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Comparative efficacy of perindopril and enalapril once daily using 24-hour ambulatory blood pressure monitoring

Yusoff K, Razak TA, Yusof N, Rafee NM

Int J Clin Pract, 1999 Jun;53(4):277-80.
PMID: 10563072

ACE inhibitors are important therapeutic agents in controlling hypertension, correcting some of its pathophysiological derangement and improving its prognosis. While there are many such agents, there may be some important differences between them. This placebo run-in, double blind, crossover study, using 24-hour ambulatory blood pressure monitoring, compares the efficacy of perindopril 4-8 mg and enalapril 10-20 mg as once daily antihypertensive agents on 32 patients. For diastolic blood pressure (DBP), perindopril had a placebo-corrected peak (P) reduction of blood pressure (BP) of -6.4 +/- 1.3 mmHg vs its placebo-corrected trough (T) of -5.2 +/- 1.7 mmHg. Enalapril had a reduction in DBP of -8.5 +/- 1.3 mmHg (P) and -5.7 +/- 1.7 mmHg (T). For systolic blood pressure (SBP), perindopril had a reduction of -7.5 +/- 1.6 mmHg (P) vs -7.3 +/- 2.2 mmHg (T) compared to enalapril with -10.8 +/- 1.6 mmHg (P) vs -8.3 +/- 2.3 mmHg (T). Placebo-corrected trough-to-peak ratio (SBP/DBP) for perindopril was 0.97/0.81 vs 0.77/0.67 for enalapril. There was no difference noted in 24-hour mean BP, area under the curve or post-dose casual BP measurements. Both perindopril and enalapril were well tolerated and the two treatment groups had similar safety profiles. Perindopril thus had a predictable and sustained blood pressure effect giving a 24-hour cover for the patient without excessive peak effect or poor trough effect.
Sequence and phylogenetic analysis of the fusion protein cleavage site of Newcastle disease virus field isolates from Iran

Kianizadeh M, Aini I, Omar AR, Yusoff K, Sahrabadi M, Kargar R

Acta Virol., 2002;46(4):247-51.
PMID: 12693862

Nine Newcastle disease virus (NDV) isolates from Newcastle disease (ND) outbreaks in different regions of Iran were characterized at molecular level. Sequence analysis revealed that the isolates shared two pairs of arginine and a phenylalanine at the N-terminus of the fusion (F) protein cleavage site similarly to other velogenic isolates of NDV characterized earlier. Eight of the nine isolates had the same amino acid sequence as VOL95, a Russian NDV isolate from 1995. However, one isolate, MK13 showed 5 amino acid substitutions, of which 3 have been reported for other velogenic NDV isolates. These results suggest that the origin of the outbreaks of ND in different parts of Iran in 1995-1998 is VOL95.
Novel peptides that inhibit the propagation of Newcastle disease virus

Ramanujam P, Tan WS, Nathan S, Yusoff K

Arch Virol, 2002 May;147(5):981-93.
PMID: 12021868

A disulfide constrained random heptapeptide library displayed on filamentous bacteriophage M13 was applied to select specific ligands that interact with Newcastle disease virus (NDV). A fusion phage carrying the amino acid sequence TLTTKLY was selected from the panning procedure. An antibody competition assay showed that the selected phage was capable of competing with the polyclonal antibodies raised against NDV for binding sites on the virus. Determination of the binding affinity of this phage with NDV by an equilibrium binding assay in solution revealed two different dissociation constants, suggesting that there could be two distinct binding sites for the phage on NDV. Synthetic peptides with the sequence CTLTTKLYC, either in linear or cyclic conformations inhibited the binding of phage bearing the same sequence to NDV. These peptides also inhibited the hemolytic activity of the virus as well as its propagation in embryonated chicken eggs.
Cloning, expression and display of the PreS domain of hepatitis B virus on filamentous bacteriophage M13

Kok WL, Yusoff K, Nathan S, Tan WS

J. Biochem. Mol. Biol. Biophys., 2002 Feb;6(1):55-8.
PMID: 12186783

The PreS domain of hepatitis B virus (HBV) is believed to be involved in virion assembly and attachment to a hepatocyte receptor during infection. In order to study the functions of this region, we fused it to the g3p protein of bacteriophage M13 that allows the fusion protein to be displayed at the tip of the filament. The fusion protein was detected by the anti-E tag antibody on a Western blot. The polypeptide in a soluble form was produced by transfecting a non-suppressor E. coli host cell with the recombinant phagemid. The soluble protein was detected in cytoplasm, in the periplasmic space and also in the medium. The functional display of the PreS domain would provide an alternative means to study its interactions with the nuleocapsid and hepatocytes.
Cloning and expression of the phosphoprotein gene of Newcastle disease virus in Escherichia coli

Kho CL, Tan WS, Yusoff K

J. Biochem. Mol. Biol. Biophys., 2002 Apr;6(2):117-21.
PMID: 12186767

The phosphoprotein (P) gene of a heat stable Newcastle disease virus (NDV) was cloned, sequenced and expressed in Escherichia coli. SDS-PAGE analysis of the recombinant P protein (395 amino acids) and a C-terminal extension derivative (424 amino acids), gave rise to two distinct protein bands with molecular masses of approximately 53-55 and 56-58 kDa, respectively, which are approximately 26-30% heavier than those calculated from the deduced amino acid sequences. The differences in molecular mass on SDS-PAGE are thought to be attributed to the acidic nature of the P protein (pI=6.27) and also the different degrees of phosphorylation in the prokaryotic cell. Amino acid sequence comparison of the P protein among the published NDV strains showed that they were highly conserved particularly at the putative phosphorylation sites.
PCR cycle sequencing protocol for population mitochondrial cytochrome b analysis

Lau CH, Yusoff K, Tan SG, Yamada Y

Biotechniques, 1995 Feb;18(2):262-6.
PMID: 7727128

Laboratories intending to adopt cycle sequencing of PCR products in their routine analysis often face a confusing range of methods and kits. Through the study of mitochondrial cytochrome b, we have shown that clean and highly reproducible sequences could be obtained by using a combination of existing simple and economical methods in the preparation of DNA templates, PCR, purification of PCR products and sequencing. Our protocol is useful in itself or as a standard in typing other PCR-amplified DNA at the population level.
Fulltext Painful thyroiditis in postpartum period

Sakinah SO, Sharifah NA, Yusoff K

Med J Malaysia, 1993 Mar;48(1):83-5.
PMID: 8341177

Destructive thyroiditis commonly occurs during the postpartum period, with a prevalence rate of 5% to 16%, and is mainly due to postpartum autoimmune thyroiditis (PPT) and, very rarely, to subacute thyroiditis. The thyroiditis is similar to Hashimoto's thyroiditis and is generally painless in nature, although cases with painful thyroiditis have been described. We report a case of painful destructive thyroiditis occurring during the postpartum period, which was clinically and biochemically indistinguishable from the variant of painful PPT or subacute thyroiditis. Fine needle aspiration cytology showed multi-nucleated giant cells diagnostic of subacute thyroiditis.
Population structure of the Southeast Asian river catfish Mystus nemurus

Usmani S, Tan SG, Siraj SS, Yusoff K

Anim. Genet., 2003 Dec;34(6):462-4.
PMID: 14687079

A total of 143 microsatellites were isolated from Mystus nemurus using a 5' anchored polymerase chain reaction technique or the random amplified hybridization microsatellite method, the first set of microsatellite markers developed for the Southeast Asian river catfish. Twenty polymorphic microsatellite loci were used as markers for population characterization of M. nemurus from six different geographical locations in Malaysia (Perak, Kedah, Johor, UPM, Sarawak and Terengganu). The number of alleles per locus ranged from 2 to 11 with 6.3 as the average number of alleles per locus. Characterization of the populations showed relatively high levels of genetic variation compared with previous studies using allozyme markers. The highest genetic similarity was found between Perak and Kedah, while the highest genetic distance was found between Terengganu and Kedah. The majority of clustering was in accordance with geographical locations and the histories of the populations. Microsatellite analysis indicated that the Sarawak population might be genetically closer to the Peninsular Malaysian populations than has been previously shown by other molecular marker studies.
Fulltext Natural selection and local adaptation of blood pressure regulation and their perspectives on precision medicine in hypertension

Hoh BP, Abdul Rahman T, Yusoff K

Hereditas, 2019;156:1.
PMID: 30636949 DOI: 10.1186/s41065-019-0080-1

Prevalence of hypertension (HTN) varies substantially across different populations. HTN is not only common - affecting at least one third of the world's adult population - but is also the most important driver for cardiovascular diseases. Yet up to a third of hypertensive patients are resistant to therapy, contributed by secondary hypertension but more commonly the hitherto inability to precisely predict response to specific antihypertensive agents. Population and individual genomics information could be useful in guiding the selection and predicting the response to treatment - an approach known as precision medicine. However this cannot be achieved without the knowledge of genetic variations that influence blood pressure (BP). A number of evolutionary factors including population demographics and forces of natural selection may be involved. This article explores some ideas on how natural selection influences BP regulation in ethnically and geographically diverse populations that could lead to them being susceptible to HTN. We explore how such evolutionary factors could impact the implementation of precision medicine in HTN. Finally, in order to ensure the success of precision medicine in HTN, we call for more initiatives to understand the genetic architecture within and between diverse populations with ancestry from different parts of the world, and to precisely classify the intermediate phenotypes of HTN.
Nipah virus glycoprotein: production in baculovirus and application in diagnosis

Eshaghi M, Tan WS, Mohidin TB, Yusoff K

Virus Res, 2004 Nov;106(1):71-6.
PMID: 15522449

A method for serological diagnosis of Nipah virus (NiV) is described. DNA encoding truncated G protein of NiV was cloned into the pFastBac HT vector, and the fusion protein to His-tag was expressed in insect cells by recombinant baculovirus. The resulting His-G recombinant fusion protein was purified by affinity chromatography and used as the coating antigen for serological testing by indirect enzyme-linked immunosorbant assay (ELISA). When tested against a panel of swine serum samples, the recombinant G protein-based ELISA successfully discriminated all 40 samples previously determined to be serum neutralizing test (SNT) positive from 11 SNT negatives samples. The data show that the recombinant G protein exhibits the antigenic epitopes and conformation necessary for specific antigen-antibody recognition. The main advantage of the recombinant G protein-based NiV ELISA compared to an ELISA using whole virus antigen is the use of a single antigenic protein instead of inactivated whole virus which is required to be prepared under high risk and cost. This test is suitable for routine diagnosis of NiV and also for epidemiological surveys as it allows highly reliable testing of a large number of sera rapidly.
Detection and precipitation of hepatitis B core antigen using a fusion bacteriophage

Hasmoni SS, Yusoff K, Tan WS

J Gen Appl Microbiol, 2005 Apr;51(2):125-31.
PMID: 15942873

The nucleocapsids of hepatitis B virus (HBV) are made of 180 or 240 subunits of core proteins or known as core antigens (HBcAg). A fusion bacteriophage bearing the WSFFSNI sequence that interacts tightly to HBcAg was employed as a diagnostic reagent for the detection of the antigen using the phage-enzyme-linked immunosorbent (phage-ELISA), dot blot and immunoprecipitation assays. The results from phage-ELISA and dot blot assay showed that as low as 10 ng of HBcAg can be detected optimally by 1.0x10(12) pfu/ml fusion M13 bacteriophage. The sensitivity of the dot blot assay corresponds with that of the phage-ELISA. HBcAg in HBV positive serum samples can also be detected using the fusion phage via the phage-ELISA and phage-dot blot assay. The phage cross-linked to cyanogen bromide (CNBr) activated agarose can also be used to precipitate HBcAg in bacterial lysate. The optimum amount of phage needed for cross-linking to 1 g of agarose is about 7.0x10(6) pfu/ml which could also precipitate purified and unpurified HBcAg in bacterial lysate. This study demonstrates the potential of fusion bacteriophage bearing the sequence WSFFSNI as a diagnostic reagent and a ligand for the detection and purification of HBcAg respectively.
Improved protection from velogenic Newcastle disease virus challenge following multiple immunizations with plasmid DNA encoding for F and HN genes

Loke CF, Omar AR, Raha AR, Yusoff K

Vet Immunol Immunopathol, 2005 Jul 15;106(3-4):259-67.
PMID: 15963824

Specific-pathogen free (SPF) chickens were inoculated with the plasmid constructs encoding the fusion (F) and haemagglutinin-neuraminidase (HN) glycoproteins of Newcastle disease virus (NDV), either individually or in combination and challenged with velogenic NDV. The antibody level against NDV was measured using commercial enzyme linked immunosorbent assay (ELISA). In the first immunization regimen, SPF chickens inoculated twice with NDV-F or NDV-HN constructs elicited antibody responses 1 week after the second injection. However, the levels of the antibody were low and did not confer significant protection from the lethal challenge. In addition, administration of the plasmid constructs with Freund's adjuvant did not improve the level of protection. In the second immunization regimen, chickens inoculated twice with the plasmid constructs emulsified with Freund's adjuvant induced significant antibody titers after the third injection. Three out of nine (33.3%) chickens vaccinated with pEGFP-HN, five of ten (50.0%) chickens vaccinated with pEGFP-F and nine of ten (90.0%) chickens vaccinated with combined pEGFP-F and pEGFP-HN were protected from the challenge. No significant differences in the levels of protection were observed when the chickens were vaccinated with linearized pEGFP-F. The results suggested that more than two injections with both F and HN encoding plasmid DNA were required to induce higher level of antibodies for protection against velogenic NDV in chickens.
Display of hepatitis B virus PreS1 peptide on bacteriophage T7 and its potential in gene delivery into HepG2 cells

Tang KH, Yusoff K, Tan WS

J Virol Methods, 2009 Aug;159(2):194-9.
PMID: 19490973 DOI: 10.1016/j.jviromet.2009.03.015

Hepatitis B is a major public health problem worldwide which may lead to chronic liver diseases, cirrhosis and hepatocellular carcinoma. An interaction between hepatitis B virus (HBV) envelope protein, particularly the PreS1 region, and a specific cell surface receptor is believed to be the initial step of HBV infection through attachment to hepatocytes. In order to develop a gene delivery system, bacteriophage T7 was modified genetically to display polypeptides of the PreS1 region. A recombinant T7 phage displaying amino acids 60-108 of the PreS1 region (PreS1(60-108)) was demonstrated to be most effective in transfecting HepG2 cells in a dose- and time-dependant manner. The phage genome was recovered from the cell lysate and confirmed by PCR whereas the infectious form of the internalized phage was measured by a plaque-forming assay. The internalized phage exhibited the appearance of green fluorescent dots when examined by immunofluorescence microscopy. Surface modification, particularly by displaying the PreS1(60-108) enhanced phage uptake, resulting in more efficient in vitro gene transfer. The ability of the recombinant phage to transfect HepG2 cells demonstrates the potential of the phage display system as a gene therapy for liver cancer.
Fulltext Viral persistence in colorectal cancer cells infected by Newcastle disease virus

Chia SL, Yusoff K, Shafee N

Virol J, 2014 May 16;11:91.
PMID: 24886301 DOI: 10.1186/1743-422X-11-91

BACKGROUND: Newcastle disease virus (NDV), a single-stranded RNA virus of the family Paramyxoviridae, is a candidate virotherapy agent in cancer treatment. Promising responses were observed in clinical studies. Despite its high potential, the possibility of the virus to develop a persistent form of infection in cancer cells has not been investigated. Occurrence of persistent infection by NDV in cancer cells may cause the cells to be less susceptible to the virus killing. This would give rise to a population of cancer cells that remains viable and resistant to treatment.
RESULTS: During infection experiment in a series of colorectal cancer cell lines, we adventitiously observed a development of persistent infection by NDV in SW480 cells, but not in other cell lines tested. This cell population, designated as SW480P, showed resistancy towards NDV killing in a re-infection experiment. The SW480P cells retained NDV genome and produced virus progeny with reduced plaque forming ability.
CONCLUSION: These observations showed that NDV could develop persistent infection in cancer cells and this factor needs to be taken into consideration when using NDV in clinical settings.
Identification of epitopes in the nucleocapsid protein of Nipah virus using a linear phage-displayed random peptide library

Eshaghi M, Tan WS, Yusoff K

J Med Virol, 2005 Jan;75(1):147-52.
PMID: 15543570

A random peptide library of heptamers displayed on the surface of M13 bacteriophage was used to identify specific epitopes of antibodies in pooled sera of swine naturally infected by Nipah virus. The selected heptapeptides were aligned with protein sequences of Nipah virus and several putative epitopes were identified within the nucleocapsid protein. A total of 41 of 60 (68%) selected phage clones had inserts resembling a region with the sequence SNRTQGE, located at the C-terminal end (amino acids 503-509) of the nucleocapsid protein. The binding of antibodies in the swine and human antisera to the phage clone was inhibited by a synthetic peptide corresponding to this region. Epitopes identified by phage display are consistent with the predicted antigenic sites for the Nipah virus nucleocapsid protein. The selected phage clone used as a coating antigen discriminated swine and human Nipah virus sera-positive from sera-negative samples exhibiting characteristics, which might be attractive for diagnostic tests.
Does gamma irradiation affect physicochemical properties of honey?

Hussein SZ, Yusoff KM, Makpol S, Mohd Yusof YA

Clin Ter, 2014;165(2):e125-33.
PMID: 24770820 DOI: 10.7471/CT.2014.1695

Honey is a supersaturated solution of sugars, enriched with proteins, minerals, vitamins, organic acids and polyphenols. Gamma irradiation is a physical technique of food preservation which protects the honey from insects' and microbial contamination during storage. We investigated the effect of gamma irradiation on physicochemical properties in two types of Malaysian honey, Gelam and Nenas.
Fulltext Gelam honey attenuates carrageenan-induced rat paw inflammation via NF-κB pathway

Hussein SZ, Mohd Yusoff K, Makpol S, Mohd Yusof YA

PLoS One, 2013;8(8):e72365.
PMID: 24015236 DOI: 10.1371/journal.pone.0072365

The activation of nuclear factor kappa B (NF-κB) plays a major role in the pathogenesis of a number of inflammatory diseases. In this study, we investigated the anti-inflammatory mechanism of Gelam honey in inflammation induced rats via NF-κB signalling pathway. Rats paw edema was induced by subplantar injection of 1% carrageenan into the right hind paw. Rats were pre-treated with Gelam honey at different doses (1 or 2 g/kg, p.o.) and NSAID Indomethacin (10 mg/kg, p.o.), in two time points (1 and 7 days). Our results showed that Gelam honey at both concentrations suppressed the gene expressions of NF-κB (p65 & p50) and IκBα in inflamed rats paw tissues. In addition, Gelam honey inhibited the nuclear translocation and activation of NF-κB and decreased the cytosolic degradation of IκBα dose dependently in inflamed rats paw tissues. The immunohistochemical expressions of pro-inflammatory mediators COX-2 and TNF-α were also decreased in inflamed rats paw tissues when treated with Gelam honey. The results of our findings suggest that Gelam honey exhibits its inhibitory effects by attenuating NF-κB translocation to the nucleus and inhibiting IκBα degradation, with subsequent decrease of inflammatory mediators COX-2 and TNF-α.
Fulltext Antibacterial activity of selected Malaysian honey

Zainol MI, Mohd Yusoff K, Mohd Yusof MY

BMC Complement Altern Med, 2013;13:129.
PMID: 23758747 DOI: 10.1186/1472-6882-13-129

Antibacterial activity of honey is mainly dependent on a combination of its peroxide activity and non-peroxide components. This study aims to investigate antibacterial activity of five varieties of Malaysian honey (three monofloral; acacia, gelam and pineapple, and two polyfloral; kelulut and tualang) against Staphylococcus aureus, Bacillus cereus, Escherichia coli, and Pseudomonas aeruginosa.
Hypoxia affects cellular responses to plant extracts

Liew SY, Stanbridge EJ, Yusoff K, Shafee N

J Ethnopharmacol, 2012 Nov 21;144(2):453-6.
PMID: 23022321 DOI: 10.1016/j.jep.2012.09.024

Microenvironmental conditions contribute towards varying cellular responses to plant extract treatments. Hypoxic cancer cells are known to be resistant to radio- and chemo-therapy. New therapeutic strategies specifically targeting these cells are needed. Plant extracts used in Traditional Chinese Medicine (TCM) can offer promising candidates. Despite their widespread usage, information on their effects in hypoxic conditions is still lacking. In this study, we examined the cytotoxicity of a series of known TCM plant extracts under normoxic versus hypoxic conditions.
Development of a DNA vaccine against chicken anemia virus by using a bicistronic vector expressing VP1 and VP2 proteins of CAV

Moeini H, Omar AR, Rahim RA, Yusoff K

Comp Immunol Microbiol Infect Dis, 2011 May;34(3):227-36.
PMID: 21146874 DOI: 10.1016/j.cimid.2010.11.006

In the present study, we describe the development of a DNA vaccine against chicken anemia virus. The VP1 and VP2 genes of CAV were amplified and cloned into pBudCE4.1 to construct two DNA vaccines, namely, pBudVP1 and pBudVP2-VP1. In vitro and in vivo studies showed that co-expression of VP1 with VP2 are required to induce significant levels of antibody against CAV. Subsequently, the vaccines were tested in 2-week-old SPF chickens. Chickens immunized with the DNA-plasmid pBudVP2-VP1 showed positive neutralizing antibody titer against CAV. Furthermore, VP1-specific proliferation induction of splenocytes and also high serum levels of Th1 cytokines, IL-2 and IFN-γ were detected in the pBudVP2-VP1-vaccinated chickens. These results suggest that the recombinant DNA plasmid co-expressing VP1 and VP2 can be used as a potential DNA vaccine against CAV.

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