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  1. Fulltext Isolation, Characterization and Neuroprotective Activity of Folecitin: An In Vivo Study
    Farooq U, Khan T, Shah SA, Hossain MS, Ali Y, Ullah R, et al.
    Life (Basel), 2021 Aug 12;11(8).
    PMID: 34440569 DOI: 10.3390/life11080825
    Neurodegenerative diseases (NDs) extend the global health burden. Consumption of alcohol as well as maternal exposure to ethanol can damage several neuronal functions and cause cognition and behavioral abnormalities. Ethanol induces oxidative stress that is linked to the development of NDs. Treatment options for NDs are yet scarce, and natural product-based treatments could facilitate ND management since plants possess plenty of bioactive metabolites, including flavonoids, which typically demonstrate antioxidant and anti-inflammatory properties. Hypericum oblongifolium is an important traditional medicinal plant used for hepatitis, gastric ulcer, external wounds, and other gastrointestinal disorders. However, it also possesses multiple bioactive compounds and antioxidant properties, but the evaluation of isolated pure compounds for neuroprotective efficacy has not been done yet. Therefore, in the current study, we aim to isolate and characterize the bioactive flavonoid folecitin and evaluate its neuroprotective activity against ethanol-induced oxidative-stress-mediated neurodegeneration in the hippocampus of postnatal day 7 (PND-7) rat pups. A single dose of ethanol (5 g/kg body weight) was intraperitoneally administered after the birth of rat pups on PND-7. This caused oxidative stress accompanied by the activation of phosphorylated-c-Jun N-terminal kinase (p-JNK), nod-like receptor family pyrin domain containing 3 (NLRP3), apoptosis-associated speck-like protein (ASC), and cysteine-aspartic acid protease-1 (caspase-1) proteins to form a complex called the NLRP3-inflammasome, which converts pro-interleukin 1 beta (IL-1B) to activate IL-1B and induce widespread neuroinflammation and neurodegeneration. In contrast, co-administration of folecitin (30 mg/kg body weight) reduced ethanol-induced oxidative stress, inhibited p-JNK, and deactivated the NLRP3-inflammasome complex. Furthermore, folecitin administration reduced neuroinflammatory and neurodegenerative protein markers, including decreased caspase-3, BCL-2-associated X protein (BAX), B cell CLL/lymphoma 2 (BCL-2), and poly (ADP-ribose) polymerase-1 (PARP-1) expression in the immature rat brain. These findings conclude that folecitin is a flavone compound, and it might be a novel, natural and safe agent to curb oxidative stress and its downstream harmful effects, including inflammasome activation, neuroinflammation, and neurodegeneration. Further evaluation in a dose-dependent manner would be worth it in order to find a suitable dose regimen for NDs.
  2. Fulltext Recent Advances in the Biosynthesis of Polyhydroxyalkanoates from Lignocellulosic Feedstocks
    Vigneswari S, Noor MSM, Amelia TSM, Balakrishnan K, Adnan A, Bhubalan K, et al.
    Life (Basel), 2021 Aug 10;11(8).
    PMID: 34440551 DOI: 10.3390/life11080807
    Polyhydroxyalkanoates (PHA) are biodegradable polymers that are considered able to replace synthetic plastic because their biochemical characteristics are in some cases the same as other biodegradable polymers. However, due to the disadvantages of costly and non-renewable carbon sources, the production of PHA has been lower in the industrial sector against conventional plastics. At the same time, first-generation sugar-based cultivated feedstocks as substrates for PHA production threatens food security and considerably require other resources such as land and energy. Therefore, attempts have been made in pursuit of suitable sustainable and affordable sources of carbon to reduce production costs. Thus, in this review, we highlight utilising waste lignocellulosic feedstocks (LF) as a renewable and inexpensive carbon source to produce PHA. These waste feedstocks, second-generation plant lignocellulosic biomass, such as maize stoves, dedicated energy crops, rice straws, wood chips, are commonly available renewable biomass sources with a steady supply of about 150 billion tonnes per year of global yield. The generation of PHA from lignocellulose is still in its infancy, hence more screening of lignocellulosic materials and improvements in downstream processing and substrate pre-treatment are needed in the future to further advance the biopolymer sector.
  3. Fulltext A Review on Impedimetric and Voltammetric Analysis Based on Polypyrrole Conducting Polymers for Electrochemical Sensing Applications
    Dzulkurnain NA, Mokhtar M, Rashid JIA, Knight VF, Wan Yunus WMZ, Ong KK, et al.
    Polymers (Basel), 2021 Aug 15;13(16).
    PMID: 34451266 DOI: 10.3390/polym13162728
    Conducting polymers have been widely used in electrochemical sensors as receptors of the sensing signal's analytes and transducers. Polypyrrole (PPy) conducting polymers are highlighted due to their good electrical conductive properties, ease in preparation, and flexibility of surface characteristics. The objective of this review paper is to discuss the theoretical background of the two main types of electrochemical detection: impedimetric and voltammetric analysis. It also reviews the application and results obtained from these two electrochemical detections when utilizing PPy as a based sensing material in electrochemical sensor. Finally, related aspects in electrochemical sensor construction using PPy will also be discussed. It is anticipated that this review will provide researchers, especially those without an electrochemical analysis background, with an easy-to-understand summary of the concepts and technologies used in electrochemical sensor research, particularly those interested in utilizing PPy as a based sensing material.
  4. Fulltext Synthesis and Characterization of Gefitinib and Paclitaxel Mono and Dual Drug-Loaded Blood Cockle Shells (Anadara granosa)-Derived Aragonite CaCO3 Nanoparticles
    Chemmalar S, Intan-Shameha AR, Abdullah CAC, Ab Razak NA, Yusof LM, Ajat M, et al.
    Nanomaterials (Basel), 2021 Aug 02;11(8).
    PMID: 34443820 DOI: 10.3390/nano11081988
    Calcium carbonate has slowly paved its way into the field of nanomaterial research due to its inherent properties: biocompatibility, pH-sensitivity, and slow biodegradability. In our efforts to synthesize calcium carbonate nanoparticles (CSCaCO3NP) from blood cockle shells (Anadara granosa), we developed a simple method to synthesize CSCaCO3NP, and loaded them with gefitinib (GEF) and paclitaxel (PTXL) to produce mono drug-loaded GEF-CSCaCO3NP, PTXL-CSCaCO3NP, and dual drug-loaded GEF-PTXL-CSCaCO3NP without usage of toxic chemicals. Fourier-transform infrared spectroscopy (FTIR) results reveal that the drugs are bound to CSCaCO3NP. Scanning electron microscopy studies reveal that the CSCaCO3NP, GEF-CSCaCO3NP, PTXL-CSCaCO3NP, and GEF-PTXL-CSCaCO3NP are almost spherical nanoparticles, with a diameter of 63.9 ± 22.3, 83.9 ± 28.2, 78.2 ± 26.4, and 87.2 ± 26.7 (nm), respectively. Dynamic light scattering (DLS) and N2 adsorption-desorption experiments revealed that the synthesized nanoparticles are negatively charged and mesoporous, with surface areas ranging from ~8 to 10 (m2/g). Powder X-ray diffraction (PXRD) confirms that the synthesized nanoparticles are aragonite. The CSCaCO3NP show excellent alkalinization property in plasma simulating conditions and greater solubility in a moderately acidic pH medium. The release of drugs from the nanoparticles showed zero order kinetics with a slow and sustained release. Therefore, the physico-chemical characteristics and in vitro findings suggest that the drug loaded CSCaCO3NP represent a promising drug delivery system to deliver GEF and PTXL against breast cancer.
  5. Fulltext Awareness of cervical cancer among women in Malaysia
    Seng LM, Rosman AN, Khan A, Haris NM, Mustapha NAS, Husaini NSM, et al.
    Int J Health Sci (Qassim), 2018 7 20;12(4):42-48.
    PMID: 30022903
    Objectives: The purpose of this study is to evaluate and ascertain the current knowledge, perception, level of awareness, and attitudes toward cervical cancer (CC) among women in Malaysia.

    Methods: A cross-sectional study was conducted which involved 210 women aged between 21 and 60 years old at the public in Malaysia, a subsequent statistical analysis was performed by SPSS version 22.

    Results: In comparison with other studies, there is still lacking of awareness on CC and these induced informal cluelessness and poor attitudes toward it. In terms of risk factors, there are two factors with some degree of awareness among women in Malaysia, i.e., multiple sexual partners and sexually transmitted diseases. Women in Malaysia have less awareness on the causes and clinical manifestations of the disease (P < 0.05). They are aware that regular papanicolaou (Pap) smear would screen CC and surgery could be a treatment of choice. In addition, women in Malaysia also have moderate awareness about Pap smear as prevention to detect and prevent CC at the early stage.

    Conclusions: Women in Malaysia only has a good awareness about multiple sex partner and sexually transmitted disease as a risk factor for CC, they also have good knowledge on regular Pap smear as a tool to diagnose and surgery as a treatment. Future, further effort is required to promote awareness of women's perception and attitudes toward CC.
  6. Non-obstructive monitoring of muscle fatigue for low intensity dynamic exercise with infrared thermography technique
    Shakhih MFM, Ridzuan N, Wahab AA, Zainuddin NF, Delestri LFU, Rosslan AS, et al.
    Med Biol Eng Comput, 2021 Aug;59(7-8):1447-1459.
    PMID: 34156602 DOI: 10.1007/s11517-021-02387-x
    Surface electromyography (sEMG) has been widely used in evaluating muscle fatigue among athletes where electrodes are attached on the skin during the activity. Recently, infrared thermography technique (IRT) has gain popularity and shown to be another preferred method in monitoring and predicting muscle fatigue non-obstructively. This paper investigates the correlation between surface temperature and muscle activation parameters obtained using both IRT and sEMG methods simultaneously. Twenty healthy subjects were required to perform a repetitive calf raise exercise with various loads attached around their ankle for 3 min to induce fatigue on the targeted gastrocnemius muscles. Average temperature and temperature difference information were extracted from thermal images, while root mean square (RMS) and median frequency (MF) were extracted from sEMG signals. Spearman statistical analysis performed shows that there is a significant correlation between average temperature with RMS and between temperature difference with MF values at p<0.05. While ANOVA test conducted shows that there is significant impact of loads on RMS and MF where F=12.61 and 3.59, respectively, at p< 0.05. This study suggested that skin surface temperature can be utilized in monitoring and predicting muscle fatigue in low intensity dynamic exercise and can be extended to other dynamic exercises.
  7. Fulltext Effects of alternate nostril breathing exercise on cardiorespiratory functions in healthy young adults
    Jahan I, Begum M, Akhter S, Islam MZ, Jahan N, Samad N, et al.
    Ann Afr Med, 2021 7 3;20(2):69-77.
    PMID: 34213471 DOI: 10.4103/aam.aam_114_20
    Introduction: Alternate nostril breathing (ANB) is an effective breathing exercise with therapeutic benefits on cardiorespiratory functions for healthy and diseased individuals. This study was conducted to assess the effects of ANB exercise on cardiorespiratory tasks in healthy adults.

    Materials and Methods: This randomized experimental study was conducted in the Department of Physiology, Chittagong Medical College, Chattogram, from July 2017 to June 2018. A total of 100 1st-year students, aged between 18 and 20 years, were included by a random sampling method. Fifty participants (25 males and 25 females) were enrolled in the experimental group, while age- and body mass index-matched another 50 participants (25 males and 25 females) served as the control group. Experimental group participants performed ANB exercise for 4 weeks. Cardiorespiratory parameters (pulse rate, blood pressure, forced vital capacity, forced expiratory volume in 1st s [FEV1], and peak expiratory flow rate [PEFR] were measured. Data were taken at the start and after 4 weeks in both groups.

    Results: Independent t-test showed no significant differences in the cardiorespiratory functions between the experimental and control groups among the male and female participants, except for the females' PEFR which showed small differences. On the other hand, repeated measure ANOVA shows significant improvement in the experimental groups among males (P < 0.001-0.028) and females (P < 0.001-0.001) in all the cardiorespiratory functions measured, except for the FEV1 and PEFR among males.

    Conclusion: The results of this study suggest that cardiorespiratory functions were improved after breathing exercise, and therefore, ANB can be recommended for increasing cardiorespiratory efficiency.

  8. Fulltext Levels and health risk assessment of heavy metals in dried fish consumed in Bangladesh
    Rakib MRJ, Jolly YN, Enyoh CE, Khandaker MU, Hossain MB, Akther S, et al.
    Sci Rep, 2021 07 19;11(1):14642.
    PMID: 34282166 DOI: 10.1038/s41598-021-93989-w
    As a cheap source of high-quality protein, healthy fats and essential nutrients, dried fish is a common item in the daily diet of the Bangladesh populace. In this study, ten types of widely consumed dried fish (H. neherius, T. lepturu, P.chinensis, P. affinis, A. mola, P. microdon, I. megaloptera, C. dussumieri, L. calcarifer, and G. chapra) were analyzed for Cr, Mn, Fe, Co, Cu, Zn, Se, Rb, Hg, Pb, Ni and As by using an Energy Dispersive X-ray Fluorescence (EDXRF) technique. The concentration of the studied metals was found in the order Fe > Zn > Hg > Cu > Se > Cr > Mn > Co > Rb > Pb, while As and Ni were below the limit of detection. All fish species showed moderate to high pollution, where the species H. Neherius and P. Chinensis are the most and least polluted ones, respectively. The probable source of contamination is the leaching from the drying pans into the fish samples, atmospheric deposition, anthropogenic contamination, etc. of the water body where these fish were harvested. The calculated hazard index for the general population was below the maximum limiting value (i.e., 
  9. Design of a Sub-Picosecond Jitter with Adjustable-Range CMOS Delay-Locked Loop for High-Speed and Low-Power Applications
    Abdulrazzaq BI, Ibrahim OJ, Kawahito S, Sidek RM, Shafie S, Yunus NA, et al.
    Sensors (Basel), 2016 Sep 28;16(10).
    PMID: 27690040
    A Delay-Locked Loop (DLL) with a modified charge pump circuit is proposed for generating high-resolution linear delay steps with sub-picosecond jitter performance and adjustable delay range. The small-signal model of the modified charge pump circuit is analyzed to bring forth the relationship between the DLL's internal control voltage and output time delay. Circuit post-layout simulation shows that a 0.97 ps delay step within a 69 ps delay range with 0.26 ps Root-Mean Square (RMS) jitter performance is achievable using a standard 0.13 µm Complementary Metal-Oxide Semiconductor (CMOS) process. The post-layout simulation results show that the power consumption of the proposed DLL architecture's circuit is 0.1 mW when the DLL is operated at 2 GHz.
  10. Fulltext Diabetic ketoacidosis at diagnosis of type 1 diabetes mellitus in Malaysian children and adolescents
    Hong JYH, Jalaludin MY, Mohamad Adam B, Fuziah MZ, Wu LL, Rasat R, et al.
    Malays Fam Physician, 2015;10(3):11-18.
    PMID: 27570603 MyJurnal
    Background: Diabetic ketoacidosis (DKA) is a late presentation of newly diagnosed type 1 diabetes mellitus (DM) in children. The aim of this study was to determine the clinical characteristics of type 1 DM at presentation so that appropriate actions can be taken to promote early diagnosis.
    Methods: This was a retrospective cohort review from a patient registry database. Data on all patients younger than 20 years old diagnosed with type 1 DM who had been registered with the Malaysian Diabetes in Children and Adolescents Registry (DiCARE) from its inception in 2006 until 2009 were analysed.
    Results: The study included 490 children and adolescents, out of which 57.1% were female. The mean (SD) age at diagnosis was 7.5 (3.7) years, which increased from year 2000 to 2009 [6.6 (3.3) years to 9.6 (3.5) years; p = 0.001]. An increasing percentage of DKA at diagnosis was observed from year 2000 (54.5%) to year 2009 (66.7%), which remained high and leveled between 54.5% and 75.0%. DKA was more common in patients with normal weight (p = 0.002) with no significant association with age, gender, ethnicity and status of family history of diabetes mellitus.
    Conclusion: An increasing trend of age at diagnosis of patients with type 1 DM was observed. Besides that, proportion of DKA at diagnosis had remained high over the past decade. This study found that normal weight was associated with status of DKA, thus more detailed investigations are required to determine the risk factors for DKA.
  11. Fulltext Effectiveness of pictorial health warning on cigarette packages: a cross-sectional study in Sarawak, Malaysia
    Rahman MM, Arif MT, Abd Razak MF, Suhaili MR, Tambi Z, Akoi C, et al.
    Malays Fam Physician, 2015;10(3):19-26.
    PMID: 27570604 MyJurnal
    Introduction: Specific health warning placed on the tobacco product packages is considered as an effective and low-cost method for increasing the knowledge and awareness among the community. Thus, a study was conducted to assess the perception of pictorial health warnings (PHWs) against smoking among the adult rural population of Sarawak.
    Methods: Cross-sectional data were collected from 10 villages in Kota Samarahan and Kuching Division by face to face interview using modified Global Adult Tobacco Survey questionnaire. Nonprobability sampling method was adopted to select the villages. All the households of the selected villages were visited and an adult member was selected randomly from each house irrespective of the sex. After missing value imputation, 1000 data were analysed using statistical software IBM SPSS 20.0 version.
    Results: Analysis showed that 28.8% of the respondents were current smokers, 7.8% were past smokers and the rest were non-smokers. Six items of pictorial health warnings were evaluated with five point Likert’s scales for attractiveness, fearfulness and adequacy of the information. Analysis revealed that the majority of the respondents had perceived awareness on PHWs, but the smokers believed that this was not adequate to make them quit smoking. Only one-fifth (19.7%) of them reported that current pictorial health warnings were sufficient to motivate people to quit smoking.
    Conclusion: Though the PHWs on cigarette packages are appealing, it is not sufficient as a reason to stop smoking. Thus, an approach using an integrated anti-tobacco public health programme should be focused into the specific targeted community
  12. Designing the angiogenic inhibitor for brain tumor via disruption of VEGF and IL17A expression
    Khan MS, Majid AM, Iqbal MA, Majid AS, Al-Mansoub M, Haque RS
    Eur J Pharm Sci, 2016 Oct 10;93:304-18.
    PMID: 27552907 DOI: 10.1016/j.ejps.2016.08.032
    Glioblastoma multiforme is a highly malignant, heterogenic, and drug resistant tumor. The blood-brain barrier (BBB), systemic cytotoxicity, and limited specificity are the main obstacles in designing brain tumor drugs. In this study a computational approach was used to design brain tumor drugs that could downregulate VEGF and IL17A in glioblastoma multiforme type four. Computational screening tools were used to evaluate potential candidates for antiangiogenic activity, target binding, BBB permeability, and ADME physicochemical properties. Additionally, in vitro cytotoxicity, migration, invasion, tube formation, apoptosis, ROS and ELISA assays were conducted for molecule 6 that was deemed most likely to succeed. The efflux ratio of membrane permeability and calculated docking scores of permeability to glycoproteins (P-gps) were used to determine the BBB permeability of the molecules. The results showed BBB permeation for molecule 6, with the predicted efficiency of 0.55kcal/mol and binding affinity of -37kj/mol corresponding to an experimental efflux ratio of 0.625 and predicted -15kj/mol of binding affinity for P-gps. Molecule 6 significantly affected the angiogenesis pathways by 2-fold downregulation of IL17A and VEGF through inactivation of active sites of HSP90 (predicted binding: -37kj/mol, predicted efficiency: 0.55kcal/mol) and p23 (predicted binding: 12kj/mol, predicted efficiency: 0.17kcal/mol) chaperon proteins. Additionally, molecule 6 activated the 17.38% relative fold of ROS level at 18.3μg/mL and upregulated the caspase which lead the potential synergistic apoptosis through the antiangiogenic activity of molecule 6 and thereby the highly efficacious anticancer upshot. The results indicate that the binding of the molecules to the therapeutic target is not essential to produce a lethal effect on cancer cells of the brain and that antiangiogenic efficiency is much more important.
  13. Stage-directed individualized therapy in esophageal cancer
    Goense L, van Rossum PS, Kandioler D, Ruurda JP, Goh KL, Luyer MD, et al.
    Ann N Y Acad Sci, 2016 10;1381(1):50-65.
    PMID: 27384385 DOI: 10.1111/nyas.13113
    Esophageal cancer is the eighth most common cancer worldwide, and the incidence of esophageal carcinoma is rapidly increasing. With the advent of new staging and treatment techniques, esophageal cancer can now be managed through various strategies. A good understanding of the advances and limitations of new staging techniques and how these can guide in individualizing treatment is important to improve outcomes for esophageal cancer patients. This paper outlines the recent progress in staging and treatment of esophageal cancer, with particularly attention to endoscopic techniques for early-stage esophageal cancer, multimodality treatment for locally advanced esophageal cancer, assessment of response to neoadjuvant treatment, and the role of cervical lymph node dissection. Furthermore, advances in robot-assisted surgical techniques and postoperative recovery protocols that may further improve outcomes after esophagectomy are discussed.
  14. Is There An Optimal Time for Performing Cranioplasties? Results from a Prospective Multinational Study
    Quah BL, Low HL, Wilson MH, Bimpis A, Nga VDW, Lwin S, et al.
    World Neurosurg, 2016 Oct;94:13-17.
    PMID: 27368511 DOI: 10.1016/j.wneu.2016.06.081
    BACKGROUND: The optimal timing of cranioplasty remains uncertain.

    OBJECTIVE: We hypothesized that the risk of infections after primary cranioplasty in adult patients who underwent craniectomies for non-infection-related indications are no different when performed early or delayed. We tested this hypothesis in a prospective, multicenter, cohort study.

    METHODS: Data were collected prospectively from 5 neurosurgical centers in the United Kingdom, Malaysia, Singapore, and Bangladesh. Only patients older than 16 years from the time of the non-infection-related craniectomy were included. The recruitment period was over 17 months, and postoperative follow-up was at least 6 months. Patient baseline characteristics, rate of infections, and incidence of hydrocephalus were collected.

    RESULTS: Seventy patients were included in this study. There were 25 patients in the early cranioplasty cohort (cranioplasty performed before 12 weeks) and 45 patients in the late cranioplasty cohort (cranioplasty performed after 12 weeks). The follow-up period ranged between 16 and 34 months (mean, 23 months). Baseline characteristics were largely similar but differed only in prophylactic antibiotics received (P = 0.28), and primary surgeon performing cranioplasty (P = 0.15). There were no infections in the early cranioplasty cohort, whereas 3 infections were recorded in the late cohort. This did not reach statistical significance (P = 0.55).

    CONCLUSIONS: Early cranioplasty in non-infection-related craniectomy is relatively safe. There does not appear to be an added advantage to delaying cranioplasties more than 12 weeks after the initial craniectomy in terms of infection reduction. There was no significant difference in infection rates or risk of hydrocephalus between the early and late cohorts.

  15. Fulltext Phosphorylated and Nonphosphorylated PfMAP2 Are Localized in the Nucleus, Dependent on the Stage of Plasmodium falciparum Asexual Maturation
    Dahalan FA, Sidek HM, Murtey MD, Embi MN, Ibrahim J, Fei Tieng L, et al.
    Biomed Res Int, 2016;2016:1645097.
    PMID: 27525262 DOI: 10.1155/2016/1645097
    Plasmodium falciparum mitogen-activated protein (MAP) kinases, a family of enzymes central to signal transduction processes including inflammatory responses, are a promising target for antimalarial drug development. Our study shows for the first time that the P. falciparum specific MAP kinase 2 (PfMAP2) is colocalized in the nucleus of all of the asexual erythrocytic stages of P. falciparum and is particularly elevated in its phosphorylated form. It was also discovered that PfMAP2 is expressed in its highest quantity during the early trophozoite (ring form) stage and significantly reduced in the mature trophozoite and schizont stages. Although the phosphorylated form of the kinase is always more prevalent, its ratio relative to the nonphosphorylated form remained constant irrespective of the parasites' developmental stage. We have also shown that the TSH motif specifically renders PfMAP2 genetically divergent from the other plasmodial MAP kinase activation sites using Neighbour Joining analysis. Furthermore, TSH motif-specific designed antibody is crucial in determining the location of the expression of the PfMAP2 protein. However, by using immunoelectron microscopy, PPfMAP2 were detected ubiquitously in the parasitized erythrocytes. In summary, PfMAP2 may play a far more important role than previously thought and is a worthy candidate for research as an antimalarial.
  16. Fulltext Synthesis, PASS-Predication and in Vitro Antimicrobial Activity of Benzyl 4-O-benzoyl-α-l-rhamnopyranoside Derivatives
    Matin MM, Nath AR, Saad O, Bhuiyan MM, Kadir FA, Abd Hamid SB, et al.
    Int J Mol Sci, 2016 Aug 27;17(9).
    PMID: 27618893 DOI: 10.3390/ijms17091412
    Benzyl α-l-rhamnopyranoside 4, obtained by both conventional and microwave assisted glycosidation techniques, was subjected to 2,3-O-isopropylidene protection to yield compound 5 which on benzoylation and subsequent deprotection of isopropylidene group gave the desired 4-O-benzoylrhamnopyranoside 7 in reasonable yield. Di-O-acetyl derivative of benzoate 7 was prepared to get newer rhamnopyranoside. The structure activity relationship (SAR) of the designed compounds was performed along with the prediction of activity spectra for substances (PASS) training set. Experimental studies based on antimicrobial activities verified the predictions obtained by the PASS software. Protected rhamnopyranosides 5 and 6 exhibited slight distortion from regular ¹C₄ conformation, probably due to the fusion of pyranose and isopropylidene ring. Synthesized rhamnopyranosides 4-8 were employed as test chemicals for in vitro antimicrobial evaluation against eight human pathogenic bacteria and two fungi. Antimicrobial and SAR study showed that the rhamnopyranosides were prone against fungal organisms as compared to that of the bacterial pathogens. Interestingly, PASS prediction of the rhamnopyranoside derivatives 4-8 were 0.49 < Pa < 0.60 (where Pa is probability 'to be active') as antibacterial and 0.65 < Pa < 0.73 as antifungal activities, which showed significant agreement with experimental data, suggesting rhamnopyranoside derivatives 4-8 were more active against pathogenic fungi as compared to human pathogenic bacteria thus, there is a more than 50% chance that the rhamnopyranoside derivative structures 4-8 have not been reported with antimicrobial activity, making it a possible valuable lead compound.
  17. Flavonoids-Rich Orthosiphon stamineus Extract as New Candidate for Angiotensin I-Converting Enzyme Inhibition: A Molecular Docking Study
    Shafaei A, Sultan Khan MS, F A Aisha A, Abdul Majid AM, Hamdan MR, Mordi MN, et al.
    Molecules, 2016 Nov 09;21(11).
    PMID: 27834876
    This study aims to evaluate the in vitro angiotensin-converting enzyme (ACE) inhibition activity of different extracts of Orthosiphon stamineus (OS) leaves and their main flavonoids, namely rosmarinic acid (RA), sinensetin (SIN), eupatorin (EUP) and 3'-hydroxy-5,6,7,4'-tetramethoxyflavone (TMF). Furthermore, to identify possible mechanisms of action based on structure-activity relationships and molecular docking. The in vitro ACE inhibition activity relied on determining hippuric acid (HA) formation from ACE-specific substrate (hippuryl-histidyl-leucine (HHL)) by the action of ACE enzyme. A High Performance Liquid Chromatography method combined with UV detection was developed and validated for measurement the concentration of produced HA. The chelation ability of OS extract and its reference compounds was evaluated by tetramethylmurexide reagent. Furthermore, molecular docking study was performed by LeadIT-FlexX: BioSolveIT's LeadIT program. OS ethanolic extract (OS-E) exhibited highest inhibition and lowest IC50 value (45.77 ± 1.17 µg/mL) against ACE compared to the other extracts. Among the tested reference compounds, EUP with IC50 15.35 ± 4.49 µg/mL had highest inhibition against ACE and binding ability with Zn (II) (56.03% ± 1.26%) compared to RA, TMF and SIN. Molecular docking studies also confirmed that flavonoids inhibit ACE via interaction with the zinc ion and this interaction is stabilized by other interactions with amino acids in the active site. In this study, we have demonstrated that changes in flavonoids active core affect their capacity to inhibit ACE. Moreover, we showed that ACE inhibition activity of flavonoids compounds is directly related to their ability to bind with zinc ion in the active site of ACE enzyme. It was also revealed that OS extract contained high amount of flavonoids other than RA, TMF, SIN and EUP. As such, application of OS extract is useful as inhibitors of ACE.
  18. Fulltext Serological measures to assess the efficacy of malaria control programme on Ambae Island, Vanuatu
    Idris ZM, Chan CW, Mohammed M, Kalkoa M, Taleo G, Junker K, et al.
    Parasit Vectors, 2017 Apr 26;10(1):204.
    PMID: 28441959 DOI: 10.1186/s13071-017-2139-z
    BACKGROUND: Seroepidemiology can provide evidence for temporal changes in malaria transmission and is an important tool to evaluate the effectiveness of control interventions. During the early 2000s, Vanuatu experienced an acute increase in malaria incidence due to a lapse in funding for vector control. After the distribution of subsidised insecticide-treated nets (ITNs) resumed in 2003, malaria incidence decreased in the subsequent years. This study was conducted to find the serological evidence supporting the impact of ITN on exposure to Anopheles vector bites and parasite prevalence.

    METHODS: On Ambae Island, blood samples were collected from 231 and 282 individuals in 2003 and 2007, respectively. Parasite prevalence was determined by microscopy. Antibodies to three Plasmodium falciparum (PfSE, PfMSP-119, and PfAMA-1) and three Plasmodium vivax (PvSE, PvMSP-119, and PvAMA-1) antigens, as well as the Anopheles-specific salivary antigen gSG6, were detected by ELISA. Age-specific seroprevalence was analysed using a reverse catalytic modelling approach to estimate seroconversion rates (SCRs).

    RESULTS: Parasite rate decreased significantly (P 

  19. Geo-accumulation index and contamination factors of heavy metals (Zn and Pb) in urban river sediment
    Haris H, Looi LJ, Aris AZ, Mokhtar NF, Ayob NAA, Yusoff FM, et al.
    Environ Geochem Health, 2017 Dec;39(6):1259-1271.
    PMID: 28484873 DOI: 10.1007/s10653-017-9971-0
    The aim of the present study was to appraise the levels of heavy metal contamination (Zn and Pb) in sediment of the Langat River (Selangor, Malaysia). Samples were collected randomly from 15 sampling stations located along the Langat River. The parameters measured were pH, redox potential, salinity, electrical conductivity, loss of ignition, cation exchanges capacity (Na, Mg, Ca, K), and metal ions (Zn and Pb). The geo-accumulation index (I geo) and contamination factor (C f) were applied to determine and classify the magnitude of heavy metal pollution in this urban river sediment. Results revealed that the I geo of Pb indicated unpolluted to moderately polluted sediment at most of the sampling stations, whereas Zn was considered to be within background concentration. The I geo results were refined by the C f values, which showed Pb with very high C f at 12 stations. Zinc, on the other hand, had low to moderate C f values. These findings indicated that the sediment of the Langat River is severely polluted with Pb. The Zn concentration at most sampling points was well below most sediment quality guidelines. However, 40% of the sampling points were found to have a Pb concentration higher than the consensus-based probable effect concentration of 128 mg/kg (concentrations above this value are likely to cause harmful effects). This result not only highlights the severity of Pb pollution in the sediment of the Langat River, but also the potential risk it poses to the environment.
  20. Carbon nanotube-based aptasensor for sensitive electrochemical detection of whole-cell Salmonella
    Hasan MR, Pulingam T, Appaturi JN, Zifruddin AN, Teh SJ, Lim TW, et al.
    Anal Biochem, 2018 08 01;554:34-43.
    PMID: 29870692 DOI: 10.1016/j.ab.2018.06.001
    In this study, an amino-modified aptasensor using multi-walled carbon nanotubes (MWCNTs)-deposited ITO electrode was prepared and evaluated for the detection of pathogenic Salmonella bacteria. An amino-modified aptamer (ssDNA) which binds selectively to whole-cell Salmonella was immobilised on the COOH-rich MWCNTs to produce the ssDNA/MWCNT/ITO electrode. The morphology of the MWCNT before and after interaction with the aptamers were observed using scanning electron microscopy (SEM). Cyclic voltammetry and electrochemical impedance spectroscopy techniques were used to investigate the electrochemical properties and conductivity of the aptasensor. The results showed that the impedance measured at the ssDNA/MWCNT/ITO electrode surface increased after exposure to Salmonella cells, which indicated successful binding of Salmonella on the aptamer-functionalised surface. The developed ssDNA/MWCNT/ITO aptasensor was stable and maintained linearity when the scan rate was increased from 10 mV s-1 to 90 mV s-1. The detection limit of the ssDNA/MWCNT/ITO aptasensor, determined from the sensitivity analysis, was found to be 5.5 × 101 cfu mL-1 and 6.7 × 101 cfu mL-1 for S. Enteritidis and S. Typhimurium, respectively. The specificity test demonstrated that Salmonella bound specifically to the ssDNA/MWCNT/ITO aptasensor surface, when compared with non-Salmonella spp. The prepared aptasensor was successfully applied for the detection of Salmonella in food samples.
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