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Recent developments on (-)-colchicine derivatives: Synthesis and structure-activity relationship

Ghawanmeh AA, Al-Bajalan HM, Mackeen MM, Alali FQ, Chong KF

Eur J Med Chem, 2020 Jan 01;185:111788.
PMID: 31655432 DOI: 10.1016/j.ejmech.2019.111788

(-)-Colchicine, an anti-microtubulin polymerization agent, is a valuable medication and the drug of choice for gout, Behçet's disease and familial Mediterranean fever. It has a narrow therapeutic index due to its high toxicity towards normal cells. Nonetheless, numerous (-)-colchicine derivatives have been synthesized and studied for their structure-activity relationship and preferential toxicity. Different functional groups such as amides, thioamides, N-arylurea and 8,12-diene cyclic have been incorporated into (-)-colchicine, resulting in derivatives (with moieties) that include electron-withdrawing and electron-donating groups. This review article focuses on recent developments in the chemical synthesis of (-)-colchicine derivatives, the substituents used, the functional groups linked to the substituents, the moieties and biological studies. Moreover, the current classification of derivatives based on the (-)-colchicine rings, namely ring A, B, and C (-)-colchicine derivatives, is discussed. This work demonstrates and summarizes the significance of (-)-colchicine derivatives in the biological field, and discusses their promising therapeutics for the future.
Fulltext Purification and kinetics of the PHB depolymerase of Microbacterium paraoxydans RZS6 isolated from a dumping yard

Sayyed RZ, Wani SJ, Alyousef AA, Alqasim A, Syed A, El-Enshasy HA

PLoS One, 2019;14(6):e0212324.
PMID: 31211775 DOI: 10.1371/journal.pone.0212324

Poly-β-hydroxybutyrate (PHB) depolymerase is known to decompose PHB, biodegradable polymers and therefore has great commercial significance in the bioplastic sector. However, reports on PHB depolymerases from isolates obtained from plastic-contaminated sites that reflect the potential of the source organism is scarce. In this study, we evaluated the production of extracellular PHB depolymerase from Microbacterium paraoxydans RZS6 isolated from the plastic-contaminated site in the municipal area of Shahada, Maharashtra, India, for the first time. The isolate was identified using 16S rRNA gene sequencing, gas chromatographic analysis of fatty acid methyl esters (GC-FAME), and BIOLOG method. Ithydrolyzed PHB on minimal salt medium (MSM) containing PHB as the only source of carbon. The isolate produced PHB depolymerase at 45°C during 48 h of incubation. The enzyme was purified most efficiently using octyl-sepharose CL-4B column, with the highest purification yield of 6.675 Umg-1mL-1. The activity of the enzyme was enhanced in the presence of Ca2+ and Mg2+ ions but inhibited by Fe2+ (1 mM) ions and mercaptoethanol (1000 rpm). the nzyme kinetic analysis revealed that the enzyme was a metalloenzyme; requiring Mg2+ ions, that showed optimum enzyme activity at 30°C (mesophilic) and under neutrophilic (pH 7) conditions. Scale-up from the shake-flask level to a laboratory-scale bioreactor further enhanced the enzyme yield by 0.809 UmL-1. The molecular weight of the enzyme (40 kDa), as estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, closely resembled the PHB depolymerase of Aureobacterium saperdae. Our findings highlighted the applicability of M. paraoxydans as a producer of extracellular PHB depolymerase having potential of degrading PHB under diverse conditions.
Fulltext Multifunctional applications of natural polysaccharide starch and cellulose: An update on recent advances

Gopinath V, Kamath SM, Priyadarshini S, Chik Z, Alarfaj AA, Hirad AH

Biomed Pharmacother, 2022 Feb;146:112492.
PMID: 34906768 DOI: 10.1016/j.biopha.2021.112492

The emergence of clinical complications and therapeutic challenges for treating various diseases necessitate the discovery of novel restorative functional materials. Polymer-based drug delivery systems have been extensively reported in the last two decades. Recently, there has been an increasing interest in the progression of natural biopolymers based controlled therapeutic strategies, especially in drug delivery and tissue engineering applications. However, the solubility and functionalisation due to their complex network structure and intramolecular bonding seem challenging. This review explores the current advancement and prospects of the most promising natural polymers such as cellulose, starch and their derivatives-based drug delivery vehicles like hydrogels, films and composites, in combating major ailments such as bone infections, microbial infections, and cancers. In addition, selective drug targeting using metal-drug (MD) and MD-based polymeric missiles have been exciting but challenging for its application in cancer therapeutics. Owing to high biocompatibility of starch and cellulose, these materials have been extensively evaluated in biomedical and pharmaceutical applications. This review presents a detailed impression of the current trends for the construction of biopolymer-based tissue engineering, drug/gene/protein delivery vehicles.
The synthesis, characterization and in vivo study of mineral substituted hydroxyapatite for prospective bone tissue rejuvenation applications

Govindaraj D, Rajan M, Munusamy MA, Alarfaj AA, Sadasivuni KK, Kumar SS

Nanomedicine, 2017 Nov;13(8):2661-2669.
PMID: 28800874 DOI: 10.1016/j.nano.2017.07.017

Minerals substituted apatite (M-HA) nanoparticles were prepared by the precipitation of minerals and phosphate reactants in choline chloride-Thiourea (ChCl-TU) deep eutectic solvent (DESs) as a facile and green way approach. After preparation of nanoparticles (F-M-HA (F=Fresh solvent)), the DESs was recovered productively and reprocess for the preparation of R-M-HA nanoparticles (R=Recycle solvent).The functional groups, phase, surface texture and the elemental composition of the M-HA nanoparticles were evaluated by advance characterization methods. The physicochemical results of the current work authoritative the successful uses of the novel (ChCl-TU) DESs as eco-friendly recuperate and give the medium for the preparation of M-HA nanoparticles. Moreover, the as-synthesized both M-HA nanoparticles exhibit excellent biocompatibility, consisting of cell co-cultivation and cell adhesion, in vivo according to surgical implantation of Wistar rats.
Fulltext Educational Module Intervention for Radiographers to Reduce Repetition Rate of Routine Digital Chest Radiography in Makkah Region of Saudi Arabia Tertiary Hospitals: Protocol of a Quasi-Experimental Study

Almalki AA, Abdul Manaf R, Hanafiah Juni M, Kadir Shahar H, Noor NM, Gabbad A

JMIR Res Protoc, 2017 Sep 26;6(9):e185.
PMID: 28951379 DOI: 10.2196/resprot.8007

BACKGROUND: Repetition of an image is a critical event in any radiology department. When the repetition rate of routine digital chest radiographs is high, radiation exposure of staff and patients is increased. In addition, repetition consumes the equipment's life span, thus affecting the annual budget of the department.
OBJECTIVE: The aim of this study is to determine the impact of a printed educational module on reducing the repetition rate of routine digital chest radiography among radiographers in Makkah Region tertiary hospitals.
METHODS: A quasi-experimental time series with a control group will be conducted in Makkah Region tertiary hospitals for 8 months starting in the second quarter of 2017. Four hospitals out of 5 in the region will be selected; 2 of them will be selected as the control group and the other 2 as the intervention group. Stratification and a simple random sampling technique will be used to sample 56 radiographers in each group. Pre- and postintervention assessments will be conducted to determine the radiographer knowledge, motivation, and skills and repetition rate of chest radiographs. Radiographs of the chest performed by sampled radiographers in the selected hospitals will be collected for 2 weeks before and after the intervention. A piloted questionnaire will be distributed and collected by a researcher in both groups. One-way multivariate analysis of variance and 2-way repeated multivariate analysis of variance will be used to analyze the data.
RESULTS: It is expected that the repetition rate in the intervention group will decline after implementing the intervention and the change will be statistically significant (P
Stem Cell Therapies for Reversing Vision Loss

Higuchi A, Kumar SS, Benelli G, Alarfaj AA, Munusamy MA, Umezawa A, et al.

Trends Biotechnol, 2017 11;35(11):1102-1117.
PMID: 28751147 DOI: 10.1016/j.tibtech.2017.06.016

Current clinical trials that evaluate human pluripotent stem cell (hPSC)-based therapies predominantly target treating macular degeneration of the eyes because the eye is an isolated tissue that is naturally weakly immunogenic. Here, we discuss current bioengineering approaches and biomaterial usage in combination with stem cell therapy for macular degeneration disease treatment. Retinal pigment epithelium (RPE) differentiated from hPSCs is typically used in most clinical trials for treating patients, whereas bone marrow mononuclear cells (BMNCs) or mesenchymal stem cells (MSCs) are intravitreally transplanted, undifferentiated, into patient eyes. We also discuss reported negative effects of stem cell therapy, such as patients becoming blind following transplantation of adipose-derived stem cells, which are increasingly used by 'stem-cell clinics'.
Colchicine prodrugs and codrugs: Chemistry and bioactivities

Ghawanmeh AA, Chong KF, Sarkar SM, Bakar MA, Othaman R, Khalid RM

Eur J Med Chem, 2018 Jan 20;144:229-242.
PMID: 29274490 DOI: 10.1016/j.ejmech.2017.12.029

Antimitotic colchicine possesses low therapeutic index due to high toxicity effects in non-target cell. However, diverse colchicine analogs have been derivatized as intentions for toxicity reduction and structure-activity relationship (SAR) studying. Hybrid system of colchicine structure with nontoxic biofunctional compounds modified further affords a new entity in chemical structure with enhanced activity and selectivity. Moreover, nanocarrier formulation strategies have been used for colchicine delivery. This review paper focuses on colchicine nanoformulation, chemical synthesis of colchicine prodrugs and codrugs with different linkers, highlights linker chemical nature and biological activity of synthesized compounds. Additionally, classification of colchicine prodrugs based on type of conjugates is discussed, as biopolymers prodrugs, fluorescent prodrug, metal complexes prodrug, metal-labile prodrug and bioconjugate prodrug. Finally, we briefly summarized the biological importance of colchicine nanoformulation, colchicine prodrugs and codrugs.
Fulltext Production, purification and evaluation of biodegradation potential of PHB depolymerase of Stenotrophomonas sp. RZS7

Sayyed RZ, Wani SJ, Alarfaj AA, Syed A, El-Enshasy HA

PLoS One, 2020;15(1):e0220095.
PMID: 31910206 DOI: 10.1371/journal.pone.0220095

There are numerous reports on poly-β-hydroxybutyrate (PHB) depolymerases produced by various microorganisms isolated from various habitats, however, reports on PHB depolymerase production by an isolate from plastic rich sites scares. Although PHB has attracted commercial significance, the inefficient production and recovery methods, inefficient purification of PHB depolymerase and lack of ample knowledge on PHB degradation by PHB depolymerase have hampered its large scale commercialization. Therefore, to ensure the biodegradability of biopolymers, it becomes imperative to study the purification of the biodegrading enzyme system. We report the production, purification, and characterization of extracellular PHB depolymerase from Stenotrophomonas sp. RZS7 isolated from a dumping yard rich in plastic waste. The isolate produced extracellular PHB depolymerase in the mineral salt medium (MSM) at 30°C during 4 days of incubation under shaking. The enzyme was purified by three methods namely ammonium salt precipitation, column chromatography, and solvent purification. Among these purification methods, the enzyme was best purified by column chromatography on the Octyl-Sepharose CL-4B column giving optimum yield (0.7993 Umg-1mL-1). The molecular weight of purified PHB depolymerase was 40 kDa. Studies on the assessment of biodegradation of PHB in liquid culture medium and under natural soil conditions confirmed PHB biodegradation potential of Stenotrophomonas sp. RZS7. The results obtained in Fourier-Transform Infrared (FTIR) analysis, High-Performance Liquid Chromatography (HPLC) study and Gas Chromatography Mass-Spectrometry (GC-MS) analysis confirmed the biodegradation of PHB in liquid medium by Stenotrophomonas sp. RZS7. Changes in surface morphology of PHB film in soil burial as observed in Field Emission Scanning Electron Microscopy (FESEM) analysis confirmed the biodegradation of PHB under natural soil environment. The isolate was capable of degrading PHB and it resulted in 87.74% biodegradation. A higher rate of degradation under the natural soil condition is the result of the activity of soil microbes that complemented the biodegradation of PHB by Stenotrophomonas sp. RZS7.
Screening of ionic liquids as green entrainers for ethanol water separation by extractive distillation: COSMO-RS prediction and aspen plus simulation

Malik H, Khan HW, Hassan Shah MU, Ahmad MI, Khan I, Al-Kahtani AA, et al.

Chemosphere, 2023 Jan;311(Pt 2):136901.
PMID: 36288769 DOI: 10.1016/j.chemosphere.2022.136901

Ionic liquids (ILs) have been demonstrated as promising alternatives to conventional entrainers in separation of azeotropic mixtures mostly investigating phase equilibrium and process design scenarios. However, proper selection of ILs for a specific task always remains challenging. Hence a simulation tool, i.e. conductor like screening model for real solvents (COSMO-RS) was applied to address this challenge. Furthermore, screened ILs were simulated as entrainers for ethanol water separation by extractive distillation. The current study also aims to demonstrate a systematic approach to retrofit existing processes, by employing ILs as green entrainers. Screening of twenty-five (25) ILs was carried out using COSMO-RS to select suitable ILs as green entrainers based on activity coefficient, capacity and selectivity. Results illustrated that tetramethylammonium chloride ([TMAm][Cl]) due to its strong hydrogen bonding ability was found to be the best ILs entrainer. Moreover, in order to reduce the operating costs without compromising desired product purity (ethanol purity ≥99.5% in top product), the selected ILs (8 kg/h) in a mixture with ethylene glycol (72 kg/h) were simulated using Aspen plus v.11. The simulation results revealed that by combining tetramethylammonium chloride (2 kg/h) with ethylene glycol (78 kg/h) reduced 7.26 tons of CO2 emissions/year through heat integration by saving 1.49*108 kJ/year energy besides minimizing operating costs. In conclusion, the systematic selection of ILs as green entrainers in combination with ethylene glycol and then the appropriate simulation of the whole system will ultimately reduce the cost of the separation process and reduce the emission of greenhouse gases as well utilization of toxic conventional entrainers.
Synthesis and characterization of 4-nitro benzaldehyde with ZnO-based nanoparticles for biomedical applications

Indumathi T, Kumaresan I, Suriyaprakash J, Alarfaj AA, Hirad AH, Jaganathan R, et al.

J Basic Microbiol, 2024 Feb;64(2):e2300494.
PMID: 37988661 DOI: 10.1002/jobm.202300494

Globally, cancer is the leading cause of death and morbidity, and skin cancer is the most common cancer diagnosis. Skin problems can be treated with nanoparticles (NPs), particularly with zinc oxide (ZnO) NPs, which have antioxidant, antibacterial, anti-inflammatory, and anticancer properties. An antibacterial activity of zinc oxide nanoparticles prepared in the presence of 4-nitrobenzaldehyde (4NB) was also tested in the present study. In addition, the influence of synthesized NPs on cell apoptosis, cell viability, mitochondrial membrane potential (MMP), endogenous reactive oxygen species (ROS) production, apoptosis, and cell adhesion was also examined. The synthesized 4-nitro benzaldehyde with ZnO (4NBZnO) NPs were confirmed via characterization techniques. 4NBZnO NPs showed superior antibacterial properties against the pathogens tested in antibacterial investigations. As a result of dose-based treatment with 4NBZnO NPs, cell viability, and MMP activity of melanoma cells (SK-MEL-3) cells were suppressed. A dose-dependent accumulation of ROS was observed in cells exposed to 4NBZnO NPs. As a result of exposure to 4NBZnO NPs in a dose-dependent manner, viable cells declined and apoptotic cells increased. This indicates that apoptotic cell death was higher. The cell adhesion test revealed that 4NBZnO NPs reduced cell adhesion and may promote apoptosis of cancer cells because of enhanced ROS levels.
Synergistic effects of CuO/TiO2 -chitosan-farnesol nanocomposites: Synthesis, characterization, antimicrobial, and anticancer activities on melanoma cells SK-MEL-3

Indumathi T, Suriyaprakash J, Alarfaj AA, Hirad AH, Jaganathan R, Mathanmohun M

J Basic Microbiol, 2024 Feb;64(2):e2300505.
PMID: 37988658 DOI: 10.1002/jobm.202300505

The current investigation focuses on synthesizing copper oxide (CuO)-titanium oxide (TiO2 )-chitosan-farnesol nanocomposites with potential antibacterial, antifungal, and anticancer properties against Melanoma cells (melanoma cells [SK-MEL-3]). The nanocomposites were synthesized using the standard acetic acid method and subsequently characterized using an X-ray diffractometer, scanning electron microscope, transmission electron microscopy, and Fourier transform infrared spectroscopy. The results from the antibacterial tests against Streptococcus pneumoniae and Stapylococcus aureus demonstrated significant antibacterial efficacy. Additionally, the antifungal studies using Candida albicans through the agar diffusion method displayed a considerable antifungal effect. For evaluating the anticancer activity, various assays such as MTT assay, acridine orange/ethidium bromide dual staining assay, reactive oxygen species (ROS) generation assay, and mitochondrial membrane potential (MMP) analysis were conducted on SK-MEL-3 cells. The nanocomposites exhibited the ability to induce ROS generation, decrease MMP levels, and trigger apoptosis in SK-MEL-3 cells. Collectively, the findings demonstrated a distinct pattern for the synthesized bimetallic nanocomposites. Furthermore, these nanocomposites also displayed significant (p
Fulltext Impact of Pharmacist-Led Interventions on Medication Adherence and Clinical Outcomes in Patients with Hypertension and Hyperlipidemia: A Scoping Review of Published Literature

Elnaem MH, Rosley NFF, Alhifany AA, Elrggal ME, Cheema E

J Multidiscip Healthc, 2020;13:635-645.
PMID: 32764955 DOI: 10.2147/JMDH.S257273

BACKGROUND: The aim of this study was to provide a scoping review of the impact of pharmacist-led interventions on medication adherence and clinical outcomes in patients with hypertension and hyperlipidemia.
METHODS: A scoping review was conducted using pre-defined search terms in three scientific databases, including Google Scholar, ScienceDirect, and PubMed. A multi-stage screening process that considered relevancy, publication year (2009-2019), English language, and article type (original research) was followed. Review articles, meta-analysis studies, and conference proceedings were excluded. Data charting was done in an iterative process using a study-specific extraction form.
RESULTS: Of the initially identified 681 studies, 17 studies with 136,026 patients were included in the review. Of these, 16 were randomized controlled trials, while the remaining study was a retrospective cohort study. The majority of pharmacist-led interventions were face-to-face counseling sessions (n=8), followed by remote- or telephone-based interventions (n=5) and multi-faceted interventions (n=4). The majority of the studies (n=7) used self-reported adherence measures and pharmacy refill records (n=8) to measure the rate of adherence to prescribed medications. Eleven of the included studies reported a statistically significant (P<0.05) impact on medication adherence. Overall, twelve studies assessed the effect of the interventions on the clinical outcome measures; of these, only four studies were associated with significant impact.
CONCLUSION: Pharmacist-led interventions were associated with improved patients' adherence to their medications but were less likely to be consistently associated with the attainment of clinical outcomes. Face-to-face counseling was the most commonly used intervention; while, the multi-faceted interventions were more likely to be effective in improving the overall outcome measures. The rigorous design of targeted interventions with more frequent follow-ups, careful consideration of the involved medications, and patients' characteristics could increase the effectiveness of these interventions.
Facile construction of gefitinib-loaded zeolitic imidazolate framework nanocomposites for the treatment of different lung cancer cells

Aiyasamy K, Ramasamy M, Hirad AH, Arulselvan P, Jaganathan R, Suriyaprakash J, et al.

Biotechnol Appl Biochem, 2024 Apr 09.
PMID: 38594878 DOI: 10.1002/bab.2585

Gefitinib (GET) is a revolutionary targeted treatment inhibiting the epidermal growth factor receptor's tyrosine kinase action by competitively inhibiting the ATP binding site. In preclinical trials, several lung cancer cell lines and xenografts have demonstrated potential activity with GET. Response rates neared 25% in preclinical trials for non-small cell lung cancer. Here, we describe the one-pot synthesis of GET@ZIF-8 nanocomposites (NCs) in pure water, encapsulating zeolitic imidazolate framework 8 (ZIF-8). This method developed NCs with consistent morphology and a loading efficiency of 9%, resulting in a loading capacity of 20 wt%. Cell proliferation assay assessed the anticancer effect of GET@ZIF-8 NCs on A549 and H1299 cells. The different biochemical staining (Calcein-AM and PI and 4',6-Diamidino-2-phenylindole nuclear staining) assays assessed the cell death and morphological examination. Additionally, the mode of apoptosis was evaluated by mitochondrial membrane potential (∆ψm) and reactive oxygen species. Therefore, the study concludes that GET@ZIF-8 NCs are pledged to treat lung cancer cells.
Fulltext Monte Carlo method with heuristic adjustment for irregularly shaped food product volume measurement

Siswantoro J, Prabuwono AS, Abdullah A, Idrus B

ScientificWorldJournal, 2014;2014:683048.
PMID: 24892069 DOI: 10.1155/2014/683048

Volume measurement plays an important role in the production and processing of food products. Various methods have been proposed to measure the volume of food products with irregular shapes based on 3D reconstruction. However, 3D reconstruction comes with a high-priced computational cost. Furthermore, some of the volume measurement methods based on 3D reconstruction have a low accuracy. Another method for measuring volume of objects uses Monte Carlo method. Monte Carlo method performs volume measurements using random points. Monte Carlo method only requires information regarding whether random points fall inside or outside an object and does not require a 3D reconstruction. This paper proposes volume measurement using a computer vision system for irregularly shaped food products without 3D reconstruction based on Monte Carlo method with heuristic adjustment. Five images of food product were captured using five cameras and processed to produce binary images. Monte Carlo integration with heuristic adjustment was performed to measure the volume based on the information extracted from binary images. The experimental results show that the proposed method provided high accuracy and precision compared to the water displacement method. In addition, the proposed method is more accurate and faster than the space carving method.
A questionnaire-based study on parental satisfaction with a universal newborn hearing screening program in Kuala Lumpur, Malaysia

Mazlan R, Ting TL, Mukari SZ, Abdullah A

Int J Pediatr Otorhinolaryngol, 2014 Feb;78(2):348-53.
PMID: 24380662 DOI: 10.1016/j.ijporl.2013.12.014

The present study aimed to determine levels of parents' satisfaction associated with the universal newborn hearing screening process in a university hospital setting in Kuala Lumpur, Malaysia.
A novel high throughput method based on the DPPH dry reagent array for determination of antioxidant activity

Musa KH, Abdullah A, Kuswandi B, Hidayat MA

Food Chem, 2013 Dec 15;141(4):4102-6.
PMID: 23993591 DOI: 10.1016/j.foodchem.2013.06.112

A stable chromogenic radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) is commonly used for the determination of antioxidant activity. In this paper, DPPH was dried into 96 well microplate to produce DPPH dry reagent array plate, based on which the highly sensitive and high throughput determination of antioxidant activities was achieved. The spectrophotometric characterization of the microplate containing dried or fresh DPPH free radicals was reported. The response of the DPPH dry reagent array towards different standard antioxidants was studied. The reaction for DPPH in fresh or dry reagent array with Trolox was reported and compared. The DPPH dry reagent array was used to study the antioxidant activity of banana, green tea, pink guava, and honeydew and the results were compared to the samples reacted with freshly prepared DPPH. The proposed method is comparable to the classical DPPH method, more convenient, simple to operate with minimal solvent required and excellent sensitivity.
Enhanced photodegradation of o-cresol in aqueous Mn(1%)-doped ZnO suspensions

Abdollahi Y, Abdullah AH, Gaya UI, Zainal Z, Yusof NA

Environ Technol, 2012 Jun;33(10-12):1183-9.
PMID: 22856288

The effective removal of o-cresol is currently both an environmental and economic challenge. ZnO is not only an efficient photocatalyst but is also cost effective, as its photoabsorption can extend from the ultraviolet (UV) to the visible range thereby allowing the use of inexpensive visible light sources, such as sunlight. The principal objective of the present work is to investigate the visible light-driven removal of o-cresol from aqueous solution in the presence of 1.0 wt% Mn-doped ZnO. To measure the efficiency ofphotodegradation, the variables studied included the amount ofphotocatalyst, concentration of o-cresol, pH and irradiation time. The concentration ofo-cresol and residual organic carbon was monitored using a UV-visible spectrophotometer, ultra high-pressure liquid chromatography and a total organic carbon analyser. The optimum conditions under which the photodegradation of o-cresol was most favourable corresponded to 1.5 g/l ZnO, 35 ppm o-cresol and pH 9. The ZnO-1 wt% Mn photoprocess has demonstrated reusability for more than three times, which warrants its scale-up from laboratory- to in industrial-scale application.
Fulltext Gold nanonetwork film on the ITO surface exhibiting one-dimensional optical properties

Umar AA, Iwantono I, Abdullah A, Salleh MM, Oyama M

Nanoscale Res Lett, 2012;7(1):252.
PMID: 22587640 DOI: 10.1186/1556-276X-7-252

A network of gold nanostructures exhibiting one-dimensional gold nanostructure properties may become a prospective novel structure for optical, electrical and catalytic applications benefited by its unusual characteristics resulting from the collective properties of individual nanostructures in the network. In this paper, we demonstrate a facile method for the formation of high-density gold nanonetwork film on the substrate surface composed of quasi-1D nanoparticles (typically fusiform) with length ca. 10 nm - via reduction of gold ions in the presence of nanoseeds attached surface, binary surfactants of cetyltrimethylammonium bromide and hexamethyleneteramine and Ag+ ions. The length of the nanonetworks can be up to ca. 100 nm, which corresponds to the aspect ratio of ca. 10. The quasi-1D gold nanostructures as well as the nanonetworks were found to be sensitive to the binary surfactants system and the Ag+ ions as they can only be formed if all the chemicals are available in the reaction. The nanonetworks exhibit unique 1D optical properties with the presence of transverse and longitudinal surface plasmon resonance absorption. Owing to their peculiar structures that are composed of small quasi-1D nanoparticles, the nanonetworks may produce unusual optical and catalytic properties, which are potentially used in surface-enhanced Raman scattering, catalysis and optical and non-linear optical applications.
Fulltext School scoliosis screening programme-a systematic review

Sabirin J, Bakri R, Buang SN, Abdullah AT, Shapie A

Med J Malaysia, 2010 Dec;65(4):261-7.
PMID: 21901941

A systematic review on the effectiveness and cost-effectiveness of school scoliosis screening programme was carried out. A total of 248 relevant titles were identified, 117 abstracts were screened and 28 articles were included in the results. There was fair level of evidence to suggest that school scoliosis screening programme is safe, contributed to early detection and reduction of surgery. There was also evidence to suggest that school-based scoliosis screening programme is cost-effective. Based on the above review, screening for scoliosis among school children is recommended only for high risk group such as girls at twelve years of age.
Keywords: Systematic review, scoliosis screening
Effects of background noise on recording of portable transient-evoked otoacoustic emission in newborn hearing screening

Salina H, Abdullah A, Mukari SZ, Azmi MT

Eur Arch Otorhinolaryngol, 2010 Apr;267(4):495-9.
PMID: 19727788 DOI: 10.1007/s00405-009-1080-y

Transient-evoked otoacoustic emission (TEOAE) is a well-established screening tool for universal newborn hearing screening. The aims of this study are to measure the effects of background noise on recording of TEOAE and the duration required to complete the test at various noise levels. This study is a prospective study from June 2006 until May 2007. The study population were newborns from postnatal wards who were delivered at term pregnancy. Newborns who were more than 8-h old and passed a hearing screening testing using screening auditory brainstem response (SABRe) were further tested with TEOAE in four different test environments [isolation room in the ward during non-peak hour (E1), isolation room in the ward during peak hour (E2), maternal bedside in the ward during non-peak hour (E3) and maternal bedside in the ward during peak hour (E4)]. This study showed that test environment significantly influenced the time required to complete testing in both ears with F [534.23] = 0.945; P < 0.001 on the right ear and F [636.54] = 0.954; P < 0.001 on the left. Our study revealed that TEOAE testing was efficient in defining the presence of normal hearing in our postnatal wards at maternal bedside during non-peak hour with a specificity of 96.8%. Our study concludes that background noise levels for acceptable and accurate TEOAE recording in newborns should not exceed 65 dB A. In addition, when using TEOAE assessment in noisy environments, the time taken to obtain accurate results will greatly increase.

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