Dalam parasit intrasel obligat seperti Eimeria tenella, protein membran dipercayai memainkan peranan yang penting dalam pengecaman dan pelekatan pada sel perumah supaya proses penyerangan parasit ke dalam sel perumah dapat disempurnakan. Untuk mengenalpasti protein pada membran E. tenella, penyaringan imuno telah dilakukan dengan menggunakan antiserum terhadap fraksi subsel yang telah diperkayakan dengan protein membran sporozoit. Usaha penyaringan imuno ini berjaya memencilkan 21 klon positif. Daripada jumlah ini, 13 klon menunjukkan pemadanan bermakna dengan jujukan dalam pangkalan data, iaitu 11 dengan protein mikronem EtMIC4, satu dengan EtMIC1 dan satu lagi dengan EtMIC2. Lapan klon selebihnya yang tidak menunjukkan sebarang pemadanan bermakna dengan jujukan dalam pangkalan data didapati membawa lima gen yang berlainan. Secara keseluruhannya, hasil kajian ini menunjukkan bahawa kaedah penyaringan imuno berupaya mengenalpasti gen baru yang kemungkinan besar mengekodkan protein membran dalam sporozoit E. tenella.
The ability of a locally isolated clinical strain of C. albicans to adapt and response towards oxidative stress were investigated in this study. Treatment of C. albicans with hydrogen peroxide (H2O2) will exert an oxidative stress to C. albicans cells and affect the growth rate of this opportunistic pathogen. Cells that were grown in Yeast Peptone Dextrose (YPD) medium with the presence of 4.0 mM H2O2 gave a doubling time of 51 min/generation compared to 44 min/generation for those grown in 0.4 mM H2O2 and without H2O2. In order to determine the resistance level of C. albicans towards oxidative stress, cells were exposed to different concentration of H2O2. Results showed that percentage of cells viability decreased with the increased concentration of H2O2. These data indicated that C. albicans could overcome oxidative stress to a certain level before they were killed. To determine whether this strain exhibited a stress induce protection, cells were treated with mild oxidative stress for one hour before exposed to a stronger oxidative stress. Data obtained shows that cells that were pre-treated with mild oxidative stress showed higher percentage of survival compared to non pre-treated cells. This strongly suggested that stress induce protection was present in this C. albicans. Finally, in order to determine whether oxidative stress can induce yeast to hyphal morphogenesis in C. albicans, cells were then exposed to 0.4 mM H2O2 at 37 ºC and the number of hyphal formed were compared to hyphal formation when the cells were grown at 37 ºC only. However the results showed that oxidative stress failed to induce yeast to hyphal morphogenesis in this clinically isolated C. albicans strain.
Keywords: Candida albicans; oxidative stress
Kajian ini dijalankan untuk menentukan kesan suhu penggorengan yang berbeza terhadap kandungan lembapan dan lemak nuget ayam goreng bersalut. Tiga suhu penggorengan (150, 165 dan 180°C) pada dua tekanan penggorengan (102 dan 156 kPa) digunakan. Tiga jenis tepung penyalut (gandum, beras dan sagu) disediakan dengan nisbah pencairan tepung kepada air adalah 1:1.5 (gandum) dan 1:1 (beras dan sagu). Keputusan menunjukkan peningkatan suhu penggorengan menyebabkan pola penurunan kandungan lembapan bahagian salutan bagi nuget ayam yang disalut menggunakan tepung gandum dan beras. Tiada perbezaan yang signifikan bagi kandungan lembapan pada bahagian substrat untuk kesemua jenis tepung serta tekanan penggorengan. Kandungan lemak pula menunjukkan pola peningkatan pada bahagian salutan bagi setiap tekanan penggorengan dan jenis tepung salutan. Untuk bahagian substrat, walaupun kandungan lemak menunjukkan perbezaan yang signifikan, tetapi perbezaan ini adalah sangat kecil.
Kajian yang dijalankan ini bertujuan untuk melihat impak pengenalan instrumen derivatif ke atas kemeruapan pulangan saham di pasaran semerta. Kajian ini juga mengambil kira kesemua instrumen derivatif yang telah diperkenalkan di pasaran tempatan. Data harian bagi indeks komposit dan sebilangan indeks-indeks untuk setiap sektor akan digunakan di dalam kajian ini bagi mengkaji kesan secara keseluruhan dan mengikut sektor. Dengan menggunakan model GARCH terubahsuai iaitu dengan mengambil kira kesan perubahan struktur. Kajian ini mendapati wujudnya kesan yang bercampur-campur. Secara umumnya, pengenalan instrumen derivative mampu untuk mengurangkan tahap kemeruapan pulangan dan secara langsung menstabilkan pasaran saham. Tambahan pula, ia turut mempertingkatkan lagi kadar dan kualiti aliran maklumat ke dalam pasaran dan dengan demikian menjadikan pasaran saham bertambah efisien.
Kajian terhadap kesan suhu pengeringan (50, 60, 70oC) dan kepekatan garam (3, 5, 7%) terhadap kualiti ikan tongkol (Euthynnus affinis) telah dilakukan. Analisis kandungan proksimat menunjukkan nilai yang berbeza secara bererti (p<0.05), terutama kandungan protein (76.66%) ikan yang dikering pada suhu 50°C. Pengeringan pada suhu dan kepekatan garam yang tinggi cenderung untuk menghasilkan ikan tongkol kering dengan wama yang agak gelap (72.39). Ikon tongkol kering memiliki keupayaan memegang air yang rendah iaitu antara 3.43-3.66 ml/g sampel. Aktiviti air (aw) ikon tongkol yang hanya mencapai 0.76 atau kurang, merupakan tahap yang paling baik untuk tujuan penyimpanan, dan dapat mengawal pertumbuhan mikroorganisma, merencat aktiviti enzim dan memenuhi keperluan pembungkusan.
This study was carried out to determine the air quality in the mixed residential and industrial areas of Nilai, Negeri Sembilan based on the concentrations of sulphur dioxide (SO2) carbon monoxide (CO), nitrogen dioxide (NO2) and ozone (O3) gases as well as noise levels. Samplings were carried out for a total period of four days comprising two working and Monon-working days for each station from October 2004 until January 2005. Air Pollution Index (API) values showed that the air quality in these stations was moderately good. Secondary data were collected for PM10 The average concentration values of SO2 CO, NO2 and 03 were 0.024+0.021, 3.782±1.033, 0.0I3±0.009 and 0.026±0.008 ppm respectively. The results also showed that the concentrations of the pollutants were below their respective maximum permissible values stipulated by the Malaysian Department of Environment (DOE). Statistical analysis showed that there were no significant differences (p>0.05) of the pollutant levels between working days and non-working days. However, there were strong positive correlations between ozone gas and nitrogen dioxide levels (r=0.447, p<0.0l). There were a/so strong positive correlations between the concentration of co and the number of vehicles passing through (r= O. 690, p<0.0l). This study showed that the NO2 parameter was 92.35% close to the maximum permissible value set by the DOE. This could be due to anthropogenic activities. The noise levels recorded in this area were above the permissible limits set by the DOE.
This note describes a method for the determination of the peak-to-total ratio, P/T versus gamma-ray energy of range 59.54-1836.03 keV of a HPGe detector. Results show that this ratio decreases with energy. To check the validity of these results, two approaches of results comparison, namely with the ratio reported by Cesana and Terrani in year 1989 and with the shape of total efficiency reported by Debertin and Helmer in year 1988 were taken. lt is shown that this method gives satisfactory results since the obtained values of P/T and the shape of the total efficiency curve were in good agreement with the reported works. The precautional step that need to be taken when dealing with energy 59.54 keV 241Am source and the reason for taking the total efficiency as the evaluation tool are given.
Public perceptions, understanding and acceptance of modern biotechnology can both promote and hamper their commercial introduction and adoption. Various studies have shown that consumer acceptance of modern biotechnology tend to be conditional and dependent on several factors. Public perceptions of biotechnology have received extensive attention in recent years in most Western countries such as Europe, USA and Canada but there have been limited similar surveys in developing countries. Most of the earlier studies used uni-dimensional or bi-dimensional instrument with multi-items or the most is four dimensions with single item. In this study, public attitude towards genetically modified (GM) soybean that is already available in the Malaysian market. A survey was carried out on 577 general public respondents in the Klang Valley region. In order to detect the structure of attitude amongst the expert group in the Klang Valley region, structural equation modeling (SEM) using AMOS version 5.1 was carried out. Result of the survey has confirmed that attitude towards complex issues such as biotechnology should be seen as multi-faceted/ multidimensional process. The most important factors predicting encouragement of GM soybean are the specific application-linked perceptions about the benefits and acceptance of risk while moral concern, risk and familiarity are significant predictors of intermediate factors. Researchers, policy makers and industries interested in developing and marketing GM products in Malaysia should consider the various factors mentioned in this in order to gain public approval.
Tumbuhan yang mempunyai kelimpahan tinggi dan boleh mengumpul logam berat dengan banyak boleh digunakan sebagai bio-penunjuk. Tujuan kajian ini adalah untuk melihat kesesuaian Melastoma malabathricum sebagai bio-penunjuk bagi pencemar logam berat dalam tanih bekas lombong. Dalam kajian ini, lima belas sampel Melastoma malabathricum dan tanih telah diambil di tapak bekas lombong besi dan timah Pelepah Kanan Kota Tinggi, Johor. Tiga bahagian tumbuhan (akar, batang, daun) telah dianalisis untuk mengkaji penyerapan kandungan logam berat Cu, Fe dan Mn. Parameter tanih yang dikaji meliputi parameter fizikal dan kimia. Hasil kajian taburan saiz partikel tanih menunjukkan kebanyakan tanih di kawasan kajian adalah jenis berpasir dan bertekstur pasir berlom. Kandungan bahan organik adalah sekitar 1.45 hingga 5.91%. Nilai pH bagi tanih di kawasan kajian adalah sekitar 3.55 hingga 5.68 iaitu bersifat sangat asid ke asid. Kekonduksian elektrik tanih adalah antara 2.14 hingga 2.58 mS/cm. Hasil kajian menunjukkan bahawa, kepekatan logam-logam berat dalam tanih ialah 12070 hingga 65545 mg/kg bagi Fe, 1070.3 hingga 11956.3 mg/kg bagi Mn dan 386.5 hingga 4753.2 mg/kg bagi Cu. Kandungan logam-logam berat dalam bahagian-bahagian tumbuhan pula adalah mengikut turutan seperti berikut; Fe>Mn>Cu. Didapati bahawa spesies tumbuhan Melastoma malabathricurn adalah sesuai sebagai penunjuk biologi logam berat Fe dan Mn.
We report here the isolation and sequence analysis of a cDNA fragment for an endoglucanase gene from Aspergillus terreus SUK-I. A pair of primers was designed based on conserved regions of endoglucanase gene. Amplification of A. terreus SUK-I cDNA using the primers produced a DNA band of 642 bp. The cDNA fragment was purified and cloned into pCR®ll-TOPO plasmid vector. The cDNA insert was designated as SA2 and sequenced. Analysis of the SA2 sequence showed a high degree of identity towards endoglucanase gene sequences from A. aculeatus, A kawachii and Talaromyces emersonii. While, the putative amino acid sequence of SA2 showed 74 % identity towards endoglucanase protein from Thermoascus aurantiacus and 69 % identity towards endoglucanase protein from A. kawachii, A. niger, A. aculeatus and A. nidulans. A 66 % identity between SA2 putative amino acid sequence and A. oryzae endoglucanase protein sequence was also observed. Therefore, we concluded that SA2 codes for a putative endoglucanase gene of A. terreus SUK-I.
[Kami melaporkan di sini pemencilan dan analisis satu fragmen cDNA untuk gen endoglukanase daripada Aspergillus terreus SUK-I. Sepasang pencetus telah direkabentuk berasaskan kepada kawasan terpelihara gen endoglukanase. Amplifikasi cDNA A. terreus SUK-I menggunakan pencetus berkenaan menghasilkan satu jalur DNA bersaiz 642 pb. Fragmen cDNA berkenaan telah ditulenkan dan diklonkan ke dalam vektor plasmid pCR®II-TOPO. cDNA selitan telah dilabelkan sebagai SA2 dan dijujukkan. Analisis terhadap jujukan SA2 menunjukkan sebahagian daripada jujukan SA2 mempunyai darjah identiti yang tinggi terhadap jujukan gen endoglukanase daripada A. aculeatus, A. kawachii dan Talaromyces emersonii. Sementara, jujukan asid amino putatif SA2 menunjukkan identiti sebanyak 74% terhadap protein endoglukanase daripada Thermoascus aurantiacus dan identiti sebanyak 69% terhadap protein endoglukanase daripada A. kawachii, A. niger, A. aculeatus dan A. nidulans. ldentiti sebanyak 66% juga diperhatikan di antara jujukan asid amino putatif SA2 dan jujukan protein endoglukanase A. oryzae. Oleh itu, kami membuat kesimpulan bahawa SA2 mengkodkan gen putative endoglukanase A. terreus SUK-I].
Sebanyak dua puluh lima sampel tanih atas (0-15 cm) telah diambil dari enam stesen persampelan di kawasan Pulau Indah, Klang, Selangor. Sampel ini telah dianalisis untuk menentukan kandungan logam berat, ciri fiziko-kimia dan nutrien di dalam tanih. Tanih telah dikutip dari stesen berasingan berdasarkan jenis tanih dan aktiviti pembangunan gunatanah yang berlainan. Didapati bahawa tanih di kawasan kajian didominasi oleh tekstur pasir kecuali di Stesen 1 dan 6 yang didominasi oleh tekstur lempung. Kandungan nutrien tersedia dipengaruhi oleh jenis tanih, dengan purata kandungan K dan Mg tinggi dalam tanih lempung manakala purata kandungan PO tinggi dalam tanih pasir. Kandungan nutrien terlarut pula dipengaruhi oleh aktiviti gunatanah, dengan kandungan NO-N dan NH-N terlarut adalah tinggi di kawasan pertanian manakala kandungan SO terlarut pula tinggi di kawasan terminal minyak dan kawasan industri logam. Ciri kimia dipengaruhi oleh jenis tanih di mana pH, kapasiti pertukaran kation dan kandungan bahan organik lebih tinggi di dalam tanih lempung berbanding tanih pasir. Kandungan logam berat dipengaruhi oleh jenis guna tanah, dengan kandungan Pb dan Zn tinggi di kawasan pertanian. Kandungan As dan Co pula adalah tinggi di kawasan terminal minyak dan industri logam. Kawasan gudang menunjukkan bacaan yang tertinggi bagi Ni dan Cr manakala kawasan Pelabuhan Sarat menunjukkan bacaan Cu yang tertinggi. Secara keseluruhannya, kepekatan kandungan Pb, Cu, Ni dan Co masih berada di bawah paras yang berpotensi toksik dalam tanih manakala sebahagian dari nilai As, Cr dan Zn melebihi paras yang berpotensi toksik dalam tanih.
An integrated geoelectrical and geochemical techniques were used to investigate and delineate different types of groundwater in Kuala Selangor-Batang Berjuntai alluvial aquifer. Previous hydrogeological borehole investigations showed that this aquifer contained several types of groundwater in relation to its salinity. The high salinity of the groundwater in some areas was believed to be due to either saltwater intrusion from the nearby sea or river infiltration during tide season. Both vertical electrical sounding (VES) and 2-D electrical resistivity imaging methods were employed to study and map the subsurface variation of resistivity in the area. For each measurement, a total spread length of 200 m was obtained with vertical depth penetration of about 60 to 100 m. Chemical analysis data of the groundwater samples taken from both shallow and deep boreholes were used in the interpretation of the groundwater interfaces. A total of 45 VES stations were succesfully established along three parallel roads with direction almost perpendicular to the coastal line. The distance between stations vary from 1 - 2 km with a maximum length of about 60 km surveyed line. Results of the vertical electrical soundings and resistivity imaging as well as the chemistry of the groundwater samples showed that groundwater in the study area can be grouped into three types i.e. fresh water (resistivity >100 Ωm.), brackish water (5-100 Ωm.) and salt water (resisitvity <5 Ωm.). The subsurface resistivity sections derived from the VES study suggest that the boundary between fresh and salt water was located between 4 to 8 km from the present coastal line. This result appears to agree well with the groundwater interfaces obtained from the chloride concentration map. Values greater than 300 ppm was considered to be representing zone of brackish water whilst values greater than 800 ppm represents saline water zones.
Kajian pemegunan enzim peroksidase dalam membran hibrid sol-gel-kitosan untuk penyediaan transduser optik hidrogen peroksida telah dilakukan dalam pembinaan biosensor. Kajian ini merangkumi pengoptimuman nisbah sol-gel-kitosan, pencirian enzim dalam larutan bebas dan pemegunan enzim dalam hibrid sol-gel-kitosan serta penciriannya. Spektrum serapan bagi setiap pencirian ditentukan menggunakan Spektrofotometer uL-Nampak. Hasil kajian menunjukkan aktiviti enzim tidak berubah selepas pemegunan. Nisbah optimum hibrid sol-gel-kitosan adalah 4:6. Nilai sisihan piawai relatif (RSD) untuk kebolehulangan kaedah ini adalah 2.71% dan 3.76%, masing-masingnya untuk enzim bebas dan enzim terpegun.
The possible presence of 10 organochlorine insecticides (aldrin, heptachlor, lindane, endosulfan, p,p’-DDE, p,p-DDT, methoxychlor, chlordane, endrin and dieldrin) in the sediment and water of a lake and river that flow through the Kelab Danau UKM were examined. Altogether six sampling sites were surveyed and three samplings within a period of three months were carried out in 2001. The insecticides were analysed by using gas chromatography equipped with an electron capture detector. The results showed that endrin, chlordane and aldrin were present in all water samples with concentrations for endrin: 0.02-0.21 µg/L, chlordane: 0.05-0.16 µg/L and aldrin: 0.03-0.13 µg/L. Lindane and heptachlor were rarely detected in the water samples. For sediment, lindane, endrin and heptachlor were detected in all sediment samples. Their levels in sediments were 0.28-0.53 µg/kg for lindane, 0.06-0.53 µg/kg for heptachlor and 1.06-2.06 µg/kg for endrin. Insecticides such as p,p' -DDE, p,p-DDT, methoxychlor, endosulfan and dieldrin were not detected in sediments or water during most samplings. The presence of organochlorine insecticides in the aquatic environment of the golf club area may be attributed to the input from usage. Another source would be from the river upstream outside the golf club flow through an area of oil palm plantation, where these insecticides might have been used for pest control in the past.
In the original ElGamal signature scheme and it’s variants, two secret integers-private key and one-time secret key are required to produce a signature on a message, m. The private key of a system will be used throughout the life of the system whereas the one-time secret key only be used once and must be regenerated (different one-time secret key) when signing different message. This paper introduces a new version of ElGamal signature that eliminates the use of one-time secret key. This property will make all attacks, aiming at revealing the one-time secret key irrelevant. The scheme also can be regarded as ‘a right notion of signature scheme’ because we use only one secret key to sign messages.
Experiments were carried out to establish optimum culture condition and to identify the most responsive hypocotyls segments to regenerate shoots in the presence of slight callus for the local cabbage cultivar, Brassica oleracea L. var capitata subvar. kkcross. Results of the study showed that only the upper segment of the hypocotyls (1 cm and 2 cm from both shoot apex) excised from in vitro seedlings, regenerate shoots while the segment nearest to the apex (1 cm) regenerate both shoots and roots. Optimum regeneration was obtained when the seedlings' age were 3 weeks old as compared to younger or older explants. Types of culture vessels did not exhibit any significant effect on the hypocotyls culture. Multiple shoots with the presence of slight healthy callus (0.5 - 2.0mm diameter) were successfully regenerated at a frequency of 42 and 50% respectively from hypocotyls sections cultured on a basal Murashige and Skoog (MS) medium supplemented with 3-lndole acetic acid (1AA) [1 µg/L (w/v)], kinetin [2 µg/L(w/v)] and casein hydrolysate [500 µg/L(w/ v)] (designated as Ms1 medium) and B5 medium supplemented with adenine sulphate [40 mg/L(w/v)], glutamine (6mM) and 2, 4,5-trichlorophenoxyacetic acid [2,4,5- T (0.1 mg/L( w/v)] (designated as cs23 medium). Clonal propagation from axillary buds was induced on a basal MS medium supplemented with low concentration of kinetin [0.05-0.2mg/L(w/v)]. Plantlets with complete roots were successfully transferred into a mixture of soil and vermiculate (1: 1) and grown into normal mature cabbage plants in the glasshouse.
Variations in leaf photosynthetic, morphological and biochemical properties with increasing plant height from seedlings to emergent trees were investigated in five dipterocarp species in a Malaysian tropical rain forest. Canopy openness increased significantly with tree height. Photosynthetic properties, such as photosynthetic capacity at light saturation, light compensation point, maximum rate of carboxylation and maximum rate of photosynthetic electron transport, all increased significantly with tree height. Leaf morphological and biochemical traits, such as leaf mass per area, palisade layer thickness, nitrogen concentration per unit area, chlorophyll concentration per unit dry mass and chlorophyll to nitrogen ratio, also changed significantly with tree height. Leaf properties had simple and significant relationships with tree height, with few intra- and interspecies differences. Our results therefore suggest that the photosynthetic capacity of dipterocarp trees depends on tree height, and that the trees adapt to the light environment by adjusting their leaf morphological and biochemical properties. These results should aid in developing models that can accurately estimate carbon dioxide flux and biomass production in tropical rain forests.
NCD Risk Factors in Malaysia. Putrajaya: Ministry of Health, Malaysia, 2006
Study name: Malaysia Non-Communicable Disease Surveillance-1 (MyNCDS-1) survey
MeSH terms: Adult; Alcohol Drinking; Chronic Disease; Cross-Sectional Studies; Diabetes Mellitus; Diet; Health Surveys; Humans; Hypertension; Malaysia; Risk Factors; Smoking; Body Mass Index; Prevalence; Dyslipidemias; Waist Circumference
In recent years, infection of the stomach with the organism Helicobacter Pylori has been found to be the main cause of gastric ulcers, one of the common ailments afflicting humans. Excessive acid secretion in the stomach, reduction in gastric mucosal blood flow, constant intake of non-steroid anti-inflammatory drugs (NSAIDS), ethanol, smoking, stress etc. are also considered responsible for ulcer formation. The prevalent notion among sections of population in this country and perhaps in others is that "red pepper" popularly known as "Chilli," a common spice consumed in excessive amounts leads to "gastric ulcers" in view of its irritant and likely acid secreting nature. Persons with ulcers are advised either to limit or avoid its use. However, investigations carried out in recent years have revealed that chilli or its active principle "capsaicin" is not the cause for ulcer formation but a "benefactor." Capsaicin does not stimulate but inhibits acid secretion, stimulates alkali, mucus secretions and particularly gastric mucosal blood flow which help in prevention and healing of ulcers. Capsaicin acts by stimulating afferent neurons in the stomach and signals for protection against injury causing agents. Epidemiologic surveys in Singapore have shown that gastric ulcers are three times more common in the "Chinese" than among Malaysians and Indians who are in the habit of consuming more chillis. Ulcers are common among people who are in the habit of taking NSAIDS and are infected with the organism "Helicobacter Pylori," responsible for excessive acid secretion and erosion of the mucosal layer. Eradication of the bacteria by antibiotic treatment and avoiding the NSAIDS eliminates ulcers and restores normal acid secretion.
Design and construction of buildings used to be on framed structure
incorporating reinforced concrete, steel or timber as structural member to
transmit load to the foundation. Bricks are normally used as infill materials in
these framed structures. However, research has shown that bricks can also be
used as external and internal masonry bearing walls. With the use of structural
masonry construction method, cheaper and faster construction can be achieved.
Savings are obtained by using less formwork and reinforcing steel, reducing
construction time as lesser frames or none are used, and eliminating waiting
time for the structural concrete to cure or gain their strength. Calcium silicate
and sand cement bricks were tested for their mechanical properties.
Investigations were carried out on six masonry bearing walls. Each unit
measured 1000 mm × 1000 mm and a half brick thick. The structural behaviour
due to compressive axial load was investigated and it shows that both bricks
satisfy the requirement as load bearing wall. However, the study concluded
that sand cement brick wall showed better performance, with maximum lateral
displacement of 3.81mm, vertical deflection of 6.63 mm and ultimate load of
448.13 kN.