Displaying publications 81 - 100 of 2380 in total

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  1. Hwong WY, Bots ML, Selvarajah S, Abdul Aziz Z, Sidek NN, Spiering W, et al.
    PLoS One, 2016;11(11):e0166524.
    PMID: 27846309 DOI: 10.1371/journal.pone.0166524
    BACKGROUND: The increase in angiotensin II (Ang II) formation by selected antihypertensive drugs is said to exhibit neuroprotective properties, but this translation into improvement in clinical outcomes has been inconclusive. We undertook a study to investigate the relationship between types of antihypertensive drugs used prior to a stroke event and ischemic stroke severity. We hypothesized that use of antihypertensive drugs that increase Ang II formation (Ang II increasers) would reduce ischemic stroke severity when compared to antihypertensive drugs that suppress Ang II formation (Ang II suppressors).

    METHODS: From the Malaysian National Neurology Registry, we included hypertensive patients with first ischemic stroke who presented within 48 hours from ictus. Antihypertensive drugs were divided into Ang II increasers (angiotensin-I receptor blockers (ARBs), calcium channel blockers (CCBs) and diuretics) and Ang II suppressors (angiotensin-converting-enzyme inhibitors (ACEIs) and beta blockers). We evaluated stroke severity during admission with the National Institute of Health Stroke Scale (NIHSS). We performed a multivariable logistic regression with the score being dichotomized at 15. Scores of less than 15 were categorized as less severe stroke.

    RESULTS: A total of 710 patients were included. ACEIs was the most commonly prescribed antihypertensive drug in patients using Ang II suppressors (74%) and CCBs, in patients prescribed with Ang II increasers at 77%. There was no significant difference in the severity of ischemic stroke between patients who were using Ang II increasers in comparison to patients with Ang II suppressors (OR: 1.32, 95%CI: 0.83-2.10, p = 0.24).

    CONCLUSION: In our study, we found that use of antihypertensive drugs that increase Ang II formation was not associated with less severe ischemic stroke as compared to use of antihypertensive drugs that suppress Ang II formation.

  2. Adeyemi O, Alvarez-Laviada A, Schultz F, Ibrahim E, Trauner M, Williamson C, et al.
    PLoS One, 2017;12(9):e0183167.
    PMID: 28934223 DOI: 10.1371/journal.pone.0183167
    BACKGROUND: Increased maternal serum bile acid concentrations in intrahepatic cholestasis of pregnancy (ICP) are associated with fetal cardiac arrhythmias. Ursodeoxycholic acid (UDCA) has been shown to demonstrate anti-arrhythmic properties via preventing ICP-associated cardiac conduction slowing and development of reentrant arrhythmias, although the cellular mechanism is still being elucidated.

    METHODS: High-resolution fluorescent optical mapping of electrical activity and electrocardiogram measurements were used to characterize effects of UDCA on one-day-old neonatal and adult female Langendorff-perfused rat hearts. ICP was modelled by perfusion of taurocholic acid (TC, 400μM). Whole-cell calcium currents were recorded from neonatal rat and human fetal cardiomyocytes.

    RESULTS: TC significantly prolonged the PR interval by 11.0±3.5% (P<0.05) and slowed ventricular conduction velocity (CV) by 38.9±5.1% (P<0.05) exclusively in neonatal and not in maternal hearts. A similar CV decline was observed with the selective T-type calcium current (ICa,T) blocker mibefradil 1μM (23.0±6.2%, P<0.05), but not with the L-type calcium current (ICa,L) blocker nifedipine 1μM (6.9±6.6%, NS). The sodium channel blocker lidocaine (30μM) reduced CV by 60.4±4.5% (P<0.05). UDCA co-treatment was protective against CV slowing induced by TC and mibefradil, but not against lidocaine. UDCA prevented the TC-induced reduction in the ICa,T density in both isolated human fetal (-10.2±1.5 versus -5.5±0.9 pA/pF, P<0.05) and neonatal rat ventricular myocytes (-22.3±1.1 versus -9.6±0.8 pA/pF, P<0.0001), whereas UDCA had limited efficacy on the ICa,L.

    CONCLUSION: Our findings demonstrate that ICa,T plays a significant role in ICP-associated fetal cardiac conduction slowing and arrhythmogenesis, and is an important component of the fetus-specific anti-arrhythmic activity of UDCA.

  3. Jaffar A, Mohd-Sidik S, Nien FC, Fu GQ, Talib NH
    PLoS One, 2020;15(7):e0236140.
    PMID: 32667936 DOI: 10.1371/journal.pone.0236140
    BACKGROUND: Urinary Incontinence (UI) is when a person is unable to hold his/her urine effectively. This is a common problem which can develop and worsen during pregnancy. An effective way to manage UI is to educate patients on the Pelvic Floor Muscle Exercise (PFME) regularly. The present study aimed to ascertain the pregnant women's knowledge, attitudes, and practices (KAP) related to PFME.

    METHODS: This was a cross-sectional study done in a one primary care clinic located in a semi-urban area in Selangor, Malaysia. Simple random sampling was conducted among pregnant women aged 18 years old and above at any gestation. The validated study instruments used consisted of questions on socio-demography, KAP on UI, and also the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form to determine UI among the respondents.

    RESULTS: The response rate for this study was 72.1%, where 440 pregnant women consented to take part in the study. The median age of study respondents was 30 years old and majority of the study respondents was from the Malay ethnicity (80.9%). The prevalence of UI was 40.9%. The proportion of pregnant women with good knowledge, attitude and practice scores were 58.0%, 46.6% and 45.2% respectively. There was a significant association between UI and age (p = .03), body mass index (p = .03), ethnicity (p = .04), gravida. (p = .001), knowledge on PFME (p = .007) and attitude towards PFME (p = .006).

    CONCLUSIONS: Findings from this study fill a gap in the prevalence and KAP concerning PFME at the primary care level. The foundation areas for future education and health promotion on UI should address the importance of correct PFME. This education can be delivered through a pragmatic way to ensure its effectiveness and sustainability of the health promotion program.

  4. Gondos AS, Al-Moyed KA, Al-Robasi AB, Al-Shamahy HA, Alyousefi NA
    PLoS One, 2015;10(12):e0144266.
    PMID: 26657128 DOI: 10.1371/journal.pone.0144266
    Urinary tract infection (UTI) is the most common complication following kidney transplantation (KT), which could result in losing the graft. This study aims to identify the prevalence of bacterial UTI among KT recipients in Yemen and to determine the predisposing factors associated with post renal transplantation UTI. A cross sectional study included of 150 patients, who underwent KT was conducted between June 2010 and January 2011. A Morning mid-stream urine specimen was collected for culture and antibiotic susceptibility test from each recipient. Bacterial UTI was found in 50 patients (33.3%). The prevalence among females 40.3% was higher than males 29%. The UTI was higher in the age group between 41-50 years with a percentage of 28% and this result was statistically significant. Predisposing factors as diabetes mellitus, vesicoureteral reflux, neurogenic bladder and polycystic kidney showed significant association. High relative risks were found for polycystic kidney = 13.5 and neurogenic bladder = 13.5. The most prevalent bacteria to cause UTI was Escherichia coli represent 44%, followed by Staphylococcus saprophyticus 34%. Amikacin was the most effective antibiotic against gram-negative isolates while Ciprofloxacin was the most effective antibiotic against Staphylococcus saprophyticus. In conclusion, there is high prevalence of bacterial UTI among KT recipients in Yemen. Diabetes mellitus, vesicoureteral reflux, neurogenic bladder, polycystic kidney and calculi were the main predisposing factors.
  5. Singh GK, Balzer BW, Kelly PJ, Paxton K, Hawke CI, Handelsman DJ, et al.
    PLoS One, 2015;10(11):e0143555.
    PMID: 26599397 DOI: 10.1371/journal.pone.0143555
    The longitudinal relationships of within-individual hormone and anthropometric changes during puberty have not ever been fully described. The objectives of this study were to demonstrate that 3 monthly urine collection was feasible in young adolescents and to utilise liquid chromatography-tandem mass spectrometry assay methods for serum and urine testosterone (T), estradiol (E2) and luteinizing hormone (LH) in adolescents by relating temporal changes in urine and serum hormones over 12 months to standard measures of pubertal development.
  6. Phan CW, David P, Wong KH, Naidu M, Sabaratnam V
    PLoS One, 2015;10(11):e0143004.
    PMID: 26565787 DOI: 10.1371/journal.pone.0143004
    Neurodegenerative diseases are linked to neuronal cell death and impairment of neurite outgrowth. An edible mushroom, Pleurotus giganteus was found to stimulate neurite outgrowth in vitro but the chemical constituents and the underlying mechanism is yet to be elucidated. The chemical constituents of P. giganteus (linoleic acid, oleic acid, cinnamic acid, caffeic acid, p-coumaric acid, succinic acid, benzoic acid, and uridine) were tested for neurite outgrowth activity. Uridine (100 μM) was found to increase the percentage of neurite-bearing cells of differentiating neuroblastoma (N2a) cells by 43.1 ± 0.5%, which was 1.8-fold higher than NGF (50 ng/mL)-treated cells. Uridine which was present in P. giganteus (1.80 ± 0.03 g/100g mushroom extract) increased the phosphorylation of extracellular-signal regulated kinases (ERKs) and protein kinase B (Akt). Further, phosphorylation of the mammalian target of rapamycin (mTOR) was also increased. MEK/ERK and PI3K-Akt-mTOR further induced phosphorylation of cAMP-response element binding protein (CREB) and expression of growth associated protein 43 (GAP43); all of which promoted neurite outgrowth of N2a cells. This study demonstrated that P. giganteus may enhance neurite outgrowth and one of the key bioactive molecules responsible for neurite outgrowth is uridine.
  7. Menon PS, Said FA, Mei GS, Berhanuddin DD, Umar AA, Shaari S, et al.
    PLoS One, 2018;13(7):e0201228.
    PMID: 30052647 DOI: 10.1371/journal.pone.0201228
    This work investigates the surface plasmon resonance (SPR) response of 50-nm thick nano-laminated gold film using Kretschmann-based biosensing for detection of urea and creatinine in solution of various concentrations (non-enzymatic samples). Comparison was made with the presence of urease and creatininase enzymes in the urea and creatinine solutions (enzymatic samples), respectively. Angular interrogation technique was applied using optical wavelengths of 670 nm and 785 nm. The biosensor detects the presence of urea and creatinine at concentrations ranging from 50-800 mM for urea samples and 10-200 mM for creatinine samples. The purpose of studying the enzymatic sample was mainly to enhance the sensitivity of the sensor towards urea and creatinine in the samples. Upon exposure to 670 nm optical wavelength, the sensitivity of 1.4°/M was detected in non-enzymatic urea samples and 4°/M in non-enzymatic creatinine samples. On the other hand, sensor sensitivity as high as 16.2°/M in urea-urease samples and 10°/M in creatinine-creatininase samples was detected. The enhanced sensitivity possibly attributed to the increase in refractive index of analyte sensing layer due to urea-urease and creatinine-creatininase coupling activity. This work has successfully proved the design and demonstrated a proof-of-concept experiment using a low-cost and easy fabrication of Kretschmann based nano-laminated gold film SPR biosensor for detection of urea and creatinine using urease and creatininase enzymes.
  8. Abd Khalim MA, Sukeri S
    PLoS One, 2023;18(1):e0278404.
    PMID: 36649258 DOI: 10.1371/journal.pone.0278404
    Malaysia's subsidised public healthcare system is heavily reliant on government funding. Increasing the uptake of private health insurance (PHI) would alleviate the financial burden on public healthcare facilities caused by high patient loads. The study aimed to determine the uptake of PHI and its associated factors among the East Coast Malaysian populations. A cross-sectional online survey was conducted between February and June 2021. Proportionate stratified sampling was applied to select 1138 participants, and logistic regression was performed to determine the factors associated with PHI uptake. The proportion of the study samples that purchased PHI was 54.3%. Enrolment of private health insurance was associated with working in the public sector (aOR: 6.06, 95% CI: 2.65, 13.88) and private sector (aOR: 6.27, 95% CI: 2.65, 14.85), being self-employed (aOR: 9.23, 95% CI: (3.59, 23.70), being in the middle 40% household income percentile (aOR: 2.74, 95% CI: 1.95, 3.85) and top 20% household income percentile (aOR: 4.42, 95% CI: 2.87, 6.80), and living in urban areas (aOR: 1.31, 95% CI: 1.01, 1.70). Even in the presence of subsidised public healthcare, the high proportion of PHI uptake reflects a demand for private health insurance. The study suggests that PHI should be promoted among those who are employed or self-employed, the middle- and high-income groups, and urban residents. The findings may be beneficial for the government and insurance companies to improve strategies to enhance PHI uptake among these population.
  9. Ahmad A, Sattar MA, Rathore HA, Abdulla MH, Khan SA, Azam M, et al.
    PLoS One, 2016;11(3):e0150137.
    PMID: 26963622 DOI: 10.1371/journal.pone.0150137
    Hydrogen sulphide (H2S) is an emerging molecule in many cardiovascular complications but its role in left ventricular hypertrophy (LVH) is unknown. The present study explored the effect of exogenous H2S administration in the regression of LVH by modulating oxidative stress, arterial stiffness and expression of cystathione γ lyase (CSE) in the myocardium. Animals were divided into four groups: Control, LVH, Control-H2S and LVH-H2S. LVH was induced by administering isoprenaline (5mg/kg, every 72 hours, S/C) and caffeine in drinking water (62mg/L) for 2 weeks. Intraperitoneal NaHS, 56μM/kg/day for 5 weeks, was given as an H2S donor. Myocardial expression of Cystathione γ lyase (CSE) mRNA was quantified using real time polymerase chain reaction (qPCR).There was a 3 fold reduction in the expression of myocardial CSE mRNA in LVH but it was up regulated by 7 and 4 fold in the Control-H2S and LVH-H2S myocardium, respectively. Systolic blood pressure, mean arterial pressure, pulse wave velocity were reduced (all P<0.05) in LVH-H2S when compared to the LVH group. Heart, LV weight, myocardial thickness were reduced while LV internal diameter was increased (all P<0.05) in the LVH-H2S when compared to the LVH group. Exogenous administration of H2S in LVH increased superoxide dismutase, glutathione and total antioxidant capacity but significantly reduced (all P<0.05) plasma malanodialdehyde in the LVH-H2S compared to the LVH group. The renal cortical blood perfusion increased by 40% in LVH-H2S as compared to the LVH group. Exogenous administration of H2S suppressed the progression of LVH which was associated with an up regulation of myocardial CSE mRNA/ H2S and a reduction in pulse wave velocity with a blunting of systemic hemodynamic. This CSE/H2S pathway exhibits an antihypertrophic role by antagonizing the hypertrophic actions of angiotensin II(Ang II) and noradrenaline (NA) but attenuates oxidative stress and improves pulse wave velocity which helps to suppress LVH. Exogenous administration of H2S augmented the reduced renal cortical blood perfusion in the LVH state.
  10. Raza A, Jauhar J, Abdul Rahim NF, Memon U, Matloob S
    PLoS One, 2023;18(10):e0288527.
    PMID: 37796908 DOI: 10.1371/journal.pone.0288527
    In Pakistan, women outnumber men in medical colleges with 80 percent enrollment, yet many fail to practice medicine following graduation. Pakistan Medical Council (PMC) states 50 percent of graduated women doctors either did not practice or left employment in a short period. Thus, the non-servicing women doctors are assumed as the one of the major causes for the overall doctors' shortage in the country. Addressing this enduring matter, this study aims to explore and understand the factors that discourage women doctors from practicing medicine in Pakistani hospitals. The study employed qualitative exploratory inquiry with an interpretive paradigm to attain a deeper understanding of the problem. 59-semi structured interviews were conducted by non-working women doctors across the entirety of Pakistan. The narratives were then analyzed by thematic analysis using ATLAS.ti 22. The findings have resulted in the three major themes, i.e., workplace challenges, socio-cultural obstructions, and familial restrictions that possibly obstruct women from practicing medicine in hospitals. The findings suggested that accepting traditional cultural values, including entrenched gender roles in society, deters women from practicing medicine. The prevailing patriarchal societal system includes stereotypes against working women; early marriages hinder women from practicing medicine. The prevailing societal system upholds the influence of in-laws and a husband for women doctor professional employment. As a result, severe work-life conflict was reported where most women doctors ended up in their profession in the middle of struggling between socially rooted gender roles as homemakers and their professional careers-furthermore, the study found various workplace issues that posit an additional burden on already struggling women doctors. Issues include poor recruitment and selection process, transfer constraints, excessive workload with inadequate salary, harassment, gender discrimination, unsafe work environment, and little support from the administration highly contribute to the shortage of women doctors in Pakistan.
  11. Chang CY, Koh CL, Sam CK, Chan XY, Yin WF, Chan KG
    PLoS One, 2012;7(8):e44034.
    PMID: 22952864 DOI: 10.1371/journal.pone.0044034
    Growth-dependent cell-cell communication termed quorum sensing is a key regulatory system in bacteria for controlling gene expression including virulence factors. In this study five potential bacterial pathogens including Bacillus sp. W2.2, Klebsiella sp. W4.2, Pseudomonas sp. W3 and W3.1 and Serratia sp. W2.3 were isolated from diseased Tilapia fish in Malaysia, supplied by the leading global fish supplier. Proteolytic activity assays confirmed that with the exception of Klebsiella sp. W4.2, all isolates showed distinct proteolytic activity. Furthermore Bacillus sp. W2.2 and Pseudomonas sp. strains W3 and W3.1 also displayed haemolytic activity. By using high resolution liquid chromatography mass spectrometry, we revealed the presence of unusually long-chain N-(3-oxohexadecanoyl)-homoserine lactone (3-oxo-C16-HSL) from Pseudomonas sp. W3.1 and N-dodecanoyl-homoserine lactone (C12-HSL) from Serratia sp. W2.3, respectively. Interestingly, Pseudomonas sp. W3.1 also produced a wide range of Pseudomonas quinolone signalling (PQS) molecules. Pseudomonas sp. W3 did not show any quorum sensing properties but possessed quorum quenching activity that inactivated AHLs. This study is the first documentation that shows unusual long-chain AHLs production in Serratia sp. and Pseudomonas sp. isolated from diseased fish and the latter also produce a wide range of PQS molecules.
  12. May Z, Alam MK, Mahmud MS, Rahman NAA
    PLoS One, 2020;15(11):e0242022.
    PMID: 33186372 DOI: 10.1371/journal.pone.0242022
    Damage assessment is a key element in structural health monitoring of various industrial applications to understand well and predict the response of the material. The big uncertainty in carbon fiber composite materials response is because of variability in the initiation and propagation of damage. Developing advanced tools to design with composite materials, methods for characterizing several damage modes during operation are required. While there is a significant amount of work on the analysis of acoustic emission (AE) from different composite materials and many loading cases, this research focuses on applying an unsupervised clustering method for separating AE data into several groups with distinct evolution. In this paper, we develop an adaptive sampling and unsupervised bivariate data clustering techniques to characterize the several damage initiations of a composite structure in different lay-ups. An adaptive sampling technique pre-processes the AE features and eliminates redundant AE data samples. The reduction of unnecessary AE data depends on the requirements of the proposed bivariate data clustering technique. The bivariate data clustering technique groups the AE data (dependent variable) with respect to the mechanical data (independent variable) to assess the damage of the composite structure. Tensile experiments on carbon fiber reinforced composite laminates (CFRP) in different orientations are carried out to collect mechanical and AE data and demonstrate the damage modes. Based on the mechanical stress-strain data, the results show the dominant damage regions in different lay-ups of specimens and the definition of the different states of damage. In addition, the states of the damage are observed using Scanning Electron Microscope (SEM) analysis. Based on the AE data, the results show that the strong linear correlation between AE and mechanical energy, and the classification of various modes of damage in all lay-ups of specimens forming clusters of AE energy with respect to the mechanical energy. Furthermore, the validation of the cluster-based characterization and improvement of the sensitivity of the damage modes classification are observed by the combined knowledge of AE and mechanical energy and time-frequency spectrum analysis.
  13. Massud A, Khan AH, Syed Sulaiman SA, Ahmad N, Shafqat M, Ming LC
    PLoS One, 2023;18(8):e0287966.
    PMID: 37561810 DOI: 10.1371/journal.pone.0287966
    INTRODUCTION: Tuberculosis (TB), a curable and preventable infectious disease, becomes difficult to treat if resistance against most effective and tolerable first line anti-TB drugs is developed. The objective of the present study was to evaluate the treatment outcomes and predictors of poor outcomes among drug-resistant tuberculosis (DR-TB) patients treated at a programmatic management unit of drug resistant tuberculosis (PMDT) unit, Punjab, Pakistan.

    METHODS: This prospective observational study was conducted at a a PMDT unit in Multan, Punjab, Pakistan. A total of 271 eligible culture positive DR-TB patients enrolled for treatment at the study site between January 2016 and May 2017 were followed till their treatment outcomes were recorded. World Health Organization's (WHO) defined criteria was used for categorizing treatment outcomes. The outcomes of cured and treatment completed were collectively placed as successful outcomes, while death, lost to follow-up (LTFU) and treatment failure were grouped as unsuccessful outcomes. Multivariable binary logistic regression analysis was employed for getting predictors of unsuccessful treatment outcomes. A p-value <0.05 was considered statistically significant.

    RESULTS: Of the 271 DR-TB patients analysed, nearly half (51.3%) were males. The patient's (Mean ± SD) age was 36.75 ± 15.69 years. A total of 69% patients achieved successful outcomes with 185 (68.2%) patients being cured and 2 (0.7%) completed therapy. Of the remaining 84 patients with unsuccessful outcomes, 48 (17.7%) died, 2 (0.7%) were declared treatment failure, 34 (12.5%) were loss to follow up. After adjusting for confounders, patients' age > 50 years (OR 2.149 (1.005-4.592) with p-value 0.048 and baseline lung cavitation (OR 7.798 (3.82-15.919) with p-value <0.001 were significantly associated with unsuccessful treatment outcomes.

    CONCLUSIONS: The treatment success rate (69%) in the current study participants was below the target set by WHO (>75%). Paying special attention and timely intervention in patients with high risk of unsuccessful treatment outcomes may help in improving treatment outcomes at the study site.

  14. Samiulhaq, Ahmad S, Vieru D, Khan I, Shafie S
    PLoS One, 2014;9(5):e88766.
    PMID: 24785147 DOI: 10.1371/journal.pone.0088766
    Magnetic field influence on unsteady free convection flow of a second grade fluid near an infinite vertical flat plate with ramped wall temperature embedded in a porous medium is studied. It has been observed that magnitude of velocity as well as skin friction in case of ramped temperature is quite less than the isothermal temperature. Some special cases namely: (i) second grade fluid in the absence of magnetic field and porous medium and (ii) Newtonian fluid in the presence of magnetic field and porous medium, performing the same motion are obtained. Finally, the influence of various parameters is graphically shown.
  15. Hussanan A, Zuki Salleh M, Tahar RM, Khan I
    PLoS One, 2014;9(10):e108763.
    PMID: 25302782 DOI: 10.1371/journal.pone.0108763
    In this paper, the heat transfer effect on the unsteady boundary layer flow of a Casson fluid past an infinite oscillating vertical plate with Newtonian heating is investigated. The governing equations are transformed to a systems of linear partial differential equations using appropriate non-dimensional variables. The resulting equations are solved analytically by using the Laplace transform method and the expressions for velocity and temperature are obtained. They satisfy all imposed initial and boundary conditions and reduce to some well-known solutions for Newtonian fluids. Numerical results for velocity, temperature, skin friction and Nusselt number are shown in various graphs and discussed for embedded flow parameters. It is found that velocity decreases as Casson parameters increases and thermal boundary layer thickness increases with increasing Newtonian heating parameter.
  16. Gul T, Islam S, Shah RA, Khalid A, Khan I, Shafie S
    PLoS One, 2015;10(7):e0126698.
    PMID: 26147287 DOI: 10.1371/journal.pone.0126698
    This paper studies the unsteady magnetohydrodynamics (MHD) thin film flow of an incompressible Oldroyd-B fluid over an oscillating inclined belt making a certain angle with the horizontal. The problem is modeled in terms of non-linear partial differential equations with some physical initial and boundary conditions. This problem is solved for the exact analytic solutions using two efficient techniques namely the Optimal Homotopy Asymptotic Method (OHAM) and Homotopy Perturbation Method (HPM). Both of these solutions are presented graphically and compared. This comparison is also shown in tabular form. An excellent agreement is observed. The effects of various physical parameters on velocity have also been studied graphically.
  17. Ullah I, Bhattacharyya K, Shafie S, Khan I
    PLoS One, 2016;11(10):e0165348.
    PMID: 27776174 DOI: 10.1371/journal.pone.0165348
    Numerical results are presented for the effect of first order chemical reaction and thermal radiation on mixed convection flow of Casson fluid in the presence of magnetic field. The flow is generated due to unsteady nonlinearly stretching sheet placed inside a porous medium. Convective conditions on wall temperature and wall concentration are also employed in the investigation. The governing partial differential equations are converted to ordinary differential equations using suitable transformations and then solved numerically via Keller-box method. It is noticed that fluid velocity rises with increase in radiation parameter in the case of assisting flow and is opposite in the case of opposing fluid while radiation parameter has no effect on fluid velocity in the forced convection. It is also seen that fluid velocity and concentration enhances in the case of generative chemical reaction whereas both profiles reduces in the case of destructive chemical reaction. Further, increase in local unsteadiness parameter reduces fluid velocity, temperature and concentration. Over all the effects of physical parameters on fluid velocity, temperature and concentration distribution as well as on the wall shear stress, heat and mass transfer rates are discussed in detail.
  18. Azzeri A, Mohamed NA, Wan Rosli SH, Abdul Samat MN, Rashid ZZ, Mohamad Jamali MA, et al.
    PLoS One, 2024;19(3):e0291892.
    PMID: 38483913 DOI: 10.1371/journal.pone.0291892
    Genomic surveillance is crucial for tracking emergence and spread of novel variants of pathogens, such as SARS-CoV-2, to inform public health interventions and to enforce control measures. However, in some settings especially in low- and middle- income counties, where sequencing platforms are limited, only certain patients get to be selected for sequencing surveillance. Here, we show that patients with multiple comorbidities potentially harbour SARS-CoV-2 with higher mutation rates and thus deserve more attention for genomic surveillance. The relationship between the patient comorbidities, and type of amino acid mutations was assessed. Correlation analysis showed that there was a significant tendency for mutations to occur within the ORF1a region for patients with higher number of comorbidities. Frequency analysis of the amino acid substitution within ORF1a showed that nsp3 P822L of the PLpro protease was one of the highest occurring mutations. Using molecular dynamics, we simulated that the P822L mutation in PLpro represents a system with lower Root Mean Square Deviation (RMSD) fluctuations, and consistent Radius of gyration (Rg), Solvent Accessible Surface Area (SASA) values-indicate a much stabler protein than the wildtype. The outcome of this study will help determine the relationship between the clinical status of a patient and the mutations of the infecting SARS-CoV-2 virus.
  19. Kayani UN, Aysan AF, Gul A, Haider SA, Ahmad S
    PLoS One, 2023;18(10):e0291261.
    PMID: 37819995 DOI: 10.1371/journal.pone.0291261
    Maintaining a stable exchange rate is a challenging task for the world, especially for developing economies. This study examines the impact of asymmetric exchange rates on trade flows in selected Asian countries and finds that the effects of increased exchange rate volatility on exports and imports differ among Pakistan, Malaysia, Japan, and Korea. The quarterly data from the period 1980 to 2018 is collected from the International Financial Statistics (IFS) database maintained by the International Monetary Fund (IMF). We employ both linear and non-linear Autoregressive Distributed Lag (ARDL) models for estimation. The non-linear models yielded more significant findings, while the linear models did not indicate any significant effects of exchange rate volatility on trade flows. The results of the study suggest that in the case of Pakistan, both the linear and non-linear models indicate that increased exchange rate volatility adversely affects exports and imports, while decreased volatility enhances both. This implies that stabilizing the exchange rate would be beneficial for Pakistan's trade. In contrast, the linear model applied to Malaysia shows no long-run effects of exchange rate volatility on exports. However, the result suggests that decreased volatility stimulates Malaysia's exports. Therefore, in the case of Malaysia, stabilizing the exchange rate could contribute to boosting exports. We also found that increased exchange rate volatility boosts exports of Japan. On the other hand, decreased volatility hurts exports of Japan. As for the long-run effects of exchange rate volatility on imports, we found that increased volatility boosts imports of Korea. The study provides various policy implications regarding the impact of exchange rate volatility on trade flows in developing economies. The study highlights the importance of country-specific considerations in understanding the impact of exchange rate volatility on trade flows, and has important policy implications for promoting trade and economic growth in these nations. It emphasizes the need to model exchange rate volatility separately for developed and developing countries and to continue research and analysis to identify ways to mitigate its negative effects on the economy.
  20. Lee CS, Taib NA, Ashrafzadeh A, Fadzli F, Harun F, Rahmat K, et al.
    PLoS One, 2016;11(2):e0149551.
    PMID: 26890881 DOI: 10.1371/journal.pone.0149551
    Heavily glycosylated mucin glycopeptides such as CA 27.29 and CA 15-3 are currently being used as biomarkers for detection and monitoring of breast cancer. However, they are not well detected at the early stages of the cancer. In the present study, perchloric acid (PCA) was used to enhance detection of mucin-type O-glycosylated proteins in the serum in an attempt to identify new biomarkers for early stage breast cancer. Sensitivity and specificity of an earlier developed sandwich enzyme-linked lectin assay were significantly improved with the use of serum PCA isolates. When a pilot case-control study was performed using the serum PCA isolates of normal participants (n = 105) and patients with stage 0 (n = 31) and stage I (n = 48) breast cancer, higher levels of total O-glycosylated proteins in sera of both groups of early stage breast cancer patients compared to the normal control women were demonstrated. Further analysis by gel-based proteomics detected significant inverse altered abundance of proteoglycan 4 and plasma protease C1 inhibitor in both the early stages of breast cancer patients compared to the controls. Our data suggests that the ratio of serum proteoglycan 4 to protease C1 inhibitor may be used for screening of early breast cancer although this requires further validation in clinically representative populations.
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