Browse publications by year: 2013

Upgrading producer gas quality from rubber wood gasification in a radio frequency tar thermocatalytic treatment reactor

Anis S, Zainal ZA

Bioresour Technol, 2013 Dec;150:328-37.
PMID: 24185417 DOI: 10.1016/j.biortech.2013.10.010

This study focused on improving the producer gas quality using radio frequency (RF) tar thermocatalytic treatment reactor. The producer gas containing tar, particles and water was directly passed at a particular flow rate into the RF reactor at various temperatures for catalytic and thermal treatments. Thermal treatment generates higher heating value of 5.76 MJ Nm(-3) at 1200°C. Catalytic treatments using both dolomite and Y-zeolite provide high tar and particles conversion efficiencies of about 97% on average. The result also showed that light poly-aromatic hydrocarbons especially naphthalene and aromatic compounds particularly benzene and toluene were still found even at higher reaction temperatures. Low energy intensive RF tar thermocatalytic treatment was found to be effective for upgrading the producer gas quality to meet the end user requirements and increasing its energy content.

MeSH terms: Biotechnology/instrumentation*; Calcium Carbonate/chemistry; Catalysis; Gases/chemistry*; Hot Temperature*; Magnesium/chemistry; Radio Waves*; Rubber/chemistry*; Tars/chemistry*; Wood/chemistry*; Zeolites/chemistry
Abstracts of the 24th Regional Congress of the International Society of Blood Transfusion in conjunction with the 6th Malaysian National Transfusion Medicine Conference of the Malaysian Blood Transfusion Society. Kuala Lumpur, Malaysia. December 1-4, 2013

Vox Sang, 2013 Dec;105 Suppl 2:1-139.
PMID: 24176003 DOI: 10.1111/vox.12100_1
MeSH terms: Blood Transfusion*; Humans
Fulltext Ingestion of honey improves the symptoms of allergic rhinitis: evidence from a randomized placebo-controlled trial in the East coast of Peninsular Malaysia

Asha'ari ZA, Ahmad MZ, Jihan WS, Che CM, Leman I

Ann Saudi Med, 2013;33(5):469-75.
PMID: 24188941 DOI: 10.5144/0256-4947.2013.469

BACKGROUND AND OBJECTIVES: The role of honey in the treatment of allergic rhinitis (AR) is controversial. We studied the complementary effect of ingestion of a high dose of honey, in addition to standard medications, on AR.
DESIGN AND SETTINGS: Prospective randomized placebo-controlled study. Subjects were recruited from an otolaryngology clinic in 2 tertiary referral centers in the East coast of Peninsular Malaysia. The study period ranged from April 2010-April 2011.
METHODS: Forty AR patients were divided equally into a case group and a control group. All the subjects received a daily dose of 10 mg of loratadine for 4 weeks. The case group ingested 1 g/kg body weight of honey daily in separate doses for the 4-week period. The control group ingested the same dose of honey-flavored corn syrup as placebo. AR symptoms were scored at the start, week 4, and week 8 of the study.
RESULTS: There were no significant differences between the mean total symptom score of the case and the control groups at the start of the study. At week 4, both groups showed progressive improvement in the symptoms; at week 8, only the case group showed a continuous improvement in the symptom score. Only the group that ingested honey showed a significant improvement in individual AR symptoms. The improvement persisted for a month after the cessation of the treatment.
CONCLUSION: Honey ingestion at a high dose improves the overall and individual symptoms of AR, and it could serve as a complementary therapy for AR.

MeSH terms: Adult; Double-Blind Method; Female; Honey*; Humans; Malaysia; Male; Middle Aged; Prospective Studies; Rhinitis, Allergic, Perennial/therapy*; Time Factors; Treatment Outcome; Loratadine/administration & dosage; Loratadine/therapeutic use*; Anti-Allergic Agents/administration & dosage; Anti-Allergic Agents/therapeutic use*; Young Adult; Rhinitis, Allergic
Fulltext Human and animal invasive muscular sarcocystosis in Malaysia--recent cases, review and hypotheses

Tappe D, Abdullah S, Heo CC, Kannan Kutty M, Latif B

Trop Biomed, 2013 Sep;30(3):355-66.
PMID: 24189667

Sarcocystosis, an unusual parasitic zoonotic disease, is caused by coccidian/ apicomplexan protozoa in humans and animals. The parasites usually develop in a heteroxenous predator-prey life-cycle involving final (carnivore) and intermediate (omnivore/herbivore) hosts. Besides the intestinal, non-invasive form of the disease in which humans and animals are the definitive hosts for certain Sarcocystis spp., the invasive form has come to recent attention. In the latter, humans and animals serve as intermediate host harbouring sarcocysts in their muscle tissue. Already in 1991 sarcocystosis was seen as a potential emerging food borne zoonosis in Malaysia, and in 2011 and 2012 the largest cluster of symptomatic human muscular sarcocystosis world-wide was reported from Tioman Island, Pahang state. In this review, we focus on invasive sarcocystosis in humans and animals in Malaysia, review the recorded cases and epidemiology, and present hypotheses.

MeSH terms: Animals; Foodborne Diseases/epidemiology*; Foodborne Diseases/parasitology; Foodborne Diseases/pathology; Foodborne Diseases/veterinary*; Humans; Malaysia/epidemiology; Sarcocystis/isolation & purification*; Sarcocystosis/epidemiology*; Sarcocystosis/parasitology; Sarcocystosis/pathology; Sarcocystosis/veterinary*; Zoonoses/epidemiology*; Zoonoses/parasitology; Zoonoses/pathology
Fulltext Colonial morphotypes and biofilm forming ability of Burkholderia pseudomallei

Koh SF, Tay ST, Puthucheary SD

Trop Biomed, 2013 Sep;30(3):428-33.
PMID: 24189672 MyJurnal

Burkholderia pseudomallei the causative agent of melioidosis, is being increasingly recognized as an important cause of morbidity and mortality in South East Asia. Biofilm formation of B. pseudomallei may be responsible for dormancy, latency and relapse of melioidosis. Based on the colonial morphology of the bacteria on B. pseudomallei selective agar medium, seven distinct morphotypes were identified. This study was conducted to assess the in vitro biofilm produced by B. pseudomallei and to investigate possible correlation between B. pseudomallei morphotypes with biofilm forming abilities of the isolates. Using a standard biofilm crystal violet staining assay, comparison was made between the biofilm forming ability of 76 isolates of B. pseudomallei and Burkholderia thailandensis ATCC 700388. Amongst the blood isolates, 30.2% were considered as high biofilm producers and 27.9% were low producers, 33.3% of the pus isolates were considered as high and 16% low biofilm producers. Most of the isolates were identified as morphotype group 1 which displayed a rough centre with irregular circumference on the agar medium. However, we did not find any correlation of B. pseudomallei morphotypes with biofilm forming abilities (p > 0.05). Additional studies are needed to identify internal and external factors which contribute to the high and low biofilm formation of B. pseudomallei.

MeSH terms: Bacteriological Techniques/methods; Blood/microbiology; Culture Media/chemistry; Humans; Melioidosis/microbiology; Phenotype; Staining and Labeling/methods; Suppuration/microbiology; Burkholderia pseudomallei/growth & development; Burkholderia pseudomallei/isolation & purification; Burkholderia pseudomallei/physiology*; Biofilms/growth & development*
Fulltext Active infection and morphometric study of Trypanosoma evansi among horses in Peninsula Malaysia

Elshafie EI, Sani RA, Hassan L, Sharma R, Bashir A, Abubakar IA

Trop Biomed, 2013 Sep;30(3):444-50.
PMID: 24189674 MyJurnal

Apart from occasional reports of clinical disease affecting horses, there is no information about Trypanosoma evansi in horses in Peninsula Malaysia. Thus, a cross-sectional study was conducted in eight states in Peninsula Malaysia to determine the active presence of T. evansi in horses. A total of 527 blood samples were obtained and examined by haematocrit centrifugation technique (HCT), Giemsa-stained thin blood smear (GSS), morphometric measurements, polymerase chain reaction (PCR) and cloning of PCR products. The results showed an overall parasitological prevalence of 0.57% (3/527, CI: 1.6-0.19%) with both HCT and GSS. Morphometric study revealed the mean total length of the trypanosomes including the free flagellum was 27.94 ± 2.63 μm. PCR successfully amplified a trypanosome specific 257 bp in 1.14% of samples (6/527, CI: 2.4-0.52%) and was confirmed by nucleotide sequences. The mean packed cell volume (PCV) for the positive cases detected by HCT was lower (23% ± 7.00) compared to the positive cases detected by PCR alone in the state of Terengganu (35% ± 4.73). In conclusion, this study showed T. evansi infection occurred in low frequency in horses in Peninsula Malaysia, and anaemia coincided with parasitaemic animals. PCR is considered as a sensitive diagnostic tool when parasitaemia is undetectable. The slight lengthier mean of parasite and anaemia may indicate a virulent strain of T. evansi circulating throughout the country. Thus, it's highly recommended to shed light on host-parasite relationship for better epidemiological understanding.

MeSH terms: Anemia/diagnosis; Anemia/etiology; Anemia/veterinary; Animals; Blood/parasitology; Horse Diseases/epidemiology*; Horse Diseases/parasitology; Horse Diseases/pathology; Horses; Malaysia; Parasitology/methods; Trypanosoma/cytology; Trypanosoma/genetics; Trypanosoma/isolation & purification*; Trypanosomiasis/complications; Trypanosomiasis/epidemiology; Trypanosomiasis/parasitology; Trypanosomiasis/veterinary*; Veterinary Medicine/methods; Prevalence; Clinical Laboratory Techniques/methods
Fulltext Comparison of two nested PCR methods for the detection of human malaria

Anthony C, Mahmud R, Lau YL, Syedomar SF, Sri La Sri Ponnampalavanar S

Trop Biomed, 2013 Sep;30(3):459-66.
PMID: 24189676 MyJurnal

Battling malaria will be a persistent struggle without the proper means to diagnose the parasitic infection. However, the inherent limitations of microscopy, the conventional method of diagnosing malaria, affect the accuracy of diagnosis. The present study aimed to compare the accuracy of two different set of primers targeting the small subunit ribosomal RNA (ssRNA) and the dihydrofolate reductase-thymidylate synthase linker region (dhfr-ts) in detecting species specific malaria infections by nested PCR. The sensitivity and specificity of nested PCR assay using the two primers were calculated with reference to microscopy as the 'gold standard'. The results show that 18S rRNA primers had 91.9% sensitivity and 100% specificity in detecting human Plasmodium species as opposed to dhfr-ts primers which had 51.4% sensitivity and 100% specificity. The higher sensitivity of 18S rRNA primers suggests that it may be a better diagnostic tool for detecting human malaria.

MeSH terms: Humans; Malaria/diagnosis*; Plasmodium/genetics; Plasmodium/isolation & purification*; RNA, Ribosomal/genetics; Sensitivity and Specificity; Tetrahydrofolate Dehydrogenase/genetics; Thymidylate Synthase/genetics; Polymerase Chain Reaction/methods*; DNA Primers/genetics; DNA, Intergenic; Molecular Diagnostic Techniques/methods*
Fulltext Phytochemical analysis of Andrographis paniculata and Orthosiphon stamineus leaf extracts for their antibacterial and antioxidant potential

Malahubban M, Alimon AR, Sazili AQ, Fakurazi S, Zakry FA

Trop Biomed, 2013 Sep;30(3):467-80.
PMID: 24189677 MyJurnal

Leaves of Andrographis paniculata and Orthosiphon stamineus were extracted with water, ethanol, methanol and chloroform to assess their potential as antibacterial and antioxidant agents. High performance liquid chromatography analysis showed that the methanolic extracts of A. paniculata and O. stamineus leaves gave the highest amounts of andrographolide and rosmarinic acid, respectively. These leaf extracts exhibited antimicrobial and antioxidant activities and, at the highest concentration tested (200 mg/mL), showed greater inhibitory effects against the Gram positive bacteria Bacillus cereus and Staphylococcus aureus than 10% acetic acid. Andrographis paniculata and O. stamineus methanolic and ethanolic leaf extracts also showed the strongest antioxidant activity as compared with the other extracts tested. The bioactive compounds present in these leaf extracts have the potential to be developed into natural antibacterial and antioxidant agents that may have applications in animal and human health.

MeSH terms: Anti-Bacterial Agents/isolation & purification; Anti-Bacterial Agents/pharmacology*; Antioxidants/isolation & purification; Antioxidants/pharmacology*; Bacillus cereus/drug effects; Chromatography, High Pressure Liquid; Cinnamates/analysis; Diterpenes/analysis; Free Radicals/metabolism; Microbial Sensitivity Tests; Plant Extracts/isolation & purification; Plant Extracts/pharmacology*; Staphylococcus aureus/drug effects; Superoxides/metabolism; Plant Leaves/chemistry; Orthosiphon/chemistry*; Andrographis/chemistry*; Depsides/analysis; Phytochemicals/isolation & purification; Phytochemicals/pharmacology*
Fulltext Adult carrion arthropod community in a tropical rainforest of Malaysia: analysis on three common forensic entomology animal models

Azwandi A, Nina Keterina H, Owen LC, Nurizzati MD, Omar B

Trop Biomed, 2013 Sep;30(3):481-94.
PMID: 24189678 MyJurnal

Decomposing carrion provides a temporary microhabitat and food source for a distinct community of organisms. Arthropods constitute a major part of this community and can be utilized to estimate the postmortem interval (PMI) of cadavers during criminal investigations. However, in Malaysia, knowledge of carrion arthropod assemblages and their succession is superficial. Therefore, a study on three types of forensic entomology animal model was conducted from 27 September 2010 to 28 October 2010 in a tropical rainforest at National University of Malaysia, Bangi, Selangor, Malaysia. Over one month collections of arthropods were made on nine animal carcasses: three laboratory rats (Rattus norvegicus, mean weight: 0.508 ± 0.027 kg), three rabbits (Oryctolagus cuniculus, mean weight: 2.538 ± 0.109 kg) and three long tailed macaque (Macaca fascicularis, mean weight: 5.750 ± 0.551 kg). A total of 31,433 arthropods belonging to eight orders and twenty-eight families were collected from all carcasses. Among 2924 of adults flies collected, approximately 19% were calliphorids with Chrysomya megacephala (Fabricius, 1794) being the most abundant. Arthropod taxon richness was lower on rat carcasses compared to that of rabbit and monkey carcasses, and this was more apparent during the first week of decomposition. However, there were no significant differences in Shannon-Weiner index (H'), Simpson dominance index (C) and Pielou's Evenness index (J) between different animal model. The arthropod assemblages associated to animal model were different significantly (p<0.05) while decomposition stage was a significant factor influencing insect assemblages (p<0.05). Analysis on the arthropods succession indicated that some taxa have a clear visitation period while the others, particularly Coleoptera, did not show a clear successional pattern thus require futher insect succession study. Although human bodies were not possible for the succession study, most of the arthropods collected are necrophagous, and will also possibly colonize human cadaver, and potentially be useful in assisting in estimates of PMI in future forensic cases in Malaysia.

MeSH terms: Animals; Arthropods/growth & development*; Cadaver*; Entomology/methods*; Forensic Medicine/methods*; Macaca; Malaysia; Rabbits; Time Factors; Tropical Climate; Animal Experimentation; Rats
Fulltext Evaluation of enhanced virgin coconut oil and senduduk (Melastoma malabathricum) as anthelmintics against caprine strongyle nematodes

Basripuzi HB, Sani RA, Ariff OM, Chandrawathani P

Trop Biomed, 2013 Sep;30(3):516-25.
PMID: 24189681 MyJurnal

A study was conducted to evaluate the anthelmintic properties of enhanced virgin coconut oil (EVCO) and senduduk (Melastoma malabathricum) plant against strongyle nematodes in goats. Two preparations of 10% EVCO dissolved in 90% virgin coconut oil and 10% EVCO dissolved in 90% palm oil, were given orally to two groups of mixed breeds goats. The efficacy test indicated that EVCO was insufficiently active as an anthelmintic. Four concentrations of senduduk solution (1.25, 2.5, 5.0 and 10 mg ml(-1)) were compared with a control and albendazole in an in vitro test for larvicidal effect. There was no significant larval mortality using senduduk solution. An in vivo test of senduduk was conducted by comparing three groups of goats, namely control, levamisole and treatment groups that were given a daily oral dose of senduduk crude extract with 1g kg(-1) from Day 0 to Day 12 and 2 g kg(-1) from Day 13 to Day 30. This efficacy test with senduduk also gave negative results. The findings obtained indicated that EVCO and senduduk were ineffective as anthelmintics against caprinestrongyle nematodes at the concentrations used.

MeSH terms: Administration, Oral; Animals; Anthelmintics/isolation & purification; Anthelmintics/pharmacology; Anthelmintics/therapeutic use*; Female; Goats; Male; Plant Extracts/isolation & purification; Plant Extracts/pharmacology; Plant Extracts/therapeutic use*; Plant Oils/isolation & purification; Plant Oils/pharmacology; Plant Oils/therapeutic use*; Goat Diseases/drug therapy*; Treatment Outcome; Strongylida/drug effects; Strongylida/isolation & purification; Strongylida Infections/drug therapy; Strongylida Infections/parasitology; Strongylida Infections/veterinary; Parasitic Sensitivity Tests; Melastomataceae/chemistry*
Fulltext Zoonotic parasites from exotic meat in Malaysia

Fazly ZA, Nurulaini R, Shafarin MS, Fariza NJ, Zawida Z, Muhamad HY, et al.

Trop Biomed, 2013 Sep;30(3):535-42.
PMID: 24189683 MyJurnal

Four zoonotic parasites, Sarcocystis spp., Toxoplasma gondii, Trichinella spp. and Taenia spp were screened in exotic meats. A total of forty-six (n=46) meat samples from various species of exotic animals were received from all the 14 states in Malaysia from January 2012 to April 2012. All exotic meat samples were examined macroscopically and histologically for the four zoonotic parasites. Results by histological examination of exotic meats showed the presence of Sarcocystis and Toxoplasma cysts at 8.7% (n=4) and 4.3% (n=2) respectively. No Trichinella spp. and Taenia spp. were found.

MeSH terms: Animals; Histocytochemistry; Malaysia; Meat/parasitology*; Parasites/classification*; Parasites/isolation & purification*; Parasitology
Fulltext A preliminary field survey of ectoparasites of rodents in urban park, Sarawak, Malaysian Borneo

Madinah A, Mariana A, Fatimah A, Abdullah MT

Trop Biomed, 2013 Sep;30(3):547-51.
PMID: 24189685 MyJurnal

A survey of ectoparasites was carried out during Eco-Zoonoses Expedition in Bukit Aup Jubilee Park (BAJP), Sibu, Sarawak, Malaysian Borneo from 5(th) to 9(th) June 2008. A total of nine individuals comprising two species of rodents were captured. The species of rodents screened for ectoparasites were Sundamys muelleri and Callosciurus notatus. Four genera and six species of ectoparasites were collected, namely, Ixodes granulatus, Ixodes sp., Laelaps sedlaceki, Laelaps nuttalli, Hoplopleura dissicula and Listrophoroides sp. Three species of the ectoparasites are known to have potential health risk. The species were Ixodes granulatus, Laelaps nuttalli and Hoplopleura dissicula. This survey produced the first list of ectoparasites in Bukit Aup Jubilee Park, Sarawak, Malaysia.

MeSH terms: Animals; Arthropods/classification*; Ectoparasitic Infestations/epidemiology; Ectoparasitic Infestations/parasitology; Ectoparasitic Infestations/veterinary*; Malaysia/epidemiology; Microscopy; Rodent Diseases/epidemiology*; Rodent Diseases/parasitology*; Sciuridae/parasitology*; Murinae/parasitology*
Photocatalytic degradation of resorcinol, an endocrine disrupter, by TiO2 and ZnO suspensions

Lam SM, Sin JC, Abdullah AZ, Mohamed AR

Environ Technol, 2013 May-Jun;34(9-12):1097-106.
PMID: 24191441

In the work presented here, photocatalytic systems using TiO2 and ZnO suspensions were utilized to evaluate the degradation of resorcinol (ReOH). The effects of catalyst concentration and solution pH were investigated and optimized using multivariate analysis based on response surface methodology. The results indicated that ZnO showed greater degradation and mineralization activities compared to TiO2 under optimized conditions. Using certain radical scavengers, a positive hole, together with the participation of hydroxyl radicals, were the oxidative species responsible for ReOH degradation on TiO2 whereas, the ZnO photocatalysis occurred principally via hydroxyl radicals. Some hitherto unreported pathway intermediates of ReOH degradation were identified using gas chromatography-mass spectrometry. A tentative reaction mechanism for the formation of these intermediates was proposed. Moreover, the figure-of-merit electrical energy per order was employed to estimate the electrical energy consumption.

MeSH terms: Analysis of Variance; Industrial Waste; Models, Molecular; Research Design; Resorcinols/analysis; Resorcinols/chemistry*; Titanium/chemistry*; Water Pollutants, Chemical/analysis; Water Pollutants, Chemical/chemistry*; Zinc Oxide/chemistry*; Endocrine Disruptors/analysis; Endocrine Disruptors/chemistry*; Environmental Restoration and Remediation/methods*; Photochemical Processes
Antiulcer activity of Muntingia calabura leaves involves the modulation of endogenous nitric oxide and nonprotein sulfhydryl compounds

Balan T, Mohd Sani MH, Suppaiah V, Mohtarrudin N, Suhaili Z, Ahmad Z, et al.

Pharm Biol, 2013 Nov 05.
PMID: 24192248

Abstract Context: Muntingia calabura L. (Muntingiaceae) is a native plant species of the American continent and is widely cultivated in warm areas in Asia, including Malaysia. The plant is traditionally used to relieve pain from gastric ulcers. Objective: This study was designed to determine the antiulcer activity of a methanol extract of M. calabura leaves (MEMC) and the possible mechanisms of action involved. Materials and methods: An acute toxicity study was conducted using a single oral dose of 2000 mg/kg MEMC. The antiulcer activity of MEMC was evaluated in absolute ethanol- and indomethacin-induced gastric ulcer rat models. MEMC was administered orally (dose range 25-500 mg/kg) to rats fasted for 24 h. The animals were pretreated with NG-nitro-l-arginine methyl esters (l-NAME) or N-ethylmaleimide (NEM) prior to MEMC treatment to assess the possible involvement of endogenous nitric oxide (NO) and nonprotein sulfhydryl (NP-SH) compounds in the gastroprotective effect of MEMC. Results: As the administered dose did not cause toxicity in the rats, the oral median lethal dose (LD50) of MEMC was >2000 mg/kg in rats. MEMC exerted significant (p
Fulltext Identification of parvalbumin and two new thermolabile major allergens of Thunnus tonggol using a proteomics approach

Rosmilah M, Shahnaz M, Meinir J, Masita A, Noormalin A, Jamaluddin M

Int Arch Allergy Immunol, 2013;162(4):299-309.
PMID: 24193115 DOI: 10.1159/000354544

The longtail tuna (Thunnus tonggol) is widely consumed in Asia. Parvalbumin, the main major allergen of fish, has been well identified in multiple fish species, yet little is known about the allergenic proteins in T. tonggol. Thus, the aim of this study was to characterize the major allergens of T. tonggol using a proteomics approach.

MeSH terms: Allergens/analysis*; Allergens/immunology; Animals; Electrophoresis, Polyacrylamide Gel; Food Hypersensitivity/diagnosis; Food Hypersensitivity/immunology*; Humans; Immunoglobulin E/blood; Immunoglobulin E/immunology; Parvalbumins/analysis*; Parvalbumins/immunology; Mass Spectrometry; Tuna/immunology*; Immunoblotting; Electrophoresis, Gel, Two-Dimensional; Fish Proteins/immunology; Fish Proteins/chemistry*; Proteomics/methods*
Security analysis of a chaotic map-based authentication scheme for telecare medicine information systems

Yau WC, Phan RC

J Med Syst, 2013 Dec;37(6):9993.
PMID: 24194093 DOI: 10.1007/s10916-013-9993-9

Many authentication schemes have been proposed for telecare medicine information systems (TMIS) to ensure the privacy, integrity, and availability of patient records. These schemes are crucial for TMIS systems because otherwise patients' medical records become susceptible to tampering thus hampering diagnosis or private medical conditions of patients could be disclosed to parties who do not have a right to access such information. Very recently, Hao et al. proposed a chaotic map-based authentication scheme for telecare medicine information systems in a recent issue of Journal of Medical Systems. They claimed that the authentication scheme can withstand various attacks and it is secure to be used in TMIS. In this paper, we show that this authentication scheme is vulnerable to key-compromise impersonation attacks, off-line password guessing attacks upon compromising of a smart card, and parallel session attacks. We also exploit weaknesses in the password change phase of the scheme to mount a denial-of-service attack. Our results show that this scheme cannot be used to provide security in a telecare medicine information system.

MeSH terms: Algorithms; Confidentiality/standards*; Humans; Computer Security/standards*; Electronic Health Records/standards; Health Information Exchange/standards*
Fulltext An inhibitive enzyme assay to detect mercury and zinc using protease from Coriandrum sativum

Baskaran G, Masdor NA, Syed MA, Shukor MY

ScientificWorldJournal, 2013;2013:678356.
PMID: 24194687 DOI: 10.1155/2013/678356

Heavy metals pollution has become a great threat to the world. Since instrumental methods are expensive and need skilled technician, a simple and fast method is needed to determine the presence of heavy metals in the environment. In this study, an inhibitive enzyme assay for heavy metals has been developed using crude proteases from Coriandrum sativum. In this assay, casein was used as a substrate and Coomassie dye was used to denote the completion of casein hydrolysis. In the absence of inhibitors, casein was hydrolysed and the solution became brown, while in the presence of metal ions such as Hg²⁺ and Zn²⁺, the hydrolysis of casein was inhibited and the solution remained blue. Both Hg²⁺ and Zn²⁺ exhibited one-phase binding curve with IC₅₀ values of 3.217 mg/L and 0.727 mg/L, respectively. The limits of detection (LOD) and limits of quantitation (LOQ) for Hg were 0.241 and 0.802 mg/L, respectively, while the LOD and LOQ for Zn were 0.228 and 0.761 mg/L, respectively. The enzyme exhibited broad pH ranges for activity. The crude proteases extracted from Coriandrum sativum showed good potential for the development of a rapid, sensitive, and economic inhibitive assay for the biomonitoring of Hg²⁺ and Zn²⁺ in the aquatic environments.

MeSH terms: Colorimetry/methods*; Environmental Monitoring/methods*; Environmental Pollutants/analysis; Mercury/analysis*; Peptide Hydrolases/chemistry*; Protease Inhibitors/analysis*; Zinc/analysis*; Coriandrum/enzymology*
Fulltext Semisolid metal processing techniques for nondendritic feedstock production

Mohammed MN, Omar MZ, Salleh MS, Alhawari KS, Kapranos P

ScientificWorldJournal, 2013;2013:752175.
PMID: 24194689 DOI: 10.1155/2013/752175

Semisolid metal (SSM) processing or thixoforming is widely known as a technology that involves the formation of metal alloys between solidus and liquidus temperatures. For the procedure to operate successfully, the microstructure of the starting material must consist of solid near-globular grains surrounded by a liquid matrix and a wide solidus-to-liquidus transition area. Currently, this process is industrially successful, generating a variety of products with high quality parts in various industrial sectors. Throughout the years since its inception, a number of technologies to produce the appropriate globular microstructure have been developed and applied worldwide. The main aim of this paper is to classify the presently available SSM technologies and present a comprehensive review of the potential mechanisms that lead to microstructural alterations during the preparation of feedstock materials for SSM processing.

MeSH terms: Computer Simulation; Hardness; Heating/methods*; Metallurgy/methods*; Models, Chemical*; Phase Transition
Fulltext Development of Chitosan Nanoparticles as a Stable Drug Delivery System for Protein/siRNA

Katas H, Raja MA, Lam KL

Int J Biomater, 2013;2013:146320.
PMID: 24194759 DOI: 10.1155/2013/146320

Chitosan nanoparticles (CS NPs) exhibit good physicochemical properties as drug delivery systems. The aim of this study is to determine the modulation of preparative parameters on the physical characteristics and colloidal stability of CS NPs. CS NPs were fabricated by ionic interaction with dextran sulphate (DS) prior to determination of their storage stability. The smallest CS NPs of 353 ± 23 nm with a surface charge of +56.2 ± 1.5 mV were produced when CS and DS were mixed at pH 4 and with a DS : CS mass ratio of 0.5 : 1. An entrapment efficiency of 98% was achieved when BSA/siRNA was loaded into the nanoparticles. The results also showed that particle size and surface charge of CS NPs were slightly changed up to 2 weeks when stored at 4°C. Greater particle size and surface charge were obtained with increasing the concentration of DS. In conclusion, NPs were sufficiently stable when kept at 4°C and able to carry and protect protein.
Fulltext The In Vitro Antibiotic Susceptibility of Malaysian Isolates of Burkholderia pseudomallei

Ahmad N, Hashim R, Mohd Noor A

Int J Microbiol, 2013;2013:121845.
PMID: 24194761 DOI: 10.1155/2013/121845

Acute melioidosis may present as localised or septicaemic infections and can be fatal if left untreated. Burkholderia pseudomallei resistant to antibiotics used for the treatment of melioidosis had been reported. The aim of this study was to determine the in vitro antibiotic susceptibility patterns of Burkholderia pseudomallei isolated in Malaysia to a panel of antibiotics used for the treatment of melioidosis and also to potential alternative antibiotics such as tigecycline, ampicillin/sulbactam, and piperacillin/tazobactam. A total of 170 Burkholderia pseudomallei isolates were subjected to minimum inhibitory concentration determination using E-test method to eleven antibiotics. All isolates were sensitive to meropenem and piperacillin/tazobactam. For ceftazidime, imipenem, amoxicillin/clavulanic acid, and doxycycline resistance was observed in 1 isolate (0.6%) for each of the antibiotics. Trimethoprim/sulfamethoxazole resistance was observed in 17 (10%) isolates. For other antibiotics, ampicillin/sulbactam, chloramphenicol, tigecycline, and ciprofloxacin resistance were observed in 1 (0.6%), 6 (3.5%), 60 (35.3%) and 98 (57.7%) isolates respectively. One isolate B170/06 exhibited resistance to 4 antibiotics, namely, ciprofloxacin, chloramphenicol, trimethoprim/sulfamethoxazole, and tigecycline. In conclusion, the Malaysian isolates were highly susceptible to the current antibiotics used in the treatment of melioidosis in Malaysia. Multiple resistances to the antibiotics used in the maintenance therapy are the cause for a concern.

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