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Biomedical subjects

Y H Chan

Publications and source records attributed to Y H Chan.

At least 73 records · Page 4Linked to original sources
PubMed2002

Milk supplementation prevents bone loss in postmenopausal Chinese women over 3 years.

Previously published results from a 2 year randomized, controlled clinical trial on supplementing the diet of postmenopausal Chinese women with high-calcium milk powder (containing 800 mg of calcium) showed that bone loss, as measured by bone mineral density (BMD), was prevented. To determine whether the effect of calcium supplementation could be sustained, the study was extended for 1 additional year. According to the intention-to-treat analysis, the differences in the rate of bone loss (percentage decrease in control group--percentage decrease in milk supplementation group) in the third year of the study were: total body BMD, 0.23% (95% confidence interval [CI] 0.07%-0.39%); total spine BMD, 0.31% (95% CI - 0.02%-0.65%); and total hip BMD, 0.44% (95% CI 0.19%-0.69%). Analysis by the per-protocol method showed a similar effect size. These results indicate that the effects of milk supplementation in preventing bone loss in postmenopausal Chinese women were sustained after 2 years.

Animals↗
PubMed2002

Clinical characteristics of pruritus in chronic idiopathic urticaria.

BACKGROUND: Although pruritus is a predominant symptom of chronic idiopathic urticaria (CIU) its clinical characteristics have not been explored. OBJECTIVES: To characterize the clinical pattern and sensory and affective dimensions of the itch experience, utilizing a comprehensive itch questionnaire. METHODS: A structured questionnaire based on the McGill pain questionnaire was used in 100 patients suffering from CIU randomly recruited from a tertiary referral centre. RESULTS: All 100 patients recruited with CIU completed the questionnaire. In 68 patients pruritus appeared on a daily basis. Most patients experienced their pruritus at night and in the evening (n = 83), and 62 reported difficulty in falling asleep. Pruritus involved all body areas, but mostly the arms (n = 86), back (n = 78) and legs (n = 75). Accompanying symptoms were a sensation of heat in 45 patients and sweating in 15. Most patients (n = 98) were prescribed antihistamines (mainly sedating), of whom 34 experienced long-term relief. The sensation of itch was reported to be stinging (n = 27), tickling (n = 25) and burning (n = 23). Seventy-six patients found their pruritus bothersome, 66 annoying and 14 complained of depression. The itch intensity at its peak was more than double that felt after a mosquito bite. The worst itch scores of those who felt depressed were significantly higher than of those who did not (P = 0.018). There was a positive correlation between the sensory and affective scores during worst itch (P < 0.001). CONCLUSIONS: This study describes the itch experienced in CIU, highlighting sensory and affective dimensions. The itch questionnaire was found to be a valuable tool for evaluating pruritus in CIU and its unique features.

Activities of Daily Living↗
PubMed2002

Itch characteristics in Chinese patients with atopic dermatitis using a new questionnaire for the assessment of pruritus.

BACKGROUND: Although pruritus is the predominant and commonest feature of atopic dermatitis, its clinical characteristics have not been explored. OBJECTIVE: To characterize the clinical pattern and sensory and affective dimensions of the itch experience utilizing a comprehensive itch questionnaire. METHODS: A structured itch questionnaire based on the McGill pain questionnaire was given to 102 Chinese patients with known atopic dermatitis. RESULTS: There were 100 patients with atopic dermatitis who fully filled the questionnaire. In 87% of the patients pruritus appeared on a daily basis. It had a prolonged duration (mean duration 10.7 7.3 years). It involved all body areas mostly in the lower limbs (83%), flexures (76%), upper limbs (71%) and neck (65%). Itch intensity during its peak was nearly twice higher than the itch of a mosquito bite. Itching was most frequent at night (65%), and 84% of patients reported of difficulty falling asleep. Daily life activities which increased the severity of itch were sweat in 96%, dryness in 71%, stress in 71% and physical effort in 73%. The major factors which were found to reduce the intensity of pruritus included: bathing with cold water in 55% and cold ambient environment in 56%. Associated symptoms were heat sensation (51%), sweating (40%) and pain in the pruritic area (45%). The various anti-pruritic therapies had limited long-term effect. The pruritus was bothersome (52%) and a major distress to the patient. The affective score correlated to itch intensity during its peak (r = 0.4, P < 0.001). CONCLUSIONS: The study provided a detailed description of pruritus in atopic dermatitis with new data on affective and sensory dimensions and associated symptoms. The questionnaire was found to be a useful tool in characterization of itch.

Adolescent↗
PubMed2002

Use of hypoallergenic formula in the prevention of atopic disease among Asian children.

OBJECTIVE: To determine the effect of a partially hydrolysed formula on genetically predisposed children, with respect to the development of atopic clinical manifestations and in vitro testing of serum IgE levels (total and milk-specific). METHODS: One hundred and ten infants were randomly assigned to receive either partially hydrolysed formula or standard infant formula, and were prospectively monitored from birth for clinical atopic symptoms and serum IgE levels. RESULTS: Eczema occurred less frequently in infants receiving partially hydrolysed formula. This was significant (P < 0.05) at 3, 6, 9, 12, 18 and 24 months. However, the significance decreased with time, although it almost reached statistical significance at 30 months by the Kaplan-Meier survival function (log-rank statistic, 3.46; P = 0.063). Although wheezing occurred less frequently in infants receiving partially hydrolysed formula, compared to those receiving standard infant formula, the difference did not reach statistical significance (P > 0.05). CONCLUSIONS: Exclusive feeding of hypoallergenic milk formula in the first 4 months of life has a protective effect in terms of the development of atopic dermatitis in the first 2 years of life, compared to feeding with cow's milk formula.

Child↗
PubMed2002

Thyroid dysfunction in chronic schizophrenia within a state psychiatric hospital.

OBJECTIVES: This study seeks to determine the prevalence and pattern of thyroid dysfunction in a group of adult psychiatric inpatients with chronic schizophrenia. We also hypothesize that raised thyroid hormones are associated with more severe psychopathology. METHODS: Thyroid function tests were performed on 189 patients and the Brief Psychiatric Rating Scale (BPRS) was administered by a single rater on all patients. RESULTS: There was a high prevalence of (36.4%) thyroid function test abnormalities but all patients except 1 were assessed to be clinically euthyroid. Free thyroxine (fT4) and triiodothyronine (fT3) were significantly higher in patients with mild (BPRS score, 10-20) and major syndrome (BPRS score, equal or above 21) compared to no syndrome (BPRS score, 0-9). No correlation was found between thyroid hormones and neuroleptic use. CONCLUSION: Although thyroid function test abnormalities are common in patients with chronic schizophrenia, clinical thyroid illness was absent. This calls for caution in the use and interpretation of thyroid function tests in patients with chronic schizophrenia.

Adult↗
PubMed2002

Early unplanned readmission of elderly in Singapore: a retrospective study.

STUDY OBJECTIVE: To study the incidence and profile of elderly patients requiring early unplanned readmission within 15 days of discharge from a regional hospital and the predictive factors for readmission. PATIENTS: All patients (n = 150) aged 65 years old and above who were readmitted within 15 days into the hospital's geriatric unit in the western region of Singapore over a period of 10 months were retrospectively studied. METHODOLOGY: Demographic data, information on patients' medical problems and social environment were gathered from the patients' medical, nursing and therapist records. A control group (n = 103) consisting of patients not readmitted over 15 days were gathered over the same period. RESULTS: The percentage of readmission over the period between 1 January 1999 and 31 October 1999 was (150/1632) 9.2% (95% CI, 7.8% to 10.7%). There were a total of 150 patients with an equal number of male and female patients. The patients had a mean of 4 medical problems. Cardiovascular disease was noted in 73% (95% CI, 65.5% to 80.2%) of the patients during the index admissions. They were noted to be ambulatory and were staying with their own families. Half of the patients were discharged from the index admission with no adjustment to their previous care system. The majority of patients (68.7%; 95% CI, 59.9% to 75.4%) required readmission because of medical problems. Fifty per cent of the patients admitted for a new medical complaint were secondary to sepsis. Thirty per cent (95% CI, 22.8% to 38.0%) of the study population had both medical and social issues. The main predictive factors noted when compared to a control group of 103 patients (using a stepwise logistic regression model) were number of medical problems (P = 0.0128; OR = 1.4; 95% CI, 1.1 to 1.9) and number of previous admissions (P = 0.005; OR = 1.6; 95% CI, 1.2 to 2.3). CONCLUSION: Unplanned readmissions are relatively common in elderly patients. They cannot be entirely prevented in view of multiple chronic illnesses. Further studies, looking at early detection of medical problems and prevention of nosocomial infections are warranted to decrease the problem of readmissions for this group of elderly.

Age Factors↗
PubMed2001

Molecular cloning of a teleost growth hormone receptor and its functional interaction with human growth hormone.

This paper reports the first full-length cDNA sequence of a growth hormone receptor (GHR) from a teleost fish and its functional expression in cultured eukaryotic cells. The cDNA sequence, from Carassius auratus (goldfish), encodes a protein of 602 amino acids (aa) akin in architecture to the GHRs of other species. Despite the presence of motifs characteristic of GHR, the overall homology between the goldfish GHR and other GHRs is very low ( approximately 40% aa identity). CHO cells transfected with this receptor cDNA can be stimulated to proliferate by human growth hormone (hGH). In addition, the transfected cells can transactivate a co-expressed mammalian serine protease inhibitor (Spi) 2.1 promoter upon stimulation by hGH, indicating the successful interaction of the fish receptor with the mammalian ligand to evoke the down-stream post-receptor events. Tissue distribution studies indicated that the receptor is mostly expressed in the liver and hypothalamus of goldfish. A single mRNA transcript of a size of about 4 kb was found in the goldfish liver.

Amino Acid Sequence↗
PubMed2001

Evaluating the role of alternative therapy in burn wound management: randomized trial comparing moist exposed burn ointment with conventional methods in the management of patients with second-degree burns.

CONTEXT: Moist exposed burn ointment (MEBO), from China, has been said to revolutionize burn management. OBJECTIVE: Our study was conducted to compare MEBO with conventional management (C) with respect to the rate of wound healing, antibacterial and analgesic effect, and hospital costs. DESIGN: This is a prospective, randomized, controlled clinical trial conducted between 1 March 1997 and 24 October 1998. SETTING: The trial was conducted in a specialized burn facility located in a tertiary referral hospital in a developed and industrialized island-state in Southeast Asia. PATIENTS: We randomly assigned 115 consecutive patients between the ages of 12 and 80 who had partial-thickness thermal burns covering less than 40% of body surface area (BSA) to receive either MEBO or C. Fifty-seven patients were assigned to MEBO and 58 patients to C. The latter group received twice-daily dressing changes; MEBO patients received MEBO every 4 hours. MAIN OUTCOME MEASURES: Patients were hospitalized until 75% BSA had healed. BSA was determined by visual inspection and charted on Lund and Browder charts regularly. Wound healing rate, bacterial infection rate, pain score, and hospitalization costs were recorded. RESULTS: The median time to 75% healing was 17.0 and 20.0 days with MEBO and C, respectively (HR = 0.67, 95% CI = 0.41-1.11, P =.11), suggesting similar efficacy between the 2 modalities. Bacterial infection rates were similar between the 2 groups (HR = 1.10, 95% CI = 0.59-2.03, P =.76). MEBO imparted a greater analgesic effect in the first 5 days of therapy and reduced hospital costs by 8%. CONCLUSIONS: MEBO is as effective as conventional management but is not the panacea for all burn wounds. The use of MEBO eases the management of face and neck burns and facilitates early institution of occupational therapy in hand burns. It confers better pain relief such that fewer opiates are used during the first 5 days after burn injury.

Adult↗
PubMed2001

A randomized double-masked crossover study comparing latanoprost 0.005% with unoprostone 0.12% in patients with primary open-angle glaucoma and ocular hypertension.

PURPOSE: To compare the intraocular pressure)-lowering effect and side effects of latanoprost 0.005% once daily with unoprostone 0.12% twice daily. METHODS: Sixty patients with primary open-angle glaucoma or ocular hypertension were randomized to receive either latanoprost once daily in the evening and placebo once daily in the morning, or unoprostone twice daily in the morning and evening. The study was double masked and followed a crossover design with two treatment periods of 1 month separated by a 3-week washout period. The intraocular pressure was measured at 9 AM and 5 PM on the baseline and day 28 visits, and at 9 AM on day 2 and day 14 visits of each treatment period. The 9 AM measurement was taken 2 hours and 13 hours after the last drop of unoprostone and latanoprost, and the 5 PM measurement was at 10 and 21 hours, respectively. The mean of the measurements was calculated. Safety parameters were also recorded. RESULTS: Fifty-six patients completed both treatment periods and had intraocular pressure data available for evaluation. After 1 month of treatment, latanoprost significantly reduced intraocular pressure (mean +/- SEM) by 6.1 +/- 0.5 mm Hg (P <.001) and unoprostone by 4.2 +/- 0.4 mm Hg (P <.001) adjusted from an overall baseline of 22.3 +/- 0.5 mm Hg and 23.2 +/- 0.4 mm Hg, respectively. The difference of 1.9 mm Hg between treatments was statistically significant in favor of latanoprost [P =.003, analysis of covariance (ANCOVA)]. Unadjusted analysis of responders using the percentage decrease in intraocular pressure showed that the proportion of responders in the latanoprost-treated group was greater than in the unoprostone-treated group. Adverse ocular symptoms and findings were mild in both treatment groups. Eye redness and ocular irritation were the most frequently reported events. CONCLUSIONS: Latanoprost once daily was significantly more effective in reducing intraocular pressure compared with unoprostone twice daily after 1 month of treatment in patients with primary open-angle glaucoma and ocular hypertension. Both drugs were well tolerated with few ocular adverse events.

Adult↗
PubMed2001

Alendronate for the prevention of bone loss in patients on inhaled steroid therapy.

One hundred women on inhaled steroid therapy (dose range from 800 to <1600 microg per day) were randomized to receive 10 mg of oral alendronate or placebo (with 500 mg of calcium in the form of daily calcium carbonate). Bone mineral density (BMD) was measured at baseline, 6 months, and 12 months. The percentage changes in BMD were -0.80% in the placebo group and 2.99% in the alendronate group at the spine (p < 0.001 by analysis of covariance [ANCOVA]), and were -0.51% in the placebo group and 0.97% in the alendronate group at the femoral neck (p < 0.05 by ANCOVA). Five patients in the alendronate-treated group, and a similar number of patients in the placebo group, complained of mild gastric discomfort. We conclude that women on inhaled steroid therapy were at risk of accelerated bone loss, which could be prevented by a daily dose of 10 mg of alendronate.

Administration, Inhalation↗
PubMed2001

Clinical evaluation of the Mapleson theoretical ideal fresh gas flow sequence at the start of low-flow anaesthesia with isoflurane, sevoflurane and desflurane.

Mapleson used a computer spreadsheet model to predict the theoretical ideal fresh gas flow sequence at the start of low-flow anaesthesia. The aim was to increase the end-expired partial pressure of inhalational agent (PE'an) to one minimum alveolar concentration (MAC) as quickly as practicable and then to keep it constant. Ninety adult patients undergoing elective tonsillectomy under general anaesthesia were randomly allocated to one of three groups (n = 30) to receive isoflurane, sevoflurane or desflurane in oxygen. Fresh gas flow and vaporiser settings as specified by Mapleson were followed in all cases except that the maximum setting for desflurane was 18% (2.7 MAC instead of 3 MAC). Recordings of PE'an were made at 1, 2, 3, 4, 5, 7, 10, 15 and 20 min. Mean values of PE'an exceeded 1 MAC by 2 min in all three groups and remained above this value throughout. Each group's PE'an measurements were divided by their respective 1-MAC value. A simple two-level model (with patients at level 2 and time at level 1), with measurements at 1 min excluded, showed that the fitted value at 2 min and the time-weighted mean for 2-20 min for PE'iso (1.042 [95% CI 0.980-1.104] and 1.044 [0.984-1.104], respectively) were not significantly different from its 1-MAC value, whereas those of the PE'sevo (1.169 [1.119-1.219] and 1.143 [1.119-1.219]) and PE'des (1.305 [1.261-1.349] and 1.140 [1.098-1.182]) were significantly higher than their respective 1-MAC values. The Mapleson concept of an initial high fresh gas flow and high vaporiser settings, followed first by reduced high fresh gas flow, as followed in this clinical study, results in PE'an values close to or slightly higher than predicted in the spreadsheet model.

Adult↗
PubMed2001

Cefepime versus vancomycin plus netilmicin therapy for continuous ambulatory peritoneal dialysis-associated peritonitis.

Cefepime is a cephalosporin with a broad spectrum of activity against most gram-positive and gram-negative pathogens. In this study, we attempted to compare the safety and efficacy of cefepime monotherapy against the potentially more toxic combination of vancomycin and netilmicin in the treatment of continuous ambulatory peritoneal dialysis (CAPD)-associated bacterial peritonitis. Eighty-one consecutive CAPD patients who presented with peritonitis from January 1, 1998, to June 30, 2000, were recruited for study. Patients were randomized to be administered either intraperitoneal (IP) cefepime, 1 g once daily (group A), or intravenous vancomycin and netilmicin at conventional doses (group B) for 10 days. Bacterial growth was obtained in 52 episodes (66%), and pathogens identified included gram-positive organisms (30 episodes; 38%), gram-negative organisms (14 episodes; 18%), mixed organisms (2 episodes; 2.5%), and fungus (6 episodes; 8%). Eight patients were excluded after randomization for various reasons (6 patients, fungal peritonitis; 2 patients, wrong diagnoses). Because of the relatively low peritonitis rate after the use of a disconnect system, the sample size of this study was relatively small, giving a power of 0.45. There were no significant differences in primary response rates and cure rates (no relapse >28 days after completion of antibiotic therapy) between both groups of patients (group A versus group B, 82% [32 of 39 patients] versus 85% [29 of 34 patients] and 72% [28 of 39 patients] versus 76% [26 of 34 patients], respectively; P = not significant). No significant side effect was encountered in either group. Total peritonitis-related hospitalizations were 84 patient-days (1, 7, 8, 11, 20, and 37 patient-days) and 115 patient-days (3, 6, 9, 14, 21, 21, and 41 patient-days), whereas total costs per patient cure were estimated to be US $1,039 and US $1,371 in groups A and B, respectively. We conclude that once-daily 1-g IP cefepime monotherapy is a simple, safe, and cost-effective alternative to vancomycin and netilmicin therapy in the treatment of CAPD-associated bacterial peritonitis.

Adult↗
PubMed2001

Hypokalemic metabolic acidosis attributed to cough mixture abuse.

This report describes a patient with mixed normal anion gap hyperchloremic metabolic and respiratory acidosis associated with hypokalemia attributed to cough mixture abuse. Metabolic acidosis was likely related to an overdose of ammonium chloride, whereas respiratory acidosis was probably related to the effect of hypokalemia on respiratory muscles, causing hypoventilation. Hypokalemia was caused by a transcellular shift of potassium induced by ephedrine and pseudoephedrine. Both ammonium chloride and ephedrine were probably present in the cough mixture obtained by our patient as an over-the-counter medication. Physicians should be aware of the potential for cough mixture abuse to cause major electrolyte disturbances that may carry the risk for major cardiac arrhythmias, particularly in youth.

Acidosis↗
PubMed2001

The effect of topically applied aspirin on localized circumscribed neurodermatitis.

BACKGROUND: Lichen simplex chronicus is a troublesome intractable itchy dermatosis, which may persist despite intensive topical treatments. Recently it has been demonstrated that topical aspirin solution with dichloromethane has a significant antipruritic effect in an experimentally induced itch. OBJECTIVE: The aim of this double-blind, crossover placebo trial was to evaluate the efficacy of this solution in the treatment of lichen simplex chronicus. METHODS: Twenty-nine patients with lichen simplex chronicus of at least 3 months' duration that did not respond to topical corticosteroids were randomized in a double-blind fashion to receive aspirin/dichloromethane solution in treatment period 1 for 2 weeks followed by placebo in treatment period 2 or placebo followed by aspirin in period 2 with a crossover design after a 2-week washout. The patients rated the pruritus intensity before and during therapy with a visual analog scale; a blinded investigator performed photographic assessment. RESULTS: A significant therapeutic response was achieved in 11 (46%) of the patients who completed the study compared with 3 patients (12%) receiving placebo. Overall, aspirin-treated patients experienced an average decrease in the visual analog scale of 2.18 +/- 2.86 versus 0.69 +/- 2.31 of those receiving placebo. The difference between the 2 treatments for week 2 was significant (P =.03). CONCLUSION: The study suggests that topical aspirin/dichloromethane might be a practical treatment for lichen simplex chronicus.

Administration, Topical↗
PubMed2001

A comparison of the combined effect of cryotherapy and corticosteroid injections versus corticosteroids and cryotherapy alone on keloids: a controlled study.

BACKGROUND: Treatment modalities for keloids, which are commonly found in Asians, include intralesional corticosteroid injections and cryotherapy as well as a combination of these two modalities. Few studies have been performed in a controlled fashion to evaluate the efficacy of these treatments. OBJECTIVE: A controlled study, to evaluate the combined effect of intralesional corticosteroid injection with cryotherapy vs. intralesional corticosteroid or cryotherapy alone. METHODS: Ten patients completed the study: eight patients had at least three keloids and two had two keloids. Patients were treated for at least three sessions 4 weeks apart. The outcome of the lesions was compared between the treatments regarding the thickness of the lesion using a caliper and photographic assessment, and the presence of itch and pain before and after treatment using a visual analogue scale. RESULTS: In terms of thickness, the keloids responded significantly better to combined cryotherapy and triamcinolone vs. triamcinolone alone or cryotherapy alone (P < 0.001). Pain intensity was significantly lowered with all treatment modalities; however, itch was lowered only with the combined treatment and intralesional corticosteroid alone. No significant side effects were noted with any of the treatments and no re-occurrence of keloids was noted with the combined therapy. CONCLUSION: Combined injection of intralesional steroids with cryotherapy appears to be superior to other current modalities.

Adolescent↗
PubMed2001

The effect of risperidone on cognitive functioning in a sample of Asian patients with schizophrenia in Singapore.

OBJECTIVE: To evaluate the effect of risperidone treatment on the cognitive functioning in a group of Asian patients with schizophrenia METHOD: Patients with DSM-IIIR schizophrenia were recruited from Woodbridge Hospital. Several domains of cognitive functions were assessed at baseline before washout, at 8 weeks and 6 months after initiation of treatment on risperidone. Clinical outcome was assessed on the Positive and Negative Syndrome Scale (PANSS). RESULTS: Significant improvements were found in verbal fluency and certain aspects of memory 8 weeks after risperidone treatment. There were significant improvements in executive and memory functioning after 6 months. Improvements were also noted in attention and perceptual/motor processes although these did not reach significant levels. Treatment on risperidone also resulted in significant reduction in the PANSS score. CONCLUSION: Our results are consistent with those found in other studies in which risperidone was shown to be effective in improving several aspects of cognitive functioning. There were corresponding effectiveness in treating positive and negative symptoms of schizophrenia. Such improvements can have positive implications on vocational and social functioning.

Adult↗
PubMed2001

High prevalence of psychiatric morbidity in a medical intensive care unit.

This study seeks to determine the prevalence of psychiatric morbidity within a medical intensive care unit, examine its correlation with the various physiological parameters and delineate any clinical predictors for psychiatric morbidity. Seventy-seven patients who gave informed consent were administered the General Health Questionnaire (GHQ), Acute Physiological And Chronic Health Evaluation II (APACHE II) and thyroid function tests were performed. A high prevalence of psychiatric morbidity was found (36.4%). However, no statistically significant association was found between psychiatric morbidity and gender, age, APACHE II scores and thyroid function indices. Nevertheless, it is hoped that the index of suspicion for psychiatric morbidity can be raised in order to optimise the clinical management of patients within this setting.

APACHE↗