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Fulltext FabV/Triclosan Is an Antibiotic-Free and Cost-Effective Selection System for Efficient Maintenance of High and Medium-Copy Number Plasmids in Escherichia coli

Ali SA, Chew YW

PLoS One, 2015;10(6):e0129547.
PMID: 26057251 DOI: 10.1371/journal.pone.0129547

Antibiotic resistance genes and antibiotics are frequently used to maintain plasmid vectors in bacterial hosts such as Escherichia coli. Due to the risk of spread of antibiotic resistance, the regulatory authorities discourage the use of antibiotic resistance genes/antibiotics for the maintenance of plasmid vectors in certain biotechnology applications. Overexpression of E. coli endogenous fabI gene and subsequent selection on Triclosan has been proposed as a practical alternative to traditional antibiotic selection systems. Unfortunately, overexpression of fabI cannot be used to select medium-copy number plasmids, typically used for the expression of heterologous proteins in E. coli. Here we report that Vibrio cholera FabV, a functional homologue of E. coli FabI, can be used as a suitable marker for the selection and maintenance of both high and medium-copy number plasmid vectors in E. coli.
Report: Antibacterial activity of a peptide derived from HIV-1 MN strain gp41 envelope glycoprotein against methicillin-resistant Staphylococcus aureus

Teow SY, Ali SA

Pak J Pharm Sci, 2016 Nov;29(6):2119-2124.
PMID: 28375134

Peptides derived from HIV-1 transmembrane proteins have been extensively studied for antimicrobial activities, and they are known as antimicrobial peptides (AMPs). These AMPs have also been reported to potently combat the drug-resistant microbes. In this study, we demonstrated that peptide #6383 originated from HIV-1 MN strain membrane-spanning domain of gp41 was active (2-log reductions) at 100βg/mL (56.5βM) against methicillin-resistant Staphylococcus aureus (MRSA) in 10% and 50% human plasma-supplemented phosphate buffered saline (PBS). The activity was further enhanced (3-log reductions) in the presence of 5% human serum albumin (HSA) alone. All bactericidal activities were achieved within 6 hours. At 100μg/mL, the peptide showed only 13% toxicity against human erythrocytes. This peptide can serve as an attractive template for a design of a novel peptide antibiotic against drug-resistant bacteria. By sequence-specific engineering or modifications, we anticipated that the bactericidal activity and the reduced toxicity against human erythrocytes will be improved.
Impact of bovine and human serum albumin on Curcumin in vitro activity against Staphylococcus aureus

Teow SY, Ali SA

Pak J Pharm Sci, 2017 May;30(3):891-895.
PMID: 28653935

This study evaluated the impact of pH (7.4 and 6.5), bovine serum albumin (BSA), and human serum albumin (HSA) on Curcumin activity against 2 reference, 1 clinical, and 10 environmental strains of Staphylococcus aureus (S. aureus). Minimal inhibitory concentrations (MICs) of Curcumin against S. aureus were statistically indifferent (p>0.05) at pH7.4 and pH6.5. Activity of Curcumin against S. aureus was reduced by two folds in the presence of 1.25-5% BSA/HSA.
Fulltext Synergistic antibacterial activity of Curcumin with antibiotics against Staphylococcus aureus

Teow SY, Ali SA

Pak J Pharm Sci, 2015 Nov;28(6):2109-14.
PMID: 26639480

This study evaluated the synergistic antibacterial activity of Curcumin with 8 different antibiotic groups. Two reference, one clinical and ten environmental strains of Staphylococcus aureus (S. aureus) were tested. Disc diffusion assay with 25 μg/mL Curcumin demonstrated synergism in combination with a majority of tested antibiotics against S. aureus. However, checkerboard micro dilution assay only showed synergism, fractional inhibitory concentration index (FICI) <0.5 in three antibiotics i.e. Gentamicin, Amikacin, and Ciprofloxacin. Other antibiotics showed indifferent interactions but no antagonism was observed. In time-kill curve, appreciable reduction of bacterial cells was also observed in combination therapy (Curcumin + antibiotics) compared to monotherapy (Curcumin or antibiotic(s) alone). The antibiotics with higher synergistic interaction with Curcumin are arranged in a decreasing order: Amikacin > Gentamicin > Ciprofloxacin.
Altered antibacterial activity of Curcumin in the presence of serum albumin, plasma and whole blood

Teow SY, Ali SA

Pak J Pharm Sci, 2017 Mar;30(2):449-457.
PMID: 28649069

Antibacterial effect is one of the major therapeutic activities of plant-derived Curcumin. This work evaluated the effect of serum albumin, human plasma, and whole blood on the in vitro activity of Curcumin against eight clinical bacterial isolates by standard broth microdilution and plate-counting methods. Toxicological effects of Curcumin towards human red blood cells (RBCs) and peripheral blood mononuclear cells (PBMCs) were also investigated. Curcumin exhibited weak activity against gram-negative bacteria, except Escherichia coli and Shigella flexneri were susceptible and was most active against gram-positive bacteria: Staphylococcus aureus, Streptococcus pyogenes and Enterococcus faecalis. The antibacterial activity was impaired in the presence of bovine serum albumin (BSA), human plasma and whole blood. Curcumin was not toxic to PBMCs and RBCs at 200μg/mL. Furthermore, Curcumin showed synergistic activity in combination with antibiotics: Ciprofloxacin, Gentamicin, Vancomycin and Amikacin against Staphylococcus aureus. This study demonstrated that the interaction of Curcumin with plasma proteins diminishes its in vitro antibacterial activity. Curcumin derivatives with reduced affinity for plasma protein may improve the bioavailability and antibacterial activities.
Fulltext Use of FabV-Triclosan Plasmid Selection System for Efficient Expression and Production of Recombinant Proteins in Escherichia coli

Ali SA, Chew YW, Omar TC, Azman N

PLoS One, 2015;10(12):e0144189.
PMID: 26642325 DOI: 10.1371/journal.pone.0144189

Maintenance of recombinant plasmid vectors in host bacteria relies on the presence of selection antibiotics in the growth media to suppress plasmid -free segregants. However, presence of antibiotic resistance genes and antibiotics themselves is not acceptable in several applications of biotechnology. Previously, we have shown that FabV-Triclosan selection system can be used to select high and medium copy number plasmid vectors in E. coli. Here, we have extended our previous work and demonstrated that expression vectors containing FabV can be used efficiently to express heterologous recombinant proteins in similar or better amounts in E. coli host when compared with expression vectors containing β-lactamase. Use of small amount of non-antibiotic Triclosan as selection agent in growth medium, enhanced plasmid stability, applicability in various culture media, and compatibility with other selection systems for multiple plasmid maintenance are noteworthy features of FabV-Triclosan selection system.
Fulltext Exosomes in Human Immunodeficiency Virus Type I Pathogenesis: Threat or Opportunity?

Teow SY, Nordin AC, Ali SA, Khoo AS

Adv Virol, 2016;2016:9852494.
PMID: 26981123 DOI: 10.1155/2016/9852494

Nanometre-sized vesicles, also known as exosomes, are derived from endosomes of diverse cell types and present in multiple biological fluids. Depending on their cellular origins, the membrane-bound exosomes packed a variety of functional proteins and RNA species. These microvesicles are secreted into the extracellular space to facilitate intercellular communication. Collective findings demonstrated that exosomes from HIV-infected subjects share many commonalities with Human Immunodeficiency Virus Type I (HIV-1) particles in terms of proteomics and lipid profiles. These observations postulated that HIV-resembled exosomes may contribute to HIV pathogenesis. Interestingly, recent reports illustrated that exosomes from body fluids could inhibit HIV infection, which then bring up a new paradigm for HIV/AIDS therapy. Accumulative findings suggested that the cellular origin of exosomes may define their effects towards HIV-1. This review summarizes the two distinctive roles of exosomes in regulating HIV pathogenesis. We also highlighted several additional factors that govern the exosomal functions. Deeper understanding on how exosomes promote or abate HIV infection can significantly contribute to the development of new and potent antiviral therapeutic strategy and vaccine designs.
Intestinal parasitic infections frequency in referred patients to a large teaching hospital, Khuzestan, Southwest, Iran, 2017

Feiz Haddad MH, Maraghi S, Ali SA, Feiz Haddad R, Nasser Zadeh R

Trop Biomed, 2018 Dec 01;35(4):915-925.
PMID: 33601841

Intestinal parasitic infections (IPIs) are among the most important infectious diseases in Iran. A cross sectional study was designed to determine frequency of intestinal parasites among referrals to a large teaching hospital in Khuzestan, Southwest of Iran, 2017. A total number of 5613 stool samples were examined through direct smear and formalin-ether concentration methods to detect possible parasitic infections. Samples consisted of 2643 (47.09%) male and 2970 (52.91%) female. A total of 1468 (26.15%) samples were positive (13.11% male and 13.4% female) and 4145 (73.85%) were negative. The results also showed that 255 of samples had more than one type of parasite (mix infections). Counting single and mix parasite infections, the total number of positive cases reached to 1723. Helminthes parasites were present in 12 (0.7%) cases, while intestinal protozoan parasites were in 1711 (99.3%) cases. Almost equally, pathogenic and nonpathogenic parasites infected 860 (49.91%) and 863 (50.09%) of patients, respectively. The frequency for helminthes was determined at 0.52% with Hymenolepis nana and Enterobius vermicularis however, Giardia lamblia in 38.54% and Entamoeba histolytica/dispar at 10.68% were concluded as protozoa elements. The IPIs frequency was recorded in female and male patients at 49.16% and 50.14%, respectively. According to the current results the infection rate of intestinal parasites has been significantly reduced especially for helminths infections in this region possibly due to public attention to health issues such as; increased awareness of people, improvement of sanitation, seasonal variations, health education and personal hygiene.
WITHDRAWN: Patient-specific interface pressure case study at transradial prosthetic socket: comparison trials between ICRC polypropylene socket and air splint socket

Abd Razak NA, Abu Osman NA, Ali SA, Gholizadeh H

Eur J Phys Rehabil Med, 2016 Jan 15.
PMID: 26771916

Ahead of Print article withdrawn by publisher
Fulltext Genetic Modifications of Developmental Dyslexia and Its Representation Using In Vivo, In Vitro Model

Zaki ZMM, Ali SA, Ghazali MM, Jam FA

Glob Med Genet, 2024 Jan;11(1):76-85.
PMID: 38414980 DOI: 10.1055/s-0044-1781456

Dyslexia is a genetic and heritable disorder that has yet to discover the treatment of it, especially at the molecular and drug intervention levels. This review provides an overview of the current findings on the environmental and genetic factors involved in developmental dyslexia. The latest techniques used in diagnosing the disease and macromolecular factors findings may contribute to a higher degree of development in detangling the proper management and treatment for dyslexic individuals. Furthermore, this review tried to put together all the models used in the current dyslexia research for references in future studies that include animal models as well as in vitro models and how the previous research has provided consistent data across many years and regions. Thus, we suggest furthering the studies using an organoid model based on the existing gene polymorphism, pathways, and neuronal function input.
The Presentation of Older People with Vertebral Fragility Fractures to a University Hospital: A Cross-sectional Analysis

Ong T, Bin Syed Ali SA, Sahota O

Curr Rheumatol Rev, 2021;17(1):109-112.
PMID: 32867654 DOI: 10.2174/1573397116999200820170559

INTRODUCTION: There is a lack of robust data on hospitalised acute vertebral fragility fractures. This analysis aimed to report on the number of hospitalised vertebral fragility fractures treated in a large UK teaching hospital. This information would support better design of hospital services and resource allocation to manage this group of patients.
METHODS: Patients aged 50 years and over hospitalised with a vertebral fragility fracture from 1/2/2016 to 31/1/2017 were identified from radiology and hospital records. Patients sustaining vertebral fractures due to either major trauma or malignancy were excluded. Data was collected on patient demographics, fracture details, hospitalisation details and health outcomes.
RESULTS: 208 patients with acute vertebral fragility fractures were hospitalised over a 12 month period. The mean (SD) age was 80.5 (11) years, of which 68% were female. 94% presented to the Emergency Department (ED) as their first point of contact, of which 70% were subsequently hospitalised. Two-thirds presented with a single level vertebral fracture predominantly around the thoracolumbar region. The majority (87%) were non-operatively managed by general physicians, of which most were under Geriatric Medicine. The median length of stay was 12 (IQR 6-20) days and inpatient mortality was 3%. 52% of patients went on to have a bone health assessment.
CONCLUSION: We have reported on the number of patients presenting to hospital with an acute vertebral fragility fracture over 12 months. This helps identify resources needed to design hospital services to manage them adequately.
Nodular Melanoma Mimicking Keratoacanthoma: Lessons to learn

Muthupalaniappen L, Das S, Md Nor N, Ali SA

Sultan Qaboos Univ Med J, 2012 Aug;12(3):360-3.
PMID: 22912931

A 67-year-old man of Chinese descent presented with a painless nodular lesion that had been present on his right forearm for the previous 3 months. A single, well-defined, dome-shaped, firm nodule with a central keratin plug surrounded by erythema was noted. Keratoacanthoma with secondary bacterial infection was suspected and the patient underwent an excision biopsy. Biopsy of the nodule and immunohistochemical staining supported a diagnosis of nodular malignant melanoma. It should be noted both that nodular malignant melanoma may present with a wide variety of clinical appearances, and that the lack of melanin pigment in nodular malignant melanoma may hinder the diagnosis of this aggressive tumour.
Fulltext A Cell Internalizing Antibody Targeting Capsid Protein (p24) Inhibits the Replication of HIV-1 in T Cells Lines and PBMCs: A Proof of Concept Study

Ali SA, Teow SY, Omar TC, Khoo AS, Choon TS, Yusoff NM

PLoS One, 2016;11(1):e0145986.
PMID: 26741963 DOI: 10.1371/journal.pone.0145986

There remains a need for newer therapeutic approaches to combat HIV/AIDS. Viral capsid protein p24 plays important roles in HIV pathogenesis. Peptides and small molecule inhibitors targeting p24 have shown to inhibit virus replication in treated cell. High specificity and biological stability of monoclonal antibodies (mAbs) make them an attractive contender for in vivo treatments. However, mAbs do not enter into cells, thus are restricted to target surface molecules. This also makes targeting intracellular HIV-1 p24 a challenge. A mAb specific to p24 that can internalize into the HIV-infected cells is hypothesized to inhibit the virus replication. We selected a mAb that has previously shown to inhibit p24 polymerization in an in vitro assay and chemically conjugated it with cell penetrating peptides (CPP) to generate cell internalizing anti-p24 mAbs. Out of 8 CPPs tested, κFGF-MTS -conjugated mAbs internalized T cells most efficiently. At nontoxic concentration, the κFGF-MTS-anti-p24-mAbs reduced the HIV-1 replication up to 73 and 49% in T-lymphocyte and PBMCs respectively. Marked inhibition of HIV-1 replication in relevant cells by κFGF-MTS-anti-p24-mAbs represents a viable strategy to target HIV proteins present inside the cells.
Fulltext A comparative study of non-viral gene delivery techniques to human adipose-derived mesenchymal stem cell

Abdul Halim NS, Fakiruddin KS, Ali SA, Yahaya BH

Int J Mol Sci, 2014;15(9):15044-60.
PMID: 25162825 DOI: 10.3390/ijms150915044

Mesenchymal stem cells (MSCs) hold tremendous potential for therapeutic use in stem cell-based gene therapy. Ex vivo genetic modification of MSCs with beneficial genes of interest is a prerequisite for successful use of stem cell-based therapeutic applications. However, genetic manipulation of MSCs is challenging because they are resistant to commonly used methods to introduce exogenous DNA or RNA. Herein we compared the effectiveness of several techniques (classic calcium phosphate precipitation, cationic polymer, and standard electroporation) with that of microporation technology to introduce the plasmid encoding for angiopoietin-1 (ANGPT-1) and enhanced green fluorescent protein (eGFP) into human adipose-derived MSCs (hAD-MSCs). The microporation technique had a higher transfection efficiency, with up to 50% of the viable hAD-MSCs being transfected, compared to the other transfection techniques, for which less than 1% of cells were positive for eGFP expression following transfection. The capability of cells to proliferate and differentiate into three major lineages (chondrocytes, adipocytes, and osteocytes) was found to be independent of the technique used for transfection. These results show that the microporation technique is superior to the others in terms of its ability to transfect hAD-MSCs without affecting their proliferation and differentiation capabilities. Therefore, this study provides a foundation for the selection of techniques when using ex vivo gene manipulation for cell-based gene therapy with MSCs as the vehicle for gene delivery.
Fulltext Dengue virus type 2 (DENV2)-induced oxidative responses in monocytes from glucose-6-phosphate dehydrogenase (G6PD)-deficient and G6PD normal subjects

Al-Alimi AA, Ali SA, Al-Hassan FM, Idris FM, Teow SY, Mohd Yusoff N

PLoS Negl Trop Dis, 2014 Mar;8(3):e2711.
PMID: 24625456 DOI: 10.1371/journal.pntd.0002711

Dengue virus is endemic in peninsular Malaysia. The clinical manifestations vary depending on the incubation period of the virus as well as the immunity of the patients. Glucose-6-phosphate dehydrogenase (G6PD) deficiency is prevalent in Malaysia where the incidence is 3.2%. It has been noted that some G6PD-deficient individuals suffer from more severe clinical presentation of dengue infection. In this study, we aim to investigate the oxidative responses of DENV2-infected monocytes from G6PD-deficient individuals.
Gelsolin and ceruloplasmin as potential predictive biomarkers for cervical cancer by 2D-DIGE proteomics analysis

Lokamani I, Looi ML, Md Ali SA, Mohd Dali AZ, Ahmad Annuar MA, Jamal R

Pathol Oncol Res, 2014 Jan;20(1):119-29.
PMID: 23925487 DOI: 10.1007/s12253-013-9670-9

This study aimed to identify candidate proteins which may serve as potential biological markers for cervical cancer using 2D-DIGE. Serum samples of controls, patients with cervical intraepithelial neoplasia grade 3 (CIN 3), squamous cell carcinoma of early (SCC I and II) and late (SCC III and IV) stage were subjected to 2D-DIGE. Differentially expressed spots were identified by tandem mass spectrometry. Validation of candidate proteins in serum and tissue samples were then performed by ELISA and immunohistochemistry (IHC) analysis respectively. A total of 20 differentially expressed proteins were identified. These proteins were found to play key roles in the apoptosis pathway, complement system, various types of transportation such as hormones, fatty acids, lipid, vitamin E and drug transportation, coagulation cascade, regulation of iron and immunologic response. Based on their functional relevancy to the progression of various cancers, 4 proteins namely the complement factor H, CD5-like antigen, gelsolin and ceruloplasmin were chosen for further validation using ELISA. Biological network analysis showed that ceruloplasmin and gelsolin are closely interacted with the oncogene NF-κb. These two proteins were further validated using the IHC. Gelsolin and ceruloplasmin may serve as potential predictive biomarkers for the progression of high grade lesions.
Clusterin as a potential marker in distinguishing cervical neoplasia

Lokamani I, Looi ML, Ali SA, Dali AZ, Jamal R

Anal. Quant. Cytol. Histol., 2011 Aug;33(4):223-8.
PMID: 21980627

To assess the immunoexpression of clusterin (CLU) in the progression of cervical neoplasia.
Fulltext Spontaneous bladder perforation: a rare complication of tuberculosis

Kong CH, Ali SA, Singam P, Hong GE, Cheok LB, Zainuddin ZM

Int J Infect Dis, 2010 Sep;14 Suppl 3:e250-2.
PMID: 20117032 DOI: 10.1016/j.ijid.2009.10.006

Spontaneous bladder perforation secondary to tuberculosis (TB) is very rare. Only three cases have been reported so far in the literature. Due to its rarity, the diagnosis of spontaneous bladder perforation is often missed. Confirmation of TB via culture takes a long time and starting empirical treatment for TB is necessary. We relate our experience with a young woman who presented with clinical features of a perforated appendix and was only diagnosed with bladder perforation during laparotomy. She also had distal right ureteral stricture and left infundibular stenosis. The provisional diagnosis of TB was attained via typical histopathological features and a positive Mantoux test. She was started empirically on anti-TB treatment and recovered without any complications. Urine culture after 6 weeks confirmed the diagnosis of TB.
A mouse IgM monoclonal antibody recognizes breast and colon cancer

Bakar AF, Alitheen NB, Keong YS, Hamid M, Ali SA, Ali AM

Hybridoma (Larchmt), 2009 Jun;28(3):199-203.
PMID: 19519247 DOI: 10.1089/hyb.2007.0531

Hybridoma clone C3A8, which is a fusion product between splenic lymphocytes of Balb/c mice immunized with MCF7 breast carcinoma cells and SP2/0 myelomas, was produced and characterized. A stable clone that secreted IgM monoclonal antibody (MAb) with kappa light chain was obtained through limiting dilutions. Cell-ELISA screening, flow cytometry analysis, and immunofluorescence staining revealed that the MAb C3A8 had bound specifically and strongly to MCF7 and HT29 but cross reacted weakly or not on HeLa cell line. The MAb C3A8 reacted positively with paraffin-embedded tissues of human breast and colon cancers but there were no positive reactions on normal tissues. Western blot analysis showed the MAb recognized a 55 kDa protein, which was present in the extract of MCF7 and HT29 cell lines. Our results demonstrated that MAb C3A8 could be used for basic and clinical research of breast and colon cancers.
Construction and characterization of rtxA and rtxC mutants of auxotrophic O139 Vibrio cholerae

Cheong TG, Chan M, Kurunathan S, Ali SA, ZiNing T, Zainuddin ZF, et al.

Microb Pathog, 2010 Feb;48(2):85-90.
PMID: 19900531 DOI: 10.1016/j.micpath.2009.11.001

Vibrio cholerae is a Gram-negative bacterium that causes diarrheal disease. V. cholerae O1 and O139 serogroups are toxigenic and are known to cause epidemic cholera. These serogroups produce cholera toxin and other accessory toxins such as accessory cholera enterotoxin, zonula occludens toxin, and multifunctional, autoprocessing repeat in toxin (MARTX). In the present study, we incorporated mutated rtxA and rtxC genes that encode MARTX toxin into the existing aminolevulinic acid (ALA) auxotrophic vaccine candidate VCUSM2 of V. cholerae O139 serogroup. The rtxC mutant was named VCUSM9 and the rtxC/rtxA mutant was named VCUSM10. VCUSM9 and VCUSM10 were able to colonize intestinal cells well, compared with the parent vaccine strain, and produced no fluid accumulation in a rabbit ileal loop model. Cell rounding and western blotting assays indicated that mutation of the rtxC gene alone (VCUSM9 strain) did not abolish MARTX toxicity. However mutation of both the rtxA and rtxC genes (VCUSM10) completely abolished MARTX toxicity. Thus we have produced a new, less reactogenic, auxotrophic rtxC/rtxA mutated vaccine candidate against O139 V. cholerae.

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