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C K Lai

Publications and source records attributed to C K Lai.

At least 19 recordsLinked to original sources
PubMed2006

Drug-induced hypoglycaemia--new insight into an old problem.

OBJECTIVE: To review the causes of drug-induced hypoglycaemia in patients not taking hypoglycaemic medications. DESIGN: Retrospective study. SETTING: Regional hospitals in Hong Kong. PATIENTS: Patients with suspected drug-induced hypoglycaemia without a known history of exposure to hypoglycaemic agents, referred to the Hospital Authority Toxicology Reference Laboratory from June 2005 to March 2006 inclusive. MAIN OUTCOME MEASURES: Rate of positive cases, laboratory findings, possible causes, age distribution, and final outcomes. RESULTS: A total of 51 such patients were referred, in whom the presence of oral hypoglycaemic agents was detected (or inferred) in 23 (45%). In 12 of the 23 patients, oral hypoglycaemic agents could only be detected by target analysis, not through broad-spectrum screening. Gliclazide and glibenclamide were detected in 14 and eight patients respectively, whereas glimepiride, nateglinide and rosiglitazone were detected in the remaining patient. Possible sources of oral hypoglycaemic agents included drug administration errors in residential care homes for the elderly (n=9), mistakenly taking medication of a family member or employer (n=6), taking stock medication by mistake (n=2), taking Chinese proprietary medicine adulterated with oral hypoglycaemic agents (n=1), taking unknown pills bought from a retail pharmacy (n=1), and unknown (n=4). Regarding these 23 patients, 17 (74%) were aged 70 years or above and 21 (91%) recovered uneventfully. CONCLUSION: Hypoglycaemia due to inadvertent use of oral hypoglycaemic agents is a recognised problem, particularly in cases where family members living in the same household are taking similar medications. Possible drug administration errors in residential care homes for the elderly should be investigated, and procedures rectified if confirmed. Health care providers should be vigilant to such potential errors, especially in cases of unexplained hypoglycaemia.

Adult↗
PubMed2006

Acute renal failure associated with prolonged intake of slimming pills containing anthraquinones.

Chinese herbal medicine preparations are widely available and often regarded by the public as natural and safe remedies for a variety of medical conditions. Nephropathy caused by Chinese herbs has previously been reported, usually involving the use of aristolochic acids. We report a 23-year-old woman who developed acute renal failure following prolonged use of a proprietary Chinese herbal slimming pill that contained anthraquinone derivatives, extracted from Rhizoma Rhei (rhubarb). The renal injury was probably aggravated by the concomitant intake of a non-steroidal anti-inflammatory drug, diclofenac. Renal pathology was that of hypocellular interstitial fibrosis. Spontaneous renal recovery occurred upon cessation of the slimming pills, but mild interstitial fibrosis and tubular atrophy was still evident histologically 4 months later. Although a causal relationship between the use of an anthraquinone-containing herbal agent and renal injury remains to be proven, phytotherapy-associated interstitial nephropathy should be considered in patients who present with unexplained renal failure.

Acute Kidney Injury↗
PubMed2006

Aconite poisoning in camouflage.

The Toxicology Reference Laboratory has confirmed 10 cases of aconite poisoning from March 2004 to May 2006. In four of these 10 cases, the aconite herb was not listed in the written prescription. We report these four cases to highlight the problem of 'hidden' aconite poisoning.

Aconitum↗
PubMed2003

Juvenile-onset glycogen storage disease type II with novel mutations in acid alpha-glucosidase gene.

The authors describe two novel mutations of the acid alpha-glucosidase gene, P361L and R437C, which define the juvenile-onset glycogen storage disease type II (GSDII) in a 16-year-old Chinese patient. The asymptomatic 13-year-old brother of the proband is also a compound heterozygote of the two mutations. These results confirm that intrafamilial phenotypic variation of juvenile-onset GSDII is ethnically diverse and suggest the contribution of other genes to the phenotypic variability of GSDII.

Adolescent↗
PubMed2003

Diagnosis of dihydropyrimidine dehydrogenase deficiency in a neonate with thymine-uraciluria.

Dihydropyrimidine dehydrogenase deficiency is an inborn error of pyrimidine metabolism characterised by thymine-uraciluria, convulsive disorders and developmental delay in paediatric patients, and an increased risk of toxicity from 5-fluorouracil treatment. This report is of the first patient with dihydropyrimidine dehydrogenase deficiency diagnosed in Hong Kong. The patient was a 2-day-old male neonate of Pakistani origin who presented with convulsions. Diagnosis was made by gas chromatographic-mass spectrometric detection of thymine-uraciluria and by molecular detection of a G to A point mutation in a 5'-splicing site leading to skipping of exon 14 in the DPYD gene of chromosome location 1q22. The results showed that the patient and his mother were homozygous and the father heterozygous for the splice site mutation. The mother also had thymine-uraciluria but was clinically asymptomatic.

Dihydrouracil Dehydrogenase (NADP)↗
PubMed2002

Snoezelen for dementia.

BACKGROUND: Snoezelen, multi-sensory stimulation, provides sensory stimuli to stimulate the primary senses of sight, hearing, touch, taste and smell, through the use of lighting effects, tactile surfaces, meditative music and the odour of relaxing essential oils (Pinkney 1997). The clinical application of snoezelen has been extended from the field of learning disability to dementia care over the past decade. The rationale for its use lies in providing a sensory environment that places fewer demands on intellectual abilities but capitalizes on the residual sensorimotor abilities of people with dementia (e.g. Buettner 1999, Hope 1998). Practitioners are keen to use snoezelen in dementia care, and some encouraging results have been documented in the area of promoting adaptive behaviours (e.g. Baker, Long 1992, Spaull 1998). However, the clinical application of snoezelen often varies in form, nature, principles and procedures. Such variations not only make examination of the therapeutic values of Snoezelen difficult, but also impede the clinical development of snoezelen in dementia care. A systematic review of evidence for the efficacy of snoezelen in the care of people with dementia is therefore needed to inform future clinical applications and research directions. OBJECTIVES: This review aims to examine the clinical efficacy of snoezelen for older people with dementia. SEARCH STRATEGY: "Snoezelen", "multi-sensory", "dement*", "Alzheimer*", "randomized control/single control/double control" were used as keywords to search seven electronic databases (e.g. MEDLINE, PsyLIT). The list of trials was compared with those identified from a search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group. SELECTION CRITERIA: All RCTs in which Snoezelen or multi-sensory programmes were used as an intervention for people with dementia were included in the review. Trial data included in the review were restricted to those involving people aged over 60 years suffering from any type of dementia, except one subject of Baker's study was aged below 60 years. DATA COLLECTION AND ANALYSIS: Only two RCTs fulfill the inclusion criteria for this systematic review. Two reviewers independently extracted the data from these two inclusion studies. Quantitative synthesis of the comparable data from the two trials was performed. MAIN RESULTS: Two trials were included. Both Baker (and Kragt examined the short-term values of snoezelen on the behaviours of people with dementia. Although the pooled results were insignificant, the trend was in the direction of favouring treatment (hence a negative value of the SMD). The standardized mean difference (SMD) was -1.22, with a 95% confidence interval (CI) (-4.08, 1.64). Kragt's result, weighted 47%, was significant in favour of treatment, with a SMD of -2.77 and a 95% CI (-4.24, -1.29). During the snoezelen session, Kragt's subjects presented significantly fewer apathetic behaviours (t=-8.22, p<0.01), fewer restless behaviours (t=-3.00, p=0.01), fewer repetitive behaviours (t=-.822, p<0.01), and fewer disturbances (t=-4.91, p<0.01). Baker's result was slightly not in favour of the treatment, with a SMD of 0.16 and a 95% CI (-0.41, 0.73). The control subjects touched objects/equipment more appropriately within the activity sessions than the subjects who participated in snoezelen sessions (F(1,47)=5.96, p=.001). Kragt did not examine the carryover and long-term effects of snoezelen, so only Baker's results were analysed. Baker used the Behavioural and Mood Disturbance scale (BMD), the REHAB, the CAPE and MMSE to assess patients mood, behaviour and cognition after (but not immediately after) four treatment sessions and eight treatment sessions. Some assessments were carried at home, some at day hospital. There were many subscores and mostly there were no differences between treatment and control. The following significant differences were found with benefit in favour of snoezelen compared with control after four sessions: apathy ezelen compared with control after four sessions: apathy score of the BRS (CAPE) (MD -3.00, 95%CIs -5.87 to -0.13, P=0.04), after eight sessions: mood score of the BRS (CAPE) (MD -2.60, 95%CIs -4.92 to -0.28, P=0.03), total score of the BRS (CAPE) (MD -6.92, 95%CIs -13.13 to -0.7, P=0.03), speech skills of the REHAB (MD 1.46, 95%CIs 0.01 to 2.82, P=0.03), psychomotor subscore of the cognitive assessment scale of CAPE (MD -3.12, 95%CIs -5.31 to -0.93, P<0.01). REVIEWER'S CONCLUSIONS: Two trials were reviewed. Although both studies examined the short-term values of snoezelen on people with dementia, it is not feasible to draw a firm conclusion at this stage, for two main reasons. Firstly, very limited data were available for analysis, thus limiting data inference and generalization. Secondly, different methodology and control conditions were adopted in the two trials. Such variations not only require a careful interpretation of results but also make the comparison of results across studies less valid. Hence, there is an urgent need for more systematic and scientific research studies to examine the clinical value of snoezelen for people with dementia. To our knowledge, there are four RCTs currently in progress. It is hoped that the data and results of these trials will enrich the systematic review of snoezelen for dementia in the next update.

Aged↗
PubMed2002

Infantile isolated sulphite oxidase deficiency in a Chinese family: a rare neurodegenerative disorder.

We report the clinical, biochemical, neuroradiological, and neurophysiological findings of a 4-year-old Chinese girl with infantile isolated sulphite oxidase deficiency. This is the first reported case in our locality. She presented at the age of 5 months with refractory seizures and developmental regression, and progressed rapidly to profound psychomotor retardation, spasticity, dystonia, microcephaly, and blindness. At the age of 3.5 years, she was admitted to the intensive care unit with septic shock. Ophthalmologic examination at this time revealed bilateral dislocation of the lens. Diagnosis of this very rare disorder was made on the basis of increased levels of urinary sulphite, thiosulphate, and sulphocysteine; normal urine xanthine and hypoxanthine; normal plasma uric acid; and low plasma cystine levels. The diagnosis was confirmed by the absence of sulphite oxidase activities in skin fibroblasts. Isolated sulphite oxidase deficiency is a rare inborn error of sulphur metabolism that is difficult to diagnose on clinical features and routine metabolic tests. The presence of ectopia lentis, seizures, and progressive neurological abnormalities should alert clinicians to the diagnosis.

Amino Acid Metabolism, Inborn Errors↗
PubMed2001

Transcription repression of human hepatitis B virus genes by negative regulatory element-binding protein/SON.

A negative regulatory element (NRE) is located immediately upstream of the upstream regulatory sequence of core promoter and second enhancer of human hepatitis B virus (HBV). NRE represses the transcription activation function of the upstream regulatory sequence of core promoter and the second enhancer. In this study, we described the cloning and characterization of an NRE-binding protein (NREBP) through expression cloning. NREBP cDNA is 8266 nucleotides in size and encodes a protein of 2386 amino acids with a predicted molecular mass of 262 kDa. Three previously described cDNAs, DBP-5, SONB, and SONA, are partial sequence and/or alternatively spliced forms of NREBP. The genomic locus of the NREBP/SON gene is composed of 13 exons and 12 introns. The endogenous NREBP protein is localized in the nucleus of human hepatoma HuH-7 cells. Antibody against NREBP protein can specifically block the NRE binding activity present in fractionated nuclear extracts in gel shifting assays, indicating that NREBP is the endogenous nuclear protein that binds to NRE sequence. By polymerase chain reaction-assisted binding site selection assay, we determined that the consensus sequence for NREBP binding is GA(G/T)AN(C/G)(A/G)CC. Overexpression of NREBP enhances the repression of the HBV core promoter activity via NRE. Overexpression of NREBP can also repress the transcription of HBV genes and the production of HBV virions in a transient transfection system that mimics the viral infection in vivo.

Base Sequence↗
PubMed2001

Absorption of lidocaine during aspiration anesthesia of the airway.

STUDY OBJECTIVE: To determine the optimal solution to use when anesthetizing the airway by aspiration of lidocaine. DESIGN: Randomized, double-blind clinical study. SETTING: University hospital. PATIENTS: 96 adult ASA physical status 1,II, and III patients, scheduled for diagnostic flexible bronchoscopy. INTERVENTIONS: Patients were randomized to receive one of 5 solutions of lidocaine: Group A (n = 16): 1% lidocaine, 0.2 mL. kg(-1); Group B (n = 16): 1.5% 0.2 mL. kg(-1); Group C (n = 32): 2% 0.2 mL. kg(-1); Group D (n = 16): 1% 0.3 mL. kg(-1), and Group E (n = 16): 2% 0.3 mL. kg(-1). Fiberoptic bronchoscopy was performed after the airway was anesthetized with this aspiration technique, using the assigned lidocaine solution. The scope was manipulated in the trachea to test for anesthesia. MEASUREMENTS AND MAIN RESULTS: Successful airway anesthesia was determined by tolerance to bronchoscopy without sustained coughing, and also by the number of lidocaine supplements, if any, that were given via the bronchoscope. Arterial plasma concentrations of lidocaine were measured in 33 patients from Groups C, D, and E. All solutions provided equally effective anesthesia of the airway. All patients tolerated endoscopy through the vocal cords, and 94 patients required no supplementary anesthesia, or only one dose of lidocaine, during bronchoscopy to the carina. The highest peak plasma concentrations of lidocaine were 5.02 and 6.28 microg. mL. No patient had signs of toxicity. CONCLUSIONS: This technique produced anesthesia of the airway to the carina, safely, suitable for awake intubation, in 94 of 95 patients. The use of 1% lidocaine, 0.2 to 0.3 mL. kg(-1), so that the volume is 10 to 20 mL, is recommended.

Absorption↗
PubMed2001

Temporal relationship between air pollution and hospital admissions for asthmatic children in Hong Kong.

BACKGROUND: Many epidemiological studies have shown positive association between respiratory health and current levels of outdoor air pollution in Europe and America. OBJECTIVE: The aim of this study was to investigate the association between air pollution and the number of childhood admissions for asthma in Hong Kong. METHODS: Daily counts of childhood admission for asthma to a large teaching Hospital were obtained from the computerized database for the period 1993-1994. A Poisson regression allowing for seasonal patterns and meteorological conditions was used to assess the associations between the number of Hospital admissions and the three pollutants: nitrogen dioxide, sulphur dioxide and inhalable particles (measured as PM10, particles < 10 microm in aerodynamic diameter). RESULTS: A total of 1217 children under 15 years of age were admitted for asthma during the study period. The calculated annual hospitalization rates were 283 and 178 per 100 000 for boys and girls, respectively. The mean PM10, NO2 and SO2 levels were 44.1 microg/m3, 43.3 microg/m3, and 12.2 microg/m3, respectively. Daily admission for asthma increased significantly with increasing ambient level of nitrogen dioxide (relative risk (RR) = 1.08 per 10 microg/m3 increase), sulphur dioxide (RR = 1.06) and inhalable particles (RR = 1.03). No association was found between hospital admission and humidity, temperature or atmospheric pressure. CONCLUSION: This is the first daily time series study of childhood admissions for asthma and air pollution in Hong Kong. The results support that current levels of air pollution contribute to the respiratory morbidity in asthmatic children in Hong Kong.

Adolescent↗
PubMed2001

Validation of the Chinese translated version of ISAAC core questions for atopic eczema.

BACKGROUND: The International Study of Asthma and Allergies in Childhood (ISAAC) was designed to allow international comparison of epidemiological data on atopic conditions in childhood. In so doing, further aetiological information would be obtained that in turn would provide a framework for future studies. The global ISAAC results on the prevalence of atopic dermatitis indicated a 60-fold variation recorded in different countries. Such a degree of difference may be partially due to the translated questionnaires that were not validated in all of the involved countries. OBJECTIVE: To validate the Chinese version of the ISAAC core questions for atopic eczema. METHODS: One thousand nine hundred and twenty children aged between 3 and 5 were randomly recruited from 13 kindergartens in Hong Kong. Using a dermatologist's clinical examination as the gold standard, we validated the Chinese version of the ISAAC core questions for atopic eczema. The Youden's Indexes obtained in our study were compared with those obtained in the United Kingdom's validation study. RESULTS: The Youden's Indexes obtained in our study were significantly lower than those from the United Kingdom. The low scores were likely to be due to a reduction in the sensitivity of the Chinese questionnaire, which ranged from 23.5% to 70.6%. CONCLUSION: Our findings indicate that the translated questionnaire is less effective than the English version in assessing the prevalence of atopic eczema. The indication of a low prevalence of atopic eczema among the Chinese population reported in previous studies was at least partially due to problems with the translated questionnaire.

Child, Preschool↗
PubMed2001

Prevalence of respiratory and atopic disorders in Chinese schoolchildren.

BACKGROUND: Epidemiological surveys have shown that the prevalence of asthma in the Asian population is relatively low. Within the Chinese population, schoolchildren from Hong Kong were found to have the highest rate of asthma. OBJECTIVE: To compare the prevalence of respiratory and atopic disorders, and to assess the role of atopy in the development of asthma, in Chinese schoolchildren from Hong Kong, Beijing and Guangzhou. METHODS: Community-based random samples of schoolchildren aged 9-11 years from three Chinese cities (Hong Kong, Beijing and Guangzhou) were recruited for study using the International Study of Asthma and Allergies in Childhood (ISAAC) Phase II protocol. Subjects were studied by parental questionnaires (n = 10902), skin-prick tests (n = 3479) and skin examination (n = 3479). RESULTS: The prevalence rates of current wheeze, speech limiting wheeze, rhinoconjunctivitis and flexural dermatitis were significantly more common in Hong Kong than in Beijing or Guangzhou. The atopy rate was also higher in Hong Kong (41.2%) than in Beijing (23.9%) or Guangzhou (30.8%). Atopy was strongly correlated with current wheeze (OR 7.74; 95% CI = 5.70-10.51). Subgroup analyses of children from Hong Kong revealed that children born in mainland China who had subsequently migrated to Hong Kong had a significantly lower rate of allergic symptoms and atopy than those children born in Hong Kong. CONCLUSION: Using a standardized written questionnaire along with a skin prick test and skin examination, we confirmed that the prevalence of asthma, allergic diseases and atopy was highest in schoolchildren from Hong Kong. Atopic sensitization is an important factor associated with asthma in Chinese children.

Asian People↗
PubMed2001

Novel mutation in the GRHPR gene in a Chinese patient with primary hyperoxaluria type 2 requiring renal transplantation from a living related donor.

We identified a patient with primary hyperoxaluria type 2 (PH2) showing recurrent stone formation, nephrocalcinosis, end-stage renal failure, and rapid oxalate deposition after renal transplantation from a living related donor. Urinary organic acid analysis performed after renal transplantation confirmed the diagnosis of PH2. We analyzed the glyoxylate reductase/hydroxypyruvate reductase (GRHPR) gene of the patient. DNA sequencing of all nine exons and exon-intron boundaries showed a novel homozygous mutation deleting the last two nucleotides of exon 8, ie, 862delTG. This deletion results in a frameshift and introduction of a premature stop codon at codon 310, ie, Ala310Stop. One of the patient's sisters is heterozygous for this mutation, and the other sister, who is the donor, does not have this mutation. The rapid deposition of oxalate in the transplanted kidney indicates that the kidney is not a major site of oxalate production. The more favorable long-term prognosis of PH2 needs to be reevaluated now that the molecular basis of PH2 has been established. DNA-based diagnosis will facilitate carrier detection, prenatal diagnosis, genetic counseling, and selection of living related donors.

Adolescent↗
PubMed2001

RNA binding domain of telomerase reverse transcriptase.

Telomerase is a ribonucleoprotein reverse transcriptase that extends the ends of chromosomes. The two telomerase subunits essential for catalysis in vitro are the telomerase reverse transcriptase (TERT) and the telomerase RNA. Using truncations and site-specific mutations, we identified sequence elements of TERT and telomerase RNA required for catalytic activity and protein-RNA interaction for Tetrahymena thermophila telomerase. We found that the TERT amino and carboxyl termini, although evolutionarily poorly conserved, are nonetheless important for catalytic activity. In contrast, high-affinity telomerase RNA binding requires only a small region in the amino terminus of TERT. Surprisingly, the TERT region necessary and sufficient for telomerase RNA binding is completely separable from the reverse transcriptase motifs. The minimal Tetrahymena TERT RNA binding domain contains two sequence motifs with ciliate-specific conservation and one TERT motif with conservation across all species. With human TERT, we demonstrate that a similar region within the TERT amino terminus is essential for human telomerase RNA binding as well. Finally, we defined the Tetrahymena telomerase RNA sequences that are essential for TERT interaction. We found that a four-nucleotide region 5' of the template is critical for TERT binding and that the 5' end of telomerase RNA is sufficient for TERT binding. Our results reveal at least one evolutionarily conserved molecular mechanism by which the telomerase reverse transcriptase is functionally specialized for obligate use of an internal RNA template.

Animals↗
PubMed2001

Asthma, atopy and tuberculin responses in Chinese schoolchildren in Hong Kong.

BACKGROUND: The prevalence rates of asthma and other atopic disorders have increased steadily in many developed countries over the past few decades. Recent epidemiological and animal studies have suggested that BCG vaccination might be beneficial in reducing the subsequent development of atopy. This study investigates the relationship between asthma, allergic symptoms, atopy, and tuberculin response in Chinese schoolchildren who received BCG vaccination at birth. METHODS: A total of 3110 schoolchildren aged 10 years were recruited for the Hong Kong arm of the phase II International Study of Asthma and Allergies in Childhood. Of the 2599 children born in Hong Kong and vaccinated with BCG after birth, 2201 had tuberculin testing performed at a mean (SD) age of 8.4 (1.4) years. A random subsample of 980 children was also recruited for skin prick testing. RESULTS: The prevalence rates of asthma ever, wheeze ever, current wheeze, current rhinoconjunctivitis, and current flexural eczema were not significantly different between tuberculin positive and negative subjects. The mean (SE) tuberculin response was 3.4 (0.2) mm in atopic subjects and 3.3 (0.2) mm in non-atopic subjects (difference not significant). Logistic regression analyses did not reveal any significant relationship between asthma ever, current wheeze, atopy, and positive tuberculin responses. CONCLUSIONS: This study did not find any relationship between asthma, allergic symptoms, atopy, and positive tuberculin reactivity in Chinese schoolchildren vaccinated with BCG at birth.

Asthma↗
PubMed2001

Determinants of continuous positive airway pressure compliance in a group of Chinese patients with obstructive sleep apnea.

OBJECTIVE: To assess continuous positive airway pressure (CPAP) compliance and factors associated with CPAP compliance among Chinese patients with obstructive sleep apnea (OSA). DESIGN: A prospective study of 112 consecutive patients with newly diagnosed OSA commencing CPAP treatment. SETTING: A university teaching hospital. MEASUREMENTS AND RESULTS: The following factors were evaluated for any correlation with objective CPAP compliance (effective mask pressure [hours per day]) at 1 month and 3 months: age, baseline apnea-hypopnea index (AHI), common OSA symptoms, minimum arterial oxygen saturation (SaO(2)), mean SaO(2), arousal index (AI), Epworth sleepiness scale (ESS), education level, CPAP levels, satisfaction with CPAP, side effects, and machine cost. There were 101 male and 11 female patients, with a mean (+/- SD) age of 45.6 +/- 1.2 years; body mass index, 29.3 +/- 5.2 kg/m(2); AI, 60 +/- 18/h; AHI, 48 +/- 24/h; minimum SaO(2) of 70 +/- 17%; and mean SaO(2) of 86 +/- 7%. ESS fell from 12.9 +/- 4.0 (baseline) to 5.2 +/- 4.7 at 3 months (p < 0.001). Objective CPAP compliance was 5.4 +/- 1.6 h/d and 5.3 +/- 1.6 h/d, while 75% and 72% of our patients were using CPAP objectively for > or = 4 h/d and at least 70% of the nights per week at 1 month and 3 months, respectively. Following univariate analysis of variance, a high baseline AHI (p = 0.006 and p = 0.004) was associated with higher objective CPAP compliance at 1 month and 3 months, respectively. CONCLUSION: CPAP usage and compliance were high in this patient population. A high baseline AHI was the only significant independent predictor of better CPAP compliance.

Age Factors↗