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Fulltext Distinct genetic lineages of Bactrocera caudata (Insecta: Tephritidae) revealed by COI and 16S DNA sequences

Lim PE, Tan J, Suana IW, Eamsobhana P, Yong HS

PLoS One, 2012;7(5):e37276.
PMID: 22615962 DOI: 10.1371/journal.pone.0037276

The fruit fly Bactrocera caudata is a pest species of economic importance in Asia. Its larvae feed on the flowers of Cucurbitaceae such as Cucurbita moschata. To-date it is distinguished from related species based on morphological characters. Specimens of B. caudata from Peninsular Malaysia and Indonesia (Bali and Lombok) were analysed using the partial DNA sequences of cytochrome c oxidase subunit I (COI) and 16S rRNA genes. Both gene sequences revealed that B. caudata from Peninsular Malaysia was distinctly different from B. caudata of Bali and Lombok, without common haplotype between them. Phylogenetic analysis revealed two distinct clades, indicating distinct genetic lineage. The uncorrected 'p' distance for COI sequences between B. caudata of Malaysia-Thailand-China and B. caudata of Bali-Lombok was 5.65%, for 16S sequences from 2.76 to 2.99%, and for combined COI and 16S sequences 4.45 to 4.46%. The 'p' values are distinctly different from intraspecific 'p' distance (0-0.23%). Both the B. caudata lineages are distinctly separated from related species in the subgenus Zeugodacus - B. ascita, B. scutellata, B. ishigakiensis, B. diaphora, B. tau, B. cucurbitae, and B. depressa. Molecular phylogenetic analysis indicates that the B. caudata lineages are closely related to B. ascita sp. B, and form a clade with B. scutellata, B. ishigakiensis, B. diaphora and B. ascita sp. A. This study provides additional baseline for the phylogenetic relationships of Bactrocera fruit flies of the subgenus Zeugodacus. Both the COI and 16S genes could be useful markers for the molecular differentiation and phylogenetic analysis of tephritid fruit flies.
Sun exposure and the risk of prostate cancer in the Singapore Prostate Cancer Study: a case-control study

Chia SE, Wong KY, Cheng C, Lau W, Tan PH

Asian Pac J Cancer Prev, 2012;13(7):3179-85.
PMID: 22994730

BACKGROUND: Most of the epidemiology studies on the effects of sun exposure and prostate cancer were conducted among the temperate countries of North America and Europe. Little is known about the influence on Asian populations. The purpose of current study was to evaluate any association of sun exposure with risk of prostate cancer in Chinese, Malays and Indians who reside in the tropics.
METHODS: The Singapore Prostate Cancer Study is a hospital-based case-control study of 240 prostate cancer incident cases and 268 controls conducted in Singapore between April 2007 and May 2009. Detailed information on outdoor activities in the sun, skin colour, sun sensitivity and other possible risk factors were collected in personal interviews. Cases were further classified by Gleason scores and TNM staging. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using unconditional logistic regression analysis, adjusted for age, ethnicity, education, family history of any cancers, BMI and skin colour.
RESULTS: We found that prostate cancer risk was increased in subjects with black/dark-brown eyes (OR 5.88, 95%CI 3.17-10.9), darker skin colour e.g. tan/dark brown/black (OR 7.62, 95%CI 3.41-17.0), frequent sunburn in lifetime (OR 4.30, 95%CI 1.7-11.2) and increased general sun exposure in adulthood per week (OR 2.03, 95%CI 1.09-3.81). The increased risk was consistent for high grade tumours and advanced stage prostate cancers.
CONCLUSION: The findings from this study suggest that excessive sun exposure is a risk factor for prostate cancer in Asians.
Fulltext Human facial neural activities and gesture recognition for machine-interfacing applications

Hamedi M, Salleh ShH, Tan TS, Ismail K, Ali J, Dee-Uam C, et al.

Int J Nanomedicine, 2011;6:3461-72.
PMID: 22267930 DOI: 10.2147/IJN.S26619

The authors present a new method of recognizing different human facial gestures through their neural activities and muscle movements, which can be used in machine-interfacing applications. Human-machine interface (HMI) technology utilizes human neural activities as input controllers for the machine. Recently, much work has been done on the specific application of facial electromyography (EMG)-based HMI, which have used limited and fixed numbers of facial gestures. In this work, a multipurpose interface is suggested that can support 2-11 control commands that can be applied to various HMI systems. The significance of this work is finding the most accurate facial gestures for any application with a maximum of eleven control commands. Eleven facial gesture EMGs are recorded from ten volunteers. Detected EMGs are passed through a band-pass filter and root mean square features are extracted. Various combinations of gestures with a different number of gestures in each group are made from the existing facial gestures. Finally, all combinations are trained and classified by a Fuzzy c-means classifier. In conclusion, combinations with the highest recognition accuracy in each group are chosen. An average accuracy >90% of chosen combinations proved their ability to be used as command controllers.
Angustilobine and andranginine type indole alkaloids and an uleine-secovallesamine bisindole alkaloid from Alstonia angustiloba

Ku WF, Tan SJ, Low YY, Komiyama K, Kam TS

Phytochemistry, 2011 Dec;72(17):2212-8.
PMID: 21889176 DOI: 10.1016/j.phytochem.2011.08.001

A total of 20 alkaloids were isolated from the leaf and stem-bark extracts of Alstonia angustiloba, of which two are hitherto unknown. One is an alkaloid of the angustilobine type (angustilobine C), while the other is a bisindole alkaloid angustiphylline, derived from the union of uleine and secovallesamine moieties. The structures of these alkaloids were established using NMR and MS analysis. Angustilobine C showed moderate cytotoxicity towards KB cells.
Nain-e Havandi Andrographis paniculata present yesterday, absent today: a plenary review on underutilized herb of Iran's pharmaceutical plants

Valdiani A, Kadir MA, Tan SG, Talei D, Abdullah MP, Nikzad S

Mol Biol Rep, 2012 May;39(5):5409-24.
PMID: 22198549 DOI: 10.1007/s11033-011-1341-x

Nain-e Havandi (Andrographis paniculata Nees.) (AP) is an annual herbaceous plant belonging to the family Acanthacea. Only a few species of Andrographis genus out of 28 are medicinally concerned of which AP is the most important. Knowledge about the arrival of AP to Iran is extremely lacking but most probably it has been imported from India. However, evidence implies the familiarity of Iran's folkloric medicine with this plant, but it has been disappeared from contemporary medicine for unknown reasons. Presence of active ingredients from diterpenoids group such as andrographolide, neoandrographolide and 14-deoxy-11,12-didehydroandrographolide has given incredible unique medicinal properties to the plant. Traditionally, Nain-e Havandi has been used in the role of a non-farm plant as a remedy for skin problems, flu, respiratory disease, and snakebite in East and Southeast Asia for centuries. Recently, it has been utilized as a treatment for HIV, hepatitis, diabetes, cancer and kidney disorders. Intensive cultivation of the herb started only in the past decade in countries such as China, India, Thailand, Indonesia, West Indies, Mauritius and to some extent, in Malaysia. Availability of different ecological zones in Iran complies with reestablishment of AP in tropical and temperate regions of the country. This is killing two birds with one stone, supporting the conservational and economic aspects.
Fulltext Rehydrated sterically stabilized phospholipid nanomicelles of budesonide for nebulization: physicochemical characterization and in vitro, in vivo evaluations

Sahib MN, Darwis Y, Peh KK, Abdulameer SA, Tan YT

Int J Nanomedicine, 2011;6:2351-66.
PMID: 22072872 DOI: 10.2147/IJN.S25363

Inhaled corticosteroids provide unique systems for local treatment of asthma or chronic obstructive pulmonary disease. However, the use of poorly soluble drugs for nebulization has been inadequate, and many patients rely on large doses to achieve optimal control of their disease. Theoretically, nanotechnology with a sustained-release formulation may provide a favorable therapeutic index. The aim of this study was to determine the feasibility of using sterically stabilized phospholipid nanomicelles of budesonide for pulmonary delivery via nebulization.
Validity and reliability of the Malay-language translation of the Rome III Diagnostic Questionnaire for irritable bowel syndrome

Lee YY, Waid A, Tan HJ, Chua SB, Whitehead WE

J Gastroenterol Hepatol, 2012 Apr;27(4):746-50.
PMID: 22004172 DOI: 10.1111/j.1440-1746.2011.06943.x

The Malay language is widely used within the "Malay Archipelago" particularly in Malaysia, Indonesia, Philippines, Singapore and Brunei with a combined population of 300 million. There are no reliable data on the epidemiology of irritable bowel syndrome (IBS) in the Malay speaking population because the Rome Diagnostic Questionnaire has not been translated and validated for the Malay language. The current study aimed to translate and validate the Rome III IBS Diagnostic Questionnaire, Red Flag and Psychosocial Alarm questionnaires into the Malay language.
Impact of interventional nephrology on outcome and penetration rate of a CAPD program

Wong CM, Ng KP, Keng TC, Lim SK, Tan SY

Perit Dial Int, 2011 3 24;31(2):194-6.
PMID: 21427247 DOI: 10.3747/pdi.2009.00237
Characterization of Malaysian Trichoderma isolates using random amplified microsatellites (RAMS)

Siddiquee S, Tan SG, Yusuf UK, Fatihah NH, Hasan MM

Mol Biol Rep, 2012 Jan;39(1):715-22.
PMID: 21553047 DOI: 10.1007/s11033-011-0790-6

Trichoderma species are commercially applied as biocontrol agents against numerous plant pathogenic fungi due to their production of antifungal metabolites, competition for nutrients and space, and mycoparasitism. However, currently the identification of Trichoderma species from throughout the world based on micro-morphological descriptions is tedious and prone to error. The correct identification of Trichoderma species is important as several traits are species-specific. The Random Amplified Microsatellites (RAMS) analysis done using five primers in this study showed different degrees of the genetic similarity among 42 isolates of this genus. The genetic similarity values were found to be in the range of 12.50-85.11% based on a total of 76 bands scored in the Trichoderma isolates. Of these 76 bands, 96.05% were polymorphic, 3.95% were monomorphic and 16% were exclusive bands. Two bands (250 bp and 200 bp) produced by primer LR-5 and one band (250 bp) by primer P1A were present in all the Trichoderma isolates collected from healthy and infected oil palm plantation soils. Cluster analysis based on UPGMA of the RAMS marker data showed that T. harzianum, T. virens and T. longibrachiatum isolates were grouped into different clades and lineages. In this study we found that although T. aureoviride isolates were morphologically different when compared to T. harzianum isolates, the UPGMA cluster analysis showed that the majority isolates of T. aureoviride (seven from nine) were closely related to the isolates of T. harzianum.
Fulltext Food assimilated by two sympatric populations of the brown planthopper Nilaparvata lugens (Delphacidae) feeding on different host plants contaminates insect DNA detected by RAPD-PCR analysis

Latif MA, Omar MY, Tan SG, Siraj SS, Ali ME, Rafii MY

Genet. Mol. Res., 2012;11(1):30-41.
PMID: 22290463 DOI: 10.4238/2012.January.9.4

Contamination of insect DNA for RAPD-PCR analysis can be a problem because many primers are non-specific and DNA from parasites or gut contents may be simultaneously extracted along with that of the insect. We measured the quantity of food ingested and assimilated by two sympatric populations of brown planthopper (BPH), Nilaparvata lugens, one from rice and the other from Leersia hexandra (Poaceae), a wetland forage grass, and we also investigated whether host plant DNA contaminates that of herbivore insects in extractions of whole insects. Ingestion and assimilation of food were reduced significantly when individuals derived from one host plant were caged on the other species. The bands, OPA3 (1.25), OPD3 (1.10), OPD3 (0.80), OPD3 (0.60), pUC/M13F (0.35), pUC/M13F (0.20), BOXAIR (0.50), peh#3 (0.50), and peh#3 (0.17) were found in both rice-infesting populations of brown planthopper and its host plant (rice). Similarly, the bands, OPA4 (1.00), OPB10 (0.70), OPD3 (0.90), OPD3 (0.80), OPD3 (0.60), pUC/ M13F (0.35), pUC/M13F (0.20), and BOXAIR (0.50) were found in both Leersia-infesting populations of brown planthopper and the host plant. So, it is clear that the DNA bands amplified in the host plants were also found in the extracts from the insects feeding on them.
Thickened carotid intima media thickness and carotid atherosclerosis among lupus nephritis patients: the role of traditional and lupus-specific factors

Sazliyana S, Mohd Shahrir MS, Kong NC, Tan HJ, Hamidon BB, Azmi MT

Int J Rheum Dis, 2011 Aug;14(3):267-75.
PMID: 21816023 DOI: 10.1111/j.1756-185X.2011.01638.x

AIM: The objectives of this study were to investigate the frequency of thickened carotid intima media thickness (CIMT) and atherosclerosis among lupus nephritis (LN) patients and to study their associated risk factors.
METHOD: In this cross-sectional study, carotid ultrasonography was performed on consecutive LN patients to determine CIMT and presence of carotid plaques. CIMT was considered to be abnormally thickened if it was more than the 75th percentile matched for age and sex from the 'Carotid Atherosclerosis Progression Study'. The association between thickened CIMT with traditional cardiovascular risk factors and lupus characteristics were examined. A total of 83 patients with the mean age of 33.6 ± 10 years were recruited.
RESULTS: Fourteen patients (16.9%) had thickened CIMT and three (3.6%) had carotid plaques. On univariate analysis, traditional risk factors significantly associated with thickened CIMT (P < 0.05) were patient's current age, diabetes mellitus and waist circumference. Meanwhile, a lower serum C4 levels and higher serum C-reactive protein levels were the lupus-specific factors associated with thickened CIMT (P < 0.05, P < 0.05 and P < 0.01, respectively). In logistic regression analysis, the independent predictors of thickened CIMT were age of diagnosis, lower serum C4 levels and waist circumference (P < 0.05).
CONCLUSION: More lupus specific factors were independently associated with thickened CIMT, suggesting that a multi-targeted approach of treatment addressing both the lupus and traditional cardiovascular risks are very important. Larger prospective studies of these special risk factors are indicated.
Fulltext Evidence for a higher number of species of Odontotermes (Isoptera) than currently known from Peninsular Malaysia from mitochondrial DNA phylogenies

Cheng S, Kirton LG, Panandam JM, Siraj SS, Ng KK, Tan SG

PLoS One, 2011;6(6):e20992.
PMID: 21687629 DOI: 10.1371/journal.pone.0020992

Termites of the genus Odontotermes are important decomposers in the Old World tropics and are sometimes important pests of crops, timber and trees. The species within the genus often have overlapping size ranges and are difficult to differentiate based on morphology. As a result, the taxonomy of Odontotermes in Peninsular Malaysia has not been adequately worked out. In this study, we examined the phylogeny of 40 samples of Odontotermes from Peninsular Malaysia using two mitochondrial DNA regions, that is, the 16S ribosomal RNA and cytochrome oxidase subunit I genes, to aid in elucidating the number of species in the peninsula. Phylogenies were reconstructed from the individual gene and combined gene data sets using parsimony and likelihood criteria. The phylogenies supported the presence of up to eleven species in Peninsular Malaysia, which were identified as O. escherichi, O. hainanensis, O. javanicus, O. longignathus, O. malaccensis, O. oblongatus, O. paraoblongatus, O. sarawakensis, and three possibly new species. Additionally, some of our taxa are thought to comprise a complex of two or more species. The number of species found in this study using DNA methods was more than the initial nine species thought to occur in Peninsular Malaysia. The support values for the clades and morphology of the soldiers provided further evidence for the existence of eleven or more species. Higher resolution genetic markers such as microsatellites would be required to confirm the presence of cryptic species in some taxa.
Fulltext Cyclic Tetrapyrrolic Photosensitisers from the leaves of Phaeanthus ophthalmicus

Tan PJ, Ong CY, Danial A, Yusof HM, Neoh BK, Lee HB

Chem Cent J, 2011;5:32.
PMID: 21682931 DOI: 10.1186/1752-153X-5-32

Twenty-seven extracts from 26 plants were identified as photo-cytotoxic in the course of our bioassay guided screening program for photosensitisers from 128 extracts prepared from 64 terrestrial plants in two different collection sites in Malaysia - Royal Belum Forest Reserve in the State of Perak and Gunung Nuang in the State of Selangor. One of the photo-cytotoxic extracts from the leaves of Phaeanthus ophtalmicus was further investigated.
Fulltext Head and neck cancer: possible causes for delay in diagnosis and treatment

Lee SC, Tang IP, Avatar SP, Ahmad N, Selva KS, Tay KK, et al.

Med J Malaysia, 2011 Jun;66(2):101-4.
PMID: 22106686 MyJurnal

To explore the possible causes for delay in diagnosis and treatment of head and neck cancer at Sarawak General Hospital (SGH).
Protein-binding affinity of leucaena condensed tannins of differing molecular weights

Huang XD, Liang JB, Tan HY, Yahya R, Long R, Ho YW

J Agric Food Chem, 2011 Oct 12;59(19):10677-82.
PMID: 21899359 DOI: 10.1021/jf201925g

Depending on their source, concentration, chemical structure, and molecular weight, condensed tannins (CTs) form insoluble complexes with protein, which could lead to ruminal bypass protein, benefiting animal production. In this study, CTs from Leuceana leucocephala hybrid were fractionated into five fractions by a size exclusion chromatography procedure. The molecular weights of the CT fractions were determined using Q-TOF LC-MS, and the protein-binding affinities of the respective CT fractions were determined using a protein precipitation assay with bovine serum albumin (BSA) as the standard protein. The calculated number-average molecular weights (M(n)) were 1348.6, 857.1, 730.1, 726.0, and 497.1, and b values (the b value represents the CT quantity that is needed to bind half of the maximum precipitable BSA) of the different molecular weight fractions were 0.381, 0.510, 0.580, 0.636, and 0.780 for fractions 1, 2, 3, 4, and 5, respectively. The results indicated that, in general, CTs of higher molecular weight fractions have stronger protein-binding affinity than those of lower molecular weights. However, the number of hydroxyl units within the structure of CT polymers also affects the protein-binding affinity.
Evaluation of the sub-acute toxicity of the sclerotium of Lignosus rhinocerus (Cooke), the Tiger Milk mushroom

Lee SS, Tan NH, Fung SY, Pailoor J, Sim SM

J Ethnopharmacol, 2011 Oct 31;138(1):192-200.
PMID: 21930194 DOI: 10.1016/j.jep.2011.09.004

Lignosus rhinocerus (known locally as 'Tiger Milk mushroom') is the most important medicinal mushroom used by the indigenous communities of Malaysia to treat fever, cough, asthma, cancer, food poisoning and as a general tonic. The sclerotium of the mushroom is the part with medicinal value. Lignosus rhinocerus was hitherto unexploited commercially because of limited supply. Recently, the mushroom was successfully cultivated.
Evaluation of carbon-based nanosorbents synthesised by ethylene decomposition on stainless steel substrates as potential sequestrating materials for nickel ions in aqueous solution

Lee XJ, Lee LY, Foo LP, Tan KW, Hassell DG

J Environ Sci (China), 2012;24(9):1559-68.
PMID: 23520862

The present work covers the preparation of carbon-based nanosorbents by ethylene decomposition on stainless steel mesh without the use of external catalyst for the treatment of water containing nickel ions (Ni2+). The reaction temperature was varied from 650 to 850 degrees C, while reaction time and ethylene to nitrogen flow ratio were maintained at 30 min and 1:1 cm3/min, respectively. Results show that nanosorbents synthesised at a reaction temperature of 650 degrees C had the smallest average diameter (75 nm), largest BET surface area (68.95 m2/g) and least amount of impurity (0.98 wt.% Fe). A series of batch-sorption tests were performed to evaluate the effects of initial pH, initial metal concentration and contact time on Ni2+ removal by the nanosorbents. The equilibrium data fitted well to Freundlich isotherm. The kinetic data were best correlated to a pseudo second-order model indicating that the process was of chemisorption type. Further analysis by the Boyd kinetic model revealed that boundary layer diffusion was the controlling step. This primary study suggests that the prepared material with Freundlich constants compared well with those in the literature, is a promising sorbent for the sequestration of Ni2+ in aqueous solutions.
Extractive fermentation for improved production and recovery of lipase derived from Burkholderia cepacia using a thermoseparating polymer in aqueous two-phase systems

Show PL, Tan CP, Shamsul Anuar M, Ariff A, Yusof YA, Chen SK, et al.

Bioresour Technol, 2012 Jul;116:226-33.
PMID: 22061444 DOI: 10.1016/j.biortech.2011.09.131

An extractive fermentation technique was developed using a thermoseparating reagent to form a two-phase system for simultaneous cell cultivation and downstream processing of extracellular Burkholderia cepacia lipase. A 10% (w/w) solution of ethylene oxide-propylene oxide (EOPO) with a molecular mass of 3900 g/mol and pH 8.5, a 200 rpm speed, and 30 °C were selected as the optimal conditions for lipase production (55 U/ml). Repetitive batch fermentation was performed by continuous replacement of the top phase every 24h, which resulted in an average cell growth mass of 4.7 g/L for 10 extractive batches over 240 h. In scaling-up the process, a bench-scale bioreactor was tested under the conditions that had been optimized in flasks. The production rate and recovery yield were higher in the bioreactor compared to fermentation performed in flasks.
Conformational destabilization of Bacillus licheniformis α-amylase induced by lysine modification and calcium depletion

Tan CY, Rahman RN, Kadir HA, Tayyab S

Acta Biochim. Pol., 2011;58(3):405-12.
PMID: 21887412

Bacillus licheniformis α-amylase (BLA) was chemically modified using 100-fold molar excess of succinic anhydride over protein or 0.66 M potassium cyanate to obtain 42 % succinylated and 81 % carbamylated BLAs. Size and charge homogeneity of modified preparations was established by Sephacryl S-200 HR gel chromatography and polyacrylamide gel electrophoresis. Conformational alteration in these preparations was evident by the larger Stokes radii (3.40 nm for carbamylated and 3.34 nm for succinylated BLAs) compared to 2.43 nm obtained for native BLA. Urea denaturation results using mean residue ellipticity (MRE) as a probe also showed conformational destabilization based on the early start of transition as well as ΔG(D)(H(2)O) values obtained for both modified derivatives and Ca-depleted BLA. Decrease in ΔG(D)(H(2)O) value from 5,930 cal/mol (for native BLA) to 3,957 cal/mol (for succinylated BLA), 3,336 cal/mol (for carbamylated BLA) and 3,430 cal/mol for Ca-depleted BLA suggested reduced conformational stability upon modification of amino groups of BLA or depletion of calcium. Since both succinylation and carbamylation reactions abolish the positive charge on amino groups (both α- and ε- amino), the decrease in conformational stability can be ascribed to the disruption of salt bridges present in the protein which might have released the intrinsic calcium from its binding site.
Optimisation of freeze drying conditions for purified serine protease from mango (Mangifera indicaCv. Chokanan) peel

Mehrnoush A, Tan CP, Hamed M, Aziz NA, Ling TC

Food Chem, 2011 Sep 1;128(1):158-64.
PMID: 25214343 DOI: 10.1016/j.foodchem.2011.03.012

This study investigated the possible relationship between the encapsulation variables, namely serine protease content (9-50mg/ml, X1), Arabic gum (0.2-10%(w/w), X2), maltodextrin (2-5%(w/w), X3) and calcium chloride (1.3-5.5%(w/w), X4) on the enzymatic properties of encapsulated serine protease. The study demonstrated that Arabic gum, maltodextrin and calcium chloride, as coating agents, protected serine protease from activity loss during freeze-drying. The overall optimum region resulted in a suitable freeze drying condition with a yield of 92% for the encapsulated serine protease, were obtained using 29.5mg/ml serine protease content, 5.1%(w/w) Arabic gum, 3.5%(w/w) maltodextrin and 3.4%(w/w) calcium chloride. It was found that the interaction effect of Arabic gum and calcium chloride improved the serine protease activity, and Arabic gum was the most effective amongst the examined coating agents. Thus, Arabic gum should be considered as potential protection in freeze drying of serine protease.

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