin-angiotensin-aldosterone system, the level of serum insulin, glycemic control, renal function, and proteinuria may be important determinants of the blood pressure response to ACE inhibition. Good glycemic control may optimize the antihypertensive efficacy of concomitant ACE inhibitor therapy.
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Affiliation(s)
- J C Chan
- Department of Clinical Pharmacology, Chinese University of Hong Kong, Prince of Wales Hospital, Shatin
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31
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Chan JC, Cheung CK, Cockram CS, Critchley JA, Swaminathan R, Law LK, Nicholls MG. Atrial natriuretic peptide and renin-angiotensin-aldosterone system in non-insulin-dependent diabetes mellitus. J Hum Hypertens 1994; 8:451-6. [PMID: 8089830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A total of 78 Chinese patients with clinically uncomplicated non-insulin-dependent diabetes (NIDDM) who had plasma creatinine concentrations of < 150 mumol/l were studied. Antihypertensive treatment was discontinued for at least six weeks prior to measurements of routine biochemistry, proteinuria, plasma atrial natriuretic peptide (ANP) concentrations and components of the renin-angiotensin-aldosterone system (RAAS). BP was measured on three occasions during the six weeks period prior to these measurements. At the end of the six week period, a total of 33 patients had definite hypertension (supine BP > or = 160/95 mmHg). The hypertensive patients had significantly higher plasma sodium (mean +/- SD): 140.3 +/- 1.9 vs. 138.5 +/- 2.0 mmol/l, P < 0.001) and lower plasma potassium (3.8 +/- 0.5 vs. 4.2 +/- 0.5 mmol/l, P < 0.01) concentrations. These were associated with reduced plasma aldosterone (median (range): 297 (98-1145) vs. 448.5 (93-1330) pmol/l, P < 0.01) and renin concentrations (16.8 (7.4-71.8) vs. 23.5 (7.4-83.7) ng/l, P = 0.06). The hypertensive patients also had significantly higher plasma ANP concentrations (36.5 (20.5-125.1) vs. 23.2 (11.7-63.0) pg/ml, P < 0.001), serum angiotensin converting enzyme (ACE) activity (65 (26-140.9) vs. 47 (22-106) units/l, P < 0.001) and urinary albumin excretion (UAE) (35.4 (1.6-4800) vs. 7.8 (1.8-310.4) mg/day, P < 0.001). Glycaemic control and renal function were similar between the two groups. Mean arterial pressure (MAP) correlated positively with plasma ANP concentration (r = 0.53, P < 0.001) and serum ACE activity (r = 0.37, P < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- J C Chan
- Department of Clinical Pharmacology, Prince of Wales Hospital, Chinese University of Hong Kong, Shatin
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Woo J, Ho SC, Mak YT, Law LK, Cheung A. Nutritional status of elderly patients during recovery from chest infection and the role of nutritional supplementation assessed by a prospective randomized single-blind trial. Age Ageing 1994; 23:40-8. [PMID: 8010171 DOI: 10.1093/ageing/23.1.40] [Citation(s) in RCA: 83] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
We examined changes in the nutritional status of elderly patients with chest infection for a period of 3 months after discharge from hospital, including the effects of nutritional supplementation on well-being and functional status as well as on nutritional indices. Eighty-one subjects admitted to an acute medical ward aged 65 years and over with chest infection were recruited consecutively, and randomized to receive supplement (500 ml of Ensure liquid daily) for 1 month, or no supplement, on discharge. Assessment at baseline, 1, 2 and 3 months included a questionnaire to determine health, mental and functional status, and anthropometric measurements. Biochemical nutritional status was assessed at baseline, 1 and 3 months, and dietary intake (24 h recall method) at 1 and 3 months. During recovery, both supplement and non-supplement groups showed improvement in various measures of well-being and biochemical status. In addition, the former group showed improvement in more anthropometric measurements, in thiamine and pyridoxine status, while the non-supplement group showed a lower level of functional ability after 3 months. Various measures of well-being and biochemical status of the water-soluble vitamins were better in the supplement groups. We conclude that nutritional supplementation may have a role in helping elderly patients to recover from chest infections.
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Affiliation(s)
- J Woo
- Department of Medicine, Chinese University, Hong Kong
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Law LK, Cheung CK, Swaminathan R. Possible interference by amiodarone and desethylamiodarone in thyroxin assays. Clin Chem 1988; 34:2154. [PMID: 3048786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- L K Law
- Dept. of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hospital, Shatin, NT
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34
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Law LK, Cheung CK, Swaminathan R. Possible interference by amiodarone and desethylamiodarone in thyroxin assays. Clin Chem 1988. [DOI: 10.1093/clinchem/34.10.2154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- L K Law
- Dept. of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hospital, Shatin, NT
| | - C K Cheung
- Dept. of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hospital, Shatin, NT
| | - R Swaminathan
- Dept. of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hospital, Shatin, NT
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35
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Law LK, Cheung CK, Swaminathan R. Falsely high thyroxin results by fluorescence polarization in sera with high background fluorescence. Clin Chem 1988; 34:1918. [PMID: 3416454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- L K Law
- Dept. of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hospital, Shatin, NT
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36
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Affiliation(s)
- L K Law
- Dept. of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hospital, Shatin, NT
| | - C K Cheung
- Dept. of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hospital, Shatin, NT
| | - R Swaminathan
- Dept. of Chem. Pathol., Chinese Univ. of Hong Kong, Prince of Wales Hospital, Shatin, NT
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Nobes DC, Villinger H, Davis EE, Law LK. Estimation of marine sediment bulk physical properties at depth from seafloor geophysical measurements. ACTA ACUST UNITED AC 1986. [DOI: 10.1029/jb091ib14p14033] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Abstract
When alpha- momorcharin was injected intraperitoneally (0.2 mg/25 g body weight) into pregnant mice on Days 1-3 of pregnancy, over 50% of the mice failed to support an implantation. In-vitro study of the effects of the protein on preimplantation embryos showed that the protein did not significantly disturb embryonic development from the 2-cell to compacting morula stage except when high concentrations (greater than or equal to 0.5 microgram/ml) of protein were present. In many embryos, compaction of blastomeres was incomplete and subsequent blastocyst formation was impaired. Other protein-treated embryos that formed compacted morulae and early blastocysts later showed decompaction and degenerated. The protein-treated embryos generally had fewer numbers of cells because cell division beyond the morula stage was impaired. The poor development of morulae may be the cause of inhibition of early pregnancy in the mouse by alpha- momorcharin .
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Law LK, Tam PP, Yeung HW. Effects of alpha-trichosanthin and alpha-momorcharin on the development of peri-implantation mouse embryos. J Reprod Fertil 1983; 69:597-604. [PMID: 6631823 DOI: 10.1530/jrf.0.0690597] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
alpha-Trichosanthin (0.3 mg/25 g) and alpha-momorcharin (0.2 mg/25 g) given intraperitoneally to mice on Days 4 and 6 of pregnancy led to an inhibition of implantation. In-vitro study of the effects of these proteins on developing mouse embryos showed that these proteins did not affect the transformation of morulae to blastocysts but further development was impaired: many blastocysts failed to hatch from the zona, the incidence of successful attachment to a plastic substrate decreased and the extent of trophoblastic outgrowth diminished. Inner cell mass development was less affected than was the trophoblast. The in-vivo inhibition of implantation may therefore be a consequence of the deleterious effect of these proteins on the trophoblast.
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Abstract
A crude methanol extract of the herb Davallina Orientalis was given intraperitoneally to test its effect on bone healing in mice. The results indicated that it could increase the breaking strength of a fracture site. In our experimental model, the lower dosage has a better result probably because of less toxicity.
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