1.Molecular basis of von Hippel-Lindau syndrome in Chinese patients.
Wai-Kwan SIU ; Ronald Ching-Wan MA ; Ching-Wan LAM ; Chloe Miu MAK ; Yuet-Ping YUEN ; Fai-Man Ivan LO ; Kin-Wah CHAN ; Siu-Fung LAM ; Siu-Cheung LING ; Sui-Fan TONG ; Wing-Yee SO ; Chun-Chung CHOW ; Mary Hoi-Yin TANG ; Wing-Hung TAM ; Albert Yan-Wo CHAN
Chinese Medical Journal 2011;124(2):237-241
BACKGROUNDVon Hippel-Lindau (VHL) syndrome is an autosomal dominant familial cancer syndrome predisposing the affected individuals to multiple tumours in various organs. The genetic basis of VHL in Southern Chinese is largely unknown. In this study, we characterized the mutation spectrum of VHL in nine unrelated Southern Chinese families.
METHODSNine probands with clinical features of VHL, two symptomatic and eight asymptomatic family members were included in this study. Prenatal diagnosis was performed twice for one proband. Two probands had only isolated bilateral phaeochromocytoma. The VHL gene was screened for mutations by polymerase chain reaction, direct sequencing and multiplex ligation-dependent probe amplification (MLPA).
RESULTSThe nine probands and the two symptomatic family members carried heterozygous germline mutations. Eight different VHL mutations were identified in the nine probands. One splicing mutation, NM_000551.2: c.463+1G > T, was novel. The other seven VHL mutations, c.233A > G [p.Asn78Ser], c.239G > T [p.Ser80Ile], c.319C > G [p.Arg107Gly], c.481C > T [p.Arg161X], c.482G > A [p.Arg161Gln], c.499C > T [p.Arg167Trp] and an exon 2 deletion, had been previously reported. Three asymptomatic family members were positive for the mutation and the other five tested negative. In prenatal diagnosis, the fetuses were positive for the mutation.
CONCLUSIONSGenetic analysis could accurately confirm VHL syndrome in patients with isolated tumours such as sporadic phaeochromocytoma or epididymal papillary cystadenoma. Mutation detection in asymptomatic family members allows regular tumour surveillance and early intervention to improve their prognosis. DNA-based diagnosis can have an important impact on clinical management for VHL families.
Asian Continental Ancestry Group ; DNA Mutational Analysis ; Humans ; Polymerase Chain Reaction ; Sequence Analysis, DNA ; Von Hippel-Lindau Tumor Suppressor Protein ; genetics ; von Hippel-Lindau Disease ; genetics
3.Safe Excision of a Large Overhanging Cystic Bleb Following Autologous Blood Injection and Compression Suture.
Danny Siu Chun NG ; Ruby Hok Ying CHING ; Jason Cheuk Sing YAM ; Clement Wai Nang CHAN
Korean Journal of Ophthalmology 2013;27(2):145-148
Here, we report a large, overhanging cystic bleb that compromised vision and induced a foreign body sensation in a patient who underwent a trabeculectomy surgery with anti-metabolite therapy 4 years prior. Ultrasound biomicroscopy revealed multiple loculations with thin septa inside the bleb and a high risk of damage to the bleb was anticipated with a straight forward surgical excision. We injected autologous blood and placed a compression suture 6 weeks prior to surgical excision of the overhanging portion of the bleb. The operation was successful in preserving excellent bleb function, restoring visual acuity, and alleviating symptoms in our patient with up to 9 months of follow-up.
Blister/pathology/*surgery
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Blood Transfusion, Autologous/*methods
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Conjunctiva/pathology/surgery
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Glaucoma/*surgery
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Humans
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Male
;
Middle Aged
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Postoperative Complications/*surgery
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*Suture Techniques
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Trabeculectomy/*adverse effects
4.Safe Excision of a Large Overhanging Cystic Bleb Following Autologous Blood Injection and Compression Suture.
Danny Siu Chun NG ; Ruby Hok Ying CHING ; Jason Cheuk Sing YAM ; Clement Wai Nang CHAN
Korean Journal of Ophthalmology 2013;27(2):145-148
Here, we report a large, overhanging cystic bleb that compromised vision and induced a foreign body sensation in a patient who underwent a trabeculectomy surgery with anti-metabolite therapy 4 years prior. Ultrasound biomicroscopy revealed multiple loculations with thin septa inside the bleb and a high risk of damage to the bleb was anticipated with a straight forward surgical excision. We injected autologous blood and placed a compression suture 6 weeks prior to surgical excision of the overhanging portion of the bleb. The operation was successful in preserving excellent bleb function, restoring visual acuity, and alleviating symptoms in our patient with up to 9 months of follow-up.
Blister/pathology/*surgery
;
Blood Transfusion, Autologous/*methods
;
Conjunctiva/pathology/surgery
;
Glaucoma/*surgery
;
Humans
;
Male
;
Middle Aged
;
Postoperative Complications/*surgery
;
*Suture Techniques
;
Trabeculectomy/*adverse effects
5.Quantitative Anatomy of C7 Vertebra in Southern Chinese for Insertion of Lateral Mass Screws and Pedicle Screws.
Michael Siu Hei TSE ; Chi Hin CHAN ; Kam Kwong WONG ; Wing Cheung WONG
Asian Spine Journal 2016;10(4):705-710
STUDY DESIGN: Retrospective study. PURPOSE: To analyze the quantitative anatomy of C7 vertebra for insertion of lateral mass screws and pedicle screws in Southern Chinese patients. OVERVIEW OF LITERATURE: C7 lateral mass is smaller when compared to other subaxial cervical levels, which limits the length of lateral mass screws that can be used. Some studies have suggested pedicle screws for better fixation. But, this option is limited by the narrow pedicle width. METHODS: We have obtained computed tomography (CT) cervical spine data in 0.625 mm slices from our radiology department. The patients were adults. CTs were from May to August, 2015. The lateral mass screw length was measured using Margerl's technique and pedicle width and pedicle screw trajectory were determined in three-dimensional reformated images. RESULTS: CT scans of cervical spines of 94 patients were obtained and 188 lateral masses and pedicles of C7 vertebrae were measured. The mean lateral mass screw length was 13.2 mm (standard deviation [SD] 1.6 mm), mean outer pedicle width was 5.9 mm (SD 1.0 mm) and mean pedicle screw trajectory was 29.4 degrees (SD 3.6 degrees). Most (91.0%) of the pedicles had an outer diameter ≥4.5 mm. CONCLUSIONS: The mean lateral mass screw length was longer when compared with other similar studies, while the mean outer pedicle width was narrower. Nearly 10% of the pedicles were unable to accommodate 3.5 mm screws. These findings favor the use of lateral mass screws to provide a safe and stable fixation for C7 vertebrae in Southern Chinese patients, while the final choice of fixation method should only be confirmed after careful preoperative planning with CT scan.
Adult
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Asian Continental Ancestry Group*
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Humans
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Methods
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Pedicle Screws*
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Retrospective Studies
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Spine*
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Tomography, X-Ray Computed
6.Identification of genes expressed during myocardial development.
Siu Yuen CHAN ; Anthony Kin Wang CHAN ; Becky Pik Ki CHEUNG ; Ying LIANG ; Maurice Ping LEUNG
Chinese Medical Journal 2003;116(9):1329-1332
OBJECTIVETo identify genes expressed in the fetal heart that are potentially important for myocardial development and cardiomyocyte proliferation.
METHODSmRNAs from fetal (29 weeks) and adult cardiomyocytes were use for suppression subtractive hybridization (SSH). Both forward (fetal as tester) and reverse (adult as driver) subtractions were performed. Clones confirmed by dot-blot analysis to be differentially expressed were sequenced and analyzed.
RESULTSDifferential expressions were detected for 39 out of 96 (41%) clones on forward subtraction and 24 out of 80 (30%) clones on reverse. For fetal dominating genes, 28 clones matched to 10 known genes (COL1A2, COL3A1, endomucin, HBG1, HBG2, PCBP2, LOC51144, TGFBI, vinculin and PND), 9 clones to 5 cDNAs of unknown functions (accession AK021715, AF085867, AB040948, AB051460 and AB051512) and 2 clones had homology to hEST sequences. For the reverse subtraction, all clones showed homology to mitochondrial transcripts.
CONCLUSIONSWe successfully applied SSH to detect those genes differentially expressed in fetal cardiac myocytes, some of which have not been shown relative to myocardial development.
Aged ; Cells, Cultured ; Collagen ; Collagen Type I ; Collagen Type III ; genetics ; DNA-Binding Proteins ; genetics ; Forkhead Transcription Factors ; Gene Expression ; physiology ; Heart ; embryology ; growth & development ; Heterogeneous-Nuclear Ribonucleoproteins ; genetics ; Humans ; Nerve Tissue Proteins ; genetics ; Nucleic Acid Hybridization ; RNA-Binding Proteins ; Transcription Factors ; Transforming Growth Factor beta ; genetics ; Transforming Growth Factor beta1 ; Vinculin ; genetics
7.Inflammatory cytokines and childhood obstructive sleep apnoea.
Albert M LI ; Hugh S LAM ; Michael H M CHAN ; Hung K SO ; Siu K NG ; Iris H S CHAN ; Christopher W K LAM ; Yun K WING
Annals of the Academy of Medicine, Singapore 2008;37(8):649-654
OBJECTIVETo evaluate serum cytokine concentrations in children with and without obstructive sleep apnoea (OSA) and to investigate the effects of OSA treatment on cytokines.
MATERIALS AND METHODSConsecutive children with habitual snoring and symptoms suggestive of OSA were recruited. They completed a sleep apnoea symptom questionnaire, underwent physical examination and overnight polysomnography (PSG). OSA was diagnosed if obstructive apnoea index (OAI) >1. A blood sample was collected for analysis of IL-6, IL-8, and TNF-alpha after PSG.
RESULTSOne hundred forty-two children (97 males) with a median (IQR) age of 11.1 years (9.0-12.8) were recruited. The commonest presenting symptoms were nocturnal mouth breathing, prone sleeping position and poor attention at school. Forty-seven children were found to have OSA and they had higher serum IL-6 [0.1 (0.1-0.4) vs 0.1 (0.1-0.1) pg/mL, P = 0.001] and IL-8 [1.7 (1.0-2.3) vs 1.3 (0.9-1.7) pg/mL, P = 0.029] concentrations compared to their non-OSA counterparts. Multiple regression analysis indicated that OAI was significantly associated with both IL-6 (r = 0.351, P <0.001) and IL-8 (r = 0.266, P = 0.002). Sixteen children underwent treatment and there was significant reduction in mean (SD) serum IL-8 after intervention [pre vs post levels of 1.9 (1.0) vs 1.1 (0.6) pg/mL, P = 0.001] independent of weight loss.
CONCLUSIONChildren with OSA had elevated levels of pro-inflammatory cytokines that normalised following treatment suggesting that the inflammatory response is potentially reversible. Early detection and intervention may be beneficial.
Child ; Cytokines ; blood ; Female ; Humans ; Interleukin-6 ; blood ; Interleukin-8 ; blood ; Male ; Polysomnography ; Sleep Apnea, Obstructive ; blood ; therapy ; Tumor Necrosis Factor-alpha ; blood
8.Analysis of inborn errors of metabolism: disease spectrum for expanded newborn screening in Hong Kong.
Han-Chih Hencher LEE ; Chloe Miu MAK ; Ching-Wan LAM ; Yuet-Ping YUEN ; Angel On-Kei CHAN ; Chi-Chung SHEK ; Tak-Shing SIU ; Chi-Kong LAI ; Chor-Kwan CHING ; Wai-Kwan SIU ; Sammy Pak-Lam CHEN ; Chun-Yiu LAW ; Hok-Leung Morris TAI ; Sidney TAM ; Albert Yan-Wo CHAN
Chinese Medical Journal 2011;124(7):983-989
BACKGROUNDData of classical inborn errors of metabolism (IEM) of amino acids, organic acids and fatty acid oxidation are largely lacking in Hong Kong, where mass spectrometry-based expanded newborn screening for IEM has not been initiated. The current study aimed to evaluate the approximate incidence, spectrum and other characteristics of classical IEM in Hong Kong, which would be important in developing an expanded newborn screening program for the local area.
METHODSThe laboratory records of plasma amino acids, plasma acylcarnitines and urine organic acids analyses from year 2005 to 2009 inclusive in three regional chemical pathology laboratories providing biochemical and genetic diagnostic services for IEM were retrospectively reviewed.
RESULTSAmong the cohort, 43 patients were diagnosed of IEM, including 30 cases (69%) of amino acidemias (predominantly citrin deficiency, hyperphenylalaninemia due to 6-pyruvoyl-tetrahydropterin synthase deficiency and tyrosinemia type I), 5 cases (12%) of organic acidemias (predominantly holocarboxylase synthetase deficiency) and 8 cases (19%) of fatty acid oxidation defects (predominantly carnitine-acylcarnitine translocase deficiency). The incidence of classical IEM in Hong Kong was roughly estimated to be at least 1 case per 4122 lives births, or 0.243 cases per 1000 live births. This incidence is similar to those reported worldwide, including the mainland of China. The estimated incidence of hyperphenylalaninemia was 1 in 29 542 live births.
CONCLUSIONSOur data indicate that it is indisputable for the introduction of expanded newborn screening program in Hong Kong. Since Hong Kong is a metropolitan city, a comprehensive expanded newborn screening program and referral system should be available to serve the neonates born in the area.
Acids ; urine ; Amino Acids ; blood ; Carnitine ; analogs & derivatives ; blood ; Hong Kong ; epidemiology ; Humans ; Infant, Newborn ; Metabolism, Inborn Errors ; blood ; diagnosis ; epidemiology ; urine ; Neonatal Screening ; methods ; Tandem Mass Spectrometry
9.Regulation of Na+ absorption and Cl- secretion in the endometrium: switching mechanisms.
Hsiao Chang CHAN ; Ling Nga CHAN ; Xiao Fei WANG ; Lei Ling TSANG ; Siu Chang SO
Journal of Korean Medical Science 2000;15(Suppl):S34-S35
No abstract available.
Animal
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Chlorides/metabolism*
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Endometrium/metabolism*
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Female
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Mice
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Sodium/metabolism*
10.Endovascular Management of Hepatic Artery Pseudoaneurysms: A Case Series
Pui Lam CHEUNG ; Yat Sing LEE ; Chong Boon TAN ; Hin Yue LAU ; Chi Wai SIU ; Chik Xing CHAN ; Wai Tat CHAN ; Cheuk Him HO
Vascular Specialist International 2023;39(1):1-
Although rare, hepatic artery aneurysms are associated with a high morbidity and mortality, necessitating a prompt diagnosis. A significant proportion of hepatic artery aneurysms are pseudoaneurysms, and the major risk factors of which have already been identified in previous literatures. Presentation can be variable, but diagnosis almost relies entirely on computed tomography and digital subtraction angiography. The endovascular approach has progressively become the preferred option due to its better performance when compared to the traditional surgical approach. However, formulation of an endovascular treatment plan for these lesions remains difficult as multiple factors should be considered to identify the best endovascular treatment modality. Five cases of pseudoaneurysm due to recent Whipple operation, hepatobiliary infections, and underlying malignancy are presented in this article to illustrate the effectiveness and complexity of endovascular treatment in this disease entity.