Biomedical subjects
Publications and source records attributed to Y Hui.
We describe a child who has congenital nasal pyriform aperture stenosis with single maxillary central incisor, holoprosencephaly and central diabetes insipidus without any apparent anterior pituitary dysfunction. Conservative management of the congenital nasal pyriform aperture stenosis is adopted and management of diabetes insipidus is described. A literature review is undertaken.
Recurrent respiratory papillomatosis (RRP) is a rare disease in children. Previous reports suggested that prematurity and early age of presentation were poor prognostic factors. We report on a 24-week premature infant who presented with stridor, weak cry, and hoarseness of voice at age 9 months (corrected age), in whom the diagnosis of RRP was not made until age 21 months (corrected age). Laser excision of RRP was subsequently performed, and the child is still surviving at age 2.5 years. RRP should be considered in the differential diagnosis of airway problems in survivors of extreme prematurity; the prognosis is not uniformly poor in premature infants.
BACKGROUND: The role of Helicobacter pylori eradication in the management of gastro-oesophageal reflux disease (GORD) is controversial. We hypothesised that H pylori eradication leads to worsened control of reflux disease. METHODS: Consecutive patients with weekly reflux symptoms were prospectively recruited for endoscopy and symptom evaluation. Patients were enrolled if they had H pylori infection and required long term acid suppressants. Eligible patients were randomly assigned to omeprazole triple therapy (HpE group) or omeprazole with placebo antibiotics (Hp+ group) for one week. Omeprazole 20 mg daily was given for eight weeks for healing of oesophagitis and symptom relief. This was followed by a maintenance dose of 10 mg daily for up to 12 months. The primary study end point was the probability of treatment failure within 12 months, which was defined as either incomplete resolution of symptoms or oesophagitis at the initial treatment phase, or relapse of symptoms and oesophagitis during the maintenance phase. Predictors of treatment failure were determined by Cox's proportional hazards model. RESULTS: A total of 236 GORD patients were screened and 113 (47.9%) were positive for H pylori; 104 (92%) patients were included in the intention to treat analysis (53 in the HpE group and 51 in the Hp+ group). Thirty one patients (30%) had erosive oesophagitis at baseline. H pylori was eradicated in 98% of the HpE group and in 3.9% of the Hp+ group. Overall, 15 patients (28.3%) in the HpE group and eight patients (15.7%) in the Hp+ group had treatment failure. The 12 month probability of treatment failure was 43.2% (95% confidence interval (CI) 29.9-56.5%) in the HpE group and 21.1% (95% CI 9.9-32.3%) in the Hp+ group (log rank test, p = 0.043). In the Cox proportional hazards model, after adjustment for the covariates age, sex, erosive oesophagitis, hiatus hernia, degree of gastritis, and severity of symptoms at baseline, H pylori eradication was the only predictor of treatment failure (adjusted hazard ratio 2.47 (95% CI 1.05-5.85)). CONCLUSION: H pylori eradication leads to more resilient GORD.
OBJECTIVE: To assess the feasibility of implementing a universal neonatal hearing screening programme using distortion product otoacoustic emission detection at a major teaching hospital in Hong Kong. DESIGN: Descriptive study and questionnaire. SETTING. Teaching hospital, Hong Kong. METHODS: A total of 1064 infants, together with their mothers, were successfully recruited for the study. The participation rate was 99.3%. A three-stage hearing screening protocol using distortion product otoacoustic emission detection was adopted. Each of the participating infants was screened on three separate occasions (day 1-4, day 5-14, and day 21-30 after birth), irrespective of the test results. A questionnaire was administered to 364 randomly selected mothers to determine whether as consumers of the hearing screening service, mothers would find screening desirable. RESULTS: Results of the screening demonstrated an incidence of permanent bilateral hearing loss (>or=40 dB in the better ear) of 0.28%. The results also showed that 3.5% of the screened infants were referred for subsequent diagnostic audiological assessment, including those suspected with unilateral as well as bilateral hearing loss. Data obtained were comparable to other reported results obtained using multi-stage screening protocols. Taking both the false positive rate and the default rate into consideration, the most appropriate time for screening in this hospital setting appeared to be around day 5 to 14 when infants returned to the hospital's day centre as out-patients for routine medical follow-up. Since this day centre service is not generally provided by all maternity hospitals in Hong Kong, an alternative time for screening would be around day 21 to 30 when infants could return as out-patients solely for the hearing test. The results of the questionnaire suggested that most mothers thought a neonatal hearing screening would be desirable (91.35%). The majority (81.70%) indicated a preference for screening either within a few days of birth at the maternity ward prior to discharge from the hospital, or between 5 and 30 days when returning to the hospital as an out-patient. CONCLUSION: It was concluded that a universal neonatal hearing screening programme could be readily implemented in a maternity hospital setting in Hong Kong.
BACKGROUND: Whether Helicobacter pylori increases the risk of ulcers in patients taking non-steroidal anti-inflammatory drugs (NSAIDs) is controversial. We hypothesised that eradication of H pylori infection would reduce the risk of ulcers for patients starting long-term NSAID treatment. METHODS: Patients were enrolled if they were NSAID naïve, had a positive urea breath test, had dyspepsia or an ulcer history, and required long-term NSAID treatment. They were randomly assigned omeprazole triple therapy (eradication group) or omeprazole with placebo antibiotics (placebo group) for 1 week. All patients were given diclofenac slow release 100 mg daily for 6 months from randomisation. Endoscopy was done at 6 months or if severe dyspepsia or gastrointestinal bleeding occurred. The primary endpoint was the probability of ulcers within 6 months. Analyses were by intention to treat. FINDINGS: Of 210 arthritis patients screened, 128 (61%) were positive for H pylori. 102 patients were enrolled, and 100 were included in the intention-to-treat analysis. H pylori was eradicated in 90% of the eradication group and 6% of the placebo group. Five of 51 eradication-group patients and 15 of 49 placebo-group patients had ulcers. The 6-month probability of ulcers was 12.1% (95% CI 3.1-21.1) in the eradication group and 34.4% (21.1-47.7) in the placebo group (p=0.0085). The corresponding 6-month probabilities of complicated ulcers were 4.2% (1.3-9.7) and 27.1% (14.7-39.5; p=0.0026). INTERPRETATION: Screening and treatment for H pylori infection significantly reduces the risk of ulcers for patients starting long-term NSAID treatment.
Patients with chronic hepatitis B (CHB) may develop severe disease exacerbations (flare) with jaundice, and some may progress to fulminant hepatic failure. Whether early administration of lamivudine can prevent liver failure and mortality is uncertain. We investigated the role of lamivudine treatment in severe hepatitis B virus (HBV) exacerbations. Consecutive patients presented with severe flare-up of HBV (new onset of jaundice plus alanine aminotransferase greater than five times upper limit of normal) treated with lamivudine and historical controls who did not receive lamivudine were studied. All patients had no hepatic encephalopathy on admission. Univariate analysis and multivariate logistic regression were performed on various clinical and laboratory factors for the prediction of mortality. Twenty-eight patients treated with lamivudine and 18 controls were identified. Overall, nine patients died and two other received liver transplants for fulminant hepatic failure. Six of 28 (21.4%) lamivudine-treated patients vs five of 18 (27.8%) controls died or received a liver transplant (P = 0.62). On multivariate analysis, platelet < or = 143 x 10E9/L (odds ratio 22.4, 95% CI 1.8-281.6) and bilirubin > 172 micromol/L (odds ratio 18.4, 95% CI 1.5-228.5) were independent predictors of liver-related mortality. The mortality of patients who had thrombocytopenia and high bilirubin, thrombocytopenia, high bilirubin, and no risk factor were 69.2%, 11.1%, 12.5% and 0% respectively. Hence lamivudine confers no survival benefit to conventional treatment in severe exacerbations of CHB. Patients with thrombocytopenia and high bilirubin should be considered for liver transplantation.
OBJECTIVE: Osteoporosis is rapidly becoming a major health problem in Hong Kong with the ever-increasing population of elderly people. Its importance lies in the predisposition to fragility fractures of patients with the disease. These fractures incur morbidity and mortality to the elderly. Measures are needed to reduce the prevalence of osteoporosis and the incidence of osteoporotic fractures. A screening programme is potentially the way forward in achieving such a goal. STUDY SELECTION AND DATA EXTRACTION: The need for, and the feasibility of, a screening programme for osteoporosis in Hong Kong were evaluated. A comprehensive examination of the relevant issues was carried out within the framework of the World Health Organization criteria on screening of diseases. Major studies from abroad and Hong Kong were discussed and the strength of evidence was assessed. DATA SYNTHESIS: Osteoporosis satisfies some of the World Health Organization criteria for screening of diseases: it is a significant health problem, the natural history is fairly well understood, and early detection is possible. Nevertheless, there remain unresolved issues related to the screening tests, the treatments currently available, and the selection criteria for treatment. Several therapeutic options have been tested in trials. However, more work is needed to determine whether, in addition to increasing bone mass, they reduce the incidence of fracture. Moreover, the duration of therapy needed to achieve long-term benefit has yet to be established. More studies are also needed to evaluate the cost-effectiveness of such a programme. CONCLUSION: There undoubtedly needs to be a means of identifying individuals who have osteoporosis and are susceptible to fragility fractures. However, based on the currently available evidence, large-scale screening is not a valid option. Before instituting such a programme in Hong Kong, more studies are needed to determine the most appropriate and cost-effective way forward.
Explore the source record for details and available documents.
Two classes of cysteinyl leukotriene receptor, CysLT(1) and CysLT(2), have been identified and pharmacologically characterized in human tissues. Although the CysLT(1) receptor mediates the proinflammatory effects of leukotrienes in human asthma, the physiological roles of CysLT(2) receptor are not defined, and a suitable mouse model would be useful in delineating function. We report here the molecular cloning and characterization of the mouse CysLT(2) receptor (mCysLT(2)R) from heart tissue. mCysLT(2)R cDNA encodes a protein of 309 amino acids, truncated at both ends compared with the human ortholog (hCysLT(2)R). The gene resides on the central region of mouse chromosome 14 and is composed of 6 exons with the entire coding region located in the last exon. Two 5'-untranslated region splice variants were identified with the short form lacking exon 3 as the predominant transcript. Although the overall expression of mCysLT(2)R is very low, the highest expression was detected in spleen, thymus, and adrenal gland by ribonuclease protection assay, and discrete sites of expression in heart were observed by in situ hybridization. Intracellular calcium mobilization in response to cysteinyl leukotriene administration was detected in human embryonic kidney 293T cells transfected with recombinant mCysLT(2)R with a rank order of potency leukotriene C(4)(LTC(4) ) = LTD(4)>>LTE(4). [(3)H]LTD(4) binding to membranes expressing mCysLT(2)R could be effectively competed by LTC(4) and LTD(4) and only partially inhibited by LTE(4) and BAYu9773. The identification of mCysLT(2)R will be useful for establishing CysLT(2)R-deficient mice and determining novel leukotriene functions.
Nine glycosides bearing the disaccharide of OSW-1, namely 2-O-(4-methoxybenzoyl)-beta-D-xylopyranosyl-(1-->3)-2-O-acetyl-alpha-L-arabinopyranosides, were synthesized, and their antitumor activities were tested.
Five analogues, including a 16-epi-isomer (6), and a 3-terephthalic acid linked dimer (8) of OSW-1 were synthesized. Their inhibitory activities on P388 and A-549 cells were detected.
BACKGROUND: Many patients who have had upper gastrointestinal bleeding continue to take low-dose aspirin for cardiovascular prophylaxis or other non-steroidal antiinflammatory drugs (NSAIDs) for musculoskeletal pain. It is uncertain whether infection with Helicobacter pylori is a risk factor for bleeding in such patients. METHODS: We studied patients with a history of upper gastrointestinal bleeding who were infected with H. pylori and who were taking low-dose aspirin or other NSAIDs. We evaluated whether eradication of the infection or omeprazole treatment was more effective in preventing recurrent bleeding. We recruited patients who presented with upper gastrointestinal bleeding that was confirmed by endoscopy. Their ulcers were healed by daily treatment with 20 mg of omeprazole for eight weeks or longer. Then, those who had been taking aspirin were given 80 mg of aspirin daily, and those who had been taking other NSAIDs were given 500 mg of naproxen twice daily for six months. The patients in each group were then randomly assigned separately to receive 20 mg of omeprazole daily for six months or one week of eradication therapy, consisting of 120 mg of bismuth subcitrate, 500 mg of tetracycline, and 400 mg of metronidazole, all given four times daily, followed by placebo for six months. RESULTS: We enrolled 400 patients (250 of whom were taking aspirin and 150 of whom were taking other NSAIDs). Among those taking aspirin, the probability of recurrent bleeding during the six-month period was 1.9 percent for patients who received eradication therapy and 0.9 percent for patients who received omeprazole (absolute difference, 1.0 percent; 95 percent confidence interval for the difference, -1.9 to 3.9 percent). Among users of other NSAIDs, the probability of recurrent bleeding was 18.8 percent for patients receiving eradication therapy and 4.4 percent for those treated with omeprazole (absolute difference, 14.4 percent; 95 percent confidence interval for the difference, 4.4 to 24.4 percent; P=0.005). CONCLUSIONS: Among patients with H. pylori infection and a history of upper gastrointestinal bleeding who are taking low-dose aspirin, the eradication of H. pylori is equivalent to treatment with omeprazole in preventing recurrent bleeding. Omeprazole is superior to the eradication of H. pylori in preventing recurrent bleeding in patients who are taking other NSAIDs.
Polyphyllin D, namely diosgenyl alpha-L-rhamnopyranosyl-(1 --> 2)- [(alpha-L-arabinofuranosyl)-(1 --> 4)]-[beta-D-glucopyranoside, was synthesized from diosgenyl-beta-D-glucopyranoside in four steps and in 30% overall yield, taking advantage of regioselective pivaloylation and alpha-L-rhamnopyranosylation reactions.
BACKGROUND: Prophylactic misoprostol or non-steroidal anti-inflammatory drugs (NSAIDs) with low gastric toxicity (nabumetone) has been shown to reduce mucosal injury. AIM: To compare nabumetone vs. co-therapy of naproxen with low-dose misoprostol for secondary prevention of upper gastrointestinal bleeding in NSAID users. METHODS: NSAID users presenting with upper gastrointestinal bleeding were enrolled if they required long-term NSAIDs. After ulcer healing, they were randomized to receive: naproxen (500-1000 mg/day) and misoprostol (200 microg b.d.), or nabumetone (1000-1500 mg/day) and placebo misoprostol for 24 weeks. The primary end-point was recurrent upper gastrointestinal bleeding. The secondary end-point was the proportion of patients suffering from major gastrointestinal events including ulcer bleeding, symptomatic ulcers and severe dyspepsia. RESULTS: A total of 90 patients were included in the intention-to-treat analysis (misoprostol/naproxen 45, nabumetone 45). Recurrent bleeding occurred in 10 patients (22.2%) receiving misoprostol/naproxen compared with three (6.7%) receiving nabumetone (relative risk 3.33, 95% CI: 0.98-11.32, P=0.069). The proportion of patients suffering from major gastrointestinal events at 24 weeks was 31.1% in the misoprostol/naproxen group and 28.9% in the nabumetone group. CONCLUSIONS: Misoprostol/naproxen is not superior to nabumetone for secondary prevention of upper gastrointestinal bleeding. Neither low-dose misoprostol nor nabumetone is adequate for high-risk NSAID users.
OBJECTIVES: To study the relationship between the size of neopharynx after total laryngectomy and long-term swallowing function by means of scintigraphy. STUDY DESIGN: The width of pharyngeal remnant was measured during surgery in 11 patients. Their swallowing function was assessed by scintigraphy 8 to 10 years after surgery. METHODS: The width of pharyngeal remnant at its narrowest point in both relaxed and stretched state was measured during surgery. Postoperative scintigraphy data on swallowing were obtained and computed along 3 lines, (1) transit time through neopharynx, (2) percentage of bolus transferred, and (3) swallowing efficiency. The relationship between the 2 sets of data was analyzed by linear regression analysis. RESULTS: (1) No statistically significant relationship was found between the size of neopharynx and swallowing function. (2) All patients are clinically asymptomatic. CONCLUSIONS: The swallowing function is not affected by the size of the neopharynx in 11 patients with pharyngeal remnant width ranging from 3 to 8 cm (stretched).
Trans-sphenoidal removal of pituitary tumours using the endonasal endoscopic technique, a novel application, is herein reported in five consecutive patients with growth-hormone-secreting pituitary adenomas seen at a teaching hospital in Hong Kong. All five patients demonstrated complete tumour removal on postoperative imaging and hormonal assessment following the procedure. Surgical morbidity and symptoms were minimal; postoperative obstructive nasal packing was not required with this technique, which greatly improved patient comfort. Preliminary experience suggests that the endonasal endoscopic approach is a safe and effective alternative to the conventional trans-septal microscopic method for the treatment of pituitary tumour. A randomised controlled trial comparing these two approaches is currently underway at this institution.
OBJECTIVE: To observe the expression of vimentin in the lens epithelial cells and superficial cortex of age-related cataract. METHODS: Twenty-six paraformaldehyde-fixed flat preparations of human lens epithelium attached to the anterior capsule and obtained during extracapsular cataract extraction were studied. Of these, 22 were studied and compared to the 10 samples from normal lenses with antibody to vimentin by avidinbiotinylated peroxidase complex (ABC) method and observed with a light microscope, and 6 (4 cataractous and 2 normal) were used for pre-embedding immunoelectron microscopy. Vimentin in superficial layers (epithelium and superficial cortex) of 4 cataractous lenses were analysed by SDS-polyacrylamide gel electrophoresis (PAGE) and Western blot method. RESULTS: The average gray level values for expression of vimentin were 143.84 +/- 8.52 and 134.87 +/- 14.27 in cataract and normal group, respectively (t = 2.0948, P < 0.05). Ultrastructure of epithelial cells showed a decrease of intermediate filaments, accumulation of vimentin in bundle and organelle degeneration. Vimentin was identified in the superficial layers of normal and immature cataractous lenses by SDS-PAGE and Western blot. In another two mature cataractous lenses, little vimentin was detected. CONCLUSION: Decrease of vimentin may be initiated by damage to the epithelial cells leading to degradation of cytoskeleton, and appears to be related with the formation of age-related cataract.
OBJECTIVE: To study the distinctive clinicopathologic and immunohistochemical difference between ovarian metastatic carcinomas and primary ovarian carcinomas. METHODS: The clinical and pathological features of 27 cases of ovarian metastatic carcinomas (gastric carcinomas 12 cases, colon carcinomas 11 cases, others 4 cases) obtained from our department were reviewed. Immunostainings for CK (AE1/AE3), CK7, CK20, CEA, vimentin, nm23 were performed with SP staining methods. RESULTS: On gross examination, metastasis from gastric adenocarcinoma were usually bilateral, while solid (11/12) and metastases from colonic adenocarcinoma were more often unilateral and cystic (7/11). Microscopically, metastases from gastric adenocarcinoma revealed signet ring cells or poorly differentiated adenocarcinomas (12/12), whereas metastases from colonic adenocarcinomas showed similar morphology of endometrioid adenocarcinoma (8/11). The majority of ovarian metastases of gastric carcinoma (7/12) and colon carcinoma (8/11) were CK20 positive. In particular, CK20 was invariably expressed in colon cancer metastases. Most of the ovarian metastatic carcinomas from the gastrointestinal tract failed to react with immunostaining of CK7. A combined use of CEA, vimentin and nm23 had made a correct classification for 11/12 cases of the gastric carcinoma, 10/11 cases of the colonic cancer. CONCLUSIONS: CK7 and CK20 have been proved to be useful antibodies in distinguishing between metastatic carcinomas and primary carcinomas of the ovary. Combined use of a panel of antibodies can give more significant results.