Browse publications by year: 2013

  1. Lee JS, Ee ML, Chung KH, Othman Z
    Carbohydr Polym, 2013 Sep 12;97(2):614-7.
    PMID: 23911492 DOI: 10.1016/j.carbpol.2013.05.047
    The effect of gamma-irradiation on formation of resistant starch (RS) in corn starch with different amylose content was examined. Normal corn starch, waxy corn starch, and high amylose corn starch (Hylon V and Hylon VII) were irradiated at 5, 10, 25 and 50 kGy. Gamma-irradiation at 5 kGy increased the amylose-like molecules in starches and thus significantly enhanced the RS content (p<0.05). Highest RS content was produced by 50 kGy irradiated in all the starch samples (p<0.05). The irradiation-induced RS was more evident in waxy corn starch, followed by high amylose corn starch and normal corn starch.
    MeSH terms: Amylose/analysis; Zea mays/chemistry*; Dose-Response Relationship, Radiation; Gamma Rays*; Microscopy, Electron, Scanning; Starch/chemical synthesis*; Starch/radiation effects*
  2. Chow YH, Yap YJ, Anuar MS, Tejo BA, Ariff A, Show PL, et al.
    PMID: 23911538 DOI: 10.1016/j.jchromb.2013.06.034
    A relationship is proposed for the interfacial partitioning of protein in poly(ethylene glycol) (PEG)-phosphate aqueous two-phase system (ATPS). The relationship relates the natural logarithm of interfacial partition coefficient, ln G to the PEG concentration difference between the top and bottom phases, Δ[PEG], with the equation ln G=AΔ[PEG]+B. Results showed that this relationship provides good fits to the partition of bovine serum albumin (BSA) in ATPS which is comprised of phosphate and PEG of four different molecular weight 1450g/mol, 2000g/mol, 3350g/mol and 4000g/mol, with the tie-line length (TLL) in the range of 44-60% (w/w) at pH 7.0. The decrease of A values with the increase of PEG molecular weight indicates that the correlation between ln G and Δ[PEG] decreases with the increase in PEG molecular weight and the presence of protein-polymer hydrophobic interaction. When temperature was increased, a non-linear relationship of ln G inversely proportional to temperature was observed. The amount of proteins adsorbed at the interface increased proportionally with the amount of BSA loaded whereas the partition coefficient, K remained relatively constant. The relationship proposed could be applied to elucidate interfacial partitioning behaviour of other biomolecules in polymer-salt ATPS.
    MeSH terms: Adsorption; Hydrogen-Ion Concentration; Kinetics; Models, Theoretical; Molecular Weight; Polyethylene Glycols/chemistry*; Polymers/chemistry*; Salts; Serum Albumin, Bovine/isolation & purification; Serum Albumin, Bovine/chemistry*; Temperature; Solid Phase Extraction/instrumentation*; Hydrophobic and Hydrophilic Interactions
  3. Ali MM, Lim KS, Yang HZ, Chong WY, Lim WS, Ahmad H
    Appl Opt, 2013 Aug 1;52(22):5393-7.
    PMID: 23913056 DOI: 10.1364/AO.52.005393
    This paper proposes an approach based on an optical imaging technique for the period measurement of fiber Bragg gratings (FBG). The simple, direct technique involves a differential interface contrast (DIC) microscope and a high-resolution CCD camera. Image processing is performed on the microscope images to obtain low-noise grating profiles and then the grating periods. Adopting a large image sample size in the image processing can reduce uncertainty. During the investigation, FBGs of different grating periods are fabricated by prestraining the photosensitive fibers during the UV-writing process. A good linearity between the measured Bragg wavelengths and grating periods is observed and the measured strain-optics coefficient was found to be in agreement with reported literature.
    MeSH terms: Photosensitivity Disorders; Writing; Dermatitis, Phototoxic; Sample Size; Uncertainty; Optics and Photonics; Optical Imaging
  4. Mihailidis S, Scriven G, Khamis M, Townsend G
    Am J Phys Anthropol, 2013 Sep;152(1):19-30.
    PMID: 23913636 DOI: 10.1002/ajpa.22323
    We present new data on the prevalence and patterning of the maxillary premolar accessory ridge (MxPAR), a common but understudied morphological dental trait that is expressed as a linear elevation extending from the buccal cusp ridge to the medial sulcus of maxillary premolar teeth. A total of 579 sets of dental casts, representing six ethnic groups, were scored using the five-grade system proposed by Burnett et al. (2010). The frequency and distribution of the MxPAR were determined by tooth type, sex, side, locus and ethnicity, and the applicability of the scoring system was assessed. The MxPAR was found in approximately two-thirds of premolar teeth, more often on second than first premolars, and more often on the distal aspect of the occlusal surface than the mesial. There was some evidence that more pronounced forms of the feature occurred more often in males than females, and that there may be some directionality in its expression between sides. Variation was also noted in the frequency of occurrence and degree of expression of the MxPAR between ethnic groups. Intra- and inter-observer concordance rates for scoring the MxPAR were low, confirming that it was difficult to score the trait identically on two different occasions. Our findings have clarified the distribution of the MxPAR within the dentition and between ethnic groups, and highlighted the need for researchers to carry out thorough replicability studies and to decide on an appropriate breakpoint for determining presence or absence of this feature before embarking on genetic studies or bio-distance analyses.
    MeSH terms: Adolescent; Adult; Anthropology, Physical; Australia; Bicuspid/anatomy & histology*; Ethnic Groups/statistics & numerical data; Female; Humans; Malaysia; Male; Sex Characteristics; Chi-Square Distribution; Tooth Crown/anatomy & histology*; European Continental Ancestry Group/statistics & numerical data*
  5. Budin SB, Han KJ, Jayusman PA, Taib IS, Ghazali AR, Mohamed J
    J Toxicol Pathol, 2013 Jun;26(2):111-8.
    PMID: 23914053 DOI: 10.1293/tox.26.111
    Fenitrothion (FNT) is an organophosphate compound widely used as pesticide in Malaysia. The present study aims to investigate effects of palm oil tocotrienol rich fraction (TRF) on the renal damage of FNT-treated rats. A total of 40 male Sprague Dawley rats were divided into 4 groups randomly, the control, TRF, FNT and FNT+TRF groups. FNT (20 mg/kg b.w.) and TRF (200 mg/kg b.w.) were given orally for 28 days continuously. Rats from the FNT+TRF group were supplemented with TRF 30 minutes prior to administration of FNT. Rats were sacrificed after 28 days, and the kidneys were removed for determination of oxidative stress and histological analysis. Plasma was collected for determination of blood creatinine and urea level. Statistical analysis showed that palm oil TRF has a protective effect against renal oxidative damage induced by FNT. In the FNT+TRF group, malondialdehyde and protein carbonyl levels were significantly lower, while the glutathione level as well as superoxide dismutase and catalase activities were significantly higher compared with the FNT-treated group (p<0.05). As for renal function, there was a markedly lower urea level (p<0.05) in the FNT+TRF group compared with the FNT-treated group, but there was no significant difference in creatinine level. Besides, total protein also showed no significant difference for all groups of rats (p>0.05). Histological evaluation also revealed that the FNT+TRF group had less glomerulus and renal tubule damage than the FNT-treated group. In conclusion, palm oil TRF was able to reduce oxidative stress and renal damage in FNT-treated rats.
  6. Geok CK, Abdullah KL, Kee LH
    Int J Nurs Pract, 2013 Aug;19(4):381-9.
    PMID: 23915407 DOI: 10.1111/ijn.12083
    The purpose of this paper is to examine the quality of life (QOL) among mothers with a child with Down syndrome using The World Health Organization Quality of Life scale instrument. A convenience sample of 161 mothers was accessed through the various institutions which provide interventional or educational programmes to children with disabilities within two of the regions of the Borneo State of Malaysia (Sarawak). Nearly half of the group of mothers perceived their QOL as neither poor nor good (n = 73). An overall QOL score of 14.0 ± 1.84 was obtained. The highest and lowest domain scores were found for social relationship domain (Mean = 14.9 ± 2.1) and environmental support domain (Mean = 13.3 ± 2.1) respectively. Correlation analysis of selected background variables (i.e. locality, education, income and marital status) and overall QOL indicated rho (161) = 0.22-0.28 (P < 0.01). Inverse correlation between maternal age and overall QOL score was indicated, with rho (161) = -0.17 (P < 0.05). Linear regression analysis indicated that the combination of these few variables together accounted for 14.5% of the QOL variability in the sample. Findings point to implications for priorities of care provisions by policy-makers and care professionals in their practice.
    MeSH terms: Adult; Child; Down Syndrome/psychology*; Female; Humans; Malaysia; Middle Aged; Mothers/psychology*; Quality of Life*
  7. Nordin MA, Wan Harun WH, Abdul Razak F
    Arch Oral Biol, 2013 Oct;58(10):1335-42.
    PMID: 23915676 DOI: 10.1016/j.archoralbio.2013.07.001
    The adherence of Candida to mucosal surfaces is the initial step for successful invasive process of the oral cavity. The study aimed to investigate the effect of two plant extracts on the non-specific and specific bindings of oral candida.
    MeSH terms: Adsorption; Candida/drug effects*; Cell Adhesion/drug effects*; Humans; Plant Extracts/pharmacology*; Saliva; Piper betle*; Brucea*; Dental Pellicle/microbiology; In Vitro Techniques
  8. Chiang PP, Lamoureux EL, Shankar A, Tai ES, Wong TY, Sabanayagam C
    BMC Public Health, 2013;13:730.
    PMID: 23919264 DOI: 10.1186/1471-2458-13-730
    BACKGROUND: Prehypertension has been shown to be an early risk factor of cardiovascular disease (CVD). We investigated the prevalence and pattern of cardiometabolic risk factors in prehypertension in three ethnic Asian populations in Singapore.
    METHODS: We examined data from Chinese (n=1177), Malay (n=774), and Indian (n=985) adults aged 40-80 years who participated in three independent population based studies conducted from 2004-2011 in Singapore who were free of diabetes, hypertension and previous CVD. Prehypertension was defined as systolic blood pressure (BP) 120-139 mm Hg or diastolic BP 80-89 mm Hg. Random blood glucose, glycated haemoglobin (HbA1c), body mass index (BMI), triglycerides, low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol were examined as indicators of adverse cardiometabolic profile. The association between metabolic variables and prehypertension was examined using logistic regression models adjusting for potential confounders.
    RESULTS: The prevalence of prehypertension was 59.8% (Chinese), 68.9% (Malays) and 57.7% Indians. Higher levels of blood glucose, HbA1c and BMI were significantly associated with prehypertension in all three ethnic groups, odds ratio (95% confidence interval) of prehypertension in Chinese, Malays and Indians were: 1.42 (1.10, 1.83), 1.53 (1.05, 2.24), 1.49 (1.13, 1.98) for high-glucose; 3.50 (1.01, 12.18), 3.72 (1.29, 10.75), 2.79 (1.31, 5.94) for high-HbA1c; 1.86 (1.34, 2.56), 2.96 (2.10, 4.18), 1.68 (1.28, 2.20) for high-BMI. In addition, higher levels of LDL cholesterol in Chinese and higher levels of triglycerides were significantly associated with prehypertension. These associations persisted when metabolic variables were analysed as continuous variables.
    CONCLUSIONS: Higher levels of blood glucose, HbA1c and BMI were associated with prehypertension in all three ethnic groups in Singapore. Screening for prehypertension and lifestyle modifications could potentially reduce the burden of CVD in otherwise healthy Asian adults living in Singapore.
    MeSH terms: Adult; Aged; Aged, 80 and over; Blood Glucose/analysis; Blood Pressure; China/ethnology; Ethnic Groups; Female; Hemoglobin A, Glycosylated/analysis; Humans; India/ethnology; Life Style; Cholesterol, HDL/blood; Cholesterol, LDL/blood; Malaysia/ethnology; Male; Middle Aged; Risk Factors; Singapore; Singapore/epidemiology; Triglycerides/blood; Body Mass Index; Prevalence; Logistic Models; Odds Ratio; Prehypertension/blood*; Prehypertension/ethnology; Prehypertension/epidemiology*
  9. Ramimoghadam D, Bin Hussein MZ, Taufiq-Yap YH
    Chem Cent J, 2013;7:136.
    PMID: 23919386 DOI: 10.1186/1752-153X-7-136
    BACKGROUND: Rice as a renewable, abundant bio-resource with unique characteristics can be used as a bio-template to synthesize various functional nanomaterials. Therefore, the effect of uncooked rice flour as bio-template on physico-chemical properties, especially the morphology of zinc oxide nanostructures was investigated in this study. The ZnO particles were synthesized through hydrothermal-biotemplate method using zinc acetate-sodium hydroxide and uncooked rice flour at various ratios as precursors at 120°C for 18 hours.

    RESULTS: The results indicate that rice as a bio-template can be used to modify the shape and size of zinc oxide particles. Different morphologies, namely flake-, flower-, rose-, star- and rod-like structures were obtained with particle size at micro- and nanometer range. Pore size and texture of the resulting zinc oxide particles were found to be template-dependent and the resulting specific surface area enhanced compared to the zinc oxide synthesized without rice under the same conditions. However, optical property particularly the band gap energy is generally quite similar.

    CONCLUSION: Pure zinc oxide crystals were successfully synthesized using rice flour as biotemplate at various ratios of zinc salt to rice. The size- and shape-controlled capability of rice to assemble the ZnO particles can be employed for further useful practical applications.

  10. Alosfur FK, Jumali MH, Radiman S, Ridha NJ, Yarmo MA, Umar AA
    Nanoscale Res Lett, 2013;8(1):346.
    PMID: 23919496 DOI: 10.1186/1556-276X-8-346
    Recently, TiO2/multi-walled carbon nanotube (MWCNT) hybrid nanocatalysts have been a subject of high interest due to their excellent structures, large surface areas and peculiar optical properties, which enhance their photocatalytic performance. In this work, a modified microwave technique was used to rapidly synthesise a TiO2/MWCNT nanocatalyst with a large surface area. X-ray powder diffraction, field-emission scanning electron microscopy, transmission electron microscopy and Brunauer-Emmett-Teller measurements were used to characterise the structure, morphology and the surface area of the sample. The photocatalytic activity of the hybrid nanocatalysts was evaluated through a comparison of the degradation of methylene blue dye under irradiation with ultraviolet and visible light. The results showed that the TiO2/MWCNT hybrid nanocatalysts degraded 34.9% of the methylene blue (MB) under irradiation with ultraviolet light, whereas 96.3% of the MB was degraded under irradiation with visible light.
    MeSH terms: Light; Methylene Blue; Microscopy, Electron, Scanning; Microwaves; Titanium; Ultraviolet Rays; X-Ray Diffraction; X-Rays; Powder Diffraction; Nanotubes, Carbon; Microscopy, Electron, Transmission
  11. Nor Azlin MI, Abd Rahman R, Abdul Karim AK, Sulaiman AS, Mahdy ZA
    J Obstet Gynaecol, 2013 Aug;33(6):631-2.
    PMID: 23919870 DOI: 10.3109/01443615.2013.807781
    MeSH terms: Adult; Female; Humans; Pregnancy; Pregnancy Complications*; Pregnancy Outcome; Spinal Cord Injuries*
  12. Epifano F, Fiorito S, Genovese S
    Phytochemistry, 2013 Nov;95:12-8.
    PMID: 23920228 DOI: 10.1016/j.phytochem.2013.07.013
    The genus Acronychia (Rutaceae) comprise 44 species, most of which are represented by shrubs and small trees, distributed in a wide geographical area of South-Eastern Asia comprising China, India, Malaysia, Indonesia, Australia, and the islands of the western Pacific Ocean. Most of the species of the genus Acronychia have been used for centuries as natural remedies in the ethnomedical traditions of indigenous populations as anti-microbial, anti-fungal, anti-spasmodic, stomachic, anti-pyretic, and anti-haemorragic agent. Moreover fruits and aerial parts are used as food in salads and condiments, while the essential oil obtained from flowers and leaves has been employed in cosmetics production. Phytochemicals isolated from Acronychia spp. include acetophenones, quinoline and acridone alkaloids, flavonoids, cinnamic acids, lignans, coumarins, steroids, and triterpenes. The reported biological activities of the above mentioned natural compounds refer to anti-plasmodial, anti-cancer, anti-oxidant, anti-inflammatory, anti-fungal, and neuroprotective effects. The aim of this review is to examine in detail from a phytochemical and pharmacologically point of view what is reported in the current literature about the properties of phytopreparations or individual active principles obtained from plants belonging to the Acronychia genus.
    MeSH terms: Animals; Humans; Phytotherapy*; Medicine, Traditional; Pharmacognosy; Plant Extracts/pharmacology*; Plant Extracts/therapeutic use; Rutaceae/chemistry*; Phytochemicals/pharmacology*; Phytochemicals/therapeutic use
  13. Lee ST, Wong PF, Hooper JD, Mustafa MR
    Phytomedicine, 2013 Nov 15;20(14):1297-305.
    PMID: 23920276 DOI: 10.1016/j.phymed.2013.07.002
    Alpha (α)-tomatine, a major saponin found in tomato has been shown to inhibit the growth of androgen-independent prostate cancer PC-3 cells. The effects of α-tomatine in combination with the chemotherapeutic agent paclitaxel against PC-3 cells were investigated in the present study. Combined treatment with a sub-toxic dose of α-tomatine and paclitaxel significantly decreased cell viability with concomitant increase in the percentage of apoptotic PC-3 cells. The combined treatment, however, had no cytotoxic effect on the non-neoplastic prostate RWPE-1 cells. Apoptosis of PC-3 cells was accompanied by the inhibition of PI3K/Akt pro-survival signaling, an increase in the expression of the pro-apoptotic protein BAD but a decrease in the expressions of anti-apoptotic proteins, Bcl-2 and Bcl-xL. Results from a mouse xenograft model showed the combined treatment completely suppressed subcutaneous tumor growth without significant side effects. Consistent with its in vitro anti-cancer effects, tumor materials from mice showed increased apoptosis of tumor cells with reduced protein expression of activated PI3K/Akt. These results suggest that the synergistic anti-cancer effects of paclitaxel and α-tomatine may be beneficial for refractory prostate cancer treatment.
    MeSH terms: Androgens/metabolism; Animals; Antineoplastic Agents, Phytogenic/pharmacology; Antineoplastic Agents, Phytogenic/therapeutic use*; Drug Synergism; Drug Therapy, Combination; Humans; Male; Phytotherapy*; Mice, Inbred BALB C; Mice, Nude; Plant Extracts/pharmacology; Plant Extracts/therapeutic use; Prostate/drug effects; Prostatic Neoplasms/drug therapy*; Prostatic Neoplasms/metabolism; Tomatine/analogs & derivatives*; Tomatine/pharmacology; Tomatine/therapeutic use; Signal Transduction; Apoptosis/drug effects*; Paclitaxel/pharmacology; Paclitaxel/therapeutic use*; Lycopersicon esculentum/chemistry*; Proto-Oncogene Proteins c-bcl-2/metabolism; Phosphatidylinositol 3-Kinases/metabolism; Cell Line, Tumor; bcl-Associated Death Protein/metabolism; bcl-2-Associated X Protein/metabolism; Proto-Oncogene Proteins c-akt/metabolism; Mice
  14. Kalong NA, Yusof MM
    Stud Health Technol Inform, 2013;192:749-53.
    PMID: 23920657
    Despite the rapid application of the Lean method in healthcare, its study in IT environments, particularly in Health Information Systems (HIS), is still limited primarily by a lack of waste identification. This paper aims to review the literature to provide an insight into the nature of waste in HIS from the perspective of Lean management. Eight waste frameworks within the context of healthcare and information technology were reviewed. Based on the review, it was found that all the seven waste categories from the manufacturing sector also exist in both the healthcare and IT domains. However, the nature of the waste varied depending on the processes of the domains. A number of additional waste categories were also identified. The findings reveal that the traditional waste model can be adapted to identify waste in both the healthcare and IT sectors.
    MeSH terms: Pilot Projects; Cost Savings/economics*; Cost Savings/methods*; Health Care Costs/statistics & numerical data*; Models, Economic*; Internationality; Health Information Systems/economics*
  15. Liew HJ, Chiarella D, Pelle A, Faggio C, Blust R, De Boeck G
    PMID: 23921225 DOI: 10.1016/j.cbpa.2013.07.029
    The objective of this study was to investigate the interaction between feeding, exercise and cortisol on metabolic strategies of common carp over a 168h post-implant period. Feeding provided readily available energy and clearly increased muscle and liver protein and glycogen stores. Swimming, feeding and cortisol all induced aerobic metabolism by increasing oxygen consumption, and stimulated protein metabolism as demonstrated by the increased ammonia and urea excretion and ammonia quotient. Hypercortisol stimulated ammonia self-detoxifying mechanisms by enhancing ammonia and urea excretion, especially during severe exercise. At high swimming level, higher branchial clearance rates in cortisol treated fish succeeded in eliminating the elevation of endogenous ammonia, resulting in reduced plasma Tamm levels compared to control and sham implanted fish. Carp easily induced anaerobic metabolism, both during routine and active swimming, with elevated lactate levels as a consequence. Both feeding and cortisol treatment increased this dependence on anaerobic metabolism. Hypercortisol induced both glycogenesis and gluconeogenesis resulting in hyperglycemia and muscle and liver glycogen deposition, most likely as a protective mechanism for prolonged stress situations and primarily fuelled by protein mobilization.
    MeSH terms: Ammonia/blood; Ammonia/urine; Animals; Blood Glucose; Carps/metabolism*; Energy Metabolism*; Feeding Behavior; Glycogen/metabolism; Hydrocortisone/blood*; Hydrocortisone/physiology; Liver/metabolism; Oxygen Consumption*; Stress, Physiological; Swimming; Urea/blood; Urea/urine; Muscle, Skeletal/metabolism; Lactic Acid/blood; Fish Proteins/metabolism; Lipid Metabolism
  16. Martin A, Moore C, Mallon PW, Hoy J, Emery S, Belloso W, et al.
    AIDS, 2013 Sep 24;27(15):2403-11.
    PMID: 23921615 DOI: 10.1097/01.aids.0000432534.47217.b4
    To compare changes over 48 weeks in bone mineral density (BMD) between participants randomized to lopinavir/ritonavir (LPV/r) + raltegravir (RAL) or LPV/r + 2-3 nucleoside/nucleotide reverse transcriptase inhibitors (N(t)RTIs) as second line therapy.
    MeSH terms: Raltegravir Potassium; Adult; Argentina/epidemiology; Bone Diseases, Metabolic/complications; Bone Diseases, Metabolic/epidemiology*; Female; Femur/radiography; Humans; India/epidemiology; Lumbar Vertebrae/radiography; Malaysia/epidemiology; Male; Osteoporosis/complications; Osteoporosis/epidemiology*; Pyrrolidinones/adverse effects; Risk Factors; South Africa/epidemiology; Thailand/epidemiology; Absorptiometry, Photon; Bone Density/drug effects*; HIV Infections/complications; HIV Infections/drug therapy*; Prevalence; Treatment Outcome; HIV Protease Inhibitors/administration & dosage; HIV Protease Inhibitors/adverse effects*; Reverse Transcriptase Inhibitors/administration & dosage; Reverse Transcriptase Inhibitors/adverse effects*; Ritonavir/adverse effects; Lopinavir/adverse effects
  17. Suriani NS, Hussain A, Zulkifley MA
    Sensors (Basel), 2013 Aug 05;13(8):9966-98.
    PMID: 23921828 DOI: 10.3390/s130809966
    Event recognition is one of the most active research areas in video surveillance fields. Advancement in event recognition systems mainly aims to provide convenience, safety and an efficient lifestyle for humanity. A precise, accurate and robust approach is necessary to enable event recognition systems to respond to sudden changes in various uncontrolled environments, such as the case of an emergency, physical threat and a fire or bomb alert. The performance of sudden event recognition systems depends heavily on the accuracy of low level processing, like detection, recognition, tracking and machine learning algorithms. This survey aims to detect and characterize a sudden event, which is a subset of an abnormal event in several video surveillance applications. This paper discusses the following in detail: (1) the importance of a sudden event over a general anomalous event; (2) frameworks used in sudden event recognition; (3) the requirements and comparative studies of a sudden event recognition system and (4) various decision-making approaches for sudden event recognition. The advantages and drawbacks of using 3D images from multiple cameras for real-time application are also discussed. The paper concludes with suggestions for future research directions in sudden event recognition.
    MeSH terms: Algorithms*; Artificial Intelligence*; Image Interpretation, Computer-Assisted/methods*; Pattern Recognition, Automated/methods*; Photography/methods*; Video Recording/methods*
  18. Mohammad R, Ahmad M, Heng LY
    Sensors (Basel), 2013 Aug 05;13(8):10014-26.
    PMID: 23921830 DOI: 10.3390/s130810014
    Chili hotness is very much dependent on the concentration of capsaicin present in the chili fruit. A new biosensor based on a horseradish peroxidase enzyme-capsaicin reaction mediated by ferrocene has been successfully developed for the amperometric determination of chili hotness. The amperometric biosensor is fabricated based on a single-step immobilization of both ferrocene and horseradish peroxidase in a photocurable hydrogel membrane, poly(2-hydroxyethyl methacrylate). With mediation by ferrocene, the biosensor could measure capsaicin concentrations at a potential 0.22 V (vs. Ag/AgCl), which prevented potential interference from other electroactive species in the sample. Thus a good selectivity towards capsaicin was demonstrated. The linear response range of the biosensor towards capsaicin was from 2.5-99.0 µM with detection limit of 1.94 µM. A good relative standard deviation (RSD) for reproducibility of 6.4%-9.9% was obtained. The capsaicin biosensor demonstrated long-term stability for up to seven months. The performance of the biosensor has been validated using a standard method for the analysis of capsaicin based on HPLC.
    MeSH terms: Capsaicin/analysis*; Capsaicin/chemistry*; Conductometry/instrumentation*; Electrodes; Equipment Design; Ferrous Compounds/chemistry*; Horseradish Peroxidase/chemistry*; Humans; Taste*; Biosensing Techniques/instrumentation*; Equipment Failure Analysis
  19. Oshkour AA, Abu Osman NA, Davoodi MM, Yau YH, Tarlochan F, Wan Abas WA, et al.
    Int J Numer Method Biomed Eng, 2013 Dec;29(12):1412-27.
    PMID: 23922316 DOI: 10.1002/cnm.2583
    This study focused on developing a 3D finite element model of functionally graded femoral prostheses to decrease stress shielding and to improve total hip replacement performance. The mechanical properties of the modeled functionally graded femoral prostheses were adjusted in the sagittal and transverse planes by changing the volume fraction gradient exponent. Prostheses with material changes in the sagittal and transverse planes were considered longitudinal and radial prostheses, respectively. The effects of cemented and noncemented implantation methods were also considered in this study. Strain energy and von Mises stresses were determined at the femoral proximal metaphysis and interfaces of the implanted femur components, respectively. Results demonstrated that the strain energy increased proportionally with increasing volume fraction gradient exponent, whereas the interface stresses decreased on the prostheses surfaces. A limited increase was also observed at the surfaces of the bone and cement. The periprosthetic femur with a noncemented prosthesis exhibited higher strain energy than with a cemented prosthesis. Radial prostheses implantation displayed more strain energy than longitudinal prostheses implantation in the femoral proximal part. Functionally graded materials also increased strain energy and exhibited promising potentials as substitutes of conventional materials to decrease stress shielding and to enhance total hip replacement lifespan.
    MeSH terms: Hip Prosthesis*; Materials Testing; Prosthesis Design; Stress, Mechanical*; Finite Element Analysis*
  20. Christina A, Christapher V, Bhore SJ
    Pharmacogn Rev, 2013 Jan;7(13):11-6.
    PMID: 23922451 DOI: 10.4103/0973-7847.112833
    World human population is increasing with an alarming rate; and a variety of new types of health issues are popping up. For instance, increase in number of drug-resistant bacteria is a cause of concern. Research on antibiotics and other microbial natural products is pivotal in the global fight against the growing problem of antibiotic resistance. It is necessary to find new antibiotics to tackle this problem. The use of therapeutic plant species in traditional medicine is as old as mankind; and currently, it is strongly believed that all types of plant species across the plant kingdom do harbour endophytic bacteria (EB). The natural therapeutic compounds produced by EB do have several potential applications in pharmaceutical industry. The EB derived natural products such as Ecomycins, Pseudomycins, Munumbicins and Xiamycins are antibacterial, antimycotic and antiplasmodial. Some of these natural products have been reported to possess even antiviral (including Human Immunodeficiency Virus (HIV)) properties. Therefore, to deal with increasing number of drug-resistant pathogens EB could serve as a potential source of novel antibiotics.
    MeSH terms: Anti-Bacterial Agents; Antimalarials; Antiviral Agents; Bacteria; Biological Products; Drug Industry; Drug Resistance, Microbial; Humans; Medicine, Traditional; HIV Infections
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