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Anticoagulant activity of heat-unmasked antiphospholipid autoantibody in normal human plasma?

Ismail R, Cheng HM

Thromb Res, 1994 Jan 15;73(2):143-7.
PMID: 8171414 DOI: 10.1016/0049-3848(94)90090-6
Fulltext Antiphospholipid antibodies and stroke in the young--a study of three cases

Lee MK, Cheng HM, Ng SC, Menaka N, Tan CT, Wang F

Med J Malaysia, 1993 Sep;48(3):330-5.
PMID: 8183147

Cerebral infarction in the young is likely to be non-atheromatous. While in previous studies no cause has been found in 40% to 50% of patients, an increasing role for haemorheological factors is becoming apparent. Among these, an association between antiphospholipid antibodies (aPLs) and ischaemic cerebrovascular disease is now well-recognised. This entity has not been previously reported in Malaysian patients. In a study of 80 patients with stroke below the age of 50 years who were seen at the University Hospital, Kuala Lumpur, between January 1982 and May 1992, 3 patients with ischaemic cerebral infarction were found to have aPLs. aPLs was detected using ELISA method for anticardiolipin antibodies (aCLs), and presence of lupus anticoagulant (LA) was established by kaolin clotting time, thromboplastin inhibition test and platelet neutralisation procedure. Only 1 patient had active systemic lupus erythematous. Cerebrovascular events were recurrent in one of the 2 non-lupus patients. aPL-related stroke should be considered in young patients who have cerebral ischaemia occurring without obvious cause. More cases are likely to emerge in Malaysia with active screening.
Postprandial metabolic fate of tocotrienol-rich vitamin E differs significantly from that of alpha-tocopherol

Fairus S, Nor RM, Cheng HM, Sundram K

Am J Clin Nutr, 2006 Oct;84(4):835-42.
PMID: 17023711

BACKGROUND: The detection of tocotrienols in human plasma has proven elusive, and it is hypothesized that they are rapidly assimilated and redistributed in various mammalian tissues.
OBJECTIVE: The primary study objective was to evaluate the postprandial fate of tocotrienols and alpha-tocopherol in human plasma and lipoproteins.
DESIGN: Seven healthy volunteers (4 males, 3 females) were administered a single dose of vitamin E [1011 mg palm tocotrienol-rich fraction (TRF) or 1074 mg alpha-tocopherol] after a 7-d conditioning period with a tocotrienol-free diet. Blood was sampled at baseline (fasted) and 2, 4, 5, 6, 8, and 24 h after supplementation. Concentrations of tocopherol and tocotrienol isomers in plasma, triacylglycerol-rich particles (TRPs), LDLs, and HDLs were measured at each interval.
RESULTS: After intervention with TRF, plasma tocotrienols peaked at 4 h (4.79 +/- 1.2 microg/mL), whereas alpha-tocopherol peaked at 6 h (13.46 +/- 1.68 microg/mL). Although tocotrienols were similarly detected in TRPs, LDLs, and HDLs, tocotrienol concentrations were significantly lower than alpha-tocopherol concentrations. In comparison, plasma alpha-tocopherol peaked at 8 h (24.3 +/- 5.22 microg/mL) during the alpha-tocopherol treatment and emerged as the major vitamin E isomer detected in plasma and lipoproteins during both the TRF and the alpha-tocopherol treatments.
CONCLUSIONS: Tocotrienols are detected in postprandial plasma, albeit in significantly lower concentrations than is alpha-tocopherol. This finding confirms previous observations that, in the fasted state, tocotrienols are not detected in plasma. Tocotrienol transport in lipoproteins appears to follow complex biochemically mediated pathways within the lipoprotein cascade.
Oxidized LDL, placental trophoblast and B2-glycoprotein I

Cheng HM, Chamley LW

Proc. Soc. Exp. Biol. Med., 1998 Sep;218(4):277.
PMID: 9714070
Phenylacetic acids were detected in the plasma and urine of rats administered with low-dose mulberry leaf extract

Lee CY, Sim SM, Cheng HM

Nutr Res, 2008 Aug;28(8):555-63.
PMID: 19083460 DOI: 10.1016/j.nutres.2008.05.001

The use of a high quercetin dose to demonstrate its absorption and bioavailability does not reflect the real dietary situation because quercetin glycosides are usually present in small amounts in the human diet. This study aimed to demonstrate the absorption and bioavailability of quercetin in mulberry leaves that represents a more physiologic dietary situation. Mulberry leaf ethanol extract was prepared similar to tea infusion, which is the way the tea leaves are generally prepared for consumption. Accordingly, rats were fed by oral intubation the mulberry leaf ethanol extract (15 g%/rat per day) or pure rutin (135 microg/rat per day) for 2 weeks. The control group received a similar volume of the vehicle, 10% ethanol. There was a significant increase in total antioxidant activity (TAA) in the urine and feces of the antioxidants-fed rats. Phenylacetic acid, a microbial metabolite of quercetin, was detected in the urine of the test animals, and quercetin was present in the fecal samples. By using an in situ intestinal preparation, 3-hydroxyphenylacetic acid, another microbial metabolite of quercetin, was detected in the plasma when the duodenal segment was instilled with 2 mg of rutin. This microbial metabolite retained 50% of the TAA of quercetin. The results of this study indicate that in a more realistic dietary situation, an increase in TAA in the body after consumption of quercetin-containing foods is contributed mainly by the microbial metabolites.
Fulltext Alpha-tocotrienol is the most abundant tocotrienol isomer circulated in plasma and lipoproteins after postprandial tocotrienol-rich vitamin E supplementation

Fairus S, Nor RM, Cheng HM, Sundram K

Nutr J, 2012;11:5.
PMID: 22252050 DOI: 10.1186/1475-2891-11-5

Tocotrienols (T3) and tocopherols (T), both members of the natural vitamin E family have unique biological functions in humans. T3 are detected in circulating human plasma and lipoproteins, although at concentrations significantly lower than α-tocopherol (α-T). T3, especially α-T3 is known to be neuropotective at nanomolar concentrations and this study evaluated the postprandial fate of T3 and α-T in plasma and lipoproteins.
Fulltext Prooxidant/antioxidant ratio (ProAntidex) as a better index of net free radical scavenging potential

Ling LT, Palanisamy UD, Cheng HM

Molecules, 2010 Nov;15(11):7884-92.
PMID: 21060296 DOI: 10.3390/molecules15117884

The antioxidant activity of several Malaysian plant extracts was analyzed simultaneously with their pro-oxidant capacity. This ratio represents an index (ProAntidex) of the net free radical scavenging ability of whole plant extracts. We observed that ethanolic extracts of Nephelium lappaceum peel, Fragaria x ananassa leaf, Lawsonia inermis leaf, Syzygium aqueum leaf and grape seed had a lower Pro-Antidex than the commercially available Emblica™ extract which is an antioxidant agent with very low pro-oxidant activity. Among the aqueous extracts, Lawsonia inermis leaf, Nephelium mutobile leaf and grape seed had lower pro-oxidant activity compared to the Emblica™ extract. Among these extracts, aqueous extract of Nephelium mutobile leaf had a very low index of 0.05 compared to 0.69 for Emblica™. Most of the extracts had a far lower ProAntidex compared to the Vitamin C. The index enables us to identify extracts with high net free radical scavenging activity potential. The ProAntidex is beneficial as a screening parameter to the food industries and healthcare.
Fulltext Assessment of antioxidant capacity and cytotoxicity of selected Malaysian plants

Ling LT, Radhakrishnan AK, Subramaniam T, Cheng HM, Palanisamy UD

Molecules, 2010 Apr;15(4):2139-51.
PMID: 20428033 DOI: 10.3390/molecules15042139

Thirteen Malaysian plants; Artocarpus champeden, Azadirachta indica, Fragaria x ananassa, Garcinia mangostana, Lawsonia inermis, Mangifera indica, Nephelium lappaceum, Nephelium mutobile, Peltophorum pterocarpum, Psidium guajava and Syzygium aqueum, selected for their use in traditional medicine, were subjected to a variety of assays. Antioxidant capability, total phenolic content, elemental composition, as well as it cytotoxity to several cell lines of the aqueous and ethanolic extracts from different parts of these selected Malaysian plants were determined. In general, the ethanolic extracts were better free radical scavengers than the aqueous extracts and some of the tested extracts were even more potent than a commercial grape seed preparation. Similar results were seen in the lipid peroxidation inhibition studies. Our findings also showed a strong correlation of antioxidant activity with the total phenolic content. These extracts when tested for its heavy metals content, were found to be below permissible value for nutraceutical application. In addition, most of the extracts were found not cytotoxic to 3T3 and 4T1 cells at concentrations as high as 100 microg/mL. We conclude that although traditionally these plants are used in the aqueous form, its commercial preparation could be achieved using ethanol since a high total phenolic content and antioxidant activity is associated with this method of preparation.
Singing and learning physiology

Cheng HM

Med Teach, 2010 Jan;32(1):91-2.
PMID: 20104662
Palm olein and olive oil cause a higher increase in postprandial lipemia compared with lard but had no effect on plasma glucose, insulin and adipocytokines

Teng KT, Nagapan G, Cheng HM, Nesaretnam K

Lipids, 2011 Apr;46(4):381-8.
PMID: 21197586 DOI: 10.1007/s11745-010-3516-y

Postprandial lipemia impairs insulin sensitivity and triggers the pro-inflammatory state which may lead to the progression of cardiovascular diseases. A randomized, crossover single-blind study (n = 10 healthy men) was designed to compare the effects of a high-fat load (50 g fat), rich in palmitic acid from both plant (palm olein) or animal source (lard) versus an oleic acid-rich fat (virgin olive oil) on lipemia, plasma glucose, insulin and adipocytokines. Serum triacylglycerol (TAG) concentrations were significantly lower after the lard meal than after the olive oil and palm olein meals (meal effect P = 0.003; time effect P < 0.001). The greater reduction in the plasma non-esterified free fatty acids levels in the lard group compared to the olive oil meal was mirrored by the changes observed for serum TAG levels (P < 0.05). The magnitude of response for plasma glucose, insulin and adipocytokines [interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and leptin] were not altered by the type of dietary fats. A significant difference in plasma IL-1β was found over time following the three high fat loads (time effect P = 0.036). The physical characteristics and changes in TAG structure of lard may contribute to the smaller increase in postprandial lipemia compared with palm olein. A high fat load but not the type of fats influences concentrations of plasma IL-1β over time but had no effect on other pro-inflammatory markers tested in the postprandial state.
Effects of partially hydrogenated, semi-saturated, and high oleate vegetable oils on inflammatory markers and lipids

Teng KT, Voon PT, Cheng HM, Nesaretnam K

Lipids, 2010 May;45(5):385-92.
PMID: 20437207 DOI: 10.1007/s11745-010-3416-1

Knowledge about the effects of dietary fats on subclinical inflammation and cardiovascular disease risk are mainly derived from studies conducted in Western populations. Little information is available on South East Asian countries. This current study investigated the chronic effects on serum inflammatory markers, lipids, and lipoproteins of three vegetable oils. Healthy, normolipidemic subjects (n = 41; 33 females, 8 males) completed a randomized, single-blind, crossover study. The subjects consumed high oleic palm olein (HOPO diet: 15% of energy 18:1n-9, 9% of energy 16:0), partially hydrogenated soybean oil (PHSO diet: 7% of energy 18:1n-9, 10% of energy 18:1 trans) and an unhydrogenated palm stearin (PST diet: 11% of energy 18:1n-9, 14% of energy 16:0). Each dietary period lasted 5 weeks with a 7 days washout period. The PHSO diet significantly increased serum concentrations of high sensitivity C-reactive protein compared to HOPO and PST diets (by 26, 23%, respectively; P < 0.05 for both) and significantly decreased interleukin-8 (IL-8) compared to PST diet (by 12%; P < 0.05). In particular PHSO diet, and also PST diet, significantly increased total:HDL cholesterol ratio compared to HOPO diet (by 23, 13%, respectively; P < 0.05), with the PST diet having a lesser effect than the PHSO diet (by 8%; P < 0.05). The use of vegetable oils in their natural state might be preferred over one that undergoes the process of hydrogenation in modulating blood lipids and inflammation.
Tocotrienols suppress proinflammatory markers and cyclooxygenase-2 expression in RAW264.7 macrophages

Yam ML, Abdul Hafid SR, Cheng HM, Nesaretnam K

Lipids, 2009 Sep;44(9):787-97.
PMID: 19655189 DOI: 10.1007/s11745-009-3326-2

Tocotrienols are powerful chain breaking antioxidant. Moreover, they are now known to exhibit various non-antioxidant properties such as anti-cancer, neuroprotective and hypocholesterolemic functions. This study was undertaken to investigate the anti-inflammatory effects of tocotrienol-rich fraction (TRF) and individual tocotrienol isoforms namely delta-, gamma-, and alpha-tocotrienol on lipopolysaccharide-stimulated RAW264.7 macrophages. The widely studied vitamin E form, alpha-tocopherol, was used as comparison. Stimulation of RAW264.7 with lipopolysaccharide induced the release of various inflammatory markers. 10 mcirog/ml of TRF and all tocotrienol isoforms significantly inhibited the production of interleukin-6 and nitric oxide. However, only alpha-tocotrienol demonstrated a significant effect in lowering tumor necrosis factor-alpha production. Besides, TRF and all tocotrienol isoforms except gamma-tocotrienol reduced prostaglandin E(2) release. It was accompanied by the down-regulation of cyclooxygenase-2 gene expression by all vitamin E forms except alpha-tocopherol. Collectively, the data suggested that tocotrienols are better anti-inflammatory agents than alpha-tocopherol and the most effective form is delta-tocotrienol.
Screening for nasopharyngeal carcinoma with an ELISA using the Epstein-Barr virus nuclear antigen, EBNA 1: a complementary test to the IgA/VCA immunofluorescence assay

Cheng HM, Foong YT, Mathew A, Sam CK, Dillner J, Prasad U

J Virol Methods, 1993 Apr;42(1):45-51.
PMID: 7686558

An ELISA using the Epstein-Barr virus nuclear antigen 1 (EBNA 1) was found to detect selectively specific IgA in sera from patients with nasopharyngeal carcinoma (NPC). The antigen, p107, was a 20-amino acid synthetic peptide, representing a major epitope of EBNA 1.267/294 (90.8%) of NPC patients had IgA antibodies to p107 but in normal individuals, only 41/577 (7.1%) had IgA/p107. In sera from patients with other cancers, 11/77 (14.3%) had IgA/p107 reactivity. 124 IgA/VCA positive and 86 IgA/VCA negative NPC sera were also tested for IgA/p107 binding in ELISA. The majority of IgA/VCA positive sera (117) also contained IgA/p107 antibodies. Of interest was the detection of 74/86 IgA/p107 reactive sera in the IgA/VCA negative group. The results suggest that the IgA/p107 ELISA could become a useful, complementary screening assay to the IgA/VCA immunofluorescence test for detection of NPC.
Improved sensitivity of detection by avidin-biotin complex (ABC) immunocytochemistry in Epstein-Barr virus serology

Thoe SY, Sam CK, Cheng HM, Prasad U

J Med Virol, 1989 Dec;29(4):311-4.
PMID: 2559955

Serum antibodies against Epstein-Barr virus (EBV)-determined antigens have traditionally been titrated by the indirect immunofluorescence (IIF) technique. The avidin-biotin complex (ABC) immunocytochemical technique was used to determine the serum levels of IgA against EBV viral capsid antigen (IgA/VCA) and IgA against EBV early antigen (IgA/EA) in sera of 106 nasopharyngeal carcinoma (NPC) patients prior to treatment and 100 normal individuals. The sensitivity of the ABC technique is enhanced by an amplification of the antigen-antibody reaction, which involves the binding of the enzyme-linked ABC to the second biotinylated antibody. There was a good correlation (r = 0.9988) between ABC and IIF-determined IgA/VCA-positive titres, with the ABC technique being more sensitive than IIF in the detection of IgA/VCA in NPC sera: 94% (99/106) and 76% (80/106), respectively. The frequency of IgA/EA reactivity in NPC sera was also markedly increased by immunodetection with the ABC technique as compared with IIF technique: 63% (69/106) and 28% (30/106) respectively. Both the immunocytochemical techniques were equally specific in discriminating between elevated serum titres of IgA/VCA and IgA/EA in NPC sera from normal human sera.
Antioxidant status following postprandial challenge of two different doses of tocopherols and tocotrienols

Fairus S, Cheng HM, Sundram K

J Integr Med, 2020 Jan;18(1):68-79.
PMID: 31812339 DOI: 10.1016/j.joim.2019.11.005

OBJECTIVE: Tocotrienols (T3s) have been hypothesized to have greater antioxidant capacity than tocopherols (Ts) due to differences in biokinetics that affect their absorption and function. The present trial compares the antioxidant effectiveness following postprandial challenge of two different doses of α-T or palm T3-rich fraction (TRF) treatments and evaluates their dose-response effects on antioxidant status.
METHODS: Ten healthy volunteers were given four different doses of vitamin E formulations (268 mg α-T, 537 mg α-T, 263 mg TRF or 526 mg TRF) in a cross-over postprandial trial. Blood was sampled at 0, 2, 4, 5, 6 and 8 hours after meal consumption and plasma antioxidant status including total glutathione, superoxide dismutase, malondialdehyde (MDA), ferric reducing antioxidant potential and trolox-equivalent antioxidant capacity, was analyzed.
RESULTS: Supplementation with the different doses of either α-T or TRF did not significantly improve overall antioxidant status. There was no significant difference in overall antioxidant status among treatments at the different doses compared. However, a significant dose-response effect was observed for plasma MDA throughout the 8-hour postprandial period. MDA was significantly lower after the 537 mg α-T treatment, compared to the 268 mg α-T treatment; it was also lower after the 526 mg TRF treatment compared to the 263 mg TRF treatment (P
Heat inactivation of serum potentiates anti-cardiolipin antibody binding in ELISA

Cheng HM, Ngeow YF, Sam CK

J Immunol Methods, 1989 Nov 30;124(2):235-8.
PMID: 2600427

Heat treatment of sera at 56 degrees C for 30 min results in positive ELISA reactions for anti-cardiolipin antibody (aCL) in sera that had undetectable or low levels of aCL before heat inactivation. The positive, potentiated reactivity of the heated sera in the aCL ELISA could be inhibited with the cardiolipin antigen and was abolished by prior IgG depletion using staphylococcal protein A. The heat-potentiating effect of aCL binding in ELISA was evident in both normal human sera and clinical sera including sera from patients with systemic lupus erythematosus and syphilis.
Fulltext Isolated systolic hypertension in Asia

Tsai TY, Cheng HM, Chuang SY, Chia YC, Soenarta AA, Minh HV, et al.

J Clin Hypertens (Greenwich), 2021 03;23(3):467-474.
PMID: 33249701 DOI: 10.1111/jch.14111

Isolated systolic hypertension (ISH) is the most common type of essential hypertension in the elderly and young adults. With rapid industrialization and population aging, the prevalence of ISH in Asia will rise substantially. Asian populations have distinct epidemiological features, risk factors and are especially vulnerable to ISH. There is a pressing need for Asian countries to formulate their unique strategies for control of ISH. In this review, we focus on the (1) epidemiology and pathophysiology, (2) risk factors and impact on outcomes, and (3) treatment goal and strategy for ISH in Asia.
Fulltext Mental health problems and hypertension in the elderly: Review from the HOPE Asia Network

Turana Y, Tengkawan J, Chia YC, Shin J, Chen CH, Park S, et al.

J Clin Hypertens (Greenwich), 2021 Mar;23(3):504-512.
PMID: 33283971 DOI: 10.1111/jch.14121

The "triple burden" of aging population, hypertension, and mental health problems making elderly in Asia is more vulnerable. There is evidence of a bidirectional relationship between mental health and hypertension, which results in lower quality of life, lower rate of treatment adherence, and higher mortality among elderly individuals. It is essential to overcome known barriers and care for the elderly with high-risk factors in order to address these burdens. This review revealed that elderly with hypertension were more likely to suffer from depression and anxiety. Therefore, debunking myths, creating awareness regarding mental health, and increasing access to mental health resources through holistic community-based programs would greatly reduce such problems and optimize the chances of success in controlling hypertension-related problems.
Fulltext Angiotensin receptor neprilysin inhibitor as a novel antihypertensive drug: Evidence from Asia and around the globe

Lin DS, Wang TD, Buranakitjaroen P, Chen CH, Cheng HM, Chia YC, et al.

J Clin Hypertens (Greenwich), 2021 03;23(3):556-567.
PMID: 33305531 DOI: 10.1111/jch.14120

Hypertension is a worldwide epidemic that continues to grow, with a subset of patients responding poorly to current treatment available. This is especially relevant in Asia, which constitutes 61% of the global population. Hypertension in Asia is a unique entity that is often salt-sensitive, nocturnal, and systolic predominant. Sacubitril/valsartan is a first-in-class angiotensin receptor neprilysin inhibitor that was first used in heart failure with reduced ejection fraction. Sacubitril inhibits neprilysin, a metallopeptidase that degrades natriuretic peptides (NPs). NPs exert sympatholytic, diuretic, natriuretic, vasodilatory, and insulin-sensitizing effects mostly via cyclic guanosine monophosphate (cGMP)-mediated pathways. As an antihypertensive agent, sacubitril/valsartan has outperformed angiotensin II receptor type 1 blockers (ARBs), with additional reductions of office systolic blood pressures ranging between 5 and 7 mmHg, in multiple studies in Asia and around the globe. The drug was well tolerated even in the elderly or those with chronic kidney disease. Its mechanisms of actions are particularly attractive for treatment of hypertension in Asia. Sacubitril/valsartan offers a novel, dual class, single-molecule property that may be considered as first-line antihypertensive therapy. Further investigations are needed to validate its safety for long-term use and to explore other potentials such as in the management of insulin resistance and obesity, which often coexist with hypertension in Asia.
Fulltext Hypertension and erectile dysfunction: The role of endovascular therapy in Asia

Wang TD, Lee CK, Chia YC, Tsoi K, Buranakitjaroen P, Chen CH, et al.

J Clin Hypertens (Greenwich), 2021 03;23(3):481-488.
PMID: 33314715 DOI: 10.1111/jch.14123

The prevalence of erectile dysfunction (ED) is above 40% in both Asian and non-Asian male populations after the age of 40 years. The prevalence of ED among hypertensive patients is approximately double than that in normotensive population. Pelvic arterial insufficiency is the predominant cause of ED in men aged over 50 years. Stenosis in any segment of the iliac-pudendal-penile arterial system, which is considered an erectile-related arterial axis, could lead to ED. Pharmacotherapy with lifestyle modification is effective in alleviating sexual dysfunction, yet a substantial number of patients still develop ED. Given the established applicability of angioplasty for the entire iliac-pudendal-penile arterial system, penile duplex ultrasound, and pelvic computed tomography angiography could be considered as the routine screening tools in ED patients with poor response to phosphodiesterase-5 inhibitors. Endovascular therapy for pelvic arterial insufficiency-related ED has been shown to be a safe and effective treatment option in patients who have anatomically suitable vessels and functionally significant stenoses. Clinical improvement was achieved in over 60% of patients at one year following pelvic angioplasty in the PERFECT registry from Taiwan. A 30%-40% restenosis rate in distal internal pudendal and penile arteries remains a hurdle. Angioplasty for pelvic arterial occlusive disease could be considered as a viable approach to arteriogenic ED.

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