1.Gastrointestinal Cytomegalovirus infection in non-human immunodeficiency virus infected patients.
Ng KL ; Ho J ; Ng HS ; Luman W
The Medical Journal of Malaysia 2003;58(3):337-344
This is a retrospective study of fourteen patients who had proven Cytomegalovirus (CMV) infection of the gastrointestinal tract with no Human Immunodeficiency virus infection. The median age was 60.5 (Range 28 to 81) years. Eight patients were below (Group 1) and six above sixty five years old (Group 2). Areas of gastro-intestinal involvement were: oesophagus (2), stomach (1), colon (10) and multiple sites (1). Seven patients from Group 1 had received immunosuppressive therapy at the time of presentation and one had diabetes mellitus. We found a high prevalence of co-morbidities such as chronic renal failure and diabetes mellitus in Group 2. At median follow up of 13.9 months, there was a mortality rate of 50%. Only four patients were treated with ganciclovir. Our study concludes that the gastrointestinal CMV diseases in young patients were associated with immunosuppression whereas the older patients had chronic renal failure or diabetes.
Cytomegalovirus Infections/*immunology
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Gastrointestinal Diseases/*virology
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HIV Infections
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*Immunocompetence
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Retrospective Studies
2.Antioxidant Activities and Total Phenolic Content of Aqueous Extract of Pleurotus ostreatus (Cultivated Oyster Mushroom)
Yim HS ; Chye FY ; Tan CT ; Ng YC ; Ho CW
Malaysian Journal of Nutrition 2010;16(2):281-291
Pleurotus ostreatus better known as oyster mushroom is widely cultivated and consumed as food in Malaysia. The present study aims to assess the antioxidative
potential and total phenolic content of P. ostreatus aqueous extract. The antioxidant activities were evaluated against DPPH and ABTS radical-scavenging activity,
ferric-reducing antioxidant power (FRAP) and β-carotene-linoleate bleaching assay, and the Folin-Ciocalteu method for total phenolic content (TPC). The DPPH and ABTS radical-scavenging activity was found to be 63.20% and 87.29% respectively; antioxidant activity using FRAP at 1.45 mM FE/100g and β-carotenelinoleate
bleaching assay was 83.51%, while the TPC was found to be 798.55 mg GAE/100g. These antioxidant activities were compared to synthetic antioxidant, BHA and ascorbic acid. Ascorbic acid showed highest scavenging effects on
DPPH and ABTS radical, followed by P. ostreatus and BHA (at maximum safety limit). The ferric reducing power of P. ostreatus was significantly higher than
BHA and ascorbic acid. The antioxidant activity as assessed in β-carotene-linoleate bleaching assay was found to be higher in BHA compared to P. ostreatus. The
aqueous extract of P. ostreatus was found to respond differently in antioxidant assays. The antioxidative activity of the aqueous extract of P. ostreatus correlated
with its total phenolic content. Generally, the antioxidant activities of P. ostreatus’
aqueous extract are comparable to that of BHA and ascorbic acid to a certain extent.
3.Analysis of loss of heterozygosity on chromosome 16 in medulloblastomas.
Xiao-lu YIN ; Chung-sean PANG ; Ho-keung NG
Chinese Journal of Pathology 2005;34(5):305-306
Adolescent
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Adult
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Aged
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Cerebellar Neoplasms
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genetics
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Child
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Child, Preschool
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Chromosomes, Human, Pair 16
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Female
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Humans
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Loss of Heterozygosity
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Male
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Medulloblastoma
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genetics
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Middle Aged
4.Challenges of dengue control.
Annals of the Academy of Medicine, Singapore 2013;42(12):696-697
5.Immunohistochemical Study of p53 Expression in Premalignant and Malignant Cervical Neoplasms
Tan GC ; Sharifah NA ; Salwati S ; Shiran MS ; Hatta AZ ; Ng HO
Medicine and Health 2007;2(2):125-132
One of the most important cervical cancer risk factors is human papillomavirus (HPV)
infection. The p53 gene is one of the most important targets of the HPV E6 gene. E6
protein has the ability to stimulate p53 degradation, inhibits several functions of wild-type
p53 and it competes with its function including suppression of malignant growth. The aim
of this study is to determine the differences in p53 expressions in pre-malignant and
malignant cervical neoplasms. This is a retrospective study on 100 cases of cervical neoplasms. There were 21 cases of CIN 1, 8 cases of CIN 2, 25 cases of CIN 3, 36 cases
of squamous cell carcinoma, 7 cases of adenocarcinoma and 3 cases of adenosquamous
carcinoma. All cases were evaluated by immunohistochemistry using p53 monoclonal
antibody. Thirty six of the 54 pre-malignant cases (66.7%) were positive for p53 protein, in
contrast to the malignant cases in which, 40 of the 46 cases (87.0%) were positive. The
majority of CIN showed absent to focal staining (29/54, 53.7%). In contrast, 84.8% (39/46)
of the invasive carcinoma showed regional to diffuse staining. The expression of p53 is
greater in the malignant cervical neoplasms than the pre-malignant cervical lesions,
suggesting that p53 overexpression is not an early phenomenon in the pathogenesis of
cervical cancer. It is also shown to be slightly higher in percentage in CIN 2 and 3 when
compared with CIN 1. However, a number of cases were p53 negative, suggesting that
other factors may be involved and further HPV studies are indicated.
6.Asian Men’s Health: Gender Disparity and Life Expectancy
Christopher Ho CK ; Teo CH ; Ng CJ ; Zulkifli MZ ; Tan MH
Journal of Surgical Academia 2014;4(2):5-8
The aim of this review was to analyze the gender disparities found as well as the life expectancies in Asia. An
analysis of the data on gender disparities as well as life expectancies of the different Asian countries was done based
on the World Health Organization (WHO) Global Health Observatory Data Repository as well as the regional
government databases. Middle Eastern countries have the highest male to female population ratio. The results show
that in terms of population pyramid, Asia is moving towards a more geriatric population. Qatar has the highest life
expectancy for men and is the only country in Asia where men live longer than women (difference of 2 years). In
general, women in Asia live longer than men. High income countries like Hong Kong, Japan and Singapore have
higher life expectancies as compared to those on the lower income nations. The life expectancy of Asian men still
lags women. Men’s health care needs to be addressed urgently. The disparity in income-status reflecting the lifespan
of men is an impetus for us to narrow the gap of health in Asian countries.
7.Developing the "NUS Tummy Dummy", a low-cost simulator to teach medical students to perform the abdominal examination.
Shariff MAHABOOB ; Lian-Kiat LIM ; Chew-Lip NG ; Quan-Yao HO ; Michael E L LEOW ; Erle C H LIM
Annals of the Academy of Medicine, Singapore 2010;39(2):150-151
Abdomen
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physiology
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Humans
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Manikins
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Physical Examination
;
methods
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Singapore
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Students, Medical
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Teaching
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methods
9.Different hypermethylation status of RASSF1A in medulloblastoma and supratentorial primitive neuroectodermal tumor.
Chinese Journal of Pathology 2007;36(1):24-28
OBJECTIVETo investigate the epigenetic involvement of RASSF1A in intracranial primitive neuroectodermal tumors (PNETs) and compare the methylation patterns between medulloblastoma (MBs) and supratentorial PNETs (SPNETs).
METHODSThe methylation status at the promoter regions of RASSF1A was examined by methylation-specific polymerase chain reaction (MSP) in a cohort of 25 primary MBs, 9 primary SPNETs, 3 MB and 2 SPNET cell lines. RASSF1A-deficient PNET cell lines were treated with 5-aza-2'deoxycytidine, a demethylating agent, to explore the relationship between hypermethylation and the gene expression.
RESULTSThe results revealed no promoter hypermethylation of RASSF1A in 2 normal cerebellar and 5 normal cerebral tissue specimens examined. In contrast, promoter hypermethylation of RASSF1A was detected in 100% (25/25) of primary MBs, 6/9 of primary SPNETs, and all PNET cell lines. These results demonstrated that such epigenetic alteration was tumor-specific. The frequency of hypermethylation of RASSF1A in SPNETs was also found to be significantly lower than that in MBs (Fisher's exact test, P = 0.014). Treatment of RASSF1A-deficient PNET cell lines with 5-aza-2'deoxycytidine restored RASSF1A expression, providing evidence that promoter hypermethylation contributes to transcriptional silencing.
CONCLUSIONSThese results demonstrate that RASSF1A plays an important role in the development of intracranial PNETs. Different hypermethylation status of RASSF1A are found in PNET subtypes suggesting that MBs and SPNETs are epigenetical distinct tumors.
Adolescent ; Adult ; Aged ; Brain Neoplasms ; genetics ; pathology ; Cell Line, Tumor ; Cerebellar Neoplasms ; genetics ; pathology ; Child ; Child, Preschool ; DNA Methylation ; Female ; Gene Expression Regulation, Neoplastic ; Gene Silencing ; HeLa Cells ; Humans ; Infant ; Male ; Medulloblastoma ; genetics ; pathology ; Neuroectodermal Tumors, Primitive ; genetics ; pathology ; Promoter Regions, Genetic ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Tumor Suppressor Proteins ; genetics ; Young Adult
10.Molecular genetic studies on ganglioglioma.
Chinese Journal of Pathology 2005;34(3):147-149
OBJECTIVETo study the genetic alterations of ganglioglioma through the entire genome, and to investigate the pathogenesis of this neoplasm.
METHODSComparative genomic hybridization was used to provide an overview of genetic abnormalities in gangliogliomas.
RESULTSFive cases of gangliogliomas, including 3 males and 2 females, were studied genetically. Loss of genetic materials on the short arm of chromosome 9(9p) was a common genetic alteration found in 3 of 5 cases. Overrepresentation of chromosome 7 was another recurrent chromosomal imbalance, which was further confirmed by fluorescence in situ hybridization. Immunohistochemical analysis was performed on epidermal growth factor receptor (EGFR), which was located on 7p11-p13. All five cases revealed no abnormal expression of EGFR. On the other hand, genetic imbalances were also involved in multiple chromosomes including 2q33-q34, 8q12-q22, 14q21-qter, 15q26-qter and Y.
CONCLUSIONLoss of genetic materials on chromosome 9p and gain on chromosome 7 may be associated with the pathogenesis of this neoplasm.
Adolescent ; Adult ; Brain Neoplasms ; genetics ; metabolism ; Chromosome Aberrations ; Chromosome Deletion ; Chromosomes, Human, Pair 7 ; Chromosomes, Human, Pair 9 ; Female ; Follow-Up Studies ; Ganglioglioma ; genetics ; metabolism ; Humans ; In Situ Hybridization, Fluorescence ; Male ; Nucleic Acid Hybridization ; Receptor, Epidermal Growth Factor ; metabolism