Biomedical subjects

Wai Shan Wong

Publications and source records attributed to Wai Shan Wong.

3 recordsLinked to original sources

PubMed2026

Alpha-thalassaemia early eluting peak for alpha-thalassaemia --SEA carrier screening: a multicentre diagnostic comparison with immunochromatographic strip test and haemoglobin H inclusion test.

While high-performance liquid chromatography (HPLC) is well-established for β-thalassaemia and haemoglobinopathies, phenotypic screening for α0-thalassaemia has been limited. To address this limitation, we aimed to translate the discovery of the α-thalassemia early eluting peak (αEEP) in HPLC into clinical practice by comparing its diagnostic performance with other existing methods (haemoglobin H inclusion test [HbHi] and immunochromatographic strip test [ICT]) in a multicentre setting, and elucidating the nature of the αEEP by liquid chromatography-tandem mass spectrometry (LC-MS/MS). With a cohort of 820 genotyped patients, the αEEP showed superior diagnostic performance in detecting --SEA (sensitivity 99.6%, specificity 100%) compared with HbHi (sensitivity 95.8%, P = 0.006; specificity 97.3%, P < 0.001) and ICT (sensitivity 95.8%, P = 0.006; specificity 75.4%, P < 0.001). Both HbHi and ICT showed reduced sensitivity in β-thalassaemia carriers versus non-carriers. ICT showed reduced specificity when Hb F ≥ 1% compared with < 1%. The αEEP remained robust across all subgroups. LC-MS/MS revealed a strong association between the αEEP and embryonic ζ-globin chains (P < 0.001). The αEEP offered cost reductions of 98.6% over HbHi and 97.3% over ICT. Collectively, the αEEP is a highly reliable and cost-effective marker for detecting --SEA carriers, enabling a novel "all-in-one" HPLC screening strategy for --SEA, β-thalassaemia and haemoglobinopathies. Trial registration number: not applicable.

Humans↗

PubMed2006

4q loss is potentially an important genetic event in MM tumorigenesis: identification of a tumor suppressor gene regulated by promoter methylation at 4q13.3, platelet factor 4.

In this study, we have elucidated the chromosomal imbalances in the multistep pathogenesis and delineated several critical tumor suppressor gene (TSG) loci in multiple myeloma (MM). By using comparative genomic hybridization, allelotyping, and multicolor interphase fluorescence in situ hybridization, 5 MM cell lines and bone marrow CD138+ plasma cells from 88 Chinese patients with monoclonal gammopathy of undetermined significance (MGUS) and early and advanced stages of MM were investigated. In all MGUS and MM samples, chromosome copy number abnormalities were detected. A higher number of chromosomal imbalances and specific genetic alterations are involved in MGUS to MM transition (-6q, +3p, and +1p) and MM progression (+2p and +9q). In addition to -13q, we first found high frequencies (42% to 46%) of -4q involving high percentages (70% to 74%) of clonal plasma cells in both MGUS and MM, suggesting that inactivation of TSG in this region is also a potentially critical genetic event in MM tumorigenesis. By high-resolution allelotyping, we defined a common deletion region on 4q13.3 and found that a candidate TSG, platelet factor 4, was frequently silenced by promoter hypermethylation in MM (15 of 28) and MM cell lines (5 of 5). These data have opened up a new approach in the molecular targeting therapy and provide novel insights into MM tumorigenesis.

Aged↗

PubMed2003

Initial treatment of immune thrombocytopenic purpura with high-dose dexamethasone.

BACKGROUND: The role of high-dose dexamethasone in the treatment of immune thrombocytopenic purpura in adults is controversial. We assessed the effectiveness of high-dose dexamethasone as initial treatment in a series of consecutive adults with immune thrombocytopenic purpura. METHODS: Consecutive patients with newly diagnosed immune thrombocytopenic purpura and a platelet count of less than 20,000 per cubic millimeter or a platelet count of less than 50,000 per cubic millimeter and clinically significant bleeding were enrolled between January 1997 and December 2000. Oral dexamethasone at a dose of 40 mg per day for four consecutive days was the initial treatment. A response was defined as an increase in the platelet count of at least 30,000 per cubic millimeter and a platelet count of more than 50,000 per cubic millimeter by day 10 after the initiation of treatment. A sustained response was defined as a platelet count of more than 50,000 per cubic millimeter six months after the initial treatment. RESULTS: Of 157 consecutive patients, 125 were eligible. The mean (+/-SD) platelet count before treatment was 12,200+/-11,300 per cubic millimeter. A good initial response to high-dose dexamethasone occurred in 106 of the 125 patients (85 percent): the platelet count increased by at least 20,000 per cubic millimeter by the third day of treatment, and the mean platelet count was 101,400+/-53,200 per cubic millimeter (range, 50,000 to 260,000 per cubic millimeter) one week after the initiation of treatment. Among the 106 patients with a response, 53 (50 percent) had a sustained response; the other 53 (50 percent) had a relapse within six months, most of them (94 percent) within the first three months. A platelet count of less than 90,000 per cubic millimeter on day 10 was associated with a high risk of relapse. The treatment was well tolerated. CONCLUSIONS: A four-day course of high-dose dexamethasone is effective initial therapy for adults with immune thrombocytopenic purpura.

Administration, Oral↗