Displaying publications 21 - 40 of 198 in total

Abstract:
Sort:
  1. Phage display of recombinant antibodies toward Burkholderia pseudomallei exotoxin
    Nathan S, Li H, Mohamed R, Embi N
    J. Biochem. Mol. Biol. Biophys., 2002 Feb;6(1):45-53.
    PMID: 12186782
    We have used the phagemid pComb3H to construct recombinant phages displaying the single chain variable fragment (ScFv) towards exotoxin of Burkholderia pseudomallei. Variable heavy and light chain fragments were amplified from the hybridoma 6E6A8F3B line, with a wide spectrum of primers specific to mouse antibody genes. Through overlapping extension polymerase chain reaction, the heavy and light chain fragments were linked to form the ScFv which was subsequently cloned into the phage display vector and transformed into ER2537 cells to yield a complexity of 10(8) clones. The transformants were screened by four rounds of biopanning against the exotoxin and resulted in selective enrichment of exotoxin-binding antibodies by 301 fold. The phage pool from the final round of selection displayed antibodies of high-affinity to the exotoxin as demonstrated by ELISA. Several clones were selected randomly from this pool and analysed by restriction enzyme digestion, fingerprinting and sequencing. Restriction analysis confirmed that all clones carried a 700-800 bp insert whose sequences, in general, corresponded to that of mouse IgG. Fingerprinting profiles delineated the antibodies into two families with different CDR sequences.
  2. Fulltext Wilson's disease--a review of cases at University Hospital, Kuala Lumpur
    Mohamed R, Tan CT, Wong NW
    Med J Malaysia, 1994 Mar;49(1):49-52.
    PMID: 8057991
    The clinical course of 18 patients with Wilson's disease is reported. There were 13 males and five females of whom one is Malay. The prevalence of Wilson's disease in Malaysia is probably the same as elsewhere. Being a genetic syndrome, the genetic carrier rate for Wilson's disease is probably lower amongst the Malays. At diagnosis, the clinical signs were predominantly hepatic in 10 patients, neurological in five patients with three asymptomatic cases. All patients were commenced on penicillamine but poor compliance was observed in many patients. Two patients defaulted follow-up and seven patients died. Out of the nine surviving patients, only four are well with no clinical symptoms.
  3. Fulltext Neonatal group B beta-haemolytic streptococcal infection in Kuala Lumpur
    Minhaj AA, Jamal F, Mohamed R
    Med J Malaysia, 1980 Dec;35(2):117-21.
    PMID: 7022149
    First six cases of neonatal group B beta-haemolytic streptococcal sepsis in GHKL & Maternity Hospital K.L. were reported and in one third, it was fatal. Five of the cases were 'early - onset' type and one was 'late - onset' type. While maternal infant transmission of the disease is important in the 'early - onset' type, environmental sources of infection are also significant. No gestational age or birthweight is spared from the disease. Finally, there are cases of 'early - onset' GBS sepsis presenting like hyaline membrane disease of the newborn and it is important to find ways to distinguish them which so far has not been satisfactory.
  4. Antibody to Pseudomonas pseudomallei exotoxin in sheep exposed to natural infection
    Ismail G, Mohamed R, Rohana S, Sharifah HS, Embi N
    Vet Microbiol, 1991 May;27(3-4):277-82.
    PMID: 1882505
    Specific antibody to Pseudomonas pseudomallei exotoxin was detected in sheep sera exposed to natural infection. An enzyme-linked immunosorbent assay (ELISA) was used. Serum antitoxin was present in 49.3% of sera obtained from a flock of sheep naturally exposed to P. pseudomallei infection. Among these sera, 17.0% gave titers of 10,000. In contrast, serum antitoxin was present in only 6.0% of sera collected from sheep kept on a melioidosis-free farm. The ELISA reactivity of all positive sera could be completely absorbed with purified P. pseudomallei exotoxin. Similarly, preincubation of the exotoxin-coated wells with specific antiserum inhibited the ELISA reactivity of sheep sera. The results indicate that exotoxin is produced in vivo during infection by P. pseudomallei.
  5. A defect in DNA topoisomerase II activity in ataxia-telangiectasia cells
    Mohamed R, Pal Singh S, Kumar S, Lavin MF
    Biochem Biophys Res Commun, 1987 Nov 30;149(1):233-8.
    PMID: 2825700
    DNA topoisomerase type I and II activities were determined by serial dilution in nuclear extracts from control and ataxia-telangiectasia lymphoblastoid cells. Topoisomerase I activity, assayed by relaxation of supercoiled plasmid DNA, was found to be approximately the same in both cell types. In order to remove interference from topoisomerase I, the activity of topoisomerase II was measured by the unknotting of knotted P4 phage DNA in the presence of ATP. The activity of topoisomerase II was markedly reduced in two ataxia-telangiectasia cell lines, AT2ABR and AT8ABR, compared to controls. This reduction in activity was detected with increasing concentration of protein and in time course experiments at a single protein concentration. A third cell line, AT3ABR, did not have a detectably lower activity of topoisomerase II when assayed under these conditions. The difference in topoisomerase II activity in the ataxia-telangiectasia cell lines examined may reflect to some extent the heterogeneity observed in this syndrome.
  6. Method validation and determination of heavy metals in cocoa beans and cocoa products by microwave assisted digestion technique with inductively coupled plasma mass spectrometry
    Mohamed R, Zainudin BH, Yaakob AS
    Food Chem, 2020 Jan 15;303:125392.
    PMID: 31446362 DOI: 10.1016/j.foodchem.2019.125392
    In this article, an easy and quick method based on microwave assisted acid digestion technique prior to quantification using inductively coupled plasma mass spectrometry for the analysis of heavy metals in cocoa beans, cocoa powder and chocolate was established and validated for arsenic (As), cadmium (Cd), lead (Pb), and antimony (Sb). Limit of quantification for all elements were product dependent and varies from 7.84 to 194.52 µg/kg. The recoveries of the heavy metals at 250 and 1000 µg/kg spiking levels were ranged between 96.27-108.75%, 90.43-101.97% and 89.72-106.26% for cocoa beans, cocoa powder, and chocolate, respectively. Relative standard deviation values obtained were all below 20% and the expanded uncertainty measurements for the elements were less than 25%. The analysis of real samples found that the concentration level is far from the national alarming level except for cadmium in cocoa beans.
  7. Fulltext Practical approach in hepatitis B e antigen-negative individuals to identify treatment candidates
    Azmi AN, Tan SS, Mohamed R
    World J Gastroenterol, 2014 Sep 14;20(34):12045-55.
    PMID: 25232242 DOI: 10.3748/wjg.v20.i34.12045
    The natural history of chronic hepatitis B is characterized by different phases of infection, and patients may evolve from one phase to another or may revert to a previous phase. The hepatitis B e antigen (HBeAg)-negative form is the predominant infection worldwide, which consists of individuals with a range of viral replication and liver disease severity. Although alanine transaminase (ALT) remains the most accessible test available to clinicians for monitoring the liver disease status, further evaluations are required for some patients to assess if treatment is warranted. Guidance from practice guidelines together with thorough investigations and classifications of patients ensure recognition of who needs which level of care. This article aims to assist physicians in the assessment of HBeAg-negative individuals using liver biopsy or non-invasive tools such as hepatitis B s antigen quantification and transient elastography in addition to ALT and hepatitis B virus DNA, to identify who will remain stable, who will reactivate or at risk of disease progression hence will benefit from timely initiation of anti-viral therapy.
  8. Fulltext Phylogenetic Relatedness of Several Agarwood-Producing Taxa (Thymelaeaceae) from Indonesia
    Lee SY, Turjaman M, Mohamed R
    Trop Life Sci Res, 2018 Jul;29(2):13-28.
    PMID: 30112138 MyJurnal DOI: 10.21315/tlsr2018.29.2.2
    Indonesia is home to several tree taxa that are harvested for agarwood. This highly valuable oleoresin ironically was the cause for some species to become vulnerable due to gluttonous human activity. However, information on the genetic diversity of these endangered trees is limited. In this study, 28 specimens representing eight species from two genera, Aquilaria and Gyrinops, were collected from ex-situ and in-situ populations in Indonesia. Phylogenetic analysis conducted on DNA sequences of the nuclear ribosomal internal transcribed spacer (ITS) and the trnL-trnF intergenic spacer regions, revealed that Aquilaria and Gyrinops are paraphyletic when Aquilaria cumingiana is excluded. The phylogenetic analysis for ITS and trnL-trnF showed capability to categorise agarwood-producing species based on their regions: East Indonesia and West Indonesia, using Wallace's Line as the divider. In addition, we discuss challenges in species identification and taxonomy of agarwood-producing genera, and their conservation efforts in Indonesia.
  9. Fulltext Regulatory role of GSK3β in the activation of NF-κB and modulation of cytokine levels in Burkholderia pseudomallei-infected PBMC isolated from streptozotocin-induced diabetic animals
    Maniam P, Nurul Aiezzah Z, Mohamed R, Embi N, Hasidah MS
    Trop Biomed, 2015 Mar;32(1):36-48.
    PMID: 25801253
    Increased susceptibility of diabetics to melioidosis, a disease caused by the Burkholderia pseudomallei bacterium is believed to be attributed to dysfunction of the innate immune system. However, the underlying mechanism of the innate susceptibility is not well-understood. Glycogen synthase kinase-3β (GSK3β) plays an important role in the innate inflammatory response caused by bacterial pathogens. The present study was conducted to investigate the effects of GSK3β inhibition by LiCl on levels of pro- and anti-inflammatory cytokines; and the activity of transcription factor NF-κB in B. pseudomallei-infected peripheral blood mononuclear cells (PBMC) derived from diabetic-induced and normal Sprague Dawley rats. In addition, the effects of LiCl on intracellular bacterial counts were also investigated. Infection of PBMC from diabetic and normal rats with B. pseudomallei resulted in elevated levels of cytokines (TNF-α, IL-12 and IL-10) and phosphorylation of NF-κB in both cell types. Intracellular bacterial counts decreased with time in both cell types during infection. However bacterial clearance was less prominent in diabetic PBMC. Burkholderia pseudomallei infection also caused inactivation (Ser9 phosphorylation) of GSK3β in normal PBMC, an effect absent in infected diabetic PBMC. Inhibition of GSK3β by LiCl lowered the levels of pro-inflammatory cytokines (TNF-α and IL-12) in both normal and diabetic PBMC. Similarly, phosphorylated NF- κB (pNF-κB) levels in both cell types were decreased with LiCl treatment. Also, LiCl was able to significantly decrease the intracellular bacterial count in normal as well as diabetic PBMC. Interestingly, the levels of anti-inflammatory cytokine IL-10 in both normal and diabetic PBMC were further elevated with GSK3β inhibition. More importantly, GSK3β in infected diabetic PBMC was inactivated as in their non-diabetic counterparts upon LiCl treatment. Taken together, our results suggest that inhibition of dysregulated GSK3β in diabetic PBMC resulted in the inactivation of NF-κB and modulation of inflammatory cytokine levels. This is evidence that dysregulation of GSK3β is a contributing factor in the molecular basis of innate dysfunction and susceptibility of diabetic host to melioidosis infection.
  10. Fatty liver is associated with advanced fibrosis but does not predict adverse outcomes in patients with chronic hepatitis B
    Wong SW, Chan WK, Mohamed R
    J Viral Hepat, 2020 12;27(12):1297-1305.
    PMID: 32668489 DOI: 10.1111/jvh.13361
    Hepatic steatosis is increasingly common and has been implicated in progression of liver fibrosis in chronic hepatitis B (CHB) patients. We aimed to investigate the impact of hepatic steatosis on liver fibrosis and clinical outcomes in CHB patients. Consecutive CHB patients who underwent transient elastography between 2013 and 2017 at a tertiary hospital were included in this longitudinal cohort study. Presence of hepatic steatosis was defined as controlled attenuation parameter, CAP ≥ 248 dB/m, while advanced liver fibrosis was defined as liver stiffness measurement, LSM ≥ 9.4 kPa. Cardiovascular events, liver-related complications, malignancy and mortality and a composite of these outcomes were evaluated with Kaplan-Meier analysis and Cox proportional hazards regression. Our study cohort included 614 patients with median follow-up of 45 (32-63) months. Hepatic steatosis was present in 294 patients (47.9%), and advanced liver fibrosis was present in 127 patients (21.0%). Presence of hepatic steatosis (OR: 1.956, 95% CI: 1.250-3.060) and diabetes mellitus (OR: 3.507, 95% CI: 2.069-5.944) was independently associated with advanced fibrosis. Advanced fibrosis was independently associated with composite outcome (HR: 2.496, 95% CI: 1.352-4.606), liver-related complications (HR: 3.765, 95% CI: 1.380-10.271) and mortality (HR: 3.632, 95% CI: 1.342-9.826), but not cardiovascular events and malignancy. Hepatic steatosis was not associated with any adverse outcomes. We conclude that hepatic steatosis is common and associated with advanced fibrosis in CHB patients. Unlike advanced fibrosis, hepatic steatosis does not predict adverse outcomes in CHB patients.
  11. Fulltext Perception of family satisfaction with care at critical care setting Hospital University Sains Malaysia: a pilot study
    Mahyiddin NS, Mohamed R, Jan Mohamed HJ
    The Malaysian Journal of Nursing, 2015;7(1):32-37.
    MyJurnal
    Family members' satisfaction has become an important measurement in determining the quality of care of patients in the critical care setting. The aims of the study were to determine the satisfaction level of family members, to determine the reliability of family satisfaction and its subscales, to identify mean of each question and their subscales. A cross-sectional study was conducted on 30 family members who accompanied patients during intensive care admission. The study was conducted in a critical care setting in
    a high dependency unit (HDU) and cardiac intensive care unit (CCU), Hospital University Sains Malaysia (Hospital USM). The data was collected from October 2012 to January 2013. The Critical Care Family Satisfaction Survey (CCFSS) Malay version was used to measure family satisfaction in addition to the collection of demographic data. The statistical analysis used a descriptive approach. Ethical approval was obtained prior to data collection. Majority of the respondents were female: 23 (76.7%). Mean age was 35.67 years (SD=12.83) and the score of overall satisfaction level was 78.80 (SD=13.88). The Cronbach's alpha was 0.96. A majority of the respondents, 19 (63.3%) were satisfied with the care provided. This study showed that a majority of family members were slightly satisfied with the care that was provided in a critical
    care setting at HUSM. It also showed that families play an important role in giving support and hope to patients.
    Study site: HDU and CCU, Hospital Universiti Sains Malaysia (HUSM), Kelantan, Malaysia
  12. Fulltext A New Method for a Piezoelectric Energy Harvesting System Using a Backtracking Search Algorithm-Based PI Voltage Controller
    Sarker MR, Mohamed A, Mohamed R
    Micromachines (Basel), 2016 Sep 23;7(10).
    PMID: 30404344 DOI: 10.3390/mi7100171
    This paper presents a new method for a vibration-based piezoelectric energy harvesting system using a backtracking search algorithm (BSA)-based proportional-integral (PI) voltage controller. This technique eliminates the exhaustive conventional trial-and-error procedure for obtaining optimized parameter values of proportional gain (Kp), and integral gain (Ki) for PI voltage controllers. The generated estimate values of Kp and Ki are executed in the PI voltage controller that is developed through the BSA optimization technique. In this study, mean absolute error (MAE) is used as an objective function to minimize output error for a piezoelectric energy harvesting system (PEHS). The model for the PEHS is designed and analyzed using the BSA optimization technique. The BSA-based PI voltage controller of the PEHS produces a significant improvement in minimizing the output error of the converter and a robust, regulated pulse-width modulation (PWM) signal to convert a MOSFET switch, with the best response in terms of rise time and settling time under various load conditions.
  13. Gynura procumbens ethanol extract and its fractions inhibit macrophage derived foam cell formation
    Manogaran M, Vuanghao L, Mohamed R
    J Ethnopharmacol, 2020 Mar 01;249:112410.
    PMID: 31747560 DOI: 10.1016/j.jep.2019.112410
    ETHNOPHARMACOLOGY RELEVANCE: Gynura procumbens (Lour.) Merr. displayed cardio-protective effect that may prevent atherogenesis. The primary underlying pathological process of cardiovascular disease is atherosclerosis. Atherosclerotic lesion composed of macrophages, T cells and other immune cells which incorporated with cholesterol that infiltrates from the blood.

    AIM OF THE STUDY: The present study was performed to determine underlying mechanism of G. procumbens ethanol extract and its fractions such as aqueous, chloroform, ethyl acetate and hexane affect macrophage derived foam cell formation.

    MATERIALS AND METHODS: Lipid droplets accumulation in treated macrophages were visualized by Oil Red O staining while the total cholesterol present in the treated macrophages were measured using Cholestryl Ester quantification assay kit. Enzyme-Linked Immunosorbent Assay (ELISA) were used to detect TNF-α and IL-1β secretion in the supernatant of treated macrophages. Gene expression of Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) and ATP-binding cassette transporter A-1 (ABCA-1) in treated macrophages were analyzed using Real-Time Quantitative Polymerase Chain Reaction (RT-qPCR).

    RESULTS: G. procumbens ethanol extract and its fractions reduced lipid droplet accumulation and total cholesterol in oxLDL-treated macrophages together with significantly reduction of TNF-α and IL-1β secretions in supernatant oxLDL-treated macrophages. LOX-1 gene expression was significantly reduced when G. procumbens ethanol extract and its fractions were added in oxDL-treated macrophages. In contrast, G. procumbens ethanol extract and its fractions significantly increased the expression of ABCA-1 gene in oxLDL-treated macrophages.

    CONCLUSION: In conclusion, G. procumbens ethanol extract and its fractions inhibit the formation of macrophage derived foam cell by reducing TNF-α and IL-1β expression, which usually highly expressed in atherosclerotic plaques, suppressing scavenger receptor LOX-1 gene that binds oxLDL but induced ABCA-1 gene that mediate lipid efflux from macrophages.

  14. Fulltext Stimulatory Secretions of Airway Epithelial Cells Accelerate Early Repair of Tracheal Epithelium
    Kardia E, Mohamed R, Yahaya BH
    Sci Rep, 2017 09 15;7(1):11732.
    PMID: 28916766 DOI: 10.1038/s41598-017-11992-6
    Airway stem/progenitor epithelial cells (AECs) are notable for their differentiation capacities in response to lung injury. Our previous finding highlighted the regenerative capacity of AECs following transplantation in repairing tracheal injury and reducing the severity of alveolar damage associated acute lung injury in a rabbit model. The goal of this study is to further investigate the potential of AECs to re-populate the tracheal epithelium and to study their stimulatory effect on inhibiting pro-inflammatory cytokines, epithelial cell migration and proliferation, and epithelial-to-mesenchymal transition (EMT) process following tracheal injury. Two in vitro culture assays were applied in this study; the direct co-culture assay that involved a culture of decellularised tracheal epithelium explants and AECs in a rotating tube, and indirect co-culture assay that utilized microporous membrane-well chamber system to separate the partially decellularised tracheal epithelium explants and AEC culture. The co-culture assays provided evidence of the stimulatory behaviour of AECs to enhance tracheal epithelial cell proliferation and migration during early wound repair. Factors that were secreted by AECs also markedly suppressed the production of IL-1β and IL-6 and initiated the EMT process during tracheal remodelling.
  15. Viral hepatitis in Asia-Pacific: a post-COVID-19 reset
    Wallace J, Hamid S, Mohamed R, Wong T
    Lancet Gastroenterol Hepatol, 2023 Sep;8(9):778-780.
    PMID: 37348526 DOI: 10.1016/S2468-1253(23)00161-9
  16. Fulltext Association of vaspin rs2236242 with type 2 diabetes mellitus and obesity: a meta-analysis of case-control studies
    Zain SM, Pung YF, Mohamed R
    J Diabetes Metab Disord, 2023 Jun;22(1):237-243.
    PMID: 37255815 DOI: 10.1007/s40200-022-01119-8
    BACKGROUND: Elevated circulating vaspin levels is linked with type 2 diabetes mellitus (T2DM) and obesity. The genetic basis of the association between vaspin rs2236242 and T2DM and obesity is still being investigated. We executed a meta-analysis to evaluate the magnitude of effect caused by vaspin rs2236242 on T2DM and obesity.

    METHODS: We searched Pubmed, Embase, MEDLINE, Scopus, Web of Science, and Google Scholar for relevant articles published up to 19 February 2022. Data were extracted and summary estimates of the association between vaspin rs2236242 and T2DM and obesity were assessed. Odds ratios (ORs) and confidence intervals (CIs) were used to measure the effect.

    RESULTS: This meta-analysis included 2206 cases and 2715 controls in the T2DM cohort, meanwhile 271 cases and 444 controls in the obesity cohort. The pooled estimates revealed no link between vaspin rs2236242 and T2DM, but allele-A was significantly higher in the controls of the obesity cohort, showing that this single nucleotide polymorphism (SNP) has a reduced obesity risk effect. Sensitivity analysis revealed no studies that would modify the estimates or the heterogeneity. Begg and Mazumdar's and Egger's tests indicated no substantial publication bias.

    CONCLUSION: Our meta-analysis provides evidence of significant association between vaspin rs2236242 and reduced risk of obesity but not T2DM.

    SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s40200-022-01119-8.

  17. Fulltext Understanding the knowledge, awareness, and attitudes of the public towards liver diseases in Malaysia
    Mohamed R, Yip C, Singh S
    Eur J Gastroenterol Hepatol, 2023 Jul 01;35(7):742-752.
    PMID: 37161976 DOI: 10.1097/MEG.0000000000002548
    BACKGROUND: Viral hepatitis B and C (HBV, HCV) and non-alcoholic fatty liver disease (NAFLD) are the commonest etiologies of liver-related deaths in Malaysia. Herein, this study aims to explore and understand the knowledge and attitudes of the public toward liver-related health and diseases in Malaysia.

    METHODS: A cross-sectional, self-reported, web-based questionnaire was conducted among 500 adults between February and March 2020. Questionnaire items pertained to the knowledge and attitudes toward liver-related health and diseases.

    RESULTS: Half of the respondents were aged ≥35 years and 52.0% were males. Gaps in knowledge included the lack of awareness of different types of hepatitis, including the potential transmission risks and complications of HBV and HCV. About half acknowledged liver fibrosis and cirrhosis as key determinants of liver-related disease progression. A higher proportion rightly recognized the diagnostic test for HCV (40.8%) than HBV (30.0%) despite more being aware of HBV than HCV. Less than one-third were aware of the risk factors, screening tests, and complications of NAFLD. Despite the majority (92.8%) agreeing that regular screening was important for liver health, only 67.0% attended recent health screening and one-fifth were unlikely to seek medical consultation upon exposure to viral hepatitis risk factors. Reasons for this low urgency included the perception of being healthy, cost-related concerns, and societal discrimination.

    CONCLUSION: Robust education efforts are needed to raise awareness and empower the community with knowledge of liver-related diseases, particularly viral hepatitis and NAFLD in Malaysia.

  18. Fulltext Antimicrobial susceptibility of clinical isolates of Pseudomonas aeruginosa from a Malaysian Hospital
    Pathmanathan SG, Samat NA, Mohamed R
    Malays J Med Sci, 2009 Apr;16(2):27-32.
    PMID: 22589655 MyJurnal
    Ongoing surveillance of Pseudomonas aeruginosa resistance against antimicrobial agents is fundamental to monitor trends in susceptibility patterns and to appropriately guide clinicians in choosing empirical or directed therapy. The in vitro activity level of eight antimicrobial drugs was assessed against 97 clinical isolates of P. aeruginosa collected consecutively for three months in 2007 from a Malaysian hospital. Antimicrobial susceptibility was determined using the E-test method in addition to the hospital's routine diagnostic testing by the disk diffusion method. Respiratory and wound swab isolates were the most frequently encountered isolates. The E-test and disk diffusion methods showed high concordance in determining the in vitro activity of the antimicrobial agents against the E isolates. Piperacillin-tazobactam was the most active antimicrobial agent with 91.8% susceptibility, followed by the aminoglycosides (amikacin, 86.6% and gentamicin, 84.5%), the quinolone (ciprofloxacin, 83.5%) and the beta-lactams (cefepime, 80.4%, ceftazidime, 80.4%, imipenem, 79.4% and meropenem, 77.3%). Incidence of multidrug resistance was 19.6% (19 out of 97 isolates). Periodic antibiotic resistance surveillance is fundamental to monitor changes in susceptibility patterns in a hospital setting.

    Study site: Hospital Kuala Lumpur
  19. Multi-residue analytical methodology-based liquid chromatography-time-of-flight-mass spectrometry for the analysis of pharmaceutical residues in surface water and effluents from sewage treatment plants and hospitals
    Al-Qaim FF, Abdullah MP, Othman MR, Latip J, Zakaria Z
    J Chromatogr A, 2014 Jun 6;1345:139-53.
    PMID: 24768127 DOI: 10.1016/j.chroma.2014.04.025
    An analytical method that facilitated the analysis of 11 pharmaceuticals residue (caffeine, prazosin, enalapril, carbamazepine, nifedipine, levonorgestrel, simvastatin, hydrochlorothiazide, gliclazide, diclofenac-Na, and mefenamic acid) with a single pre-treatment protocol was developed. The proposed method included an isolation and concentration procedure using solid phase extraction (Oasis HLB), a separation step using high-performance liquid chromatography, and a detection procedure that applies time-of-flight mass spectrometry. The method was validated for drinking water (DW), surface water (SW), sewage treatment plant (STP) influent and effluent, and hospital (HSP) influent and effluent. The limits of quantification were as low as 0.4, 1.6, 5, 3, 2.2 and 11 ng/L in DW, SW, HSP influent and effluent, STP effluent, and STP influent, respectively. On average, good recoveries higher than 75% were obtained for most of the target analytes in all matrices. Matrix effect was evaluated for all samples matrices. The proposed method successfully determined and quantified the target compounds in raw and treated wastewater of four STPs and three hospitals in Malaysia, as well as in two SW sites. The results showed that a number of the studied compounds pose moderate to high persistency in sewage treatment effluents as well as in the recipient rivers, namely; caffeine, simvastatin, and hydrochlorothiazide. Ten out of 11 compounds were detected and quantified in 13 sampling points. Caffeine was detected with the highest level, with concentrations reaching up to 9099 ng/L in STP influent.
  20. Association of Malaysian Helicobacter pylori virulence polymorphisms with severity of gastritis and patients' ethnicity
    Alfizah H, Ramelah M, Rizal AM, Anwar AS, Isa MR
    Helicobacter, 2012 Oct;17(5):340-9.
    PMID: 22967117 DOI: 10.1111/j.1523-5378.2012.00956.x
    Polymorphisms of Helicobacter pylori cagA and vacA genes do exist and may contribute to differences in H. pylori infection and gastroduodenal diseases among races in the Malaysian population. This study was conducted to characterize the polymorphisms in H. pylori cagA and vacA in Malaysian population.
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links