320 research outputs found
In vitro pro-apoptotic and anti-migratory effects of Marantodes pumilum (Blume) Kuntze and Ficus deltoidea L. extracts on prostate cancer cell lines
This thesis evaluates the in vitro pro-apoptotic and anti-migratory effects of Marantodes pumilum Blume Kuntze and Ficus deltoidea L. plants on prostate cancer cells, characterising both their mechanism of actions on some of the main Hallmarks of Cancer, and their chemistry with a view to contribute to future chemopreventive strategies. Plant materials of M. pumilum (MP) F. deltoidea var. angustifolia (FD1) and F. deltoidea var. deltoidea (FD2) were obtained from dedicated farms in Southern Malaysia. The crude methanolic extract was partitioned into n-hexane (MPh, FD1h, FD2h) chloroform (MPc, FD1c, FD2c) and aqueous extracts (MPa, FD1a, FD2a). Active fractions (GI50<30 μg/mL) based on prostate cancer cell line, PC3, Sulforhodamine B staining were further fractionated. Active compound/s were identified using spectroscopic methods. In vitro mechanistic studies on PC3 cells were conducted to investigate the mode of death of PC3 cells and effects of the active extracts on PC3 cells migration and invasion. MPc, FD1c and FD2c extracts induced cell death via apoptosis as evidenced by nuclear DNA fragmentation, accompanied by a significant increase in MMP depolarization (P<0.05), activation of caspases 3 and 7 (MPc P<0.01; FD1c and FD2c P<0.05) in both PC3 and LNCaP cell lines. All active plant extracts up-regulated Bax and Smac/DIABLO and down-regulated Bcl-2 (P<0.05). Only MPc inhibited the expression of ALOX-5 mRNA gene expression (P<0.001). None resulted cytotoxic against normal human fibroblast cells (HDFa) at the tested concentrations. All active plant extracts inhibited both migration and invasion of PC3 cells (MPc; P<0.01, FD1c and FD2c; P<0.05), achieved by down-regulation of both VEGF and CXCL-12 gene expressions (P<0.001). A monounsaturated 5-alkyl resorcinol was isolated as the active compound present in the MPc extract. LC-MS dereplication identified isovitexin in FD1c; and oleanolic acid, moretenol, betulin, lupenone and lupeol in FD2c. In conclusion, evidence gathered in this study suggests a role for interaction of MPc, FD1c and FD2c in three of the Hallmarks of Cancer in PC3 cells: (1) apoptosis by activating of the intrinsic pathway, (2) inhibition of both migration and invasion by modulating the CXCL12-CXCR4 axis, and (3) inhibiting angiogenesis by modulating VEGF-A expression. The compounds identified and dereplicated in this study will be further characterized and used for the standardization of the active extracts in the future
Effect of Addition of Palm Oil Biodiesel in Waste Plastic Oil on Diesel Engine Performance, Emission, and Lubricity.
This research was aimed to examine the diesel engine's performance and emission of secondary fuels (SFs), comprising waste plastic oil (WPO) and palm oil biodiesel (POB), and to analyze their tribological properties. Their compositions were analyzed by gas chromatography-mass spectrometry (GC-MS). Five SFs (10-50% POB in WPO) were prepared by mechanical stirring. The results were compared to blank WPO (WPO100) and Malaysian commercial diesel (B10). WPO90 showed the maximum brake power (BP) and brake torque (BT) among the SFs, and their values were 0.52 and 0.59% higher compared to B10, respectively. The increase in POB ratio (20-50%) showed a negligible difference in BP and BT. WPO70 showed the lowest brake-specific fuel consumption among the SFs. The brake thermal efficiency (BTE) increased with POB composition. The maximum reductions in emission of hydrocarbon (HC, 37.21%) and carbon monoxide (CO, 27.10%) were achieved by WPO50 among the SFs. WPO90 showed the maximum reduction in CO2 emission (6.78%). Increasing the POB composition reduced the CO emissions and increased the CO2 emissions. All SFs showed a higher coefficient of friction (COF) than WPO100. WPO50 showed the minimal increase in COF of 2.45%. WPO90 showed the maximum reduction in wear scar diameter (WSD), by 10.34%, compared to B10. Among the secondary contaminated samples, SAE40-WPO90 showed the lowest COF, with 5.98% reduction compared to SAE40-WPO100. However, with increasing POB content in the secondary contaminated samples, the COF increased. The same trend was also observed in their WSD. Overall, WPO90 is the optimal SF with excellent potential for diesel engines
An Observation on the Effect of Semi-Elemental Oral Nutritional Supplements on the Reduction of Small Bowel Ostomy Output
Semi-elemental oral nutritional supplements are also referred to the oligomeric, hydrolysed or peptide formula, the nitrogen source of the formulas derived from hydrolyzed oligopeptide of shorter lengths such as the dipeptides and tripeptides. The ingredient of casein and lactaalbumin hydrolysates in this formula are believed to be capable of stimulating the jejunal absorption of water and electrolytes. The postulated stimulation of improves absorption increased our curiosity on its effect on those patient with high output ostomy. We understand that this formula is more costly compared to the other polymeric formula available in the market. We would like to share an observation of two ostomies output that are managed conservatively along with the supplementation of a semi-elemental formula. We retrospectively review the case notes of two patients with small bowel ostomies and graphs were plotted to demonstrate the relationship between the output and the intake of the semi-elemental formula. We observed an interesting pattern of the ostomy output in relationship to intake volume. The ostomy output decreases as the patients increase the intake of the semi-elemental formula. From our observation, we concluded that semi-elemental formula improved clinical nutrition outcome and also quality of life in terms of stoma output reduction, making the stoma care more manageable. However, we hope that through our observation case studies, we would encourage more researchers to conduct a larger prospective and clinical study to explore the true clinical effects and also cost-effectiveness of this formula
Influence of simulation in Malaysian healthcare education and research (ISIM-HERE): a two-decade experience
The use of simulation as a teaching methodology in medical institutions has been in Malaysia for over two decades. This study aimed to evaluate the current scenarios of simulation impact and utilization in Malaysian academic healthcare institutions (AHIs). We conducted a population-based survey on all AHIs in Malaysia including public and private. We performed an online survey followed by a face-to-face interview evaluating the number of institutions that used simulation, duration of experience, purpose, funding, users’ category and healthcare domain, research activities, dedicated-trained staff and the challenges faced. Out of 75 healthcare institutions approached, 38 agreed to participate in this study. Twenty-two (57.9%) were public hospitals while 16 (42.1%) were private institutions. Thirty-five (92.1%) out of 38 institutions used simulation as a teaching method. The majority (15, 42.9%) had less than five years’ experience, and about a third (11, 31.4%) used simulation for teaching, training and performance assessment. Nurses (30, 26.1%) were the main users followed by physicians and paramedic (19, 16.5% each respectively). In-hospital and procedural group were the top two domains of utilizers. Almost three quarters (25, 71.4%) have dedicated support staff to manage the centre. Funding was mainly from internal institutional support mechanisms. Seven different categories of challenges were identified, the biggest being financial support. In summary, even though healthcare simulation has been in Malaysia for the past two decades but the most substantial impact happened over the last five years. Utilization was mainly for teaching, training, and performance assessment with minimal use in research
Numerical simulations of vortex-induced vibrations on vertical cylindrical structure with different aspect ratios
This paper presents a computational fluid dynamics (CFD) study of vortex-induced vibration (VIV) for different aspect ratio (L/D) cylinder. Of particular interest was to measure hydrodynamic forces and numerically investigate the wake behaviour of VIV while varying the aspect ratio. The simulation models represented the actual experimental conditions with idealised free-surface boundary condition to capture the responses from fluid-structure interaction phenomenon. The simulations were performed in the subcritical flow region (7.4×103 < Re < 2×105), corresponding to a range of reduced velocity (Ur) from 2 to 14. The results of the cases studied were discussed and compared with the experimental data to verify the accuracy and validity of the present simulation. The comparisons have shown a similar curved-shape drag coefficient plot, and however underestimated the value of the drag coefficients over the reduced velocity. Additionally, the simulations seemed to capture a higher lift force response compared with the experimental data for a low aspect ratio. The correlation length was observed to be longer for larger aspect ratio and proportionally decreases as the aspect ratio decreases
Development of polymeric nanocomposite (Xyloglucan-co-Methacrylic acid/Hydroxyapatite/SiO 2 ) scaffold for bone tissue engineering applications—In-vitro antibacterial, cytotoxicity and cell culture evaluation
Advancement and innovation in bone regeneration, specifically polymeric composite scaffolds, are of high significance for the treatment of bone defects. Xyloglucan (XG) is a polysaccharide biopolymer having a wide variety of regenerative tissue therapeutic applications due to its biocompatibility, in-vitro degradation and cytocompatibility. Current research is focused on the fabrication of polymeric bioactive scaffolds by freeze drying method for nanocomposite materials. The nanocomposite materials have been synthesized from free radical polymerization using n-SiO2 and n-HAp XG and Methacrylic acid (MAAc). Functional group analysis, crystallinity and surface morphology were investigated by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM) techniques, respectively. These bioactive polymeric scaffolds presented interconnected and well-organized porous morphology, controlled precisely by substantial ratios of n-SiO2. The swelling analysis was also performed in different media at varying temperatures (27, 37 and 47 °C) and the mechanical behavior of the dried scaffolds is also investigated. Antibacterial activities of these scaffolds were conducted against pathogenic gram-positive and gram-negative bacteria. Besides, the biological behavior of these scaffolds was evaluated by the Neutral Red dye assay against the MC3T3-E1 cell line. The scaffolds showed interesting properties for bone tissue engineering, including porosity with substantial mechanical strength, biodegradability, biocompatibility and cytocompatibility behavior. The reported polymeric bioactive scaffolds can be aspirant biomaterials for bone tissue engineering to regenerate defecated bone
The study on range of motion of hip and knee in prayer by adult Muslim males. A preliminary report
Introduction: Praying represents a fundamental activity of daily living in Muslim community. Muslims need to adopt several postures that require deep flexion of the knee and hip to perform this daily obligation. This is a preliminary report of the study on hip and knee range of motion conducted to obtain normative passive and functional range of flexion data during Muslim prayers in both weight-bearing joints of normal Muslim adults. Methods: A cohort of Malay men aged between 20 to 30 years was recruited in this cross-sectional study. Passive range of motion and flexion angles of the joints in various postures during prayer were measured using a standard goniometer. The difference against existing normative range of motion database available and the influence of various factors were analysed. Factors analysed include body mass index and other anthropometric measurements. Results: Sixty participants recruited for the preliminary phase of this study. The mean (SD) of passive hip and knee flexions were higher compared to other existing normative range of motion database. A unit increase in body mass index will have 0.782 units lower of knee range of motion. The hip and knee flexion arc were from 74.1° to 119.0° and from 3.3° to 119.7° respectively. Conclusion: The range of motion involved for prayers was more for the knee but less for the hip as compared to the measured passive range of motion. Body mass index has a significant linear negative relationship with the passive range of motion of the knee, but not the hip
Neuroleptic malignant syndrome in an elderly patient with bipolar disorder
Neuroleptic malignant syndrome (NMS) is a well-known and potentially fatal
complication of antipsychotic use. The elderly population, with multiple risk
factors, are more vulnerable to this condition. We described a case of an 80-year-old man with bipolar disorder, previously on oral extended-release sodium
valproate, aripiprazole and long-acting injectable paliperidone, who developed
NMS. He presented with generalised muscle rigidity, fever, fluctuating blood
pressure and elevated creatinine kinase during his hospitalisation for a manic
episode. Contributing factors included old age, underlying vascular Parkinsonism,
electrolyte imbalance, intercurrent lung infection with acute exacerbation of chronic
obstructive pulmonary disease, hyperactive delirium, and repeated administration
of parenteral typical antipsychotic. Antipsychotics were withheld promptly, and the
patient was treated with dantrolene, bromocriptine and amantadine. His symptoms
resolved after a week. He subsequently remained well with oral extended-release
sodium valproate alone. Relevant clinical points are discussed. Clinical vigilance,
close interdisciplinary cooperation, and prompt interventions are keys to successful
to management of NMS in elderly patients
Optimizing the lateral beamforming step for filtered-delay multiply and sum beamforming to improve active contour segmentation using ultrafast ultrasound imaging
As an alternative to delay-and-sum beamforming, a novel beamforming technique called filtered-delay multiply and sum (FDMAS) was introduced recently to improve ultrasound B-mode image quality. Although a considerable amount of work has been performed to evaluate FDMAS performance, no study has yet focused on the beamforming step size, , in the lateral direction. Accordingly, the performance of FDMAS was evaluated in this study by fine-tuning to find its optimal value and improve boundary definition when balloon snake active contour (BSAC) segmentation was applied to a B-mode image in ultrafast imaging. To demonstrate the effect of altering in the lateral direction on FDMAS, measurements were performed on point targets, a tissue-mimicking phantom and in vivo carotid artery, by using the ultrasound array research platform II equipped with one 128-element linear array transducer, which was excited by 2-cycle sinusoidal signals. With 9-angle compounding, results showed that the lateral resolution (LR) of the point target was improved by 67.9% and 81.2%, when measured at −6 dB and −20 dB respectively, when was reduced from to . Meanwhile the image contrast ratio (CR) measured on the CIRS phantom was improved by 10.38 dB at the same reduction and the same number of compounding angles. The enhanced FDMAS results with lower side lobes and less clutter noise in the anechoic regions provides a means to improve boundary definition on a B-mode image when BSAC segmentation is applied
IFSS, TG, FT-IR spectra of impregnated sugar palm (Arenga pinnata) fibres and mechanical properties of their composites.
This study aimed to investigate the effect of resin impregnation on the interfacial shear strength (IFSS), thermogravimetric (TG) and fourier transform infrared (FT-IR) of sugar palm (Arenga pinnata) fibres. In addition, the effect of resin impregnation on the mechanical properties of sugar palm fibre reinforced unsaturated polyester (UP) composites was also studied. The fibres were impregnated with UP via vacuum resin impregnation process at a pressure of 600 mmHg for 5 min. Composites of 10, 20, 30, 40 and 50 % fibre loadings were fabricated and tested for tensile and flexural properties. It was observed that the impregnation process caused the fibres to be enclosed by UP resin and this gave a strong influence to the increase of its interfacial bonding by the increase of its IFSS from single fibre pull-out test. It was also observed with TG and FT-IR spectra that the impregnated fibre had lower moisture uptake than the control and there was no significant increase in thermal stability of the impregnated fibre. The sequence of fibre decomposition started from the evaporation of moisture, hemicelluloses, cellulose, lignin and finally ash content and the presence of these components were proven by FT-IR spectra. For the composite specimens, due to the high interfacial bonding of the impregnated fibre and the matrix, the impregnated composites showed consistently higher tensile strength, tensile modulus, elongation at break, flexural strength, flexural modulus and toughness than the control samples. It was also observed that 30 % fibre loading gave optimum properties
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