19672 research outputs found
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Integrative machine learning analysis of multiple gene expression profiles in cervical cancer
No full textAlthough most of the cervical cancer cases are reported to be closely related to the Human Papillomavirus (HPV) infection, there is a need to study genes that stand up differentially in the final actualization of cervical cancers following HPV infection. In this study, we proposed an integrative machine learning approach to analyse multiple gene expression profiles in cervical cancer in order to identify a set of genetic markers that are associated with and may eventually aid in the diagnosis or prognosis of cervical cancers. The proposed integrative analysis is composed of three steps: namely, (i) gene expression analysis of individual dataset; (ii) meta-analysis of multiple datasets; and (iii) feature selection and machine learning analysis. As a result, 21 gene expressions were identified through the integrative machine learning analysis which including seven supervised and one unsupervised methods. A functional analysis with GSEA (Gene Set Enrichment Analysis) was performed on the selected 21-gene expression set and showed significant enrichment in a nine-potential gene expression signature, namely PEG3, SPON1, BTD and RPLP2 (upregulated genes) and PRDX3, COPB2, LSM3, SLC5A3 and AS1B (downregulated genes)
Nano-cellulose biopolymer based nano-biofilm biomaterial using plant biomass: An innovative plant biomaterial dataset
No full textThe nano-cellulose derived nano-biofilm keeps a magnificent role in medical, biomedical, bioengineering and pharmaceutical industries. Plant biomaterial is naturally organic and biodegradable. This study has been highlighted as one of the strategy introducing biomass based nano-bioplastic (nanobiofilm) to solve dependency on petroleum and environment pollution because of non-degradable plastic. The data study was carried out to investigate the nano-biopolymer (nanocellulose) based nano-biofilm data from corn leaf biomass coming after bioprocess technology without chemicals. Corn leaf biomass was used to produce biodegradable nano-bioplastic for medical and biomedical and other industrial uses. Data on water absorption, odor, pH, cellulose content, shape and firmness, color coating and tensile strength test have been exhibited under standardization of ASTM (American standard for testing and materials). Moreover, the chemical elements of nanobiofilm like K+, CO3 −−, Cl−, Na+ showed standard data using the EN (166)
Prevalence rate of neck, shoulder and lower back pain in association with age, body mass index and gender among Malaysian office workers
No full textBackground: Malaysian office workers often experience Musculoskeletal Discomfort (MSD) which is typically related to the low back, shoulders, and neck. Objectives: The objective of this study was to examine the occurrence of lower back, shoulder, and neck pain among Malaysian office workers. Methods: 752 subjects (478 women and 274 men) were randomly selected from the Malaysian office workers population of 10,000 individuals. The participants were aged between 20-50 years and had at least one year of work experience. All participants completed the Cornell Musculoskeletal Discomfort Questionnaire (CMDQ). Instructions to complete the questinnaire were given to the participants under the researchers supervision in the morning before they started a day of work. The participants were then classified into four categories based on body mas index (BMI) (BMI:≤18.4, 18.5-24.99, 25-29.99, ≥30) and age (Age: 20-29, 30-39, 40-49, ≥50). Results: There was a significant association between pain severity in gender and right (p = 0.046) and left (p = 0.041) sides of the shoulders. There was also a significant association between BMI and severity of pain in the lower back area (p = 0.047). It was revealed that total pain score in the shoulders was significantly associated with age (p = 0.041). Conclusions: The results of this study demonstrated that a significant correlation existed between pain servity for gender in both right and left shoulder. These findings require further scientific investigation as do the identification of effective preventative stratgies
Catabolic activity and biofilm formation of foodborne Listeria monocytogenes strains
No full textListeria monocytogenes is a major foodborne pathogen causing increased morbidity worldwide. It forms resistant biofilm structures in food processing facilities after sanitization, consequently creating a public health concern. Many studies on the metabolism and transmission of L. monocytogenes has provided insights into its intracellular infection process, however there is limited understanding on the substrate utilization of the bacteria. Therefore, the main objective of this study was to investigate the carbon and nitrogen substrate catabolism and the biofilm forming potential of 3 Malaysian L. monocytogenes strains (LM41, LM92 and LM115) previously isolated from ready-to-eat foods. Biolog Phenotype Microarray (PM) system was used to study the catabolic activity of the foodborne strains in 190 carbon and 380 nitrogen sources. PM analysis showed that the carbon and nitrogen catabolic activity of L. monocytogenes strains were considerably limited and these strains utilised Tween 40 and Tween 80, which are commonly used for the sanitation in food and meat processing industries. Furthermore, all 3 strains showed strong biofilm forming potential in nutrient-rich and nutrient-limited media, irrespective of the serogroups. The data generated could be utilised to develop alternative measure to inhibit biofilm formation in L. monocytogenes in the food processing environment
Fabrication of un-doped and magnesium doped TiO2 films by aerosol assisted chemical vapor deposition for dye sensitized solar cells
No full textA Photoanode in dye sensitized solar cell is responsible for photoabsorption and conduction of the generated electrons for which TiO2 is a highly employed material due to its non-toxic nature and low cost. This study reports a convenient and facile method to prepare un-doped and magnesium (Mg) doped TiO2 thin films using Aerosol assisted Chemical Vapor deposition on Indium doped Tin oxide substrates. The as prepared films were subjected to morphological and structural characterizations as well as the optical absorption, band gap and surface area measurements of films. The studies indicated that Mg substituted Ti in the TiO2 lattice and formed new energy levels which decreased the band gap of the doped films. Moreover, increasing the concentration of Mg shifted the optical absorption of the films from ultra-violet region to the visible region. The IV measurements of the DSSCs fabricated using 2 mol% Mg doped TiO2 film, N719 dye, I−/I3− redox electrolyte and platinum sputtered on ITO counter electrode, revealed approximately twofold increase in overall efficiency of DSSCs as compared to undoped TiO2 based DSSC. The increase in Voc and Jsc, as well as the efficiency of 6.1%, is an indication that 2 mol% Mg doped TiO2 film is a potential candidate as a photoanode material in DSSC
A solid-state microwave method to disrupt biomass microstructure for natural product extraction
No full textThis paper introduces an innovative solid-state microwave disruption (SSMD) method for the extraction of bioactive materials from plants. It is an alternative method that avoids the use of solvents for plant biomass sample pretreatment unlike those in the conventional microwave methods. SSMD method is preferred since the heating and the vaporization of the intracellular moisture within the plant biomass is able to create sufficient pressure to disrupt the biomass microstructure. In this work, the superiority of the SSMD method was validated using the bioactive extraction from Orthosiphon stamineus (Java tea) leaves. First, the degree of disruption of SSMD method under the effects of microwave power and heating time were investigated at various up-scaled conditions based on the structural analysis of the treated sample, and the extraction yields of the bioactive compounds after soaking and elution with a suitable solvent at room conditions. The results show that the SSMD-elution method gave a better extraction yield (4.65 ± 0.08 mg/g), which is comparable to that of microwave-assisted extraction (4.45 ± 0.03 mg/g) and ultrasonic-assisted extraction (4.18 ± 0.02 mg/g). In addition, this method has great operational simplicity and flexibility in terms of operating parameters, types of solvent and solvent consumption
Low Lifetime Risk of Contralateral Breast Cancer in a Middle-Income Asian Country: Evidence to Guide Post-treatment Surveillance
No full textBackground: The rate of contralateral risk-reducing mastectomy (CRRM) is increasing in the West with controversial evidence of improved survival in early breast cancer patients. Although uptake of CRRM in Asia appears low, the trends may rise, and there is currently an urgent need to provide evidence for informed decision-making in clinical practice. This study aims to determine the risk of contralateral breast cancer (CBC) and its associated factors in an Asian setting. Method: A total of 2937 newly diagnosed patients with stage I and stage II breast cancer in University Malaya Medical Centre between Jan 1993 to Dec 2012 were included in the study. Multinomial logistic regression analysis allowing death to compete with CBC as a study outcome was used; patients with unilateral breast cancer who were alive were taken as reference. A stepwise backward regression analysis including age at diagnosis, ethnicity, family history of breast cancer, TNM stage, hormonal receptor status, HER2 status, chemotherapy, radiotherapy, and hormone therapy was conducted. Results: Fifty women developed CBC, over a median follow-up of 6 years. The 5- and 10-year cumulative risk of contralateral breast cancer was 1.0% (95% CI 0.6–1.4%) and 2.8% (95% CI 2.0–3.6%), respectively. Young age at diagnosis of first cancer, positive family history, and stage I disease were independent predictors of CBC. Discussion: The current study suggests that the risk of CBC is very low in a Southeast Asian setting. Any recommendations or practice of CRRM should be reviewed with caution and patients must be counseled appropriately
Size-dependent effect of cystine/citric acid-capped confeito-like gold nanoparticles on cellular uptake and photothermal cancer therapy
No full textPhysiochemical changes, including size, are known to affect gold nanoparticle cellular internalization and treatment efficacy. Here, we report the effect of four sizes of cystine/citric acid-coated confeito-like gold nanoparticles (confeito-AuNPs) (30, 60, 80 and 100 nm) on cellular uptake, intracellular localization and photothermal anticancer treatment efficiency in MDA-MB231 breast cancer cells. Cellular uptake is size dependent with the smallest size of confeito-AuNPs (30 nm) having the highest cellular internalization via clathrin- and caveolae-mediated endocytosis. However, the other three sizes (60, 80 and 100 nm) utilize clathrin-mediated endocytosis for cellular uptake. The intracellular localization of confeito-AuNPs is related to their endocytosis mechanism, where all sizes of confeito-AuNPs were localized highly in the lysosome and mitochondria, while confeito-AuNPs (30 nm) gave the highest localization in the endoplasmic reticulum. Similarly, a size-dependent trend was also observed in in vitro photothermal treatment experiments, with the smallest confeito-AuNPs (30 nm) giving the highest cell killing rate, whereas the largest size of confeito-AuNPs (100 nm) displayed the lowest photothermal efficacy. Its desirable physicochemical characteristics, biocompatible nature and better photothermal efficacy will form the basis for further development of multifunctional confeito-AuNP-based nanotherapeutic applications
In vitro and in silico studies of chalcone synthase variant 2 in Boesenbergia rotunda and its substrate specificity
No full textIn this study, transformation of BrCHS var 2 into B. rotunda cell suspension culture, followed by chalcone synthase enzymatic assay and HPLC analysis was conducted to investigate whether the substrate specificity for BrCHS var 2 is either cinnamoyl-CoA or p-coumaroyl-CoA. The HPLC profile showed an increase in the amount of pinocembrin chalcone when cinnamoyl-CoA and malonyl-CoA were added but not p-coumaroyl-CoA. Molecular docking was performed to explore the binding of cinnamoyl-CoA and p-coumaroyl-CoA to BrCHS var 2 receptor and the docking results showed that cinnamoyl-CoA formed numerous hydrogen bonds and more negative docked energy than p-coumaroyl-CoA. Cinnamoyl-CoA showed good interactions with Cys 164 to initiate the subsequent formation of pinocembrin chalcone, whereas the hydroxyl group of p-coumaroyl-CoA formed an unfavorable interaction with Gln 161 that caused steric hindrance to subsequent formation of naringenin chalcone. Docked conformation analysis results also showed that malonyl-CoA formed hydrogen bonding with Cys 164, His 303, and Asn 336 residues in BrCHS var 2. The results show that cinnamoyl-CoA is the preferred substrate for BrCHS var 2
Effect of Oxygen Pressure on Thermoelectric Properties of p-Type CuAlO2 Films Fabricated by Pulsed Laser Deposition
No full textWe focus on the growth of p-type CuAlO2 thin films and its thermoelectric properties. Thin films are deposited by pulsed laser deposition technique on single-crystal sapphire substrates varying the oxygen partial pressure. Thin film deposited at oxygen partial pressure of 200 mTorr presents bigger grains (about 10 μm in size) and shows Seebeck coefficient as high as 270 µV/K with a conductivity of about 0.8 S/cm so that its power factor is about 5.7 µW/mK2 at 800 K, twice than observed in the film deposited at 60 mTorr of oxygen