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A new species of Cerapus (Amphipoda: Senticaudata: Ischyroceridae) from Pulau Bum Bum, Sabah, Malaysia, with an identification key to Cerapus species

Nurshazwan J, Ahmad-Zaki AB, Azman BAR

Zootaxa, 2020 Jun 24;4802(3):zootaxa.4802.3.7.
PMID: 33056047 DOI: 10.11646/zootaxa.4802.3.7

The first representative of the genus Cerapus in Malaysian waters, Cerapus bumbumiensis sp. nov. is described from specimens sampled from Pulau Bum Bum, Sabah (east Malaysia). The main identifying characteristics of this new amphipod species are: pereonites 1, 2 with constriction; male gnathopod 2 carpochelate, carpus large with long defining posterior tooth and well-developed anterodistal tooth; pereopod 6 coxa with fine hair/fringe setae ventrally; and telson with deep cleft. An updated identification key for the 23 known species in the genus is also presented.
Difatty acyl urea from corn oil: synthesis and characterization

Al-Mulla EA, Yunus WM, Ibrahim NA, Rahman MZ

J Oleo Sci, 2010;59(3):157-60.
PMID: 20124758

In this study, difatty acyl urea has been successfully synthesized from corn oil using sodium ethoxide as a catalyst. Ethyl fatty ester and glycerol were produced as by-products. In this reaction, corn oil was refluxed with urea in ethanol. The highest conversion percentage (78%) was obtained when the process was carried out for 8 hours using urea to corn oil ratio of 5.6: 1.0 at 78 degrees C. Both difatty acyl urea and ethyl fatty ester have been characterized using elemental analysis, Fourier transform infrared (FTIR) spectroscopy and (1)H nuclear magnetic resonance (NMR) technique.
Synthesis and characterization of N,N'-carbonyl difatty amides from palm oil

Al-Mulla EA, Yunus WM, Ibrahim NA, Rahman MZ

J Oleo Sci, 2009;58(9):467-71.
PMID: 19654456

N,N'-Carbonyl difatty amides (CDFAs) have been synthesized from palm oil using sodium ethoxide as catalyst. Ethyl fatty esters (EFEs) were produced as a by-product as well as glycerol. The synthesis was carried out by reflux palm oil and urea in presence of ethanol. In this process, palm oil gave 79% pure CDFAs after 8 hours and molar ratio of urea to palm oil was 6.2: 1 at 78 degrees C. Both CDFAs and EFEs have been characterized using elemental analysis, Fourier transform infrared (FTIR) spectroscopy and (1)H nuclear magnetic resonance (NMR) technique.
Enzymatic synthesis of fatty amides from palm olein

Al-Mulla EA, Yunus WM, Ibrahim NA, Rahman MZ

J Oleo Sci, 2010;59(2):59-64.
PMID: 20103977

Fatty amides have been successfully synthesized from palm olein and urea by a one-step lipase catalyzed reaction. The use of immobilized lipase as the catalyst for the preparation reaction provides an easy isolation of the enzyme from the products and other components in the reaction mixture. The fatty amides were characterized using Fourier transform infrared (FTIR) spectroscopy, proton nuclear magnetic resonance ((1)H NMR) technique and elemental analysis. The highest conversion percentage (96%) was obtained when the process was carried out for 36 hours using urea to palm oil ratio of 5.2: 1.0 at 40 degrees C. The method employed offers several advantages such as renewable and abundant of the raw material, simple reaction procedure, environmentally friendly process and high yield of the product.
Fulltext Non-Destructive Evaluation for Corrosion Monitoring in Concrete: A Review and Capability of Acoustic Emission Technique

Zaki A, Chai HK, Aggelis DG, Alver N

Sensors (Basel), 2015;15(8):19069-101.
PMID: 26251904 DOI: 10.3390/s150819069

Corrosion of reinforced concrete (RC) structures has been one of the major causes of structural failure. Early detection of the corrosion process could help limit the location and the extent of necessary repairs or replacement, as well as reduce the cost associated with rehabilitation work. Non-destructive testing (NDT) methods have been found to be useful for in-situ evaluation of steel corrosion in RC, where the effect of steel corrosion and the integrity of the concrete structure can be assessed effectively. A complementary study of NDT methods for the investigation of corrosion is presented here. In this paper, acoustic emission (AE) effectively detects the corrosion of concrete structures at an early stage. The capability of the AE technique to detect corrosion occurring in real-time makes it a strong candidate for serving as an efficient NDT method, giving it an advantage over other NDT methods.
Liquefaction of kenaf (Hibiscus cannabinus L.) core for wood laminating adhesive

Juhaida MF, Paridah MT, Mohd Hilmi M, Sarani Z, Jalaluddin H, Mohamad Zaki AR

Bioresour Technol, 2010 Feb;101(4):1355-60.
PMID: 19833509 DOI: 10.1016/j.biortech.2009.09.048

A study was carried out to produce polyurethane (PU) as a wood laminating adhesive from liquefied kenaf core (LKC) polyols by reacting it with toluene-2,4-diisocyanate (TDI) and 1,4-butanediol (BDO). The LKC polyurethane (LKCPU) adhesive has a molecular weight (MW) of 2666, viscosity of 5370 mPa s, and solids content of 86.9%. The average shear strength of the rubberwood (RW) bonded with LKCPU adhesive was 2.9 MPa. Most of the sheared specimens experienced a total adhesive failure. The formation of air bubbles through the liberation of carbon dioxide was observed to reduce the adhesive penetration and bonding strength which was obviously seen on the sheared specimens. The percentage of catalyst used can be varied based on the usage and working time needed. Nonetheless, the physical properties of LKCPU produced in this work had shown good potential as edge-bonding adhesive.
Mitochondrial Cytochrome Oxidase I Gene Sequence Analysis of Aedes Albopictus in Malaysia

Ismail NA, Dom NC, Ismail R, Ahmad AH, Zaki A, Camalxaman SN

J Am Mosq Control Assoc, 2015 Dec;31(4):305-12.
PMID: 26675451 DOI: 10.2987/moco-31-04-305-312.1

A study was conducted to establish polymorphic variation of the mitochondrial DNA encoding the cytochrome oxidase subunit 1 (CO1) gene in Aedes albopictus isolated from 2 hot spot dengue-infested areas in the Subang Jaya District, Malaysia. A phylogenetic analysis was performed with the use of sequences obtained from USJ6 and Taman Subang Mas (TSM). Comparison of the local CO1 sequences with a laboratory strain (USM), alongside reference strains derived from the GenBank database revealed low genetic variation in terms of nucleotide differences and haplotype diversity. Four methods were used to construct a phylogenetic tree and illustrate the genetic relationship of the 37 Ae. albopictus populations based on the CO1 sequences, namely neighbor-joining (NJ), maximum parsimony (MP), maximum likelihood (ML), and Bayesian method, which revealed a distinct relationship between isolates from USJ6 and TSM. Our findings provide new information regarding the genetic diversity among morphologically similar Ae. albopictus, which has not been reported to date.
Fulltext Diagnostic Accuracy of FOBT and Colorectal Cancer Genetic Testing: A Systematic Review & Meta-Analysis

Ramdzan AR, Abd Rahim MA, Mohamad Zaki A, Zaidun Z, Mohammed Nawi A

Ann Glob Health, 2019 05 15;85(1).
PMID: 31099505 DOI: 10.5334/aogh.2466

INTRODUCTION: Colorectal cancer (CRC) is the second leading cause of cancer related death in the world after lung cancer. Early detection of CRC leads to improvement in cancer survival rate. In recent years, efforts have been made to discover a non-invasive screening marker of higher sensitivity and specificity. Fecal occult blood testing (FOBT) and genetic testing become alternative modalities to screen CRC in the population other than colonoscopy. The aim of this systematic review and meta-analysis is to determine the diagnostic accuracy, sensitivity and specificity of FOBT and genetic testing as screening tools in colorectal cancer.
METHODS: A literature search of PubMed, ScienceDirect, and Scopus was carried out. The search strategy was restricted to human subjects and studies are published in English. Data on sensitivity and specificity were extracted and pooled. Heterogeneity was assumed at significance level of p < 0.10 and was tested by chi squared. Degree of heterogeneity was quantified using the I2 statistic, and values of less than 25% is considered as homogenous. All analyses were performed using the software Meta-Disc.
RESULTS: A total of eleven studies were suitable for data synthesis and analysis. Five studies were analyzed for the accuracy of genetic testing, the pooled estimate for sensitivity and specificity were 71% (95% CI: 66, 75%) and 95% (95% CI: 93, 97%) respectively. Another group of studies which had been evaluated for the accuracy of FOBT, the pooled sensitivity was 31% (95% CI: 25, 38%) while the pooled specificity was 87% (95% CI: 86, 89%).
CONCLUSIONS: FOBTs is recommended to use as population-based screening tools for colorectal cancer while genetic testing should be focusing on patients with moderate and high risk individuals.
Radiation and temperature effects on conductivity properties of PVA-KOH-PC composite

Mohd Asri MT, Elias S, Iskandar SM, Abd Halim S, Jumiah H, Zaki AR, et al.

Med J Malaysia, 2004 May;59 Suppl B:139-40.
PMID: 15468857

The aim of this work was to study radiation and the effects of temperature on conductivity properties of polyvinyl alcohol (PVA)-based potassium hydroxide (KOH) and propylene carbonate (PC), where the ionic conduction preferentially occurs in the amorphous phase by free radicals ions through gamma-irradiation. Alkaline composite polymer electrolyte (ACPE) consisting of PVA, KOH and PC of different concentration ratios were prepared by solvent-casting technique. The ACPE were irradiated with different doses from 5 kGy up to 200 kGy. The conductivity properties of the electrolyte films were measured at different frequencies in the range 20 Hz to 1 MHz using LCR meter. The results showed that the conductivity properties were dependent on the radiation dose, temperature and the concentration of the polymer blends.
Fulltext Testing the impact of virus importation rates and future climate change on dengue activity in Malaysia using a mechanistic entomology and disease model

Williams CR, Gill BS, Mincham G, Mohd Zaki AH, Abdullah N, Mahiyuddin WR, et al.

Epidemiol Infect, 2015 Oct;143(13):2856-64.
PMID: 25591942 DOI: 10.1017/S095026881400380X

We aimed to reparameterize and validate an existing dengue model, comprising an entomological component (CIMSiM) and a disease component (DENSiM) for application in Malaysia. With the model we aimed to measure the effect of importation rate on dengue incidence, and to determine the potential impact of moderate climate change (a 1 °C temperature increase) on dengue activity. Dengue models (comprising CIMSiM and DENSiM) were reparameterized for a simulated Malaysian village of 10 000 people, and validated against monthly dengue case data from the district of Petaling Jaya in the state of Selangor. Simulations were also performed for 2008-2012 for variable virus importation rates (ranging from 1 to 25 per week) and dengue incidence determined. Dengue incidence in the period 2010-2012 was modelled, twice, with observed daily weather and with a 1 °C increase, the latter to simulate moderate climate change. Strong concordance between simulated and observed monthly dengue cases was observed (up to r = 0·72). There was a linear relationship between importation and incidence. However, a doubling of dengue importation did not equate to a doubling of dengue activity. The largest individual dengue outbreak was observed with the lowest dengue importation rate. Moderate climate change resulted in an overall decrease in dengue activity over a 3-year period, linked to high human seroprevalence early on in the simulation. Our results suggest that moderate reductions in importation with control programmes may not reduce the frequency of large outbreaks. Moderate increases in temperature do not necessarily lead to greater dengue incidence.
Fulltext Anti-tumor activity of Eurycoma longifolia root extracts against K-562 cell line: in vitro and in vivo study

Al-Salahi OS, Ji D, Majid AM, Kit-Lam C, Abdullah WZ, Zaki A, et al.

PLoS One, 2014;9(1):e83818.
PMID: 24409284 DOI: 10.1371/journal.pone.0083818

Eurycoma longifolia Jack has been widely used in traditional medicine for its antimalarial, aphrodisiac, anti-diabetic, antimicrobial and anti-pyretic activities. Its anticancer activity has also been recently reported on different solid tumors, however no anti-leukemic activity of this plant has been reported. Thus the present study assesses the in vitro and in vivo anti-proliferative and apoptotic potentials of E. longifolia on K-562 leukemic cell line. The K-562 cells (purchased from ATCC) were isolated from patients with chronic myelocytic leukemia (CML) were treated with the various fractions (TAF273, F3 and F4) of E. longifolia root methanolic extract at various concentrations and time intervals and the anti-proliferative activity assessed by MTS assay. Flow cytometry was used to assess the apoptosis and cell cycle arrest. Nude mice injected subcutaneously with 10(7) K-562 cells were used to study the anti-leukemic activity of TAF273 in vivo. TAF273, F3 and F4 showed various degrees of growth inhibition with IC50 values of 19, 55 and 62 µg/ml, respectively. TAF273 induced apoptosis in a dose and time dependent manner. TAF273 arrested cell cycle at G1 and S phases. Intraperitoneal administration of TAF273 (50 mg/kg) resulted in a significant growth inhibition of subcutaneous tumor in TAF273-treated mice compared with the control mice (P = 0.024). TAF273 shows potent anti-proliferative activity in vitro and in vivo models of CML and therefore, justifies further efforts to define more clearly the potential benefits of using TAF273 as a novel therapeutic strategy for CML management.
Molecular phylogeny of modern coxsackievirus A16

Perera D, Yusof MA, Podin Y, Ooi MH, Thao NT, Wong KK, et al.

Arch Virol, 2007;152(6):1201-8.
PMID: 17308978

A phylogenetic analysis of VP1 and VP4 nucleotide sequences of 52 recent CVA16 strains demonstrated two distinct CVA16 genogroups, A and B, with the prototype strain being the only member of genogroup A. CVA16 G-10, the prototype strain, showed a nucleotide difference of 27.7-30.2% and 19.9-25.2% in VP1 and VP4, respectively, in relation to other CVA16 strains, which formed two separate lineages in genogroup B with nucleotide variation of less than 13.4% and less than 16.3% in VP1 and VP4, respectively. Lineage 1 strains circulating before 2000 were later displaced by lineage 2 strains.