Displaying publications 1 - 20 of 107 in total

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  1. Yusof W, Irekeola AA, Wada Y, Engku Abd Rahman ENS, Ahmed N, Musa N, et al.
    Life (Basel), 2021 Nov 11;11(11).
    PMID: 34833100 DOI: 10.3390/life11111224
    Since its first detection in December 2019, more than 232 million cases of COVID-19, including 4.7 million deaths, have been reported by the WHO. The SARS-CoV-2 viral genomes have evolved rapidly worldwide, causing the emergence of new variants. This systematic review and meta-analysis was conducted to provide a global mutational profile of SARS-CoV-2 from December 2019 to October 2020. The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA), and a study protocol was lodged with PROSPERO. Data from 62 eligible studies involving 368,316 SARS-CoV-2 genomes were analyzed. The mutational data analyzed showed most studies detected mutations in the Spike protein (n = 50), Nucleocapsid phosphoprotein (n = 34), ORF1ab gene (n = 29), 5'-UTR (n = 28) and ORF3a (n = 25). Under the random-effects model, pooled prevalence of SARS-CoV-2 variants was estimated at 95.1% (95% CI; 93.3-96.4%; I2 = 98.952%; p = 0.000) while subgroup meta-analysis by country showed majority of the studies were conducted 'Worldwide' (n = 10), followed by 'Multiple countries' (n = 6) and the USA (n = 5). The estimated prevalence indicated a need to continuously monitor the prevalence of new mutations due to their potential influence on disease severity, transmissibility and vaccine effectiveness.
  2. Yaw CT, Koh SP, Sandhya M, Ramasamy D, Kadirgama K, Benedict F, et al.
    Nanomaterials (Basel), 2023 May 10;13(10).
    PMID: 37242013 DOI: 10.3390/nano13101596
    Response surface methodology (RSM) is used in this study to optimize the thermal characteristics of single graphene nanoplatelets and hybrid nanofluids utilizing the miscellaneous design model. The nanofluids comprise graphene nanoplatelets and graphene nanoplatelets/cellulose nanocrystal nanoparticles in the base fluid of ethylene glycol and water (60:40). Using response surface methodology (RSM) based on central composite design (CCD) and mini tab 20 standard statistical software, the impact of temperature, volume concentration, and type of nanofluid is used to construct an empirical mathematical formula. Analysis of variance (ANOVA) is applied to determine that the developed empirical mathematical analysis is relevant. For the purpose of developing the equations, 32 experiments are conducted for second-order polynomial to the specified outputs such as thermal conductivity and viscosity. Predicted estimates and the experimental data are found to be in reasonable arrangement. In additional words, the models could expect more than 85% of thermal conductivity and viscosity fluctuations of the nanofluid, indicating that the model is accurate. Optimal thermal conductivity and viscosity values are 0.4962 W/m-K and 2.6191 cP, respectively, from the results of the optimization plot. The critical parameters are 50 °C, 0.0254%, and the category factorial is GNP/CNC, and the relevant parameters are volume concentration, temperature, and kind of nanofluid. From the results plot, the composite is 0.8371. The validation results of the model during testing indicate the capability of predicting the optimal experimental conditions.
  3. Yap WH, Ooi BK, Ahmed N, Lim YM
    J Biosci, 2018 Jun;43(2):277-285.
    PMID: 29872016
    Secretory phospholipase A2-IIA (sPLA2-IIA) is one of the key enzymes causing lipoprotein modification and vascular inflammation. Maslinic acid is a pentacyclic triterpene which has potential cardioprotective and anti-inflammatory properties. Recent research showed that maslinic acid interacts with sPLA2-IIA and inhibits sPLA2-IIA-mediated monocyte differentiation and migration. This study elucidates the potential of maslinic acid in modulating sPLA2-IIA-mediated inflammatory effects in THP-1 macrophages. We showed that maslinic acid inhibits sPLA2-IIA-mediated LDL modification and suppressed foam cell formation. Further analysis revealed that sPLA2-IIA only induced modest LDL oxidation and that inhibitory effect of maslinic acid on sPLA2-IIA-mediated foam cells formation occurred independently of its anti-oxidative properties. Interestingly, maslinic acid was also found to significantly reduce lipid accumulation observed in macrophages treated with sPLA2-IIA only. Flow cytometry analysis demonstrated that the effect observed in maslinic acid might be contributed in part by suppressing sPLA2-IIA-induced endocytic activity, thereby inhibiting LDL uptake. The study further showed that maslinic acid suppresses sPLA2-IIA-induced up-regulation of PGE2 levels while having no effects on COX-2 activity. Other pro-inflammatory mediators TNF-a and IL-6 were not induced in sPLA2-IIA-treated THP-1 macrophages. The findings of this study showed that maslinic acid inhibit inflammatory effects induced by sPLA2-IIA, including foam cells formation and PGE2 production.
  4. Yap WH, Ahmed N, Lim YM
    Lipids, 2016 10;51(10):1153-1159.
    PMID: 27540737 DOI: 10.1007/s11745-016-4186-1
    Maslinic acid is a natural pentacyclic triterpenoid which has anti-inflammatory properties. A recent study showed that secretory phospholipase A2 (sPLA2) may be a potential binding target of maslinic acid. The human group IIA (hGIIA)-sPLA2 is found in human sera and their levels are correlated with severity of inflammation. This study aims to determine whether maslinic acid interacts with hGIIA-sPLA2 and inhibits inflammatory response induced by this enzyme. It is shown that maslinic acid enhanced intrinsic fluorescence of hGIIA-sPLA2 and inhibited its enzyme activity in a concentration-dependent manner. Molecular docking revealed that maslinic acid binds to calcium binding and interfacial phospholipid binding site, suggesting that it inhibit access of catalytic calcium ion for enzymatic reaction and block binding of the enzyme to membrane phospholipid. The hGIIA-sPLA2 enzyme is also responsible in mediating monocyte recruitment and differentiation. Results showed that maslinic acid inhibit hGIIA-sPLA2-induced THP-1 cell differentiation and migration, and the effect observed is specific to hGIIA-sPLA2 as cells treated with maslinic acid alone did not significantly affect the number of adherent and migrated cells. Considering that hGIIA-sPLA2 enzyme is known to hydrolyze glyceroacylphospholipids present in lipoproteins and cell membranes, maslinic acid may bind and inhibit hGIIA-sPLA2 enzymatic activity, thereby reduces the release of fatty acids and lysophospholipids which stimulates monocyte migration and differentiation. This study is the first to report on the molecular interaction between maslinic acid and inflammatory target hGIIA-sPLA2 as well as its effect towards hGIIA-sPLA2-induced THP-1 monocyte adhesive and migratory capabilities, an important immune-inflammation process in atherosclerosis.
  5. Yap WH, Phang SW, Ahmed N, Lim YM
    Mol Cell Biochem, 2018 Oct;447(1-2):93-101.
    PMID: 29374817 DOI: 10.1007/s11010-018-3295-y
    Secretory phospholipase A2 (sPLA2) group of enzymes have been shown to hydrolyze phospholipids, among which sPLA2 Group V (GV) and Group X (GX) exhibit high selectivity towards phosphatidylcholine-rich cellular plasma membranes. The enzymes have recently emerged as key regulators in lipid droplets formation and it is hypothesized that sPLA2-GV and GX enhanced cell proliferation and lipid droplet accumulation in colon cancer cells (HT29). In this study, cell viability and lipid droplet accumulation were assessed by Resazurin assay and Oil-Red-O staining. Interestingly, both sPLA2-GV and GX enzymes reduced intracellular lipid droplet accumulation and did not significantly affect cell proliferation in HT29 cells. Incubation with varespladib, a pan-inhibitor of sPLA2-Group IIA/V/X, further suppressed lipid droplets accumulation in sPLA2-GV but have no effects in sPLA2-GX-treated cells. Further studies using catalytically inactive sPLA2 enzymes showed that the enzymes intrinsic catalytic activity is required for the net reduction of lipid accumulation. Meanwhile, inhibition of intracellular phospholipases (iPLA2-γ and cPLA2-α) unexpectedly enhanced lipid droplet accumulation in both sPLA2-GV and GX-treated cells. The findings suggested an interconnected relationship between extracellular and intracellular phospholipases in lipid cycling. Previous studies indicated that sPLA2 enzymes are linked to cancer development due to their ability to induce release of arachidonic acid and eicosanoids as well as the stimulation of lipid droplet formation. This study showed that the two enzymes work in a distinct manner and they neither confer proliferative advantage nor enhanced the net lipid droplet accumulation in HT29 cells.
  6. Yap KP, Gan HM, Teh CS, Baddam R, Chai LC, Kumar N, et al.
    J Bacteriol, 2012 Nov;194(21):5970-1.
    PMID: 23045488 DOI: 10.1128/JB.01416-12
    Salmonella enterica serovar Typhi is a human pathogen that causes typhoid fever predominantly in developing countries. In this article, we describe the whole genome sequence of the S. Typhi strain CR0044 isolated from a typhoid fever carrier in Kelantan, Malaysia. These data will further enhance the understanding of its host persistence and adaptive mechanism.
  7. Yap KP, Teh CS, Baddam R, Chai LC, Kumar N, Avasthi TS, et al.
    J Bacteriol, 2012 Sep;194(18):5124-5.
    PMID: 22933756 DOI: 10.1128/JB.01062-12
    Salmonella enterica serovar Typhi is the causative agent of typhoid fever, which causes nearly 21.7 million illnesses and 217,000 deaths globally. Herein, we describe the whole-genome sequence of the Salmonella Typhi strain ST0208, isolated from a sporadic case of typhoid fever in Kuala Lumpur, Malaysia. The whole-genome sequence and comparative genomics allow an in-depth understanding of the genetic diversity, and its link to pathogenicity and evolutionary dynamics, of this highly clonal pathogen that is endemic to Malaysia.
  8. Usmani S, Al-Turkait D, Al-Kandari F, Ahmed N
    Clin Nucl Med, 2022 Jan 01;47(1):e43-e44.
    PMID: 34034312 DOI: 10.1097/RLU.0000000000003707
    18F-FDG PET/CT has been found useful for the detection of the source of infection/inflammation in the body. Platelet-rich plasma is a new treatment modality in which plasma is injected subdermally or intradermally for potential hair regrowth into the scalp. We report a case of 43-year-old woman with right breast cancer who underwent surgery, chemotherapy, and radiotherapy 2 years ago and is currently on hormonal therapy. 18F-FDG PET/CT demonstrate incidental findings of increased FDG avidity in the scalp after platelet-rich plasma therapy.
  9. Umar H, Wahab HA, Ahmed N, Fujimura NA, Amjad MW, Bukhari SNA, et al.
    Drug Dev Ind Pharm, 2024 Mar 20.
    PMID: 38451066 DOI: 10.1080/03639045.2024.2326043
    OBJECTIVES: This study aimed to develop, optimize and evaluate glyceryl monooleate (GMO) based cubosomes as a drug delivery system containing cisplatin for treatment of human lung carcinoma.

    SIGNIFICANCE: The significance of this research was to successfully incorporate slightly water soluble and potent anticancer drug (cisplatin) into cubosomes, which provide slow and sustained release of drug for longer period of time.

    METHODS: The delivery system was developed through top-down approach by melting GMO and poloxamer 407 (P407) at 70 °C and then drop-wise addition of warm deionized water (70 °C) containing cisplatin. The formulation then exposed to probe sonicator for about 2 min. A randomized regular two level full factorial design with help of Design Expert was used for optimization of blank cubosomal formulations. Cisplatin loaded cubosomes were then subjected to physico-chemical characterization.

    RESULTS: The characterization of the formulation revealed that it had a sufficient surface charge of -9.56 ± 1.33 mV, 168.25 ± 5.73 nm particle size, and 60.64 ± 0.11% encapsulation efficiency. The in vitro release of cisplatin from the cubosomes at pH 7.4 was observed to be sustained, with 94.5% of the drug being released in 30 h. In contrast, 99% of cisplatin was released from the drug solution in just 1.5 h. In vitro cytotoxicity assay was conducted on the human lung carcinoma NCI-H226 cell line, the cytotoxicity of cisplatin-loaded cubosomes was relative to that of pure cisplatin solution, while blank (without cisplatin) cubosomes were nontoxic.

    CONCLUSIONS: The obtained results demonstrated the successful development of cubosomes for sustained delivery of cisplatin.

  10. Ullah F, Javed F, Mushtaq I, Rahman LU, Ahmed N, Din IU, et al.
    Int J Biol Macromol, 2023 Jan 05;230:123131.
    PMID: 36610570 DOI: 10.1016/j.ijbiomac.2022.123131
    3-D Bioprinting is employed as a novel approach in biofabrication to promote skin regeneration following chronic-wounds and injury. A novel bioink composed of carbohydrazide crosslinked {polyethylene oxide-co- Chitosan-co- poly(methylmethacrylic-acid)} (PEO-CS-PMMA) laden with Nicotinamide and human dermal fibroblast was successfully synthesized via Free radical-copolymerization at 73 °C. The developed bioink was characterized in term of swelling, structural-confirmation by solid state 13C-Nuclear Magnetic Resonance (NMR), morphology, thermal, 3-D Bioprinting via extrusion, rheological and interaction with DNA respectively. The predominant rate of gelation was attributed to the electrostatic interactions between cationic CS and anionic PMMA pendant groups. The morphology of developed bioink presented a porous architecture satisfying the cell and growth-factor viability across the barrier. The thermal analysis revealed two-step degradation with 85 % weight loss in term of decomposition and molecular changes in the bioink moieties By applying low pressure in the range of 25-50 kPa, the optimum reproducibility and printability were determined at 37 °C in the viscosity range of 500-550 Pa. s. A higher survival rate of 92 % was observed for (PEO-CS-PMMA) in comparison to 67 % for pure chitosan built bioink. A binding constant of K ≈ 1.8 × 106 M-1 recognized a thermodynamically stable interaction of (PEO-CS-PMMA) with the Salmon-DNA. Further, the addition of PEO (5.0 %) was addressed with better self-healing and printability to produce skin-tissue constructs to replace the infected skin in human.
  11. Tiruvayipati S, Bhassu S, Kumar N, Baddam R, Shaik S, Gurindapalli AK, et al.
    Gut Pathog, 2013 Dec 11;5(1):37.
    PMID: 24330647 DOI: 10.1186/1757-4749-5-37
    Vibrio parahaemolyticus, an important human pathogen, is associated with gastroenteritis and transmitted through partially cooked seafood. It has become a major concern in the production and trade of marine food products. The prevalence of potentially virulent and pathogenic V. parahaemolyticus in raw seafood is of public health significance. Here we describe the genome sequence of a V. parahaemolyticus isolate of crustacean origin which was cultured from prawns in 2008 in Selangor, Malaysia (isolate PCV08-7). The next generation sequencing and analysis revealed that the genome of isolate PCV08-7 has closest similarity to that of V. parahaemolyticus RIMD2210633. However, there are certain unique features of the PCV08-7 genome such as the absence of TDH-related hemolysin (TRH), and the presence of HU-alpha insertion. The genome of isolate PCV08-7 encodes a thermostable direct hemolysin (TDH), an important virulence factor that classifies PCV08-7 isolate to be a serovariant of O3:K6 strain. Apart from these, we observed that there is certain pattern of genetic rearrangements that makes V. parahaemolyticus PCV08-7 a non-pandemic clone. We present detailed genome statistics and important genetic features of this bacterium and discuss how its survival, adaptation and virulence in marine and terrestrial hosts can be understood through the genomic blueprint and that the availability of genome sequence entailing this important Malaysian isolate would likely enhance our understanding of the epidemiology, evolution and transmission of foodborne Vibrios in Malaysia and elsewhere.
  12. Taha M, Rahim F, Khan AA, Anouar EH, Ahmed N, Shah SAA, et al.
    Sci Rep, 2020 05 14;10(1):7969.
    PMID: 32409737 DOI: 10.1038/s41598-020-64729-3
    The current study describes synthesis of diindolylmethane (DIM) derivatives based-thiadiazole as a new class of urease inhibitors. Diindolylmethane is natural product alkaloid reported to use in medicinal chemistry extensively. Diindolylmethane-based-thiadiazole analogs (1-18) were synthesized and characterized by various spectroscopic techniques 1HNMR, 13C-NMR, EI-MS and evaluated for urease (jack bean urease) inhibitory potential. All compounds showed excellent to moderate inhibitory potential having IC50 value within the range of 0.50 ± 0.01 to 33.20 ± 1.20 µM compared with the standard thiourea (21.60 ± 0.70 µM). Compound 8 (IC50 = 0.50 ± 0.01 µM) was the most potent inhibitor amongst all derivatives. Structure-activity relationships have been established for all compounds. The key binding interactions of most active compounds with enzyme were confirmed through molecular docking studies.
  13. Subramaniam M, In LL, Kumar A, Ahmed N, Nagoor NH
    Sci Rep, 2016;6:19833.
    PMID: 26817684 DOI: 10.1038/srep19833
    Mycobacterium indicus pranii (MIP) is a non-pathogenic mycobacterium, which has been tested on several cancer types like lung and bladder where tumour regression and complete recovery was observed. In discovering the potential cytotoxic elements, a preliminary test was carried out using four different fractions consisting of live bacteria, culture supernatant, heat killed bacteria and heat killed culture supernatant of MIP against two human cancer cells A549 and CaSki by 3-(4,5-dimethyl thiazol)-2,5-diphenyl tetrazolium bromide (MTT) assay. Apoptosis was investigated in MCF-7 and ORL-115 cancer cells by poly-(ADP-ribose) polymerase (PARP) and DNA fragmentation assays. Among four MIP fractions, only heat killed MIP fraction (HKB) showed significant cytotoxicity in various cancer cells with inhibitory concentration, IC50 in the range 5.6-35.0 μl/(1.0 × 10(6) MIP cells/ml), while cytotoxicity effects were not observed in the remaining fractions. HKB did not show cytotoxic effects on non-cancerous cells contrary to cancerous cells, suggesting its safe usage and ability to differentially recognize between these cells. Evaluation on PARP assay further suggested that cytotoxicity in cancer cells were potentially induced via caspase-mediated apoptosis. The cytotoxic and apoptotic effects of MIP HKB have indicated that this fraction can be a good candidate to further identify effective anti-cancer agents.
  14. Subramaniam M, Liew SK, In L, Awang K, Ahmed N, Nagoor NH
    Drug Des Devel Ther, 2018;12:1053-1063.
    PMID: 29750018 DOI: 10.2147/DDDT.S141925
    Background: Drug combination therapy to treat cancer is a strategic approach to increase successful treatment rate. Optimizing combination regimens is vital to increase therapeutic efficacy with minimal side effects.

    Materials and methods: In the present study, we evaluated the in vitro cytotoxicity of double and triple combinations consisting of 1'S-1'-acetoxychavicol acetate (ACA), Mycobacterium indicus pranii (MIP) and cisplatin (CDDP) against 14 various human cancer cell lines to address the need for more effective therapy. Our data show synergistic effects in MCF-7 cells treated with MIP:ACA, MIP:CDDP and MIP:ACA:CDDP combinations. The type of interaction between MIP, ACA and CDDP was evaluated based on combination index being <0.8 for synergistic effect. Identifying the mechanism of cell death based on previous studies involved intrinsic apoptosis and nuclear factor kappa B (NF-κB) and tested in Western blot analysis. Inactivation of NF-κB was confirmed by p65 and IκBα, while intrinsic apoptosis pathway activation was confirmed by caspase-9 and Apaf-1 expression.

    Results: All combinations confirmed intrinsic apoptosis activation and NF-κB inactivation.

    Conclusion: Double and triple combination regimens that target induction of the same death mechanism with reduced dosage of each drug could potentially be clinically beneficial in reducing dose-related toxicities.

  15. Sheikh NA, Ching DLC, Khan I, Sakidin HB, Jamil M, Khalid HU, et al.
    Sci Rep, 2021 Aug 09;11(1):16117.
    PMID: 34373521 DOI: 10.1038/s41598-021-95528-z
    The present work used fractional model of Casson fluid by utilizing a generalized Fourier's Law to construct Caputo Fractional model. A porous medium containing nanofluid flowing in a channel is considered with free convection and electrical conduction. A novel transformation is applied for energy equation and then solved by using integral transforms, combinedly, the Fourier and Laplace transformations. The results are shown in form of Mittag-Leffler function. The influence of physical parameters have been presented in graphs and values in tables are discussed in this work. The results reveal that heat transfer increases with increasing values of the volume fraction of nanoparticles, while the velocity of the nanofluid decreases with the increasing values of volume fraction of these particles.
  16. Settar S. Keream, Ahmed N Abdalla, Mohd Razali Bin Daud
    MyJurnal
    A new Nonlinear Dynamic Inverse (NDI) method is proposed to minimise the ripple torque in an induction motor. This method is based on field oriented with space vector pulse width modulation (SVPWM). The nonlinear dynamic inverse controller cancelled a non-desirable response of the induction motor and enhancing the performance. This cancellation attempts by careful nonlinear algebraic equations. First, a mathematical model of induction motor and decoupling between two inputs have achieved. Then the desired new dynamic is derived from implementing the proposed nonlinear dynamic inverse controller (NDIC) technique that reserves some benefits such as fast torque control, minimum ripple torque, and fast speed response. Also, the proposed method significantly reduced the torque ripple which is the major concerns of the classical hysteresis-based in direct torque control (DTC) and feedback linearization control (FLC) scheme and have an effect on the stator current distortion. Finally, the simulation results with MATLAB/Simulink achieved for a 2-hp induction motor (IM) drive. The results are verification proved that the proposed (NDI-SVPWM) system achieves smaller torque ripple about 0.4% and faster torque response than the conventional SVM-based on proportional integral (PI-DTC) method.
  17. Sarfaraz S, Ahmed N, Abbasi MS, Sajjad B, Vohra F, Al-Hamdan RS, et al.
    Work, 2020;67(4):791-798.
    PMID: 33325429 DOI: 10.3233/WOR-203332
    BACKGROUND: The aim of this study was to evaluate the self-perceived competency (FSPC) of medical faculty in E-Teaching and support received during the COVID-19 pandemic.

    METHODS: An online well-structured and validated faculty self-perceived competency questionnaire was used to collect responses from medical faculty. The questionnaire consisted of four purposely build sections on competence in student engagement, instructional strategy, technical communication and time management. The responses were recorded using a Likert ordinal scale (1-9). The Questionnaire was uploaded at www.surveys.google.com and the link was distributed through social media outlets and e-mails. Descriptive statistics and Independent paired t-test were used for analysis and comparison of quantitative and qualitative variables. A p-value of ≤0.05 was considered statistically significant.

    RESULTS: A total of 738 responses were assessed. Nearly 54% (397) participants had less than 5 years of teaching experience, 24.7% (182) had 6-10 years and 11.7% (86) had 11-15 years teaching expertise. 75.6% (558) respondents have delivered online lectures during the pandemic. Asynchronous methods were used by 61% (450) and synchronous by 39% (288) of participants. Moreover, 22.4% (165) participants revealed that their online lectures were evaluated by a structured feedback from experts, while 38.3% participants chose that their lectures were not evaluated. A significant difference (p 

  18. Saleem MKM, Lal A, Ahmed N, Abbasi MS, Vohra F, Abduljabbar T
    PeerJ, 2023;11:e14860.
    PMID: 36908817 DOI: 10.7717/peerj.14860
    BACKGROUND: Salivary disturbance is associated with patients who either have an active coronavirus disease 2019 (COVID-19) or have recovered from coronavirus infection along with loss of taste sensation. In addition, COVID-19 infection can drastically compromise quality of life of individuals.

    OBJECTIVE: This study aimed to analyze xerostomia, ageusia and the oral health impact in coronavirus disease-19 patients utilizing the Xerostomia Inventory scale-(XI) and the Oral Health Impact Profile-14.

    METHODS: In this cross-sectional survey-based study, data was collected from 301 patients who suffered and recovered from COVID-19. Using Google Forms, a questionnaire was developed and circulated amongst those who were infected and recovered from coronavirus infection. The Xerostomia Inventory (XI) and Oral Health Impact Profile-14 were used to assess the degree and quality of life. A paired T-test and Chi-square test were used to analyze the effect on xerostomia inventory scale-(XI) and OHIP-14 scale scores. A p-value of 0.05 was considered as statistically significant.

    RESULTS: Among 301 participants, 54.8% were females. The prevalence of xerostomia in participants with active COVID-19 disease was 39.53% and after recovery 34.88%. The total OHIP-14 scores for patients in the active phase of infection was 12.09, while 12.68 in recovered patients. A significant difference was found between the mean scores of the xerostomia inventory scale-11 and OHIP-14 in active and recovered COVID patients.

    CONCLUSION: A higher prevalence of xerostomia was found in COVID-19 infected patients (39.53%) compared to recovered patients (34.88%). In addition, more than 70% reported aguesia. COVID-19 had a significantly higher compromising impact on oral function of active infected patients compared to recovered patients.

  19. Rizvi A, Hussain N, Anjum AA, Ahmed N, Naeem A, Khan M, et al.
    J Virol Methods, 2022 Feb;300:114379.
    PMID: 34826516 DOI: 10.1016/j.jviromet.2021.114379
    Foot-and-mouth disease (FMD) is a highly infectious disease of cattle and other cloven-hoofed animals, causing huge economic losses annually worldwide. This disease is endemic in Pakistan where the serotypes of the foot-and-mouth disease virus (FMDV) are A, O and ASIA-1. At present, trivalent FMDV vaccines are being used to prevent FMD but the current production process is laborious and is unable to fulfill the needs of the meat and dairy industries. To meet the vaccine needs of Pakistan, the conventional method of using adherent cell lines to produce the vaccine could be replaced by suspension cell cultures which produce higher yields in less time and less volume. Therefore, the aim of this study was to investigate and optimize some of the factors that affect viable cell density and subsequent virus yield. The relationship between the yield of the 146S fraction and the TCID50 of the virus preparations obtained was also evaluated as a mean to control and check the quality of the vaccine product. The results provided optimized conditions for vaccine production using cell suspensions and showed that there was a linear relationship between TCID50 and 146S fraction yield. Either TCID50 or the 146S fraction yield, or both could be used as parameters for quality monitoring during vaccine production. Using TCID50 reduced the number of steps involved in virus production while measuring 146S fraction yield was useful for quality control. However, more studies are required to evaluate the relative effectiveness of vaccines produced by virus cultures using either TCID50 or 146S fraction as quality monitoring tools.
  20. Rifai D, Abdalla AN, Ali K, Razali R
    Sensors (Basel), 2016;16(3):298.
    PMID: 26927123 DOI: 10.3390/s16030298
    Non-destructive eddy current testing (ECT) is widely used to examine structural defects in ferromagnetic pipe in the oil and gas industry. Implementation of giant magnetoresistance (GMR) sensors as magnetic field sensors to detect the changes of magnetic field continuity have increased the sensitivity of eddy current techniques in detecting the material defect profile. However, not many researchers have described in detail the structure and issues of GMR sensors and their application in eddy current techniques for nondestructive testing. This paper will describe the implementation of GMR sensors in non-destructive testing eddy current testing. The first part of this paper will describe the structure and principles of GMR sensors. The second part outlines the principles and types of eddy current testing probe that have been studied and developed by previous researchers. The influence of various parameters on the GMR measurement and a factor affecting in eddy current testing will be described in detail in the third part of this paper. Finally, this paper will discuss the limitations of coil probe and compensation techniques that researchers have applied in eddy current testing probes. A comprehensive review of previous studies on the application of GMR sensors in non-destructive eddy current testing also be given at the end of this paper.
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