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Fulltext Glycyrrhizic acid improved lipoprotein lipase expression, insulin sensitivity, serum lipid and lipid deposition in high-fat diet-induced obese rats

Eu CH, Lim WY, Ton SH, bin Abdul Kadir K

Lipids Health Dis, 2010;9:81.
PMID: 20670429 DOI: 10.1186/1476-511X-9-81

The metabolic syndrome, known also as the insulin resistance syndrome, refers to the clustering of several risk factors for atherosclerotic cardiovascular disease. Dyslipidaemia is a hallmark of the syndrome and is associated with a whole body reduction in the activity of lipoprotein lipase (LPL), an enzyme under the regulation of the class of nuclear receptors known as peroxisome proliferator-activated receptor (PPAR). Glycyrrhizic acid (GA), a triterpenoid saponin, is the primary bioactive constituent of the roots of the shrub Glycyrrhiza glabra. Studies have indicated that triterpenoids could act as PPAR agonists and GA is therefore postulated to restore LPL expression in the insulin resistant state.
Fulltext Comparison of PCR-based genotyping methods for hepatitis B virus

Lim CK, Tan JT, Ravichandran A, Chan YC, Ton SH

Malays J Pathol, 2007 Dec;29(2):79-90.
PMID: 19108399 MyJurnal

Hepatitis B virus (HBV) is classified into eight genotypes (A to H). In this study, three genotyping methods were compared for their sensitivity and accuracy, namely PCR-RFLP on the S region, PCR-RFLP on the pre-S region and nested PCR with type specific primers. Sixty HBV samples from infected sera were genotyped. The nested PCR with type specific primers was found to be the most sensitive and produced substantial numbers of co-infections by genotypes B and C. The sensitivities for both PCR-RFLP methods were lower and did not reveal co-infections. Generally, the three methods produced consistent genotyping results in samples infected by single genotypes but for co-infections by genotypes B and C, the two PCR-RFLP methods yielded only single genotypic results. For the cases of single genotypic infections, genotypes ascertained by sequencing were in concordance across all three methods. However, when co-infections occurred, PCR analysis on clones revealed only single genotypic infections.
Correlations of HBV genotypes, mutations affecting HBeAg expression and HBeAg/ anti-HBe status in HBV carriers

Lim CK, Tan JT, Khoo JB, Ravichandran A, Low HM, Chan YC, et al.

Int J Med Sci, 2006;3(1):14-20.
PMID: 16421626

This study was carried out to determine the effects of hepatitis B virus genotypes, core promoter mutations (A1762G1764-->T1762A1764) as well as precore stop codon mutations (TGG-->TAG) on HBeAg expression and HBeAg/ anti-HBe status. Study was also performed on the effects of codon 15 variants (C1858/ T1858) on the predisposition of precore stop codon mutations (TGG-->TAG). A total of 77 sera samples were analyzed. Fifty one samples were successfully genotyped of which the predominant genotype was genotype B (29/ 51, 56.9 %), followed by genotype C (16/ 51, 31.4 %). Co-infections by genotypes B and C were observed in four samples (7.8 %). To a lesser degree, genotypes D and E (2.0 % each) were also observed. For core promoter mutations, the prevalence was 68.8 % (53/ 77) for A1762G1764 wild-type and 14.3 % (11/ 77) for T1762A1764 mutant while 9.1 % (7/ 77) was co-infected by both strains. The prevalence of codon 15 variants was found to be 42.9 % (33/ 77) for T1858 variant and 16.9 % (13/ 77) for C1858 variant. No TAG mutation was found. In our study, no associations were found between genotypes (B and C) and core promoter mutations as well as codon 15 variants. Also no correlation was observed between HBeAg/ anti-HBe status with genotypes (B and C) and core promoter mutations.
The distribution of immunoregulatory cells in the peripheral blood of normal Malaysian adults

Chin SF, Cheong SK, Lim YC, Ton SH

Malays J Pathol, 1993 Jun;15(1):49-52.
PMID: 8277790

The distribution of immunoregulatory cells in the peripheral blood of an individual has now been established as an important tool in helping the management of several diseases. It is necessary to set the normal ranges of these cells for the laboratory. We have undertaken in this study to establish the reference ranges for normal Malaysian adults. We found that the mean percentages of T cells, B cells, T Helper cells (CD4), T suppressor cells (CD8), NK cells and the ratio of CD4/CD8 were 70.91%, 11.38%, 38.15%, 37.76%, 17.45%, and 1.00 respectively. There was no significant difference between the sexes. In certain parameters, there was significant differences between Malay, Chinese and Indians. The Chinese and Indians were significantly different in the distribution of B cells and in the CD4/CD8 ratio. In the case of CD4 and NK cells, the Indians were different from the other two groups.
Isolation of human surfactant protein A from amniotic fluid

Cheong KB, Cheong SK, Boo NY, Jemilah M, Ton SH

Malays J Pathol, 1995 Dec;17(2):97-101.
PMID: 8935134

Surfactant protein A (SP-A) is one of the four known surfactant-associated proteins found in human lungs. It plays a major role in determining regulation of surfactant uptake and resecretion. Qualitative and quantitative deficiencies of SP-A may contribute to neonatal respiratory distress syndrome. The measurement of its level in amniotic fluid or neonatal tracheal aspirate may be useful in the assessment of replacement therapy using natural or synthetic surfactants. In order to develop an in-house immunoassay to detect the level of SP-A, we used a discontinuous sucrose density gradient to isolate SP-A from amniotic fluid. Polyacrylamide gel electrophoresis was carried out on the isolates with low molecular weight markers. We successfully isolated SP-A from 12 out of 31 samples of amniotic fluid. The isolates were found to be relatively pure and have a molecular weight of about 35 kD. The isolated SP-A were used as immunogens to raise antibodies in rabbits for the immunoassay.
An in-house ELISA method for measuring surfactant protein A

Cheong KB, Cheong SK, Boo NY, Jemilah M, Ton SH

Malays J Pathol, 1995 Dec;17(2):91-6.
PMID: 8935133

An in-house enzyme-linked immunoabsorbant assay (ELISA) for SP-A was successfully developed using in-house polyclonal anti SP-A and a commercial polyclonal anti-rabbit immunoglobulin horseradish peroxidase conjugate system. The standard curve, generated by using 50 ng of SP-A to coat the plate and 1:500 dilution of polyclonal anti SP-A as a primary antibody, was linear for concentrations of SP-A ranging from 4 micrograms/l to 4000 micrograms/l and reproducible. Results of recovery study of SP-A from a known sample of tracheal aspirate ranged from 94%-114%. Intra- and inter-assay coefficients of variations were 2.7% and 5.6% respectively for a known sample of tracheal aspirate. Interference study showed that tracheal aspirate did not interfere with the assay. The assay developed was intended to be used for SP-A measurement in tracheal aspirates obtained from neonates with and without respiratory distress syndrome.
Nucleotide sequence of precore region of hepatitis B virus DNA in HBsAg-positive carriers in Malaysia

Ton SH, Iskandar K, Noriah R, Thanaletchimy N

Scand. J. Infect. Dis., 1996;28(6):543-8.
PMID: 9060053

As most published studies on precore mutants have been carried out on isolates from patients with liver diseases, and it is unclear whether HBsAg carriers with viraemia in the absence of HBeAg are also generally infected by such mutants, it was decided to sequence the precore region in some HBV-DNA isolated from HBsAg-positive carriers. Precore sequences of HBV-DNA from 43 HBsAg carriers in Malaysia were studied. Three HBV subtypes were identified according to the nucleotide sequence of the precore region. Most of the carriers were found to be infected by the subtype adr. Mutations were detected in the precore regions. The most common conserved mutation was a silent mutation involving conversion from T to C (CCT to CCC) at position 1858 at codon 15 (proline). It was found that 4/43 (9.3%) had a mutation at the penultimate codon where TGG was changed to TAG. All 4 isolates with the TAG mutation had nt T at position 1858. Of the 4 carriers who were infected by these mutant viruses, 2 were coinfected with the wild type, 1 was infected only by a variant with the mutation at position 1896, while another was infected by a variant with mutations at positions 1896 and 1899. Three of the 4 were anti-HBe positive while 1 was HBeAg positive. Alanine aminotransaminase activities in all 4 carriers were normal. This study therefore demonstrated that variants with stop codons at the penultimate codon could be found in asymptomatic carriers in Malaysia.
Infectiousness of HBsAg carriers in Malaysia

Ton SH, Yeoh KS, Lim WC, Noriah R, Cheong SK, Thanaletchimy N

J Trop Med Hyg, 1995 Aug;98(4):277-80.
PMID: 7636926

HBV-DNA were analysed in 330 HBsAg-positive carriers in Malaysia by dot-blot hybridization and polymerase chain reaction. Seventy-three (22.12%) were positive for the virus. Of these, 65 (89%) were males and 8 (11%) were females. Statistically, there was no significant difference (P = 0.13). No significant decline in HBV-DNA with age in the Malay and Chinese males was observed (P = 0.2). Prevalence of HBV-DNA was higher in the Chinese carriers than in the Malay carriers for most age groups in both sexes. Sixty-one HBV-DNA-positive carriers were also positive for HBeAg. However, three individuals were positive only for anti-HBe, one was positive for both HBeAg and anti-HBe, and eight were negative for both HBeAg and anti-HBe. Fifty-seven were positive for HBeAg but negative for HBV-DNA. No relation was observed between raised alanine aminotransaminase and aspartate aminotransaminase levels and the presence of HBV-DNA (P = 0.4).
Purified ingredient-based high-fat diet is superior to chow-based equivalent in the induction of metabolic syndrome

Cheng HS, Phang SCW, Ton SH, Abdul Kadir K, Tan JBL

J Food Biochem, 2019 02;43(2):e12717.
PMID: 31353646 DOI: 10.1111/jfbc.12717

The present study aimed to outline the physiological and metabolic disparity between chow- and purified ingredient-based high-fat diets and their efficacy in the induction of metabolic syndrome (MetS). Male, 3-week-old Sprague Dawley rats were randomly assigned to chow-based control diet, chow-based high-fat diet, purified control diet, and purified high-fat diet for 12 weeks. Physical and biochemical changes were documented. Chow-based diets, irrespective of the lipid content, resulted in significantly lower weight gain and organ weight compared to purified ingredient-based diets. Circulating insulin, total proteins, albumin, and certain lipid components like the triglycerides, total cholesterol, and high-density lipoprotein-cholesterol were also lower in the chow-based diet groups. Both chow- and purified high-fat diets induced central obesity, hypertension, and hyperglycaemia, but the latter was associated with earlier onset of the metabolic aberrations and additionally, dyslipidaemia. In conclusion, purified high-fat diet is a better diet for MetS induction in rats. PRACTICAL APPLICATIONS: Modeling metabolic syndrome is commonly accomplished with the use of chow- or purified ingredient diets enriched with carbohydrates and/or lipids, but the differences and associated drawbacks are unclear. This study highlights that chow- or modified chow-based diets have a tendency to introduce unwanted metabolic changes which are inconsistent with the progression of metabolic syndrome. Thus, the use of these diets in metabolic disease study should be avoided. On the other hand, purified high-fat diet which can effectively induce the features of metabolic syndrome is highly recommended.
Pleiotropic ameliorative effects of ellagitannin geraniin against metabolic syndrome induced by high-fat diet in rats

Cheng HS, Goh BH, Phang SCW, Amanullah MM, Ton SH, Palanisamy UD, et al.

Nutrition, 2020 08 12;79-80:110973.
PMID: 32916379 DOI: 10.1016/j.nut.2020.110973

OBJECTIVES: Metabolic syndrome (MetS), a multiplex risk factor for cardiovascular disease and type 2 diabetes, is increasingly prevalent worldwide. Ellagitannin geraniin, a polyphenol found in the rind of rambutan (Nephelium lappaceum), has demonstrated therapeutic effects against metabolism dysfunction. The aim of this study was to characterize the metabolic effects and possible mechanism of geraniin in rats with MetS induced by a high-fat diet (HFD).
METHODS: MetS was induced in Sprague Dawley rats on an HFD, followed by a daily oral gavage of geraniin (25 mg/kg) for 4 wk. The outcomes of geraniin-treated rats were compared with those of untreated rats on either a control diet or an HFD and with rats with MetS treated with metformin on a daily basis (200 mg/kg).
RESULTS: The supplementation of geraniin ameliorated multiple metabolic abnormalities caused by HFD, including hypertension, impaired glucose and lipid metabolism, ectopic fat deposition in the visceral fat and liver, and disturbed antioxidant mechanism and inflammatory response. The benefits conferred by geraniin were comparable to metformin. Transcriptomic analysis revealed a profound influence of geraniin on the hepatic expression profiles. The lipid and steroid metabolic processes that were aberrantly activated by HFD were suppressed by geraniin. Based on the differential transcriptomes, geraniin also exerted a significant modulatory effect on the expression of mitochondrial genes, potentially influencing the mitochondrial activity and leading to the observed beneficial effects.
CONCLUSION: Geraniin supplementation mitigated metabolic anomalies of MetS in rats, making it an attractive drug candidate for further investigation.
Fulltext Glycyrrhizic acid can attenuate metabolic deviations caused by a high-sucrose diet without causing water retention in male Sprague-Dawley rats

Fernando HA, Chandramouli C, Rosli D, Lam YL, Yong ST, Yaw HP, et al.

Nutrients, 2014 Nov 04;6(11):4856-71.
PMID: 25375630 DOI: 10.3390/nu6114856

Glycyrrhizic acid (GA) ameliorates many components of the metabolic syndrome, but its potential therapeutic use is marred by edema caused by inhibition of renal 11β-hydroxysteroid dehydrogenase 2 (11β-HSD2). We assessed whether 100 mg/kg per day GA administered orally could promote metabolic benefits without causing edema in rats fed on a high-sucrose diet. Groups of eight male rats were fed on one of three diets for 28 days: normal diet, a high-sucrose diet, or a high-sucrose diet supplemented with GA. Rats were then culled and renal 11β-HSD2 activity, as well as serum sodium, potassium, angiotensin II and leptin levels were determined. Histological analyses were performed to assess changes in adipocyte size in visceral and subcutaneous depots, as well as hepatic and renal tissue morphology. This dosing paradigm of GA attenuated the increases in serum leptin levels and visceral, but not subcutaneous adipocyte size caused by the high-sucrose diet. Although GA decreased renal 11β-HSD2 activity, it did not affect serum electrolyte or angiotensin II levels, indicating no onset of edema. Furthermore, there were no apparent morphological changes in the liver or kidney, indicating no toxicity. In conclusion, it is possible to reap metabolic benefits of GA without edema using the current dosage and treatment time.
The insulin-sensitising properties of the ellagitannin geraniin and its metabolites from Nephelium lappaceum rind in 3T3-L1 cells

Perera A, Ton SH, Moorthy M, Palanisamy UD

Int J Food Sci Nutr, 2020 Dec;71(8):940-953.
PMID: 32319838 DOI: 10.1080/09637486.2020.1754348

In this study, the insulin-like and insulin sensitising effects of the ellagitannins geraniin, corilagin, ellagic acid, gallic acid and Nephelium lappaceum rind extract in 3T3-L1 adipocytes was investigated. It was observed that non-toxic concentrations of geraniin and its metabolites (0.2-20 μM) and N. lappaceum extract (0.2-20 μg/mL) exhibited insulin-like properties in the absence of insulin and insulin-sensitising properties in the presence of insulin particularly with regards to glucose uptake in 3T3-L1 adipocytes. The compounds were further able to promote adipocyte differentiation and may be involved in the inhibition of lipolysis in 3T3-L1 adipocytes in the presence of insulin. However further study into the molecular mechanisms of action of these compounds need to be carried out to better understand the potential of these compounds/extracts to act as therapeutic agents for hyperglycaemia associated with diabetes mellitus and obesity.
Fulltext Hepatitis B markers in heterosexuals involved in promiscuous sexual activity

Rajakumar MK, Ton SH, Lim KF, Oorloff KH

Med J Malaysia, 1984 Mar;39(1):65-8.
PMID: 6513842

179 heterosexuals, selected for VDRL testing on the basis of a history of involvement in promiscuous sexual activity, mainly prostitution, had their serum also tested for hepatitis B infection markers, HBsAg, HBeAg and anti-HBe. 51 samples (29%) were found to be positive for at least one of the three markers, at levels higher than the already high levels in voluntary random blood donors in Malaysia.
Fulltext Prevalence of hepatitis A virus infection in normal individuals and hospital patients in Kuala Lumpur

Ton SH, Thiruselvam A, Lopez CG, Noriah R

Med J Malaysia, 1983 Dec;38(4):279-81.
PMID: 6100990

110 normal, healthy adults were tested for antibody to hepatitis A (anti-HA) type IgG and 86 (78.2%) were found to be positive. An age-specific prevalence wasfound to be lowest in the lower agegroup and highest in the higher age-group. Out of 24 IgG positive individuals, only one was found to have type IgM. No significant difference in the incidence ofanti-HA type IgG was found between 42 patients in the Urology Unit, General Hospital, Kuala Lumpur and normal individuals (P > 0.1). 15 patients diagnosed as viral hepatitis were investigated for HA V IgG and IgM antibodies. 13 (86.7%) were positive for type IgG. Of this, only five (33%) were positive for the type IgM, suggesting that HA V is the cause of acute viral hepatitis in 33% of cases admitted to hospital as viral hepatitis.
HBeAG and anti-HBe in the Malaysian population and in Malaysian prisoners

Ton SH, Lopez CG, Noriah R

Southeast Asian J. Trop. Med. Public Health, 1983 Jun;14(2):252-4.
PMID: 6635764

The incidence of HBsAg in random blood donors was found to be twice that of the prisoner population. The anti-HBe however, was about twice that in the prisoners when compared with the random blood donors. Both the random blood donors and the prisoners had similar incidence of HBeAg. The percentage frequency of HBsAg positivity with anti-HBe positivity was also similar in both groups. The 18 normal non-blood donors did not have HBsAg, HBeAg or anti-HBe.
Fulltext Infectiousness with respect to HBV of medical staff and patients in the General Hospital, Kuala Lumpur

Ton SH, Lopez CG, Cheong KS, Noriah R

Singapore Med J, 1984 Aug;25(4):244-6.
PMID: 6505725

The infectiousness with regard to HBV Infection of staff and patients in various units of the General Hospital, Kuala Lumpur
was assessed. It was found that all units, with the exception of the obstetric unit, were equally high risk areas. At least 50% of the patients in all these units had one or more of the markers. Among the medical staff, the anaesthetists had the highest
incidence of HBV markers (100%) while medical officers who had worked for three years or more were more likely to have to
have the HBV markers. The degree of infectiousness of the nurses In HDU and ICU/OT was found to be similar.
Effect of age, weight, race and sex on blood pressure and erythrocyte sodium pump characteristics

Adeeb N, Ton SH, Muslim N

Clin Exp Hypertens A, 1990;12(6):1115-34.
PMID: 2173984

In order to examine whether erythrocyte membrane handling of sodium is influenced by factors other than hypertension, measurements of red cell sodium transport were studied in one hundred normotensive volunteers. Erythrocyte sodium content was found to increase with increasing age, body weight and mean arterial pressure (MAP). It is also significantly correlated with age, body weight and MAP. Total sodium efflux was found to be reduced and negatively correlated with age and body weight. A reduction in ouabain-sensitive sodium efflux was also observed with increasing age and body weight. In males, the rate of ouabain-sensitive sodium efflux is higher than in females. Race was found to have no effect on erythrocyte electrolyte content and cationic flux rates of subjects. These data suggest that when studies in hypertension are going to be carried out, control subjects carefully matched for age, body weight and sex should be used if confounding results are not to be obtained.
Fulltext A preliminary report on the relationship between serum anti-thrombin III concentration in pre- and post-operative patients and in women on oral contraceptives

Ton SH, Lopez CG, Thiruselvam A, Lyou YT

Med J Malaysia, 1981 Dec;36(4):212-4.
PMID: 7334955

A T III values in patients undergoing surgery were found to be lower post-operatively but the fall in value was not significant while women on oral contraceptives were found to have similar AT III values as that of women not on oral contraceptives. The observed values are discussed.
Fulltext The use of several markers of hepatitis B infection to monitor risks of infection in a haemodialysis unit and in laboratories

Ton SH, Lopez CG

Med J Malaysia, 1981 Dec;36(4):209-11.
PMID: 7334954
Serum ferritin concentrations in male Malaysian blood donors

Ton SH, Lopez CG

Southeast Asian J. Trop. Med. Public Health, 1980 Mar;11(1):87-90.
PMID: 7403958

Serum ferritin and haemoglobin estimates were carried out on 78 first time blood donors with a view to determining iron store status. Of these 30 were Malays, 20 were Chinese and 28 were Indians. The ferritin level in Malay donors ranged from 16-160 mg/ml (mean 83 +/- 49.4 mg/ml in chinese donors is ranged from 36-500 mg/ml (mean 242.8 +/- 132 mg/ml), and in the Indian donors it ranged from 5 - 270 mg/ml (mean 94.6 +/- 67.9 mg/ml). The haemoglobin concentration for the whole group was 14.9 +/- 1.49 g/dl. There was no correlation of haemoglobin concentration with serum ferritin levels.

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