Displaying publications 141 - 160 of 282 in total

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  1. Ahmad S, Ismail AI, Zim MAM, Ismail NE
    Front Public Health, 2019;7:420.
    PMID: 32039131 DOI: 10.3389/fpubh.2019.00420
    Purpose: The elusive goal of asthma management guidelines is to achieve and maintain good asthma control in asthmatic patients. Against a background of long-term respiratory limitations when living with asthma, stigma and low self-esteem have also been identified as the social phenomenon among adult asthmatics. This study aimed to assess the levels of self-stigma, self-esteem, and asthma control, and to investigate the impact of self-stigma and self-esteem as psychosocial factors on asthma control in Malaysian adults living with asthma.
    Materials and Methods: In this multicenter cross-sectional study, post-ethics approval and patients' consents, 152 stable asthmatic patients (aged > 18 years old; nil cognitive disability; not diagnosed with other respiratory diseases) were recruited from four respiratory clinics in Selangor, Malaysia. The patients' socio-demographic, medical, and psychosocial (self-stigma and self-esteem) data were recorded in a pre-validated, self-designed questionnaire. All data were analyzed descriptively and inferentially (independent t-test/one-way ANOVA, and multiple linear regression) using the Statistical Package for Social Sciences (SPSS®).
    Results: The enrolled patients showed moderate levels of self-stigma (62.12 ± 6.44) and self-esteem (29.31 ± 3.29), and not well-controlled asthma (17.58 ± 3.99). The number of patients' visits to emergency rooms because of asthma [CI (-1.199, 0.317), p < 0.001] was the significant predictor to asthma control among all selected study variables from socio-demographic and medical data. Moreover, from psychosocial factors both self-stigma [CI (-0.367, 0.190), p < 0.001], and self-esteem [CI (-0.007, 0.033), p = 0.041] found to be the significant predictors of asthma control.
    Conclusion: The preliminary evidences presented in this study found that frequent emergency room visits, high self-stigma and low self-esteem in asthma patients becomes more apparent with poor asthma control. Educational interventions to reduce patients' self-stigma and improve self-esteem are needed to achieve optimal control of asthma.
    Study site: Four respiratory clinics in Selangor, Malaysia (UiTM Respiratory specialist Clinic, Hospital Selayang and Hospital Sungai Buloh)
  2. Azid N.A.,, Md Sani M, Zamry A.A, Ahmad, S, Mohd Ashari N.S., Tan H.T.T., et al.
    MyJurnal
    Total immunoglobulin E (IgE) has been an indicator for early diagnosis of allergic diseases due the important role of IgE in the sensitization towards allergens. Although total IgE is a common diagnostic test that screens for possible allergic diseases, reports are still lacking on the profile of total IgE levels of allergic patients from the north-east region of Peninsular Malaysia. Hence, this study aimed to investigate the association of total IgE levels with clinico-demographic parameters and whether increasing total IgE levels were associated with certain allergic manifestations in this study cohort. A local cohort of allergic patients (n=71) diagnosed in between 2009 and 2016 in Hospital Universiti Sains Malaysia (HUSM) were evaluated for the relevance of total IgE levels in allergy diagnosis. Our study did not demonstrate significant association between total IgE with age (p=0.75) or gender (p=0.65). However, we showed that elevated total IgE levels were associated with disease severity. Our data suggests that increasing total IgE levels beyond the conventional cutoff used to define abnormal IgE levels were more commonly associated with patients presenting allergic asthma and skin allergy manifestations. Total IgE level is a useful indicator for diagnosis of allergic diseases. Although total IgE level might not be sufficient to confirm the sensitization status of an individual, it may reflect the severity of the allergic disease suffered and it has a high correlation with positive sIgE values.
  3. Ismail NE, Jimam NS, Dapar MLP, Ahmad S
    Front Pharmacol, 2019;10:1521.
    PMID: 31998125 DOI: 10.3389/fphar.2019.01521
    Background: This study assessed the validity and reliability of healthcare workers' knowledge, attitudes, and practices instrument for uncomplicated malaria (HKAPIUM) for evaluation of healthcare workers' knowledge, attitudes, and practices (KAP) on uncomplicated malaria management in primary healthcare (PHC) facilities in Plateau state, Nigeria. Methods: Relevant variables from literature, malaria treatment guidelines for Nigeria, and World Health Organization (WHO) were used to generate and present the items for the draft HKAPIUM scale, which was first screened by six experts before administered to 121 respondents who filled and returned immediately. The data were sorted and analyzed using Rasch measurement model (Bond & Fox software®). Results: The outcome of the initial screening showed high items content validity indices (I-CVI) (0.83-1.00) and high scale-CVI (S-CVI) {universal agreement (UA) within the experts (S-CVI/UA) (0.67-0.89) and the average CVI [S-CVI/Ave (0.94-0.98)]} for relevance, clarity, simplicity, and comprehensiveness. The Rasch analysis outputs showed good items' reliability for the three factors (KAP) > 0.9 with high separation index values of > 2.0; however person reliability were poor (< 0.6) which were confirmed by their low separation values. Goodness of fit statistics indicated nine items not fitting the model based on the suggested fit index values of 0.6 to 1.5, and ± 2 for mean square (MNSQ) and standardized Z-score (Zstds) respectively, and 0.3 to 0.7 for "point-measure correlation coefficients" (PTMEA Corr). Deletion of misfit items resulted in the items and persons' reliabilities falling above the minimum accepted limit of 0.6, with their separation values were all in the range of 1 and 2 which were acceptable. Similarly, fit index values for MNSQ infit and outfit, and Zstd parameters items in the new scale were all within the acceptable range of 0.6 to 1.5, and ±2 respectively, in addition to the positive PTMEA Corr as further confirmation of the items' fitness to the model. Conclusion: The reduction of 27-items draft HKAPIUM scale to 18 items was successful with good reliability and fitness to the model.
  4. Edling CE, Fazmin IT, Chadda KR, Ahmad S, Valli H, Huang CL, et al.
    Front Physiol, 2019;10:497.
    PMID: 31068841 DOI: 10.3389/fphys.2019.00497
    Background: Deficiencies in the transcriptional co-activator, peroxisome proliferative activated receptor, gamma, coactivator-1β are implicated in deficient mitochondrial function. The latter accompanies clinical conditions including aging, physical inactivity, obesity, and diabetes. Recent electrophysiological studies reported that Pgc-1β-/- mice recapitulate clinical age-dependent atrial pro-arrhythmic phenotypes. They implicated impaired chronotropic responses to adrenergic challenge, compromised action potential (AP) generation and conduction despite normal AP recovery timecourses and background resting potentials, altered intracellular Ca2+ homeostasis, and fibrotic change in the observed arrhythmogenicity.

    Objective: We explored the extent to which these age-dependent physiological changes correlated with alterations in gene transcription in murine Pgc-1β-/- atria.

    Methods and Results: RNA isolated from murine atrial tissue samples from young (12-16 weeks) and aged (>52 weeks of age), wild type (WT) and Pgc-1β-/- mice were studied by pre-probed quantitative PCR array cards. We examined genes encoding sixty ion channels and other strategic atrial electrophysiological proteins. Pgc-1β-/- genotype independently reduced gene transcription underlying Na+-K+-ATPase, sarcoplasmic reticular Ca2+-ATPase, background K+ channel and cholinergic receptor function. Age independently decreased Na+-K+-ATPase and fibrotic markers. Both factors interacted to alter Hcn4 channel activity underlying atrial automaticity. However, neither factor, whether independently or interactively, affected transcription of cardiac Na+, voltage-dependent K+ channels, surface or intracellular Ca2+ channels. Nor were gap junction channels, β-adrenergic receptors or transforming growth factor-β affected.

    Conclusion: These findings limit the possible roles of gene transcriptional changes in previously reported age-dependent pro-arrhythmic electrophysiologial changes observed in Pgc-1β-/- atria to an altered Ca2+-ATPase (Atp2a2) expression. This directly parallels previously reported arrhythmic mechanism associated with p21-activated kinase type 1 deficiency. This could add to contributions from the direct physiological outcomes of mitochondrial dysfunction, whether through reactive oxygen species (ROS) production or altered Ca2+ homeostasis.

  5. Ali Y, Alqudah A, Ahmad S, Abd Hamid S, Farooq U
    Des Monomers Polym, 2019;22(1):91-97.
    PMID: 31007637 DOI: 10.1080/15685551.2019.1591681
    Targeted drug delivery system improves the efficiency and safety of the therapeutic agents by managing the pharmacokinetics and pharmacodynamics of drugs. Currently, numerous drug carrier systems have been developed with different sizes, architectures and characteristics surface properties. Among different systems, macromolecules have a wide range of applications in targeted drug delivery system. The optimal drug loading potential, smooth drug releasing ability and biocompatibility are the distinguishing features that ensure the drugs delivery ability of macromolecules. This review briefly introduces some of the most commonly studied macromolecules which have been recommended as drugs delivery vehicles.
  6. Halim AS, Nor FM, Mat Saad AZ, Mohd Nasir NA, Norsa'adah B, Ujang Z
    J Taibah Univ Med Sci, 2018 Dec;13(6):512-520.
    PMID: 31435371 DOI: 10.1016/j.jtumed.2018.10.004
    Objectives: Chitosan, the N-deacetylated derivative of chitin, has useful biological properties that promote haemostasis, analgesia, wound healing, and scar reduction; chitosan is bacteriostatic, biocompatible, and biodegradable. This study determined the efficacy of chitosan derivative film as a superficial wound dressing.

    Methods: This multicentre randomised controlled trial included 244 patients, of whom 86 were treated with chitosan derivative film and 84 with hydrocolloid. The percentage of epithelisation, as well as patient comfort, clinical signs, and patient convenience in application and removal of the dressings were assessed.

    Results: The primary outcome of this study was the percentage of epithelisation. Except for race (p = 0.04), there were no significant differences between groups in sex, age, antibiotic usage, or initial wound size (p > 0.05). There was no significant difference in the mean epithelisation percentage between groups (p = 0.29). Patients using chitosan derivative film experienced more pain during removal of dressing than those in the hydrocolloid group (p = 0.007). The chitosan derivative film group showed less exudate (p = 0.036) and less odour (p = 0.024) than the control group. Furthermore, there were no significant differences between groups in terms of adherence, ease of removal, wound drainage, erythema, itchiness, pain, and tenderness. No oedema or localised warmth was observed during the study.

    Conclusion: This study concluded that chitosan derivative film is equivalent to hydrocolloid dressing and can be an option in the management of superficial and abrasion wounds.

    Clinical trial No: NMRR-11-948-10565.

  7. Ahmad S, Zaib S, Jalil S, Shafiq M, Ahmad M, Sultan S, et al.
    Bioorg Chem, 2018 10;80:498-510.
    PMID: 29996111 DOI: 10.1016/j.bioorg.2018.04.012
    In this research work, we report the synthesis and biological evaluation of two new series of 1-benzyl-4-(benzylidenehydrazono)-3,4-dihydro-1H-benzo[c] [1,2]thiazine 2,2-dioxides and 1-benzyl-4-((1-phenylethylidene)hydrazono)-3,4-dihydro-1H-benzo[c][1,2]thiazine 2,2-dioxides. The synthetic plan involves the mesylation of methyl anthranilate with subsequent N-benzylation of the product. The methyl 2-(N-benzylmethylsulfonamido)benzoate was subjected to cyclization reaction in the presence of sodium hydride to obtain 1-benzyl-1H-benzo[c][1,2]thiazin-4(3H)-one 2,2-dioxide which was treated with hydrazine hydrate to get corresponding hydrazone precursor. Finally, the titled compounds were obtained by reaction of hydrazone with various substituted aldehydes and ketones. The synthesized derivatives were subjected to carry out their inhibition activities against monoamine oxidases along with modelling investigations to evaluate their binding interactions and dynamic stability during the docking studies. The inhibition profile of potent compounds was found as competitive for both the isozymes. The compounds were more selective inhibitors of MAO-A as compared to MAO-B. Moreover, drug likeness profile of the derivatives was evaluated to have an additional insight into the physicochemical properties. The molecular dynamic simulations predicted the behaviour of amino acids with the active site residues.
  8. Ahmad H, Ahmad S, Ali M, Latif A, Shah SAA, Naz H, et al.
    Bioorg Chem, 2018 08;78:427-435.
    PMID: 29698893 DOI: 10.1016/j.bioorg.2018.04.008
    Three new norditerpenoids alkaloids, 1β-hydroxy,14β-acetyl condelphine (1), jadwarine-A (2), jadwarine-B (3) along with two known alkaloids isotalatizidine hydrate (4) and dihydropentagynine (5) were isolated from medicinal plant Delphinium denudatum. The structures of natural products 1-5 were established on the basis of HR-EIMS, 1H and 13C NMR (1D & 2D) spectroscopic data as well as by comparison from literature data. The structures of compound 1 and 4 were also confirmed by single crystal X-ray diffraction studies. In-vitro AChE and BChE enzyme inhibitory activities of compounds 1-5 and molecular docking studies were performed to investigate the possible molecular inhibitory mechanism of the isolated natural products. Compound 2, 4 and 5 showed competitive inhibitory effects by inhibiting AChE and BChE, respectively, while 1 and 3 showed non-competitive inhibition. This work is the first report that provides a supporting evidence about the use of constituents of Delphinium denudatum in cerebral dementia and Alzheimer diseases.
  9. Santhanam RK, Fakurazi S, Ahmad S, Abas F, Ismail IS, Rukayadi Y, et al.
    Phytother Res, 2018 Aug;32(8):1608-1616.
    PMID: 29672974 DOI: 10.1002/ptr.6092
    The antiphoto aging property of Zanthoxylum rhetsa obtained from Pangkor Island, Malaysia, was evaluated. Solvent fractions of different polarity obtained from the methanolic extract of the bark material were initially tested for anticollagenase and antielastase activities. The ethyl acetate fraction showed bioactivity against the protease enzymes. Hence, it was subjected to further purification via column chromatography, to yield a major constituent, hesperidin. Subsequently, the ethyl acetate fraction and hesperidin were tested for their effects against UVB-induced cytotoxicity and expressions of inflammatory cytokines (IL-6, IL-1β, and TNF-α), NF-κB, and MMPs (MMP1, 3, and 9) in human dermal fibroblasts (HDF). Both fraction and pure compound prevented UVB-induced cytotoxicity in HDF cells, in a dose dependent manner. Moreover, the ethyl acetate fraction inhibited the increase of pro-inflammatory cytokines induced by UVB to a level similar to the control (without UV treatment). Additionally, the fraction significantly inhibited the expressions of NF-κB, MMP 1, MMP 3, and MMP 9 in HDF cells treated with UVB. Similar effects were observed with hesperidin. The results obtained suggested that the ethyl acetate fraction of Z. rhetsa and its bioactive constituent, hesperidin, have the potential to be used as active ingredients in sunscreen and antiphoto aging formulations.
  10. Razali NA, Nazarudin NA, Lai KS, Abas F, Ahmad S
    BMC Complement Altern Med, 2018 Jul 16;18(1):217.
    PMID: 30012134 DOI: 10.1186/s12906-018-2223-8
    BACKGROUND: Histamine is a well-known mediator involved in skin allergic responses through up-regulation of pro-inflammatory cytokines. Antihistamines remain the mainstay of allergy treatment, but they were found limited in efficacy and associated with several common side effects. Therefore, alternative therapeutic preferences are derived from natural products in an effort to provide safe yet reliable anti-inflammatory agents. Curcumin and their derivatives are among compounds of interest in natural product research due to numerous pharmacological benefits including anti-inflammatory activities. Here, we investigate the effects of chemically synthesized curcumin derivative, 2,6-bis(2-fluorobenzylidene)cyclohexanone (MS65), in reducing cytokine production in histamine-induced HaCaT cells.

    METHODS: Interleukin (IL)-6 cytokine production in histamine-induced HaCaT cells were measured using enzyme-linked immunosorbent assay (ELISA) and cytotoxicity effects were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Real-time polymerase chain reaction (RT-qPCR) was carried out to determine the inhibitory effects of MS65 on nuclear factor-kappa B (NF-κB) and mitogen activated protein kinase (MAPK) pathways.

    RESULTS: Histamine enhanced IL-6 production in HaCaT cells, with the highest production of IL-6 at 97.41 ± 2.33 pg/mL after 24 h of exposure. MS65 demonstrated a promising anti-inflammatory activity by inhibiting IL-6 production with half maximal inhibitory concentration (IC50) value of 4.91 ± 2.50 μM and median lethal concentration (LC50) value of 28.82 ± 7.56 μM. In gene expression level, we found that MS65 inhibits NF-κB and MAPK pathways through suppression of IKK/IκB/NFκB and c-Raf/MEK/ERK inflammatory cascades.

    CONCLUSION: Taken together, our results suggest that MS65 could be used as a lead compound on developing new medicinal agent for the treatment of allergic skin diseases.

  11. Ahmad S, Valli H, Chadda KR, Cranley J, Jeevaratnam K, Huang CL
    Mech Ageing Dev, 2018 Jul;173:92-103.
    PMID: 29763629 DOI: 10.1016/j.mad.2018.05.004
    INTRODUCTION: Ageing and age-related bioenergetic conditions including obesity, diabetes mellitus and heart failure constitute clinical ventricular arrhythmic risk factors.

    MATERIALS AND METHODS: Pro-arrhythmic properties in electrocardiographic and intracellular recordings were compared in young and aged, peroxisome proliferator-activated receptor-γ coactivator-1β knockout (Pgc-1β-/-) and wild type (WT), Langendorff-perfused murine hearts, during regular and programmed stimulation (PES), comparing results by two-way ANOVA.

    RESULTS AND DISCUSSION: Young and aged Pgc-1β-/- showed higher frequencies and durations of arrhythmic episodes through wider PES coupling-interval ranges than WT. Both young and old, regularly-paced, Pgc-1β-/- hearts showed slowed maximum action potential (AP) upstrokes, (dV/dt)max (∼157 vs. 120-130 V s-1), prolonged AP latencies (by ∼20%) and shortened refractory periods (∼58 vs. 51 ms) but similar AP durations (∼50 ms at 90% recovery) compared to WT. However, Pgc-1β-/- genotype and age each influenced extrasystolic AP latencies during PES. Young and aged WT ventricles displayed distinct, but Pgc-1β-/- ventricles displayed similar dependences of AP latency upon (dV/dt)max resembling aged WT. They also independently increased myocardial fibrosis. AP wavelengths combining activation and recovery terms paralleled contrasting arrhythmic incidences in Pgc-1β-/- and WT hearts. Mitochondrial dysfunction thus causes pro-arrhythmic Pgc-1β-/- phenotypes by altering AP conduction through reducing (dV/dt)max and causing age-dependent fibrotic change.

  12. Fadzil F, Shamsuddin K, Wan Puteh SE, Mohd Tamil A, Ahmad S, Abdul Hayi NS, et al.
    Obes Res Clin Pract, 2018 06 28;12(6):493-499.
    PMID: 29960869 DOI: 10.1016/j.orcp.2018.06.003
    BACKGROUND: Women of childbearing age are predisposed to becoming overweight or obese. This study determines the mean, prevalence and factors associated with 6 months postpartum weight retention among urban Malaysian mothers.

    METHODS: A prospective cohort study was conducted at baseline (after delivery), 2, 4 and 6 months postpartum. From 638 eligible mothers initially recruited, 420 completed until 6 months. Dependent variable was weight retention, defined as difference between weight at 6 months postpartum and pre-pregnancy weight, and weight retention ≥5kg was considered excessive. Independent variables included socio-demographic, history of pregnancy and delivery, lifestyle, practices and traditional postpartum practices.

    RESULTS: Average age was 29.61±4.71years, majority (83.3%) were Malays, 58.8% (low education), 70.0% (employed), 65.2% (middle income family), 33.8% (primiparous) and 66.7% (normal/instrumental delivery). Average gestational weight gain was 12.90±5.18kg. Mean postpartum weight retention was 3.12±4.76kg, 33.8% retaining ≥5kg. Bivariable analysis showed low income, primiparity, gestational weight gain ≥12kg, less active physically, higher energy, protein, carbohydrate and fat intake in diet, never using hot stone compression and not continuing breastfeeding were significantly associated with higher 6 months postpartum weight retention. From multivariable linear regression analysis, less active physically, higher energy intake in diet, gestational weight gain ≥12kg, not continuing breastfeeding 6 months postpartum and never using hot stone compression could explain 55.1% variation in 6 months postpartum weight retention.

    CONCLUSION: Women need to control gestational weight gain, remain physically active, reduce energy intake, breastfeed for at least 6 months and use hot stone compression to prevent high postpartum weight retention.

  13. Nurulain MZ, Ahmad S, Asma H, Abdul M
    Med J Malaysia, 2018 04;73(2):67-72.
    PMID: 29703868
    OBJECTIVE: Cataract is the leading cause of blindness in Malaysia. There is an alarming backlog of cataract extraction surgery as the majority believes they did not require surgery. This study aimed to explore the barriers at the primary care level to cataract surgery from the perspective of patients with severe cataract blindness.

    METHODS: Eleven participants were involved in this qualitative research which utilised the interpretative phenomenological analysis approach more renowned in health psychology research. All interviews conducted at their home. The interviews were recorded, typed verbatim, and the transcripts were analysed using NVivo software version 8.0.

    RESULTS: The main barriers identified at the primary care level were 1) nondisclosure of their visual problems originated from their belated needs for better sight, delayed awareness of their visual status and social stigma and 2) patient-provider-related issues namely miscommunication and delayed referral. The first main theme explains their belief for not requiring surgery. This has led to their delayed awareness and impeded disclosure of their visual problems to family members or primary care providers. The second main theme reflects the provider-patient-related issues which retarded cataract detection and referral process required for earlier cataract extraction surgery.

    CONCLUSION: Thus, the appropriate approach targeting these specific barriers at primary care level will be able to detect, motivate and assist patients for early uptake of cataract extraction surgery to improve their vision and prevent severe blindness.

  14. Valli H, Ahmad S, Sriharan S, Dean LD, Grace AA, Jeevaratnam K, et al.
    Clin Exp Pharmacol Physiol, 2018 03;45(3):278-292.
    PMID: 29027245 DOI: 10.1111/1440-1681.12870
    Acute RyR2 activation by exchange protein directly activated by cAMP (Epac) reversibly perturbs myocyte Ca2+ homeostasis, slows myocardial action potential conduction, and exerts pro-arrhythmic effects. Loose patch-clamp studies, preserving in vivo extracellular and intracellular conditions, investigated Na+ current in intact cardiomyocytes in murine atrial and ventricular preparations following Epac activation. Depolarising steps to varying test voltages activated typical voltage-dependent Na+ currents. Plots of peak current against depolarisation from resting potential gave pretreatment maximum atrial and ventricular currents of -20.23 ± 1.48 (17) and -29.8 ± 2.4 (10) pA/μm2 (mean ± SEM [n]). Challenge by 8-CPT (1 μmol/L) reduced these currents to -11.21 ± 0.91 (12) (P  .05). Assessment of the inactivation that followed by applying subsequent steps to a fixed voltage 100 mV positive to resting potential gave concordant results. Half-maximal inactivation voltages and steepness factors, and time constants for Na+ current recovery from inactivation in double-pulse experiments, were similar through all the pharmacological conditions. Intracellular sharp microelectrode membrane potential recordings in intact Langendorff-perfused preparations demonstrated concordant variations in maximum rates of atrial and ventricular action potential upstroke, (dV/dt)max . We thus demonstrate an acute, reversible, Na+ channel inhibition offering a possible mechanism for previously reported pro-arrhythmic slowing of AP propagation following modifications of Ca2+ homeostasis, complementing earlier findings from chronic alterations in Ca2+ homeostasis in genetically-modified RyR2-P2328S hearts.
  15. Ahmad S, Valli H, Salvage SC, Grace AA, Jeevaratnam K, Huang CL
    Clin Exp Pharmacol Physiol, 2018 02;45(2):174-186.
    PMID: 28949414 DOI: 10.1111/1440-1681.12863
    Increasing evidence implicates chronic energetic dysfunction in human cardiac arrhythmias. Mitochondrial impairment through Pgc-1β knockout is known to produce a murine arrhythmic phenotype. However, the cumulative effect of this with advancing age and its electrocardiographic basis have not been previously studied. Young (12-16 weeks) and aged (>52 weeks), wild type (WT) (n = 5 and 8) and Pgc-1β-/- (n = 9 and 6), mice were anaesthetised and used for electrocardiographic (ECG) recordings. Time intervals separating successive ECG deflections were analysed for differences between groups before and after β1-adrenergic (intraperitoneal dobutamine 3 mg/kg) challenge. Heart rates before dobutamine challenge were indistinguishable between groups. The Pgc-1β-/- genotype however displayed compromised nodal function in response to adrenergic challenge. This manifested as an impaired heart rate response suggesting a functional defect at the level of the sino-atrial node, and a negative dromotropic response suggesting an atrioventricular conduction defect. Incidences of the latter were most pronounced in the aged Pgc-1β-/- mice. Moreover, Pgc-1β-/- mice displayed electrocardiographic features consistent with the existence of a pro-arrhythmic substrate. Firstly, ventricular activation was prolonged in these mice consistent with slowed action potential conduction and is reported here for the first time. Additionally, Pgc-1β-/- mice had shorter repolarisation intervals. These were likely attributable to altered K+ conductance properties, ultimately resulting in a shortened QTc interval, which is also known to be associated with increased arrhythmic risk. ECG analysis thus yielded electrophysiological findings bearing on potential arrhythmogenicity in intact Pgc-1β-/- systems in widespread cardiac regions.
  16. Ahmad H, Ahmad S, Shah SAA, Khan HU, Khan FA, Ali M, et al.
    J Asian Nat Prod Res, 2018 Feb;20(2):172-181.
    PMID: 28463565 DOI: 10.1080/10286020.2017.1319820
    New lycoctonine-type dual cholinesterase inhibitor, swatinine-C (1), along with three known norditerpenoid alkaloids, hohenackerine (2), aconorine (5) and lappaconitine (6) and two synthetically known but phytochemically new benzene derivatives, methyl 2-acetamidobenzoate (3) and methyl 4-[2-(methoxycarbonyl)anilino]-4-oxobutanoate (4), was isolated from the roots of A. laeve. Structures of new and known compounds (1-6) were established on the basis of latest spectroscopic techniques and by close comparison with the data available in literature. In vitro, compounds (1-6) were tested against AChE and BChE inhibitory activities. Compounds 1 and 2 showed competitive inhibition against AChE (IC50 = 3.7 μM, 4.53 μM) and BChE (IC50 = 12.23 μM, 9.94 μM), respectively. Compounds 5 and 6 showed promising noncompetitive type of inhibitory profile against AChE (IC50 = 2.51 and 6.13 μM) only. Compounds 3 and 4 showed weak inhibitory profile against both AChE and BChE.
  17. Mohafez H, Ahmad SA, Hadizadeh M, Moghimi S, Roohi SA, Marhaban MH, et al.
    Skin Res Technol, 2018 Feb;24(1):45-53.
    PMID: 28557064 DOI: 10.1111/srt.12388
    PURPOSE: We aimed to develop a method for quantitative assessment of wound healing in ulcerated diabetic feet.

    METHODS: High-frequency ultrasound (HFU) images of 30 wounds were acquired in a controlled environment on post-debridement days 7, 14, 21, and 28. Meaningful features portraying changes in structure and intensity of echoes during healing were extracted from the images, their relevance and discriminatory power being verified by analysis of variance. Relative analysis of tissue healing was conducted by developing a features-based healing function, optimised using the pattern-search method. Its performance was investigated through leave-one-out cross-validation technique and reconfirmed using principal component analysis.

    RESULTS: The constructed healing function could depict tissue changes during healing with 87.8% accuracy. The first principal component derived from the extracted features demonstrated similar pattern to the constructed healing function, accounting for 86.3% of the data variance.

    CONCLUSION: The developed wound analysis technique could be a viable tool in quantitative assessment of diabetic foot ulcers during healing.

  18. Jusoh Z, Tohid H, Omar K, Muhammad NA, Ahmad S
    Malays J Med Sci, 2018 Feb;25(1):84-95.
    PMID: 29599638 MyJurnal DOI: 10.21315/mjms2018.25.1.10
    Background: The quality of life (QoL) describes the multidimensional self-perceived well-being of a person, which is an important diabetes outcome. This study aimed to measure the QoL scores among patients with type 2 diabetes mellitus (T2DM), as well as their clinical and sociodemographic predictors.

    Methods: This cross-sectional study involved 180 randomly sampled patients at a primary care clinic on the East Coast of Peninsular Malaysia. A self-administered questionnaire containing the Audit of Diabetes Dependent Quality of Life-18 (ADDQoL-18) was used.

    Results: Most of the respondents (96.7%) were Malay, with a median (interquartile range, IQR) age of 54.0 (14.0) years old. The majority of them were females (60.0%), married (81.1%) and from low-income families (63.3%), who attained a secondary education or lower (75.6%). Only 49.4% of them were employed. The mean (standard deviation, SD) ADDQoL-18 average weighted impact score was -4.58 (2.21) and all 18 domains were negatively affected, particularly the living condition, family life and working life. The multiple linear regression analysis showed that the age (adjusted B = 0.05,P= 0.004) and insulin use (adjusted B = -0.84,P= 0.011) were QoL predictors.

    Conclusion: T2DM negatively impacts the patient's QoL in all aspects of their life. The QoL improvement with age suggests that the older patients had accepted and adapted to their illness. The need to improve the QoL among insulin users was also highlighted.
    Study site: Klinik Kesihatan, Malaysia
  19. Valli H, Ahmad S, Jiang AY, Smyth R, Jeevaratnam K, Matthews HR, et al.
    Mech Ageing Dev, 2018 01;169:1-9.
    PMID: 29197478 DOI: 10.1016/j.mad.2017.11.016
    INTRODUCTION: Recent studies reported that energetically deficient murine Pgc-1β-/- hearts replicate age-dependent atrial arrhythmic phenotypes associated with their corresponding clinical conditions, implicating action potential (AP) conduction slowing consequent upon reduced AP upstroke rates.

    MATERIALS AND METHODS: We tested a hypothesis implicating Na+ current alterations as a mechanism underlying these electrophysiological phenotypes. We applied loose patch-clamp techniques to intact young and aged, WT and Pgc-1β-/-, atrial cardiomyocyte preparations preserving their in vivo extracellular and intracellular conditions.

    RESULTS AND DISCUSSION: Depolarising steps activated typical voltage-dependent activating and inactivating inward (Na+) currents whose amplitude increased or decreased with the amplitudes of the activating, or preceding inactivating, steps. Maximum values of peak Na+ current were independently influenced by genotype but not age or interacting effects of genotype and age on two-way ANOVA. Neither genotype, nor age, whether independently or interactively, influenced voltages at half-maximal current, or steepness factors, for current activation and inactivation, or time constants for recovery from inactivation following repolarisation. In contrast, delayed outward (K+) currents showed similar activation and rectification properties through all experimental groups. These findings directly demonstrate and implicate reduced Na+ in contrast to unchanged K+ current, as a mechanism for slowed conduction causing atrial arrhythmogenicity in Pgc-1β-/- hearts.

  20. Rajendran Royan NR, Sulong AB, Yuhana NY, Chen RS, Ab Ghani MH, Ahmad S
    PLoS One, 2018;13(5):e0197345.
    PMID: 29847568 DOI: 10.1371/journal.pone.0197345
    The use of rice husks (RH) to reinforce polymers in biocomposites are increasing tremendously. However, the incompatibility between the hydrophilic RH fibers and the hydrophobic thermoplastic matrices leads to unsatisfactory biocomposites. Surface modification of the fiber surface was carried out to improve the adhesion between fiber and matrix. In this study, the effect of surface modification of RH via alkali, acid and ultraviolet-ozonolysis (UV/O3) treatments on the properties of composites recycled high density polyethylene (rHDPE) composites was investigated. The untreated and treated RH were characterized by Fourier Transform Infrared (FTIR) and Scanning Electron Microscope (SEM). The composites containing 30 wt% of RH (treated and untreated) were then prepared via extrusion and followed by compression molding. As compared to untreated RH, all surface treated RH exhibited rougher surface and showed improved adhesion with rHDPE matrix. Tensile strength of UV/O3-treated RH composites showed an optimum result at 18.37 MPa which improved about 5% in comparison to the composites filled with untreated RH. UV/O3 treatment promotes shorter processing time and lesser raw material waste during treatment process where this is beneficial for commercialization in the future developments of wood plastic composites (WPCs). Therefore, UV/O3 treatment can be served as an alternative new method to modify RH surface in order to improve the adhesion between hydrophilic RH fibre and hydrophobic rHDPE polymer matrix.
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