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Catalytic cracking of bio-oil to organic liquid product (OLP)

Hew KL, Tamidi AM, Yusup S, Lee KT, Ahmad MM

Bioresour Technol, 2010 Nov;101(22):8855-8.
PMID: 20621470 DOI: 10.1016/j.biortech.2010.05.036

The main objective of this paper is to find the optimum operating condition to upgrade the EFB-derived pyrolysis oil (bio-oil) to liquid fuel, mainly gasoline using Taguchi Method. From the analysis that has been done, it is found that the optimum operating condition for heterogeneous catalytic cracking process is at 400 degrees C, 15min of reaction time using 30g of catalyst weight where operating at this condition produced the highest yield of gasoline fraction which is 91.67 wt.%. This observation proves that EFB-derived pyrolysis oil could be upgraded via heterogeneous catalytic cracking to produce gasoline.
The adsorption of heavy metal by Bornean oil palm shell and its potential application as constructed wetland media

Chong HL, Chia PS, Ahmad MN

Bioresour Technol, 2013 Feb;130:181-6.
PMID: 23306127 DOI: 10.1016/j.biortech.2012.11.136

Oil palm shell, a waste from palm oil industry, was cleaned and utilized as adsorbent. Its particle size distribution gave the uniformity coefficient of approximately two indicating that it can be used as filter bed media for continuous operation without resting. Its measured pH(pzc) of 4.1 is below the common pH of constructed wetland water body suggesting positive adsorption for heavy metal. The effect of various parameters on its adsorption was studied via batch experiments. The adsorption of Cu(II) and Pb(II) ions by oil palm shell showed a slightly better fit with the Freundlich compared to Langmuir. Its monolayer adsorption capacities were found to be 1.756 and 3.390mg/g for Cu(II) and Pb(II), respectively. High correlation coefficient of over 0.99 given by the pseudo-second-order model suggests that the rate limiting factor may be chemisorption. These findings suggest its potential application as constructed wetland media for the removal of heavy metal.
Sustainable wastewater treatment by biochar/layered double hydroxide composites: Progress, challenges, and outlook

Zubair M, Ihsanullah I, Abdul Aziz H, Azmier Ahmad M, Al-Harthi MA

Bioresour Technol, 2021 Jan;319:124128.
PMID: 32979597 DOI: 10.1016/j.biortech.2020.124128

Biochar/layered double hydroxide (LDH) composites have gained considerable attention in recent times as low-cost sustainable materials for applications in water treatment. This paper critically evaluates the latest development in applications of biochar/LDH composites in water treatment with an emphasis on adsorption and catalytic degradation of various pollutants. The adsorption of various noxious contaminants, i.e., heavy metals, dyes, anions, and pharmaceuticals onto biochar/LDH composites are described in detail by elaborating the adsorption mechanism and regeneration ability. The synergistic effect of LDH with biochar exhibited significant improvement in specific surface area, surface functional groups, structure heterogeneity, stability, and adsorption characteristics of the resulting biochar/LDH composites. The major hurdles and challenges associated with the synthesis and applications of biochar/LDH composites in water remediation are emphasized. Finally, a roadmap is suggested for future research to assure the effective applications of biochar/LDH composites in water purification.
A practical approach for synthesis of biodiesel via non-edible seeds oils using trimetallic based montmorillonite nano-catalyst

Munir M, Ahmad M, Mubashir M, Asif S, Waseem A, Mukhtar A, et al.

Bioresour Technol, 2021 May;328:124859.
PMID: 33621759 DOI: 10.1016/j.biortech.2021.124859

The potential of new trimetallic (Ce, Cu, La) loaded montmorillonite clay catalyst for synthesizing biodiesel using novel non-edible Celastrus paniculatus Willd seed oil via two-step transesterification reaction has been reported along with catalyst characterization. Transesterification reaction was optimized and maximum biodiesel yield of 89.42% achieved under optimal operating reaction states like; 1:12 oil to methanol ratio, 3.5% of catalyst amount, 120 °C of reaction temperature for 3 h. The predicted and experimental biodiesel yields under these reaction conditions were 89.42 and 89.40%, which showing less than 0.05% variation. Additionally, optimum biodiesel yield can be predicted by drawing 3D surface plots and 2D contour plots using MINITAB 17 software. For the characterization of the obtained biodiesel, analysis including the GC/MS, FT-IR, 1H NMR and 13C NMR were applied. The fuel properties of obtained biodiesel agrees well with the different European Union (EU-14214), China (GB/T 20828), and American (ASTM-951, 6751) standards.
Phyllosilicate derived catalysts for efficient conversion of lignocellulosic derived biomass to biodiesel: A review

Nawaz S, Ahmad M, Asif S, Klemeš JJ, Mubashir M, Munir M, et al.

Bioresour Technol, 2022 Jan;343:126068.
PMID: 34626762 DOI: 10.1016/j.biortech.2021.126068

The efforts have been made to review phyllosilicate derived (clay-based) heterogeneous catalysts for biodiesel production via lignocellulose derived feedstocks. These catalysts have many practical and potential applications in green catalysis. Phyllosilicate derived heterogeneous catalysts (modified via any of these approaches like acid activated clays, ion exchanged clays and layered double hydroxides) exhibits excellent catalytic activity for producing cost effective and high yield biodiesel. The combination of different protocols (intercalated catalysts, ion exchanged catalysts, acidic activated clay catalysts, clay-supported catalysts, composites and hybrids, pillared interlayer clay catalysts, and hierarchically structured catalysts) was implemented so as to achieve the synergetic effects (acidic-basic) in resultant material (catalyst) for efficient conversion of lignocellulose derived feedstock (non-edible oils) to biodiesel. Utilisation of these Phyllosilicate derived catalysts will pave path for future researchers to investigate the cost-effective, accessible and improved approaches in synthesising novel catalysts that could be used for converting lignocellulosic biomass to eco-friendly biodiesel.
A scaffoldless technique for self-generation of three-dimensional keratinospheroids on liquid crystal surfaces

Soon CF, Thong KT, Tee KS, Ismail AB, Denyer M, Ahmad MK, et al.

Biotech Histochem, 2016 May;91(4):283-95.
PMID: 27008034 DOI: 10.3109/10520295.2016.1158865

We describe a new scaffold-free three-dimensional (3D) cell culture model using cholesteryl ester based lyotropic liquid crystal (LC) substrates. Keratinocytes were deposited randomly on the LC surface where they self-assembled into 3D microtissues or keratinospheroids. The cell density required to form spheroids was optimized. We investigated cell viability using dead/live cell assays. The adhesion characteristics of cells within the microtissues were determined using histological sectioning and immunofluorescence staining. Fourier transform infrared spectroscopy (FTIR) was used to characterize the biochemistry of the keratinospheroids. We found that both cells and microtissues could migrate on the LC surface. The viability study indicated approximately 80% viability of cells in the microtissues up to 20 days of culture. Strong intercellular adhesion was observed in the stratification of the multi-layered microspheroids using field emission-scanning electron microscopy (FE-SEM) and histochemical staining. The cytoskeleton and vinculins of the cells in the microtissues were expressed diffusely, but the microtissues were enriched with lipids and nucleic acids, which indicates close resemblance to the conditions in vivo. The basic 3D culture model based on LC may be used for cell and microtissue migration studies in response to cytochemical treatment.
Fulltext Cutaneous leishmaniasis-Awareness, knowledge and practices among general population in rural and urban areas in Malakand region, Pakistan

Khan W, Khan I, Ullah H, Zain SNM, Panhwar WA, Mehmood SA, et al.

Braz J Biol, 2021;82:e238665.
PMID: 33787717 DOI: 10.1590/1519-6984.238665

Malakand region is an endemic area for cutaneous leishmaniasis (CL). However, there are limited number of studies of this disease in Pakistan. Therefore, a study was conducted to understand the level of awareness attitude and practice among the residents of Makaland towards CL and the disease vectors. This study adopted a cross-sectional approach with a total of 400 respondents (n=93 rural and n= 307 urban). Overall, the population in Malakand region (61.2%) were well-informed in the role of sand fly in transmitting diseases, but most lack knowledge on the vector's behavior and almost a quarter (24.5%) were unable to provide knowledge on proper control measures. Alarmingly, the practice and attitudes of the general population was not satisfactory as close to half (49.8%) of the population did adopt any control method. This study calls for increase in awareness through health education campaign to reduce the risk of cutaneous leishmaniasis outbreaks in the future.
FOXP3 regulatory T cells on prognosis of breast cancer

Usman AN, Ahmad M, Sinrang AW, Natsir S, Takko AB, Ariyandy A, et al.

Breast Dis, 2023;42(1):213-218.
PMID: 37458005 DOI: 10.3233/BD-239002

BACKGROUND: FOXP3 Tregs have been found in breast cancer patients, both humoral and tumor. Survival or prognosis of breast cancer patients seems to correlate with the increase and decrease in FOXP3 Treg.
OBJECTIVES: This review aims to provide insights regarding the FOXP3 Tregs involved and their mechanisms in breast cancer prognosis.
METHODS: The literature study method is used from primary and secondary libraries. The library search used online-based search instruments such as NCBI-PubMed, Google Scholar, and Elsevier. The data obtained were then arranged according to the framework, data on the relationship between FOXP3 Regulatory T Cells and breast cancer, and writing a journal review was carried out according to the given format. Regulators (Tregs) can inhibit anti-tumor immunity and promote tumor growth. Tregs also play a role in inhibiting cytotoxic T lymphocyte cells by inhibiting the release of granules from CD8+, where CD8+ is important in killing tumor cells. FOXP3 is a Treg-specific biomarker and plays an important role in the development and function of Tregs.
RESULTS: Studies on the presence of FOXP3+ Tregs in tumors have shown controversial results. Studies in some tumors reported the presence of FOXP3+, indicating a poor prognosis, whereas studies in other tumors found that FOXP3+ correlated with a good prognosis.
CONCLUSION: Regulatory T lymphocytes and TILs in invasive breast carcinoma are still not established. Therefore, further research on the Effect of FOXP3 expression of regulatory T lymphocytes on breast cancer is still important.
Ginger potency on the prevention and treatment of breast cancer

Usman AN, Manju B, Ilhamuddin I, Ahmad M, Ab T, Ariyandy A, et al.

Breast Dis, 2023;42(1):207-212.
PMID: 37424457 DOI: 10.3233/BD-239003

BACKGROUND: Cancer is a type of disease caused by the uncontrolled growth of abnormal cells that can destroy body tissues. The use of traditional medicine naturally uses plants from ginger with the maceration method. The ginger plant is a herbaceous flowering plant with the Zingiberaceacea group.
METHODS: This study uses the literature review method by reviewing 50 articles from journals and databases.
RESULTS: A review of several articles, namely ginger has bioactive components such as gingerol. Ginger is used as a treatment in complementary therapies using plants. Ginger is a strategy with many benefits and functions as a nutritional complement to the body. This benefit has shown the effect of anti-inflammatory, antioxidant, and anticancer against nausea and vomiting due to chemotherapy in breast cancer.
CONCLUSION: Anticancer in ginger is shown by polyphenols associated with anti-metastatic, anti-proliferative, antiangiogenic, anti-inflammatory, cell cycle arrest, apoptosis, and autophagy. Therefore, consuming ginger regularly affects natural herbal therapy with the prevention and treatment of breast cancer and serves as a prevention against the effects of chemotherapy.
Improving magnetic resonance imaging (MRI) examinations: Development and evaluation of an intervention to reduce movement in scanners and facilitate scan completion

Powell R, Ahmad M, Gilbert FJ, Brian D, Johnston M

Br J Health Psychol, 2015 Sep;20(3):449-65.
PMID: 25639980 DOI: 10.1111/bjhp.12132

The movement of patients in magnetic resonance imaging (MRI) scanners results in motion artefacts which impair image quality. Non-completion of scans leads to delay in diagnosis and increased costs. This study aimed to develop and evaluate an intervention to enable patients to stay still in MRI scanners (reducing motion artefacts) and to enhance scan completion. Successful scan outcome was deemed to be completing the scan with no motion artefacts.
Fulltext Telemedicine to deliver diabetes care in low- and middle-income countries: a systematic review and meta-analysis

Correia JC, Meraj H, Teoh SH, Waqas A, Ahmad M, Lapão LV, et al.

Bull World Health Organ, 2021 Mar 01;99(3):209-219B.
PMID: 33716343 DOI: 10.2471/BLT.19.250068

Objective: To determine the effectiveness of telemedicine in the delivery of diabetes care in low- and middle-income countries.
Methods: We searched seven databases up to July 2020 for randomized controlled trials investigating the effectiveness of telemedicine in the delivery of diabetes care in low- and middle-income countries. We extracted data on the study characteristics, primary end-points and effect sizes of outcomes. Using random effects analyses, we ran a series of meta-analyses for both biochemical outcomes and related patient properties.
Findings: We included 31 interventions in our meta-analysis. We observed significant standardized mean differences of -0.38 for glycated haemoglobin (95% confidence interval, CI: -0.52 to -0.23; I2 = 86.70%), -0.20 for fasting blood sugar (95% CI: -0.32 to -0.08; I2 = 64.28%), 0.81 for adherence to treatment (95% CI: 0.19 to 1.42; I2 = 93.75%), 0.55 for diabetes knowledge (95% CI: -0.10 to 1.20; I2 = 92.65%) and 1.68 for self-efficacy (95% CI: 1.06 to 2.30; I2 = 97.15%). We observed no significant treatment effects for other outcomes, with standardized mean differences of -0.04 for body mass index (95% CI: -0.13 to 0.05; I2 = 35.94%), -0.06 for total cholesterol (95% CI: -0.16 to 0.04; I2 = 59.93%) and -0.02 for triglycerides (95% CI: -0.12 to 0.09; I2 = 0%). Interventions via telephone and short message service yielded the highest treatment effects compared with services based on telemetry and smartphone applications.
Conclusion: Although we determined that telemedicine is effective in improving several diabetes-related outcomes, the certainty of evidence was very low due to substantial heterogeneity and risk of bias.
Fulltext Evaluation of stem-like side population cells in a recurrent nasopharyngeal carcinoma cell line

Hoe SL, Tan LP, Jamal J, Peh SC, Ng CC, Zhang WC, et al.

Cancer Cell Int, 2014;14(1):101.
PMID: 25317078 DOI: 10.1186/s12935-014-0101-0

Side population (SP) assay identifies cells with dye/drug extrusion ability, a characteristic of stem cells. Here, we determined if SP cells exist in a verified cell line originating from recurrent nasopharyngeal carcinoma (NPC) and a xenograft established from recurrent metastatic NPC. These cells were evaluated for stem-like properties via functional assays as well as for tumourigenicity.
Quercetin-induced inhibition and synergistic activity with cisplatin - a chemotherapeutic strategy for nasopharyngeal carcinoma cells

Daker M, Ahmad M, Khoo AS

Cancer Cell Int, 2012;12(1):34.
PMID: 22809533

Nasopharyngeal carcinoma (NPC) is a unique tumour of epithelial origin with a distinct geographical distribution, genetic predisposition and environmental as well as dietary influence as aetiological factors. Standard NPC treatment regimes, such as radiotherapy and concurrent chemotherapy with cytotoxic drugs, can produce undesirable complications often associated with significant toxicity. Here, we report the effects of a widely distributed flavonoid, quercetin, on cell proliferation, apoptosis and cell cycle arrest. The effects of combining quercetin and cisplatin on human NPC cells were explored.
Parallel genome-wide RNAi screens identify lymphocyte-specific protein tyrosine kinase (LCK) as a targetable vulnerability of cell proliferation and chemoresistance in nasopharyngeal carcinoma

Liew K, Yu GQS, Wei Pua LJ, Wong LZ, Tham SY, Hii LW, et al.

Cancer Lett, 2021 Apr 28;504:81-90.
PMID: 33587980 DOI: 10.1016/j.canlet.2021.02.006

Despite recent in advances in the management of nasopharyngeal carcinoma (NPC), development of targeted therapy remains challenging particularly in patients with recurrent or metastatic disease. To search for clinically relevant targets for the treatment of NPC, we carried out parallel genome-wide functional screens to identified essential genes that are required for NPC cells proliferation and cisplatin resistance. We identified lymphocyte-specific protein tyrosine kinase (LCK) as a key vulnerability of both proliferation and cisplatin resistance. Depletion of endogenous LCK or treatment of cells with LCK inhibitor induced tumor-specific cell death and synergized cisplatin sensitivity in EBV-positive C666-1 and EBV-negative SUNE1 cells. Further analyses demonstrated that LCK is regulating the proliferation and cisplatin resistance through activation of signal transducer and activator of transcription 5 (STAT5). Taken together, our study provides a molecular basis for targeting LCK and STAT5 signaling as potential druggable targets for the management of NPC.
Electrochemical exfoliation of graphite in nanofibrillated kenaf cellulose (NFC)/surfactant mixture for the development of conductive paper

Ardyani T, Mohamed A, Abu Bakar S, Sagisaka M, Umetsu Y, Hafiz Mamat M, et al.

Carbohydr Polym, 2020 Jan 15;228:115376.
PMID: 31635739 DOI: 10.1016/j.carbpol.2019.115376

The effect of incorporating common dodecyl anionic and cationic surfactants such as dodecyltrimethylammonium bromide (DTAB), dodecylethyldimethylammonium bromide (DDAB), and sodium dodecylsulfate (SDS) in nanocomposites of reduced graphene oxide and nanocellulose are described. The stabilization and electrical properties of the nanocomoposites of reduced graphene oxide (RGO) and nanofibrillated kenaf cellulose (NFC) were characterized using four-point probe electrical conductivity measurements. Raman spectroscopy, field emission scanning electron microscopy, and high-resolution transmission electron microscopy were used to investigate dispersion morphology and the quality of RGO inside the NFC matrices. Small-angle neutron scattering (SANS) was used to study the aggregation behavior of the aqueous surfactant systems and RGO dispersions. The cationic surfactant DTAB proved to be the best choice for stabilization of RGO in NFC, giving enhanced electrical conductivity five orders of magnitude higher than the neat NFC. The results highlight the effects of hydrophilic surfactant moieties on the structure, stability and properties of RGO/NFC composites.
Global Study of Social Odor Awareness

Sorokowska A, Groyecka A, Karwowski M, Frackowiak T, Lansford JE, Ahmadi K, et al.

Chem. Senses, 2018 08 24;43(7):503-513.
PMID: 29955865 DOI: 10.1093/chemse/bjy038

Olfaction plays an important role in human social communication, including multiple domains in which people often rely on their sense of smell in the social context. The importance of the sense of smell and its role can however vary inter-individually and culturally. Despite the growing body of literature on differences in olfactory performance or hedonic preferences across the globe, the aspects of a given culture as well as culturally universal individual differences affecting odor awareness in human social life remain unknown. Here, we conducted a large-scale analysis of data collected from 10 794 participants from 52 study sites from 44 countries all over the world. The aim of our research was to explore the potential individual and country-level correlates of odor awareness in the social context. The results show that the individual characteristics were more strongly related than country-level factors to self-reported odor awareness in different social contexts. A model including individual-level predictors (gender, age, material situation, education, and preferred social distance) provided a relatively good fit to the data, but adding country-level predictors (Human Development Index, population density, and average temperature) did not improve model parameters. Although there were some cross-cultural differences in social odor awareness, the main differentiating role was played by the individual differences. This suggests that people living in different cultures and different climate conditions may still share some similar patterns of odor awareness if they share other individual-level characteristics.
Fulltext Reaction of 2,6-dichloroquinone-4-chloroimide (Gibbs reagent) with permethrin - an optical sensor for rapid detection of permethrin in treated wood

Arip MN, Heng LY, Ahmad M, Hasbullah SA

Chem Cent J, 2013;7:122.
PMID: 23867006 DOI: 10.1186/1752-153X-7-122

A novel optical sensor for the rapid and direct determination of permethrin preservatives in treated wood was designed. The optical sensor was fabricated from the immobilisation of 2,6-dichloro-p-benzoquinone-4-chloroimide (Gibbs reagent) in nafion/sol-gel hybrid film and the mode of detection was based on absorption spectrophotometry. Physical entrapment was employed as a method of immobilisation.
Fulltext A study on dispersion and characterisation of α-mangostin loaded pH sensitive microgel systems

Ahmad M, Yamin BM, Mat Lazim A

Chem Cent J, 2013;7:85.
PMID: 23680098 DOI: 10.1186/1752-153X-7-85

α-Mangostin was extracted with methanol from the rind of mangosteen fruit and purified by using silica gel column chromatography technique. The compound is characterised using infrared, (13)C and (1)H NMR as well as UV-vis spectroscopy. The α-mangostin dispersion in colloidal systems was studied by incorporating it with an ionic microgel, poly (N-Isopropylacrylamide)-co-2VP at different pH.
Fulltext Antibacterial activity of silver bionanocomposites synthesized by chemical reduction route

Bin Ahmad M, Lim JJ, Shameli K, Ibrahim NA, Tay MY, Chieng BW

Chem Cent J, 2012;6(1):101.
PMID: 22967920 DOI: 10.1186/1752-153X-6-101
Synthesis of biodiesel from non-edible (Brachychiton populneus) oil in the presence of nickel oxide nanocatalyst: Parametric and optimisation studies

Dawood S, Koyande AK, Ahmad M, Mubashir M, Asif S, Klemeš JJ, et al.

Chemosphere, 2021 Sep;278:130469.
PMID: 33839393 DOI: 10.1016/j.chemosphere.2021.130469

The present study defines a novel green method for the synthesis of the nickel oxide nanocatalyst by using an aqueous latex extract of the Ficus elastic. The catalyst was examined for the conversion of novel Brachychiton populneus seed oil (BPSO) into biodiesel. The Brachychiton populneus seeds have a higher oil content (41 wt%) and free fatty acid value (3.8 mg KOH/g). The synthesised green nanocatalyst was examined by the Fourier transform infrared (FT-IR) spectroscopy, energy dispersive X-Ray (EDX) spectroscopy, X-Ray diffraction (XRD) spectroscopy and scanning electron microscopy (SEM). The obtained results show that the synthesised green nanocatalyst was 22-26 nm in diameter and spherical-cubic in shape with a higher rate of catalytic efficiency. It was utilised further for the conversion of BPSO into biofuel. Due to the high free fatty acid value, the biodiesel was synthesised by the two-step process, i.e., pretreatment of the BPSO by means of acid esterification and then followed by the transesterification reaction. The acidic catalyst (H2SO4) was used for the pretreatment of BPSO. The optimum condition for the transesterification of the pretreated BPSO was 1:9 of oil-methanol molar ratio, 2.5 wt % of prepared nanocatalyst concentration and 85 °C of reaction temperature corresponding to the highest biodiesel yield of 97.5 wt%. The synthesised biodiesel was analysed by the FT-IR and GC-MS technique to determine the chemical composition of fatty acid methyl esters. Fuel properties of Brachychiton populneus seed oil biodiesel (BPSOB) were also examined, compared, and it falls in the prescribed range of ASTM standards.

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