Displaying publications 61 - 80 of 95 in total

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  1. Bimakr M, Rahman RA, Taip FS, Adzahan NM, Sarker MZ, Ganjloo A
    Molecules, 2012 Oct 08;17(10):11748-62.
    PMID: 23044712 DOI: 10.3390/molecules171011748
    In the present study, ultrasound-assisted extraction of crude oil from winter melon seeds was investigated through response surface methodology (RSM). Process variables were power level (25-75%), temperature (45-55 °C) and sonication time (20-40 min). It was found that all process variables have significant (p < 0.05) effects on the response variable. A central composite design (CCD) was used to determine the optimum process conditions. Optimal conditions were identified as 65% power level, 52 °C temperature and 36 min sonication time for maximum crude yield (108.62 mg-extract/g-dried matter). The antioxidant activity, total phenolic content and fatty acid composition of extract obtained under optimized conditions were determined and compared with those of oil obtained by the Soxhlet method. It was found that crude extract yield (CEY) of ultrasound-assisted extraction was lower than that of the Soxhlet method, whereas antioxidant activity and total phenolic content of the extract obtained by ultrasound-assisted extraction were clearly higher than those of the Soxhlet extract. Furthermore, both extracts were rich in unsaturated fatty acids. The major fatty acids of the both extracts were linoleic acid and oleic acid.
  2. Bimakr M, Rahman RA, Taip FS, Adzahan NM, Sarker MZ, Ganjloo A
    Molecules, 2013 Jan 15;18(1):997-1014.
    PMID: 23322066 DOI: 10.3390/molecules18010997
    In the present study, supercritical carbon dioxide (SC-CO(2)) extraction of seed oil from winter melon (Benincasa hispida) was investigated. The effects of process variables namely pressure (150-300 bar), temperature (40-50 °C) and dynamic extraction time (60-120 min) on crude extraction yield (CEY) were studied through response surface methodology (RSM). The SC-CO(2) extraction process was modified using ethanol (99.9%) as co-solvent. Perturbation plot revealed the significant effect of all process variables on the CEY. A central composite design (CCD) was used to optimize the process conditions to achieve maximum CEY. The optimum conditions were 244 bar pressure, 46 °C temperature and 97 min dynamic extraction time. Under these optimal conditions, the CEY was predicted to be 176.30 mg-extract/g-dried sample. The validation experiment results agreed with the predicted value. The antioxidant activity and fatty acid composition of crude oil obtained under optimized conditions were determined and compared with published results using Soxhlet extraction (SE) and ultrasound assisted extraction (UAE). It was found that the antioxidant activity of the extract obtained by SC-CO(2) extraction was strongly higher than those obtained by SE and UAE. Identification of fatty acid composition using gas chromatography (GC) showed that all the extracts were rich in unsaturated fatty acids with the most being linoleic acid. In contrast, the amount of saturated fatty acids extracted by SE was higher than that extracted under optimized SC-CO(2) extraction conditions.
  3. Abdul Rahman RA, Hanapiah FA, Nikmat AW, Ismail NA, Manaf H
    Neurosciences (Riyadh), 2019 01;24(1):29-35.
    PMID: 30842397 DOI: 10.17712/nsj.2019.1.20180195
    OBJECTIVE: To investigate the effects of concurrent tasks (motor and cognitive) on postural control performance in children with traumatic brain injury (TBI) compared to typically developing (TD) control subjects.

    METHODS: Sixteen children with TBI (aged 11.63+/-1.89 years) and 22 TD controls (aged 11.41+/-2.24 years) participated in this case-control study. This study was conducted between May 2016 and March 2017. Each child performed static standing under 3 different conditions: single, concurrent motor, and concurrent cognitive task. Postural control performance measure includes sway area, anterior-posterior (AP) sway velocity, medio-lateral (ML) sway velocity, AP sway distance and ML sway distance as measured using the APDM Mobility Lab (Oregon, Portland). A repeated-measure analysis of variance was used to analyse the data.

    RESULTS: We found that children with TBI showed significantly more deterioration in postural control performance than TD children (p<0.05). Both concurrent tasks (motor and cognitive) significantly decreased postural control performance in both groups with more pronounced changes in children with TBI than that of the TD controls.

    CONCLUSION: The results demonstrated that, performing concurrent tasks (motor and cognitive) during upright standing resulted in deterioration of postural control performance. The existence of cognitive and balance impairment in children with TBI will possibly cause concurrent tasks to be more complex and demands greater attention compared to single task.

  4. Liew Y, Capule FR, Rahman RA, Nor NM, Teo R, Makmor-Bakry M
    Pharmacogenomics, 2023 Apr;24(5):247-259.
    PMID: 36999508 DOI: 10.2217/pgs-2023-0006
    Aims: To investigate the roles of MDR1 (1236C>T, 2677G>T/A, and 3435C>T) and OPRM1 (118A>G) gene polymorphisms on the anesthetic and adverse effects of propofol-remifentanil total intravenous anesthesia in pediatric surgery. Materials & methods: The genotypes were identified through Sanger sequencing. The clinical data including hemodynamics on anesthesia, postanesthesia pain and sedation score and the occurrence of adverse effects were recorded and compared against the genetic data. Results: A total of 72 pediatric patients undergoing surgery were recruited. A weak to no association was found between the genetic polymorphisms of MDR1 and OPRM1 and the anesthetic and adverse effects of propofol-remifentanil. Conclusion: Genetic polymorphisms in OPRM1, but not in MDR1, gene polymorphism, demonstrated plausible association with the effects of propofol-remifentanil.
  5. Rahman RA
    PhytoKeys, 2019;118:65-73.
    PMID: 30863195 DOI: 10.3897/phytokeys.118.32186
    A new species, Microchiritahairulii Rafidah (Gesneriaceae) from limestone hills in Perlis, Peninsular Malaysia, is described and illustrated. Diagnostic characters, description, detailed illustrations, geographical distribution, regional provisional conservation status assessment (Endangered) and ecological observations of the new taxon, as well as an updated key to Microchirita species in Peninsular Malaysia, are provided.
  6. Barber CV, Yo JH, Rahman RA, Wallace EM, Palmer KR, Marshall SA
    Placenta, 2023 May;136:35-41.
    PMID: 37028223 DOI: 10.1016/j.placenta.2023.03.008
    Activin A is a two-subunit protein belonging to the transforming growth factor β superfamily. First discovered almost three decades ago, it has since been implicated in diverse physiological roles, ranging from wound repair to reproduction. After 30 years of research, altered activin A levels are now understood to be associated with the development of various diseases, making activin A a potential therapeutic target. In pregnancy, the placenta and fetal membranes are major producers of activin A, with significantly enhanced serum concentrations now recognised as a contributor to numerous gestational disorders. Evidence now suggests that circulating levels of activin A may be clinically relevant in the early detection of pregnancy complications, including miscarriage and preeclampsia. This review aims to summarise our current understanding of activin A as a potential diagnostic marker in common pregnancy pathologies.
  7. Senin A, Noordin NM, Sani JAM, Mahat D, Donadel M, Scobie HM, et al.
    PLoS One, 2024;19(3):e0298730.
    PMID: 38483868 DOI: 10.1371/journal.pone.0298730
    INTRODUCTION: A lateral flow rapid diagnostic test (RDT) enables detection of measles specific immunoglobulin M (IgM) antibody in serum, capillary blood, and oral fluid with accuracy consistent with enzyme immunoassay (EIA). The objectives of the study were: 1) to assess measles RDT inter-reader agreement between two clinic staff; 2) to assess the sensitivity and specificity of the measles RDT relative to standard surveillance testing in a low transmission setting; 3) to evaluate the knowledge, attitudes, and practices of staff in clinics using the RDT; and 4) to assess the impact of RDT testing on the measles public health response in Malaysia.

    MATERIALS AND METHODS: The clinic-based prospective evaluation included all suspected measles cases captured by routine measles surveillance at 34 purposely selected clinics in 15 health districts in Malaysia between September 2019 and June 2020, following day-long regional trainings on RDT use. Following informed consent, four specimens were collected from each suspected case, including those routinely collected for standard surveillance [serum for EIA and throat swabs for quantitative reverse transcriptase polymerase chain reaction (RT-qPCR)] together with capillary blood and oral fluid tested with RDTs during the study. RDT impact was evaluated by comparing the rapidity of measles public health response between the pre-RDT implementation (December 2018 to August 2019) and RDT implementation periods (September 2019 to June 2020). To assess knowledge, attitudes, and practices of RDT use, staff involved in the public health management of measles at the selected sites were surveyed.

    RESULTS: Among the 436 suspect cases, agreement of direct visual readings of measles RDT devices between two health clinic staff was 99% for capillary blood (k = 0.94) and 97% for oral fluid (k = 0.90) specimens. Of the total, 45 (10%) were positive by measles IgM EIA (n = 44, including five also positive by RT-qPCR) or RT-qPCR only (n = 1), and 38 were positive by RDT (using either capillary blood or oral fluid). Using measles IgM EIA or RT-qPCR as reference, RDT sensitivity using capillary blood was 43% (95% CI: 30%-58%) and specificity was 98% (95% CI: 96%-99%); using oral fluid, sensitivity (26%, 95% CI: 15%-40%) and specificity (97%, 95% CI: 94%-98%) were lower. Nine months after training, RDT knowledge was high among staff involved with the public health management of measles (average quiz score of 80%) and was highest among those who received formal training (88%), followed by those trained during supervisory visits (83%). During the RDT implementation period, the number of days from case confirmation until initiation of public response decreased by about 5 days.

    CONCLUSION: The measles IgM RDT shows >95% inter-reader agreement, high retention of RDT knowledge, and a more rapid public health response. However, despite ≥95% RDT specificity using capillary blood or oral fluid, RDT sensitivity was <45%. Higher-powered studies using highly specific IgM assays and systematic RT-qPCR for case confirmation are needed to establish the role of RDT in measles elimination settings.

  8. Mohd Pisal MH, Osman AF, Jin TS, Rahman RA, Alrashdi AA, Masa A
    Polymers (Basel), 2021 Feb 17;13(4).
    PMID: 33671304 DOI: 10.3390/polym13040600
    Carbonized natural filler can offer the production of low cost composites with an eco-friendliness value. The evolving field of electronics encourages the exploration of more functions and potential for carbonized natural filler, such as by modifying its surface chemistry. In this work, we have performed surface modification on carbonized wood fiber (CWF) prior to it being used as filler in the ethylene vinyl acetate (EVA) composite system. Zinc chloride (ZnCl2) with various contents (2 to 8 wt%) was used to surface modify the CWF and the effects of ZnCl2 composition on the surface morphology and chemistry of the CWF filler were investigated. Furthermore, the absorptive, mechanical, thermal, and electrical properties of the EVA composites containing CWF-ZnCl2 were also analyzed. SEM images indicated changes in the morphology of the CWF while FTIR analysis proved the presence of ZnCl2 functional groups in the CWF. EVA composites incorporating the CWF-ZnCl2 showed superior mechanical, thermal and electrical properties compared to the ones containing the CWF. The optimum content of ZnCl2 was found to be 6 wt%. Surface modification raised the electrical conductivity of the EVA/CWF composite through the development of conductive deposits in the porous structure of the CWF as a channel for ionic and electronic transfer between the CWF and EVA matrix.
  9. Abdul Rahman RA, Rafi F, Hanapiah FA, Nikmat AW, Ismail NA, Manaf H
    Rehabil Res Pract, 2018;2018:2071726.
    PMID: 30402290 DOI: 10.1155/2018/2071726
    Background: Tasks requiring simultaneous mobility and cognition (dual tasks) have been associated with incidence of falls. Although these deficits have been documented in individuals with neurologic disorder, the effect of dual task in children with traumatic brain injury has not been fully explored.

    Objective: To investigate the effect of dual-task (dual-motor and dual-cognitive task) conditions on spatiotemporal gait parameters during timed up and go test in children with traumatic brain injury.

    Methods and Material: A total of 14 children with traumatic brain injury and 21 typically developing children participated in this case-control study. Functional balance was assessed before the actual testing to predict the risk of falls. Timed up and go test was performed under single-task and dual-task (dual-motor and dual-cognitive task) conditions. Spatiotemporal gait parameters were determined using the APDM Mobility Lab system. The descriptive statistics and t-test were used to analyze demographic characteristics and repeated measure ANOVA test was used to analyze the gait parameters.

    Results: Under dual-task (dual-motor and dual-cognitive task) conditions during the timed up and go test, gait performance significantly deteriorated. Furthermore, the total time to complete the timed up and go test, stride velocity, cadence, and step time during turning were significantly different between children with traumatic brain injury and typically developing children.

    Conclusions: These findings suggest that gait parameters were compromised under dual-task conditions in children with traumatic brain injury. Dual-task conditions may become a component of gait training to ensure a complete and comprehensive rehabilitation program.

  10. Sulaiman AS, Ahmad S, Ismail NA, Rahman RA, Jamil MA, Mohd Dali AZ
    Saudi Med J, 2013 Aug;34(8):819-23.
    PMID: 23974453
    To evaluate the prevalence of obstetrical anal sphincter injuries (OASIS), which include third and fourth degree perineal tears in primigravida in routine versus selective mediolateral episiotomy. Secondly, to determine the rate of episiotomy in local settings.
  11. Chai WL, Ngeow WC, Ramli R, Rahman RA
    Singapore Dent J, 2006 Dec;28(1):4-6.
    PMID: 17378334
    Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Where possible, pretreatment dental assessment shall be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally for radiation therapy. Because of this, they succumb to complicated oral complications after radiation therapy. The management of xerostomia has been reviewed in Part I of this series. In this article, the management of dental caries, a sequalae of xerostomia following radiation therapy is reviewed.
  12. Ngeow WC, Chai WL, Rahman RA, Ramli R
    Singapore Dent J, 2006 Dec;28(1):1-3.
    PMID: 17378333
    Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Where possible, pretreatment dental assessment shall be provided for these patients before they receive radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally for radiation therapy. Because of this, they succumb to complicated oral adverse effects after radiation therapy. Part I of this series reviews the management of xerostomia. The management of the effect of xerostomia to the dentition/oral cavity is discussed in Part II.
  13. Ramli R, Ngeow WC, Rahman RA, Chai WL
    Singapore Dent J, 2006 Dec;28(1):11-5.
    PMID: 17378336
    Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Pretreatment dental assessment should be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally and, as a result, they succumb to complicated oral adverse effects after radiation therapy. Osteoradionecrosis (ORN) is a severe debilitating condition that impairs healing due to reduction in vascularity and osteocyte population in the affected bone. This article reviews methods of treatment used to treat ORN such as antibiotics, hyperbaric oxygen therapy, therapeutic ultrasound, surgery, and other modalities.
  14. Rahman RA, Ngeow WC, Chai WL, Ramli R
    Singapore Dent J, 2006 Dec;28(1):7-10.
    PMID: 17378335
    Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Pretreatment dental assessment should be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally and, as a result, they succumb to complicated oral adverse effects after radiation therapy. The management of radiation-induced caries, a sequelae of xerostomia has been reviewed in Part II of this series. In this article, the management of difficulty with dentures, another sequelae of xerostomia following radiation therapy is reviewed.
  15. Ngeow WC, Chai WL, Ramli R, Rahman RA
    Singapore Dent J, 2006 Dec;28(1):19-21.
    PMID: 17378338
    Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Where possible, pretreatment dental assessment shall be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally for radiation therapy. Because of this, they succumb to complicated oral adverse effects after radiation therapy. The last part of this series reviews the opportunistic infections that can occur to the perioral structure. Their management is briefly discussed.
  16. Ngeow WC, Chai WL, Rahman RA, Ramli R
    Singapore Dent J, 2006 Dec;28(1):16-8.
    PMID: 17378337
    Head and neck cancer is becoming a more recognizable pathology to the general population and dentists. The modes of treatment include surgery and/or radiation therapy. Where possible, pretreatment dental assessment shall be provided for these patients before they undergo radiation therapy. There are occasions, however, whereby head and neck cancer patients are not prepared optimally for radiation therapy. Because of this, they succumb to complicated oral adverse effects after radiation therapy. The second last part of this series reviews and discusses the management of complication that commonly occur to the oral mucosa, i.e. mucositis.
  17. Lim TO, Ngah BA, Rahman RA, Suppiah A, Ismail F, Chako P, et al.
    Singapore Med J, 1992 Feb;33(1):63-6.
    PMID: 1598610
    Poor compliance with drug treatment is a barrier to effective management of hypertension. Drug compliance behaviour of 168 patients were studied, their drug compliance was measured by the pill-counting method. The prevalence of non-compliance with medication was 26%. Thirteen variables were examined for their association with compliance; these were age, sex, duration of hypertension since diagnosis, adequacy of blood pressure control, complexity of drug regimen and side-effect of drug, history of previous admission for hypertension related reason, patient's knowledge of hypertensive complications, patient's belief that drug was 'panas' or 'san', previous use of traditional treatment for hypertension, patient's fatalistic attitude, their social support and satisfaction with the health services. None of these variables were significantly related to compliance (p greater than 0.05) except adequacy of blood pressure control. The performance of patient self-report was compared with pill-count as a measure of drug compliance; it was poorly predictive of non-compliance (sensitivity = 71%, specificity = 50%). An inverse relationship was found between non-compliance with medication and patient subsequent drop-out rate. Patients who were compliant were more likely to remain on treatment and vice versa. As a measure of drug compliance, detection of drop-out compared well with pill-count (sensitivity 97%, specificity 66%, positive predictive value 89%, negative predictive value 88%).
    Study site: outpatient clinic, Hospital Mentakab, Pahang, Malaysia
  18. Rahman RA, Ahmad A, Rahman ZA, Mokhtar KI, Lah NA, Zilfalil BA, et al.
    Cleft Palate Craniofac J, 2008 Nov;45(6):583-6.
    PMID: 18956930 DOI: 10.1597/07-020.1
    To determine the frequency of the transforming growth factor-alpha (TGFalpha) Taq1 polymorphism in nonsyndromic cleft lip with or without cleft palate (CL+/-P) and cleft palate only (CP) in Kelantan, Malaysia.
  19. Singh J, Rahman RA, Rajion ZA, Abdullah J, Mohamad I
    J Craniofac Surg, 2017 Jan;28(1):e64-e70.
    PMID: 27922969 DOI: 10.1097/SCS.0000000000003218
    INTRODUCTION: The human orbit is a complex anatomic region, which plays predominant role in the evaluation of craniofacial complex. A thorough understanding of the relationship of the distance from orbital rim to the important vital structures of the orbital apex is required for the surgeon to perform safe and effective surgery.

    OBJECTIVES: To evaluate and compare the depth and distances from various points of the orbital rim to the fissures and foramina of the orbital apex between genders in the local population.

    METHODOLOGY: Linear measurements were conducted on 60 orbits from 30 patients who had undergone head computed tomography scan. These measurements were done utilizing the multiplanar reconstruction modes on computed tomography images with minimum slice thickness of 1 mm.

    RESULTS: Males have statistically significant larger orbits than females with higher mean measurements in all parameters, except for the distance from posterior ethmoidal foramen to the optic canal which was the same. However, there were no significant differences in all parameters between the right and left orbits.

    CONCLUSION: This study provides the absolute limit of safe internal orbital dissection in respect to the local population. Despite males having larger orbits than females, it is clinically negligible.

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