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Fulltext Fabrication and characterization of a pH-sensitive intelligent film incorporating dragon fruit skin extract

Azlim NA, Mohammadi Nafchi A, Oladzadabbasabadi N, Ariffin F, Ghalambor P, Jafarzadeh S, et al.

Food Sci Nutr, 2022 Feb;10(2):597-608.
PMID: 35154695 DOI: 10.1002/fsn3.2680

A novel intelligent pH-sensing indicator based on gelatin film and anthocyanin extracted from dragon fruit skin (Hylocereus polyrhizus) (DFSE) as a natural dye was developed to monitor food freshness by the casting method. Anthocyanin content of DFSE was 15.66 ± 1.59 mg/L. Dragon fruit bovine gelatin films were characterized by Fourier transform infrared spectroscopy (FTIR) and observed by a scanning electron microscope (SEM). Moisture content, mechanical properties, water solubility, water vapor permeability (WVP), light transmittance, color, and pH-sensing evaluations were evaluated for potential application. FTIR spectroscopy revealed that the extracted anthocyanin could interact with the other film components through hydrogen bonds. When the extract was added, films showed a smooth and clear surface as observed by SEM. The addition of anthocyanin increased the moisture content, thickness, and water solubility of the films, but decreased the WVP and light transmittance of films. Also, the incorporation of 15% v/v DFSE decreased the tensile strength from 17.04 to 12.91 MPa, increasing the elongation at break from 91.19% to 107.86%. The films showed higher ΔE with increasing DFSE content, which indicated that the film had good color variability. A significant difference in the color of the films was observed with exposure to different pH buffer solutions. The findings demonstrated that gelatin film incorporated with DFSE could be used as a visual indicator of pH variations to monitor the freshness of foods during storage time.
Endoscopic sphincterotomy with balloon dilatation versus sphincterotomy alone for common bile duct stones removal: a randomised controlled trial

Ooi JS, Ikhwan SM, Azem Fathi MA, Leow VM, Syed Hassan AZ

Med J Malaysia, 2024 Mar;79(2):133-140.
PMID: 38553916

INTRODUCTION: Endoscopic sphincterotomy (EST) plus endoscopic papillary large balloon dilatation (EPLBD) has been reported as a valid alternative to EST alone in removing common bile duct (CBD) stone. The aim of this study is to compare efficacy, and safety of these two groups of patients in removing CBD stone in Hospital Universiti Sains Malaysia (HUSM).
MATERIALS AND METHODS: This is a prospective single centre randomised single blinded comparative study conducted in HUSM. The primary endpoints for this study are the overall complete stone clearance rate and complication rate, while the secondary outcome for this study are duration of procedure and rate of usage of adjunct methods. Objective data analysis is conducted using independent sample t-test and chi-squared test.
RESULTS: A total of 66 patients underwent endoscopic retrograde cholangiopancreatography (ERCP) for choledocholithiasis which is CBD stone. 34 patients were allocated to EST plus EPLBD arm (n=34), and 32 patients were in EST alone arm (n=32) using randomisation method. For intention to treat, patients from EST alone arm that unable to achieve complete stone clearance will be switched to EST plus EPLBD arm. The overall complete stone removal rate for both groups were comparable (EST plus EPLDB: 100% versus EST alone: 93.8%; p= 0.139). The two patients from EST alone group (6.2%) that unable to achieve complete stone clearance were converted to EST plus EPLBD group for intention to treat and able to achieve complete stone clearance by EST plus EPLBD. For procedural time, both arms are comparable as well (EST plus EPLDB: 15.8 minutes vs EST alone: 15.5 minutes; p= 0.860). Complications such as pancreatitis occurred in one patient in EST plus EPLBD arm (EST plus EPLDB: 2.9 % vs EST alone: 0 %; p= 0.328), and bleeding occurred in one patient in EST alone arm (EST plus EPLDB: 0 % vs EST alone: 3.1 %; p= 0.299) , but it is not statistically significant. No perforation or cholangitis complication occurred in both groups. No adjunct usage was observed in both groups.
CONCLUSION: In this study with limited sample size, both EST plus EPLBD and EST alone are effective and has comparable procedural time in removing CBD stone. Even though both methods are equally effective, EPLBD plus EST is an alternative solution if complete stone clearance is unable to achieve via EST alone.
Fulltext A prospective study of tracheal intubation in an academic emergency department in Malaysia

Fathil SM, Mohd Mahdi SN, Che'man Z, Hassan A, Ahmad Z, Ismail AK

Int J Emerg Med, 2010;3(4):233-7.
PMID: 21373289 DOI: 10.1007/s12245-010-0201-0

BACKGROUND: Airway management is an important part of the management of the critically ill and injured patients in the Emergency Department (ED). Numerous studies from developed countries have demonstrated the competency of emergency doctors in intubation. To date there have been no published data on intubations performed in EDs in Malaysia.
METHODS: Data on intubations from 7 August 2007 till 28 August 2008 were prospectively collected.
RESULTS: There were 228 intubations included in the study period. Cardiopulmonary arrest was the main indication for intubation (35.5%). The other indications were head injury (18.4%), respiratory failure (15.4%), polytrauma (9.6%) and cerebrovascular accident (7.0%). All of the 228 patients were successfully intubated. Rapid sequence intubation (RSI) was the most frequent method (49.6%) of intubation. A total of 223 (97.8%) intubations were done by ED personnel. In 79.8% of the cases, intubations were successfully performed on the first attempt. Midazolam was the most common induction agent used (97 patients), while suxamethonium was the muscle relaxant of choice (109 patients). There were 34 patients (14.9%) with 38 reported immediate complications. The most common complication was oesophageal intubation.
CONCLUSION: Emergency Department UKMMC personnel have a high competency level in intubation with an acceptable complication rate. RSI was the most common method for intubation.
KEYWORDS: Airway; Intubation; Orotracheal intubation; Rapid sequence intubation
Fulltext Unmasking the challenges in ideological and political education in China: A thematic review

Ouyang S, Zhang W, Xu J, Mat Rashid A, How SP, Bin Hassan A

Heliyon, 2024 Apr 30;10(8):e29176.
PMID: 38644869 DOI: 10.1016/j.heliyon.2024.e29176

China's distinctive educational approach, particularly its emphasis on ideological and political education, has garnered considerable academic attention for its impact on shaping individual values, fostering citizenship, and maintaining social stability. Despite the Chinese government's prioritization of ideological and political education, academic research in this field appears constrained, with existing studies predominantly focusing on normative and descriptive aspects. Normative research delineates how ideological and political education should be executed, while descriptive research illustrates its practical implementation. The effectiveness of these approaches is significantly diminished if they are not adequately interconnected-when only the current reality is explained without providing tools for improvement or when prescribed steps for improvement lack a basis in specific contexts. This paper conducts a comprehensive review of research on ideological and political education using ATLAS. ti 9 for thematic analysis. The review aims to unveil the intricate landscape of current research in China and address key questions: What are the primary trends in the literature on ideological and political education between 2021 and July 2023? What challenges does ideological and political education face? Through a direct exploration of these issues, this paper seeks to optimize the ideological and political education system, elevate its adaptability and effectiveness, and open avenues for research, fostering a more dynamic, inclusive, and resilient development of ideological and political education.
Influence of bioaugmented fungi on tolerance, growth and phytoremediation ability of Prosopis juliflora Sw. DC in heavy metal-polluted landfill soil

Hassan A, Hamid FS, Pariatamby A, Ossai IC, Ahmed A, Barasarathi J, et al.

Environ Sci Pollut Res Int, 2024 Apr;31(19):28671-28694.
PMID: 38561536 DOI: 10.1007/s11356-024-33018-1

The research aimed to determine the influence of endophytic fungi on tolerance, growth and phytoremediation ability of Prosopis juliflora in heavy metal-polluted landfill soil. A consortium of 13 fungal isolates as well as Prosopis juliflora Sw. DC was used to decontaminate heavy metal-polluted landfill soil. Enhanced plant growth (biomass and root and shoot lengths) and production of carotenoids, chlorophyll and amino acids L-phenylalanine and L-leucine that are known to enhance growth were found in the treated P. juliflora. Better accumulations of heavy metals were observed in fungi-treated P. juliflora over the untreated one. An upregulated activity of peroxidase, catalase and ascorbate peroxidase was recorded in fungi-treated P. juliflora. Additionally, other metabolites, such as glutathione, 3,5,7,2',5'-pentahydroxyflavone, 5,2'-dihydroxyflavone and 5,7,2',3'-tetrahydroxyflavone, and small peptides, which include Lys Gln Ile, Ser Arg Ala, Asp Arg Gly, Arg Ser Ser, His His Arg, Arg Thr Glu, Thr Arg Asp and Ser Pro Arg, were also detected. These provide defence supports to P. juliflora against toxic metals. Inoculating the plant with the fungi improved its growth, metal accumulation as well as tolerance against heavy metal toxicity. Such a combination can be used as an effective strategy for the bioremediation of metal-polluted soil.
Factors Influencing Tooth Sensitivity: Insights From the Hospital Universiti Sains Malaysia Using Bootstrap-Enhanced Ordinal Regression

Mat Lazin MA, Wan Zainon WN, Humayun A, Madawana AM, Hassan A, Zhang Y, et al.

Cureus, 2024 Jul;16(7):e64641.
PMID: 39149669 DOI: 10.7759/cureus.64641

Introduction Tooth sensitivity, or dentin hypersensitivity (DH), is characterized by sharp, sudden pain in response to stimuli such as cold, heat, sweet, or acidic foods and drinks. In Malaysia, there is limited understanding of the epidemiological aspects of tooth sensitivity, necessitating focused research. The condition results from the exposure of dentinal tubules transmitting stimuli to nerves within the pulp, with contributing factors including gingival recession, enamel erosion, and periodontal disease. This study aims to investigate the factors associated with tooth sensitivity among patients at the Hospital Universiti Sains Malaysia (USM) using advanced statistical methods. Methods This study employed a computational research design to develop an ordinal regression and bootstrap methodology using the RStudio software (Posit PBC, Boston, MA) to analyze secondary data from the Hospital Universiti Sains Malaysia. Six variables were analyzed: tooth wear severity, patient's age, gender, smoking status, alcohol status, and type of toothbrush. The study was conducted in three phases: 1) the development of an ordinal regression model, 2) the development of algorithms for ordinal regression and bootstrap method, and 3) validation using tooth sensitivity data. Results The analysis revealed that the replication with 1000 samples provided the most precise estimates with small standard errors (SE) and consistently significant effects across variables. Tooth sensitivity was influenced by age, toothpaste type, toothbrush type, and brushing frequency. Conclusion The study highlights the importance of considering multiple variables such as age, toothpaste type, toothbrush type, and brushing frequency in understanding tooth sensitivity. The combined ordinal regression and bootstrap technique significantly improved the model's accuracy, providing valuable insights for dental health professionals. These findings underscore the need for specific guidelines on oral hygiene practices to manage and reduce the risk of tooth sensitivity.
Pharmacological Action and Research Progress of Taraxasterol

Zhang Y, BinShaari R, Nawi MABA, Bin Hassan A, Cui C

Curr Pharm Biotechnol, 2024;25(14):1767-1777.
PMID: 38178677 DOI: 10.2174/0113892010276692231220103636

Primarily sourced from Asteraceae family herbs such as the Dandelion, Taraxasterol is a pentacyclic triterpenoid lauded for its extensive biological functionalities. Its therapeutic potency is demonstrated in various disease models, encompassing enteritis, arthritis, acute hepatic injury, and pneumonia. Scientific literature underscores its anti-inflammatory, antioxidant, and antineoplastic attributes. The primary aim of this study is to thoroughly explore the diseasemodulating mechanisms and effects of taraxasterol. We endeavor to provide an exhaustive review of the experimental subjects, intervention components, distinct action modalities, contributing factors, and protein pathway expressions associated with taraxasterol, systematically represented via diagrams and tables. Such a schematic representation encourages a continued academic dialogue concerning taraxasterol's pharmacological characteristics. This review is envisioned as a practical guide for the selection of experimental subjects and methodologies in prospective research. It is intended to further illuminate taraxasterol's pharmacodynamics, thereby offering theoretical and empirical justification for its clinical application.
Fulltext The Role of Alternative Medicine in Managing Type 2 Diabetes: A Comprehensive Review

McBenedict B, Orfao AL, Goh KS, Yau RCC, Alphonse B, Machado Lima J, et al.

Cureus, 2024 Jun;16(6):e61965.
PMID: 38978922 DOI: 10.7759/cureus.61965

Diabetes, a chronic metabolic disorder marked by elevated blood glucose levels, is increasingly prevalent globally, significantly impacting health-related quality of life. Type 2 diabetes (T2DM), characterized by insulin resistance and inadequate insulin production, presents a substantial public health challenge, necessitating comprehensive management strategies. Conventional treatments, including lifestyle modifications and pharmacotherapy, are essential for glycemic control and preventing complications. However, adherence to these treatments is often limited, highlighting the need for alternative strategies. Complementary and alternative medicine (CAM) offers potential cost-effective and accessible approaches for managing T2DM. Key herbal remedies like cinnamon, fenugreek, and bitter melon, along with dietary supplements like chromium, magnesium, and vanadium, have shown promise in glycemic control. Mind-body therapies, including yoga, tai chi, and meditation, contribute to improved hemoglobin A1c and fasting blood glucose levels. Research supports the integration of CAM with conventional therapies, demonstrating enhanced clinical efficacy and reduced economic burden. However, challenges such as standardization, quality control, and potential risks of herbal medicines need careful consideration. Regulatory frameworks and ethical considerations are essential to ensure patient safety and informed decision-making. Patient education and effective communication between healthcare providers and patients are crucial for integrating CAM into diabetes management. Empowerment-based interventions and collaborative approaches can enhance self-management skills and clinical outcomes. Overall, integrating CAM with conventional treatments offers a holistic approach to managing T2DM, potentially improving patient outcomes and reducing healthcare costs.
Diverse human rhinoviruses A and C from children with respiratory infections in Kuala Lumpur, Malaysia

Chan YF, Jafar FL, Nathan AM, de Bruyne JA, Hassan A, Nor'e SS, et al.

J Infect, 2012 Jun;64(6):633-6.
PMID: 22425558 DOI: 10.1016/j.jinf.2012.03.011
Exploring the effect of cellulose nanowhiskers isolated from oil palm biomass on polylactic acid properties

Haafiz MK, Hassan A, Khalil HP, Fazita MR, Islam MS, Inuwa IM, et al.

Int J Biol Macromol, 2016 Apr;85:370-8.
PMID: 26772914 DOI: 10.1016/j.ijbiomac.2016.01.004

In this work, polylactic acid (PLA) reinforced cellulose nanowhiskers (CNW) were prepared through solution casting technique. The CNW was first isolated from oil palm empty fruit bunch microcrystalline cellulose (OPEFB-MCC) by using 64% H2SO4 and was designated as CNW-S. The optical microscopy revealed that the large particle of OPEFB-MCC has been broken down by the hydrolysis treatment. The atomic force microscopy confirmed that the CNW-S obtained is in nanoscale dimension and appeared in individual rod-like character. The produced CNW-S was then incorporated with PLA at 1, 3, and 5 parts per hundred (phr) resins for the PLA-CNW-S nanocomposite production. The synthesized nanocomposites were then characterized by a mean of tensile properties and thermal stability. Interestingly to note that incorporating of 3 phr/CNW-S in PLA improved the tensile strength by 61%. Also, CNW-S loading showed a positive impact on the Young's modulus of PLA. The elongation at break (Eb) of nanocomposites, however, decreased with the addition of CNW-S. Field emission scanning electron microscopy and transmission electron microscopy revealed that the CNW-S dispersed well in PLA at lower filler loading before it started to agglomerate at higher CNW-S loading (5phr). The DSC analysis of the nanocomposites obtained showed that Tg,Tcc and Tm values of PLA were improved with CNW-S loading. The TGA analysis however, revealed that incopreated CNW-S in PLA effect the thermal stability (T10,T50 and Tmax) of nanocomposite, where it decrease linearly with CNW-S loading.
Fulltext Dataset for the morphological and erythrocytes parameters of Clarias gariepinus, Pangasianodon hypophthalmus, and their reciprocal hybrids

Okomoda VT, Koh ICC, Hassan A, Oladimeji AS, Ikhwanuddin M, Abol-Munafi AB, et al.

Data Brief, 2020 Oct;32:106151.
PMID: 32904264 DOI: 10.1016/j.dib.2020.106151

Discrimination of different fishes can be done through different means which includes morphological appearance. When two fishes are successfully hybridized, they produce progenies that have shared morphology between their pure parent, hence, making morphometric characterization an important aspect of hybrid discrimination. However, erythrocyte characterization is also a simpler method for characterization. The dataset presented in this article represents the traditional morphological data, truss network data and erythrocyte data of pure and novel hybrids from reciprocal crosses of African catfish Clarias gariepinus and Asian catfish Pangasianodon hypophthalmus. Breeding of the broodstocks was done to produce pure and hybrid progenies which were maintained for a period of four to six months. Based on the cross combinations and morphotypes, traditional measurement of twenty-five morphological characters and five meristic counts were recorded. Thereafter pictures of the different fish groups were used to determine values of thirty-six distances between ten landmark points. The morphological abnormality of the hybrids at market size is also presented in this data article for the very first time. Blood was then collected from the caudal peduncle of ten fish per group and smeared on a slide for observation under a compound microscope (at 100 × magnification). Data gotten included erythrocytes parameters such as cell major axis, cell minor axis, nucleus major axis, nucleus minor axis cell area, nucleus area, cell volume, and nucleus volume. Data recording was through the Microsoft excel spreadsheet; which was also used to process the data to get the exclusive ranges of values for paired progenies. The data as presented is associated with the research article "Morphological characterization of the progenies of pure and reciprocal crosses of Pangasianodon hypophthalmus (Sauvage, 1878) and Clarias gariepinus (Burchell, 1822)" [1]. The dataset presented in this article can be used for easy identification of the novel hybrid progenies of the African Catfish and Asian Catfish.
Fulltext Cluster Analysis Evaluating PM2.5, Occupation Risk and Mode of Transportation as Surrogates for Air-pollution and the Impact on Lung Cancer Diagnosis and 1-Year Mortality

Abdul Wahab S, Hassan A, Latif MT, Vadiveel Y, Jeyabalan T, Soo CI, et al.

Asian Pac J Cancer Prev, 2019 07 01;20(7):1959-1965.
PMID: 31350951 DOI: 10.31557/APJCP.2019.20.7.1959

Objective: Epidemiological studies have reported the close relationship between risk for lung cancers and air pollution
in particular, for non-smoking related lung cancers. However, most studies used residential address as proxies which may
not estimate accurately an individual’s air pollution exposure. Therefore, the aim of this study was to identify risk factors
such as occupation and mode of transportation associated with lung cancer diagnosis and death. Methods: Subjects
with lung cancer (n=514) were evaluated both by chart reviews for clinical data and interviews to determine residential
address for ten years, main occupation and main mode of transportation. Annual particulate matter with diameter size
less than 2.5 micrometre (PM2.5) concentration were calculated based on particulate matter with diameter size less than
10 micrometre (PM10) data recorded by Malaysian Department of Environment. Logistic regression analysis, cluster
analysis and the Cox regression analysis were performed to the studied variables. Results: This study concurred with
previous studies that lung adenocarcinoma were diagnosed in predominantly younger, female non-smokers compared
to the other types of lung cancers. Lung adenocarcinoma subjects had annual PM2.5 that was almost twice higher than
squamous cell carcinoma, small cell carcinoma and other histological subtypes (p=0.024). Independent of smoking,
the κ -means cluster analysis revealed two clusters in which the high risk cluster involves occupation risk with air
pollution of more than four hours per day, main transportation involving motorcycle and trucks and mean annual PM2.5
concentration of more than 30 based on residential address for more than ten years. The increased risk for the high-risk
cluster was more than five times for the diagnosis of lung adenocarcinoma (OR=5.69, 95% CI=3.14-7.21, p<0.001).
The hazard ratio for the high-risk cluster was 3.89 (95% CI=2.12-4.56, p=0.02) for lung adenocarcinoma mortality at
1 year. Conclusion: High-risk cluster including PM2.5, occupation risk and mode of transportation as surrogates for
air-pollution exposure was identified and highly associated with lung adenocarcinoma diagnosis and 1-year mortality.
Fulltext Mechanical and Thermal Properties of Montmorillonite-Reinforced Polypropylene/Rice Husk Hybrid Nanocomposites

Majeed K, Ahmed A, Abu Bakar MS, Indra Mahlia TM, Saba N, Hassan A, et al.

Polymers (Basel), 2019 Sep 25;11(10).
PMID: 31557811 DOI: 10.3390/polym11101557

In recent years, there has been considerable interest in the use of natural fibers as potential reinforcing fillers in polymer composites despite their hydrophilicity, which limits their widespread commercial application. The present study explored the fabrication of nanocomposites by melt mixing, using an internal mixer followed by a compression molding technique, and incorporating rice husk (RH) as a renewable natural filler, montmorillonite (MMT) nanoclay as water-resistant reinforcing nanoparticles, and polypropylene-grafted maleic anhydride (PP-g-MAH) as a compatibilizing agent. To correlate the effect of MMT delamination and MMT/RH dispersion in the composites, the mechanical and thermal properties of the composites were studied. XRD analysis revealed delamination of MMT platelets due to an increase in their interlayer spacing, and SEM micrographs indicated improved dispersion of the filler(s) from the use of compatibilizers. The mechanical properties were improved by the incorporation of MMT into the PP/RH system and the reinforcing effect was remarkable as a result of the use of compatibilizing agent. Prolonged water exposure of the prepared samples decreased their tensile and flexural properties. Interestingly, the maximum decrease was observed for PP/RH composites and the minimum was for MMT-reinforced and PP-g-MAH-compatibilized PP/RH composites. DSC results revealed an increase in crystallinity with the addition of filler(s), while the melting and crystallization temperatures remained unaltered. TGA revealed that MMT addition and its delamination in the composite systems improved the thermal stability of the developed nanocomposites. Overall, we conclude that MMT nanoclay is an effective water-resistant reinforcing nanoparticle that enhances the durability, mechanical properties, and thermal stability of composites.
Environmental effects on the oxygen consumption rate in juvenile Epinephelus fuscoguttatus (Forsskal, 1775)

Okomoda VT, Mithun S, Chatterji A, Effendy MAW, Oladimeji AS, Abol-Munafi AB, et al.

Fish Physiol Biochem, 2020 Aug;46(4):1497-1505.
PMID: 32378001 DOI: 10.1007/s10695-020-00807-7

This study was designed to optimize the culture conditions of juvenile Epinephelus fuscoguttatus (Forsskål, 1775) under laboratory conditions. To this effect, the rate of oxygen consumption was monitored as an index of stress under different temperature, salinity, pH, photoperiod, and urea concentrations. The result obtained after 12 h of exposure suggests the preference of the juvenile E. fuscoguttatus to a temperature range of 15-25 °C and salinity of 30 ppt. Based on this study, temperature was found to be the most lethal as 100% mortality was observed after 6 h in fish exposure to temperatures above the optimal (≥ 30 °C). However, the oxygen consumption rate was similar under the different pH, photoperiod, and urea concentration tested. It was concluded that water temperature was most critical in terms of respiration physiology of the juvenile E. fuscoguttatus given the range and levels of environmental factors tested in this study.
Dengue envelope domain III-peptide binding analysis via tryptophan fluorescence quenching assay

Baharuddin A, Amir Hassan A, Othman R, Xu Y, Huang M, Ario Tejo B, et al.

Chem Pharm Bull (Tokyo), 2014;62(10):947-55.
PMID: 25273053

In the efforts to find an anti-viral treatment for dengue, a simple tryptophan fluorescence-screening assay aimed at identifying dengue domain III envelope (EIII) protein inhibitors was developed. Residue Trp391 of EIII was used as an intrinsic probe to monitor the change in fluorescence of the tryptophan residue upon binding to a peptide. The analysis was based on the electron excitation at 280 nm and fluorescence emission at 300-400 nm of EIII, followed by quenching of fluorescence in the presence of potential peptidic inhibitors coded DS36wt, DS36opt, DN58wt and DN58opt. The present study found that the fluorescence of the recombinant EIII was quenched following the binding of DS36opt, DN58wt and DN58opt in a concentration-dependent manner. Since the λmax for emission remained unchanged, the effect was not due to a change in the environment of the tryptophan side chain. In contrast, a minimal fluorescence-quenching effect of DS36wt at 20 and 40 µM suggested that the DS36wt does not have any binding ability to EIII. This was supported by a simple native-page gel retardation assay that showed a band shift of EIII domain when incubated with DS36opt, DN58wt and DN58opt but not with DS36wt. We thus developed a low-cost and convenient spectrophotometric binding assay for the analysis of EIII-peptide interactions in a drug screening application.
Conformational and energy evaluations of novel peptides binding to dengue virus envelope protein

Amir-Hassan A, Lee VS, Baharuddin A, Othman S, Xu Y, Huang M, et al.

J Mol Graph Model, 2017 06;74:273-287.
PMID: 28458006 DOI: 10.1016/j.jmgm.2017.03.010

Effective novel peptide inhibitors which targeted the domain III of the dengue envelope (E) protein by blocking dengue virus (DENV) entry into target cells, were identified. The binding affinities of these peptides towards E-protein were evaluated by using a combination of docking and explicit solvent molecular dynamics (MD) simulation methods. The interactions of these complexes were further investigated by using the Molecular Mechanics-Poisson Boltzmann Surface Area (MMPBSA) and Molecular Mechanics Generalized Born Surface Area (MMGBSA) methods. Free energy calculations of the peptides interacting with the E-protein demonstrated that van der Waals (vdW) and electrostatic interactions were the main driving forces stabilizing the complexes. Interestingly, calculated binding free energies showed good agreement with the experimental dissociation constant (Kd) values. Our results also demonstrated that specific residues might play a crucial role in the effective binding interactions. Thus, this study has demonstrated that a combination of docking and molecular dynamics simulations can accelerate the identification process of peptides as potential inhibitors of dengue virus entry into host cells.
Optimization of ultraviolet irradiation of Clarias gariepinus (Burchell, 1822) eggs for androgen production

Okomoda VT, Nursyaza HJ, Samuel IO, Hassan A, Oladimeji AS, Abol-Munafi AB, et al.

Zygote, 2021 Jun;29(3):223-228.
PMID: 33446295 DOI: 10.1017/S0967199420000829

The optimum distance and duration of ultraviolet (UV) irradiation for the complete inactivation of African catfish Clarias gariepinus egg nucleus was investigated in this study. The UV light was suspended above the unfertilized eggs at four distances (5, 10, 20 and 30 cm) and for five durations (1, 2, 3, 4 and 5 min). Then, the irradiated eggs were activated with sperm from diploid C. gariepinus and cold shocked at 5°C for 5 min just moments before cell cleavage. Ploidy analysis was performed using karyotype chromosome counting. The results obtained suggested that the further the distance, the better the hatchability rate, however prolonged duration seemed to significantly reduced hatchability. All treatments with surviving progenies at the end of the study showed evidence of successfully diploid gynogen (2n = 56) induction at different percentages. However, the optimal protocol that gave a moderately high hatchability/survival rate and completely induced gynogens was exposure of the eggs to UV irradiation at 20 cm for 1 min. It was concluded that the distance and duration of UV irradiation affects gynogenetic induction in African catfish C. gariepinus.
Study of the D-- phenotype reveals erythrocyte membrane alterations in the absence of RHCE

Flatt JF, Musa RH, Ayob Y, Hassan A, Asidin N, Yahya NM, et al.

Br J Haematol, 2012 Jul;158(2):262-273.
PMID: 22571328 DOI: 10.1111/j.1365-2141.2012.09149.x

Red cells with the D-- phenotype do not express the RHCE protein because of mutations in both alleles of the RHCE gene. At present, little is known of the effect this has on the normal function of erythrocytes. In this study a group of five families belonging to a nomadic tribe in Malaysia were identified as carriers of the D-- haplotype. Analysis of homozygous individuals' genomic DNA showed two separate novel mutations. In four of the families, RHCE exons 1, 9 and 10 were present, while the 5th family possessed RHCE exons 1-3 and 10. Analysis of cDNA revealed hybrid transcripts, suggesting a gene conversion event with RHD, consistent with previously reported D-- mutations. Immunoblotting analysis of D-- erythrocyte membrane proteins found that Rh-associated glycoprotein (RHAG) migrates with altered electrophoretic mobility on sodium dodecyl sulphate polyacrylamide gel electrophoresis, consistent with increased glycosylation. Total amounts of Rh polypeptide in D-- membranes were comparable with controls, indicating that the exalted D antigen displayed by D-- red cells may be associated with altered surface epitope presentation. The adhesion molecules CD44 and CD47 are significantly reduced in D--. Together these results suggest that absence of RHCE polypeptide alters the structure and packing of the band 3/Rh macrocomplex.
Fulltext Phylogenetic analysis of human metapneumovirus among children with acute respiratory infections in Kuala Lumpur, Malaysia

Nor'e SS, Sam IC, Mohamad Fakri EF, Hooi PS, Nathan AM, de Bruyne JA, et al.

Trop Biomed, 2014 Sep;31(3):562-6.
PMID: 25382484 MyJurnal

Human metapneumovirus (HMPV) is a recently discovered cause of viral respiratory infections. We describe clinical and molecular epidemiology of HMPV cases diagnosed in children with respiratory infection at University of Malaya Medical Centre, Kuala Lumpur, Malaysia. The prevalence rate of HMPV between 2010 and 2012 was 1.1%, and HMPV contributed 6.5% of confirmed viral respiratory infections. The HMPV patients had a median age of 1.6 years, and a median hospital admission of 4 days. The most common clinical presentations were fever, rhinitis, pneumonia, vomiting/diarrhoea, and bronchiolitis. Based on the partial sequences of F fusion gene from 26 HMPV strains, 14 (54%) were subgenotype A2b, which was predominant in 2010; 11 (42%) were subgenotype B1, which was predominant in 2012; and 1 (4%) was subgenotype A2a. Knowledge of the circulating subgenotypes in Malaysia, and the displacement of predominant subgenotypes within 3 years, is useful data for future vaccine planning.
Design, synthesis, in vitro Evaluation and docking studies on dihydropyrimidine-based urease inhibitors

Iftikhar F, Ali Y, Ahmad Kiani F, Fahad Hassan S, Fatima T, Khan A, et al.

Bioorg Chem, 2017 10;74:53-65.
PMID: 28753459 DOI: 10.1016/j.bioorg.2017.07.003

In our previous report, we have identified 3,4-dihydropyrimidine scaffold as promising class of urease inhibitor in a structure based virtual screen (SBVS) experiment. In present study, we attempted to optimize the scaffold by varying C-5 substituent. The elongation of the C-5 chain was achieved by the reaction of C-5 ester with hydrazine leading to C-5 carbohydrazides which were further used as building blocks for the synthesis of fifteen new compounds having diverse moieties. A significantly higher in vitro urease inhibitory activity with IC50 values in submicromolar range was observed for semithiocarbazide derivatives (4a-c, 0.58-0.79µM) and isatin Schiff base derivative 5a (0.23µM). Docking analysis suggests that the synthesized compounds were anchored well in the catalytic site and extending to the entrance of binding pocket and thus restrict the mobility of the flap by interacting with its key amino acid residues. The overall results of urease inhibition have shown that these compounds can be further optimized and developed as lead urease inhibitors.

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