Displaying publications 461 - 480 of 1010 in total

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  1. Fulltext Biocompatibility assessment of fabricated melt-derived 45S5 bioactive glass on dental cells proliferation
    Mohd Zain N.S., Tajudin S.S., Mohd Noor S.N.F., Mohamad H.
    Journal of Biomedical and Clinical Sciences, 2016;1(1):26-32.
    MyJurnal
    Thisstudy aim tocharacterize melt-derivedbioactive glass and to determinethe bioactive glass (BG) suitability for dental usagethrough proliferative activity assessment of stem cells from human exfoliated deciduous teeth (SHED)when exposed to bioactive glass conditioned medium. Bioglass 45S5 in mole percentages (46.13% SiO2, 26.91% CaO, 24.35% Na2O and 2.60% P2O5)was synthesizedthrough melt-derived and characterized usingX-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR)to confirm and identify its properties.SHEDwere used to evaluate the biocompatibility of 45S5 by exposing the cells to various concentration of BG-conditioned medium (1-10 mg/ml) using alamarBlue assay. The BG produced has an amorphous structureas shown by XRD analysis. TheSi-O-Si bending, asymmetric Si-O stretching and asymmetricSi-O-Si stretchingbands were observed in the BG structure supporting the presenceof silicate network. For alamarBlue assay, SHED cultured in BG-conditioned medium showed high proliferation rate when subjected to minimal powder content in the DMEM cell culture medium.Hence, it can be concluded that SHED cultured in lower powder content of the BG-conditioned media showedhigh proliferative activity suggesting the potential of the BG for dental usage.
    Matched MeSH terms: Culture Media, Conditioned
  2. Fulltext Placental histopathological examination in foetal sepsis
    Haza Syakirin Mohamad Zin, Salmi Abdullah, Norazlah Bahari, Thandayathany, Vijayaletchumi, Hayati Abd Rahman, Nur Syahrina Rahim
    Borneo Journal of Medical Sciences, 2018;12(2):35-40.
    MyJurnal
    Intrauterine infection has emerged to be the main and frequent cause of premature delivery and foetal demise. Microorganisms gain entry into the amniotic cavity via ascending route, haematogenous dissemination, retrograde seeding from peritoneal cavity and accidental introduction during invasive procedures. This is a case of foetal loss in utero from a twin pregnancy due to intrauterine sepsis diagnosed through placenta examination. Both maternal and foetal evidences of inflammatory response were demonstrated in the placenta on histology. Microscopically, there were acute chorioamnionitis and villitis as well as abundant gram positive cocci in the foetal blood within placental villous capillaries. The presence of intravascular bacterial organism provides evidence for a conclusive diagnosis of intrauterine sepsis, particularly where the placenta or foetal blood microbiological cultures results are not available or equivocal. More attention should therefore be given when sampling, as pathological evidences of underlying foetal compromise or death could be provided by well-represented placental tissue samples.
    Matched MeSH terms: Blood Culture
  3. Guided evaluation and standardisation of mesenchymal stem cell culture conditions to generate conditioned medium favourable to cardiac c-kit cell growth
    Ng WH, Umar Fuaad MZ, Azmi SM, Leong YY, Yong YK, Ng AMH, et al.
    Cell Tissue Res, 2019 Feb;375(2):383-396.
    PMID: 30232595 DOI: 10.1007/s00441-018-2918-7
    Mesenchymal stem cells (MSCs) are known to secrete cardioprotective paracrine factors that can potentially activate endogenous cardiac c-kit cells (CCs). This study aims to optimise MSC growth conditions and medium formulation for generating the conditioned medium (CdM) to facilitate CC growth and expansion in vitro. The quality of MSC-CdM after optimisation of seeding density during MSC stabilisation and medium formulation used during MSC stimulation including glucose, ascorbic acid, serum and oxygen levels and the effects of treatment concentration and repeated CdM harvesting were assessed based on CC viability in vitro under growth factor- and serum-deprived condition. Our data showed that functional CdM can be produced from MSCs with a density of 20,000 cells/cm2, which were stimulated using high glucose (25 mM), ascorbic acid supplemented, serum-free medium under normoxic condition. The generated CdM, when applied to growth factor- and serum-deprived medium at 1:1 ratio, improved CC viability, migration and proliferation in vitro. Such an effect could further be augmented by generating CdM concentrates without compromising CC gene and protein expressions, while retaining its capability to undergo differentiation to form endothelial, smooth muscle and cardiomyocytes. Nevertheless, CdM could not be repeatedly harvested from the same MSC culture, as the protein content and its effect on CC viability deteriorated after the first harvest. In conclusion, this study provides a proof-of-concept strategy to standardise the production of CdM from MSCs based on rapid, stepwise assessment of CC viability, thus enabling production of CdM favourable to CC growth for in vitro or clinical applications.
    Matched MeSH terms: Culture Media, Conditioned/pharmacology*; Cell Culture Techniques/standards*
  4. Whistle blowing and research integrity: Potential remedy for research misconduct in Malaysian institutions of higher education
    Olesen AP, Amin L, Mahadi Z, Ibrahim M
    Account Res, 2019 01;26(1):17-32.
    PMID: 30489163 DOI: 10.1080/08989621.2018.1554444
    This study found that less than half of the respondents are willing to blow the whistle. The results reveal that a lack of protection with regard to the whistleblower's identity, the tedious investigative process, and the notion of avoiding confrontation, which is more apparent in Asian cultures as compared to the West, are among the reasons why individuals who witnessed misconduct chose to remain silent. Adhering to the Asian cultural upbringing where the young must respect the old, those of lower rank must obey those with higher authority, and subordinates do not question the actions of their superior, has become a norm even in the working environment. Therefore, emphasize the need for better protection for whistleblowers including using experienced individuals with a research ethics background to handle allegations from whistleblowers. In addition, established guidelines and procedures for whistleblowers with regard to voicing their allegations against colleagues engaged in research misconduct is still lacking or, to a certain extent, is still unknown to researchers. Thus, the concern indicates a need for institutions to create awareness among researchers regarding the existing platform for whistleblowers, or to develop a systematic and clear procedure which is reliable and independent to promote professionalism in academia.
    Matched MeSH terms: Culture
  5. Efficient differentiation of human ES and iPS cells into cardiomyocytes on biomaterials under xeno-free conditions
    Sung TC, Liu CH, Huang WL, Lee YC, Kumar SS, Chang Y, et al.
    Biomater Sci, 2019 Oct 28.
    PMID: 31656967 DOI: 10.1039/c9bm00817a
    Current xeno-free and chemically defined methods for the differentiation of hPSCs (human pluripotent stem cells) into cardiomyocytes are not efficient and are sometimes not reproducible. Therefore, it is necessary to develop reliable and efficient methods for the differentiation of hPSCs into cardiomyocytes for future use in cardiovascular research related to drug discovery, cardiotoxicity screening, and disease modeling. We evaluated two representative differentiation methods that were reported previously, and we further developed original, more efficient methods for the differentiation of hPSCs into cardiomyocytes under xeno-free, chemically defined conditions. The developed protocol successively differentiated hPSCs into cardiomyocytes, approximately 90-97% of which expressed the cardiac marker cTnT, with beating speeds and sarcomere lengths that were similar to those of a healthy adult human heart. The optimal cell culture biomaterials for the cardiac differentiation of hPSCs were also evaluated using extracellular matrix-mimetic material-coated dishes. Synthemax II-coated and Laminin-521-coated dishes were found to be the most effective and efficient biomaterials for the cardiac differentiation of hPSCs according to the observation of hPSC-derived cardiomyocytes with high survival ratios, high beating colony numbers, a similar beating frequency to that of a healthy adult human heart, high purity levels (high cTnT expression) and longer sarcomere lengths similar to those of a healthy adult human heart.
    Matched MeSH terms: Cell Culture Techniques
  6. Fulltext Senescent HUVECs-secreted exosomes trigger endothelial barrier dysfunction in young endothelial cells
    Wong PF, Tong KL, Jamal J, Khor ES, Lai SL, Mustafa MR
    EXCLI J, 2019;18:764-776.
    PMID: 31611757 DOI: 10.17179/excli2019-1505
    Accumulation of senescent endothelial cells can cause endothelium dysfunction which eventually leads to age-related vascular disorders. The senescent-associated secretory phenotype (SASP) cells secrete a plethora of soluble factors that negatively influence the surrounding tissue microenvironment. The present study sought to investigate the effects of exosomes, which are nano-sized extracellular vesicles known for intercellular communications secreted by SASP cells on young endothelial cells. Exosomes were isolated from the condition media of senescent human umbilical vein endothelial cells (HUVECs) and then confirmed by the detection of exosome specific CD63 and CD9 expressions, electron microscopy and acetylcholinesterase assay. The purified exosomes were used to treat young HUVECs. Exposure to exosomes repressed the expression of adherens junction proteins including vascular endothelial (VE)-cadherin and beta-catenin, decreased cell growth kinetics and impaired endothelial migration potential of young endothelial cells. These findings suggest that senescent HUVECs-secreted exosomes could disrupt barrier integrity that underpins endothelial barrier dysfunction in healthy young endothelial cells.
    Matched MeSH terms: Culture Media, Conditioned
  7. Diversity of fusarium species associated with post-harvest fruit rot disease of tomato
    Abu Bakar A, Nur Ain Izzati M, Umi Kalsom Y
    Sains Malaysiana, 2013;42:911-920.
    Fusarium species is one of the common pathogens of post-harvest disease to cause rot on tomato and other perishable vegetable fruits. The objectives of this study were to determine the diversity of Fusarium isolated species from post-harvest diseases of tomato fruit, to identify the causal organisms by using phenotype characteristics and to verify the pathogens of Fusarium fruit of tomato based on pathogenicity test. Carnation leaf-piece agar (CLA) and potato dextrose agar (PDA) media were used for phenotype-based identification of the Fusarium isolates with emphasis for characterizations of the shapes and sizes of the macroconidia and microconidia, colony features, growth rates, conidiogenous cells and chlamydospores. A total of 180 Fusarium isolates were obtained from 13 locations throughout Selangor. Fusarium solani was most abundantly isolated (34%) followed by F. semitectum (31%) and F. oxysporum (31%), F. subglutinans (3%) while the least was F. equiseti (1%). Twenty seven isolates were tested for pathogenicity test by injecting 1 mL of the conidial suspension onto healthy tomatoes. All the tested Fusarium isolates were pathogenic on tomato with different severity levels. The non-inoculated controls showed no symptoms of fruit rot. The most virulent was F. oxysporum isolate B711T with DSI 93.75%, while the least were isolates of F. solani (B647T) and F. oxysporum (B727T) with DSI 37.5%. Majority of the isolated Fusarium species can potentially produce mycotoxins as their secondary metabolites. The potential production of mycotoxins by pathogenic isolates of Fusarium species in contaminated tomato fruits could pose health hazards when consumed.
    Matched MeSH terms: Culture Media
  8. Microbial contamination level of water supply system at the faculty of dentistry, USIM, Malaysia
    Normaliza Ab. Malik, Rohazila Mohd Hanafiah, Wan Mohamad Nasi Wan Othman
    Sains Malaysiana, 2013;42:53-58.
    This study was to evaluate the microbial contamination level in direct water supply at the Polyclinic, Faculty of Dentistry, USIM, Malaysia. Water samples were collected randomly from water supplied via the cup filler outlet of 20 dental units and 20 side water taps at Level 16 and 17 of Polyclinic, Faculty of Dentistry, USIM. All the samples were placed and spread evenly on the surface of prepared agar media (the nutrient agar) using the spread technique. Each sample consists of 0.5 mL water. The microbial count was done using a magnifying glass and the total number of bacteria concentration was reported as colony forming unit in 1 mL of water (cfu/mL). In this study water from an aquarium was used as positive control with 220 cfu/mL, while the distilled water taken from the CSSD was used as negative control with no colony of microorganism. The study demonstrated that there were low contamination before the treatment that was beginning of the session in water supplied via the cup filler outlet and side water tap from the sink with 2 cfu/mL. However, two cup fillers water and one side water taps from Polyclinic level 17 showed a slightly higher bacterial colonies with 4 cfu/mL and 6 cfu/mL of microbes. At the end of the session, result showed that higher bacterial count from Polyclinic level 17 than Polyclinic level 16 with the highest reading of 40 cfu/mL. The findings were considered low and the water was safe for the dental procedures. The quality of water supplied at the Faculty of Dentistry, USIM was within the limits recommended by the American Dental Association, i.e. bacterial loads of not more than 200 cfu/mL for dental procedures.
    Matched MeSH terms: Culture Media
  9. Chondrogenesis of adipose-derived stem cells with chondrocytes in low serum towards clinical application
    Adila A Hamid, Satish Vaarman Jeyabalan, Aleza Omar, Nik Zattil Hanan Mohd Yasin, Wong TL, Liau LL, et al.
    Sains Malaysiana, 2018;47:2369-2379.
    Currently, fetal bovine serum (FBS) have been widely use in culture media to promote human cell proliferation. However,
    the usage of FBS for cell therapy in clinical application was associated with the risk of viral and prion transmission as
    well as immune rejection. To provide an option for this risk, this study was conducted to determine the effect of adipose
    derived stem cells (ADSCs) co-culture with chondrocyte in promoting cell proliferation and chondrogenesis toward
    FBS free condition. ADSCs co-cultured with chondrocyte at the ratio of 1:1, 2:1 and 1:2 were tested. Cell morphology
    changes, cell proliferation and gene expression level of stemness (Oct4, FGF-4, Nanog) and chondrogenic (Collagen
    Type II, ACP) were assessed. The results showed ADSCs in all co-culture groups changed morphology from fibroblastic
    spindle to polygonal shape which resembled chondrocytes. The morphological changes were accompanied with increased
    expression of chondrogenic genes; denoted chondrogenesis process. While maintaining expression of stemness genes
    indicated continuation of cell proliferation. From the three co-culture groups tested; ADSCs and chondrocytes (1:1 ratio)
    have been shown to exert better effects in promoting cell proliferation and chondrogenesis. In conclusion, ADSCs could
    replace FBS to grow sufficient number of chondrogenic cells to repair cartilage injury in the near future. Further in vivo
    study should be performed to test the effectiveness of this co-culture technique in cartilage injury repair.
    Matched MeSH terms: Culture Media
  10. Fulltext Phylogenetic relationships of Pseudo-nitzschia subpacifica (Bacillariophyceae) from the Mexican Pacific, and its production of domoic acid in culture
    Quijano-Scheggia SI, Olivos-Ortiz A, Garcia-Mendoza E, Sánchez-Bravo Y, Sosa-Avalos R, Salas Marias N, et al.
    PLoS One, 2020;15(4):e0231902.
    PMID: 32330168 DOI: 10.1371/journal.pone.0231902
    Pseudo-nitzschia is a cosmopolitan genus, some species of which can produce domoic acid (DA), a neurotoxin responsible for the Amnesic Shellfish Poisoning (ASP). In this study, we identified P. subpacifica for the first time in Todos Santos Bay and Manzanillo Bay, in the Mexican Pacific using SEM and molecular methods. Isolates from Todos Santos Bay were cultivated under conditions of phosphate sufficiency and deficiency at 16°C and 22°C to evaluate the production of DA. This toxin was detected in the particulate (DAp) and dissolved (DAd) fractions of the cultures during the exponential and stationary phases of growth of the cultures. The highest DA concentration was detected during the exponential phase grown in cells maintained in P-deficient medium at 16°C (1.14 ± 0.08 ng mL-1 DAd and 4.71 ± 1.11 × 10-5 ng cell-1 of DAp). In P-sufficient cultures DA was higher in cells maintained at 16°C (0.25 ± 0.05 ng mL-1 DAd and 9.41 ± 1.23 × 10-7 ng cell-1 of DAp) than in cells cultured at 22°C. Therefore, we confirm that P. subpacifica can produce DA, especially under P-limited conditions that could be associated with extraordinary oceanographic events such as the 2013-2016 "Blob" in the northeastern Pacific Ocean. This event altered local oceanographic conditions and possibly generated the presence of potential harmful species in areas with economic importance on the Mexican Pacific coast.
    Matched MeSH terms: Culture Techniques
  11. Fulltext A novel investigation of the influence of corporate governance on firms' credit ratings
    Alkhawaldeh AAK, Jaber JJ, Boughaci D, Ismail N
    PLoS One, 2021;16(5):e0250242.
    PMID: 33945537 DOI: 10.1371/journal.pone.0250242
    Corporate governance is the way of governing a firm in order to increase its accountability and to avoid any massive damage before it occurs. The aim of this paper is to investigate the impact of capital structure, firms' size, and competitive advantages of firms as control variables on credit ratings. We investigate the role of corporate governance in improving the firms' credit rating using a sample of Jordanian listed firms. We split firms into four categories according to WVB credit rating. We use both the binary logistic regression (LR) and the ordinal logistic regression (OLR) to model credit ratings in Jordanian environment. The empirical results show that the control variables are strong determinants of credit ratings. When we evaluate the relationship between the governance variables and credit ratings, we found interesting results. The board stockholders and board expertise are moderately significant. The board independence and role duality are weakly significant, while board size is insignificant.
    Matched MeSH terms: Organizational Culture
  12. Malaysian researchers talk about the influence of culture on research misconduct in higher learning institutions
    Olesen AP, Amin L, Mahadi Z
    Account Res, 2017;24(8):469-482.
    PMID: 29087734 DOI: 10.1080/08989621.2017.1399358
    Based on a previous survey by the Office of Research Integrity (ORI) in the USA, a considerable number of foreign research scientists have been found guilty of research misconduct. However, it remains unclear as to whether or not cultural factors really contribute to research misconduct. This study is based on a series of interviews with Malaysian researchers from the local universities regarding their own professional experiences involving working with researchers or research students from different countries or of different nationalities. Most of the researchers interviewed agreed that cultures do shape individual character, which influences the way that such individuals conduct research, their decision-making, and their style of academic writing. Our findings also showed that working culture within the institution also influences research practices, as well as faculty mentorship of the younger generation of researchers. Given the fact such misconduct might be due to a lack of understanding of research or working cultures or practices within the institution, the impact on the scientific community and on society could be destructive. Therefore, it is suggested that the institution has an important role to play in orienting foreign researchers through training, mentoring, and discussion with regard to the "does" and "don'ts" related to research, and to provide them with an awareness of the importance of ethics when it comes to conducting research.
    Matched MeSH terms: Organizational Culture
  13. Fulltext Quintuplex PCR to detect antibiotic resistance genes in Streptococcus pneumoniae
    Navindra Kumari Palanisamy, Parasakthi Navaratnam, Shamala Devi Sekaran
    Journal of Clinical and Health Sciences, 2016;1(2):22-28.
    MyJurnal
    Introduction: Streptococcus pneumoniae is an important bacterial pathogen, causing respiratory infection. Penicillin resistance in S. pneumoniae is associated with alterations in the penicillin binding proteins, while resistance to macrolides is conferred either by the modification of the ribosomal target site or efflux mechanism. This study aimed to characterize S. pneumoniae and its antibiotic resistance genes using 2 sets of multiplex PCRs. Methods: A quintuplex and triplex PCR was used to characterize the pbp1A, ermB, gyrA, ply, and the mefE genes. Fifty-eight penicillin sensitive strains (PSSP), 36 penicillin intermediate strains (PISP) and 26 penicillin resistance strains (PRSP) were used. Results: Alteration in pbp1A was only observed in PISP and PRSP strains, while PCR amplification of the ermB or mefE was observed only in strains with reduced susceptibility to erythromycin. The assay was found to be sensitive as simulated blood cultures showed the lowest level of detection to be 10cfu. Conclusions: As predicted, the assay was able to differentiate penicillin susceptible from the non-susceptible strains based on the detection of the pbp1A gene, which correlated with the MIC value of the strains.
    Matched MeSH terms: Blood Culture
  14. Fulltext Lumbar puncture refusal in febrile convulsion
    Ling SG, Boey CC
    Singapore Med J, 2000 Oct;41(10):485-8.
    PMID: 11281439
    A descriptive study was carried out on patients admitted for febrile convulsion over a two-year period to determine rate of lumbar puncture (LP) refusal, factors associated with LP refusal and outcome of such patients. From 77 patients indicated and requested for LP, 19 (25%) patients refused the procedure. Refusal of LP was significantly more common among the Malay ethnic group (p = 0.01) but not significantly associated with age,gender or whether the patient was admitted for a first or recurrent febrile convulsion. Half of the patients who refused LP had to be started empirically on antibiotics for meningitis. Patients who refused LP were also 8.5 times more likely to discharge themselves "at own risk" (AOR), compared to other patients with febrile convulsion (p = 0.004). In conclusion, LP refusal is a common problem in the local setting and is a hindrance to the proper management of patients with fever and seizure. Appropriate measures must be carried out to educate the public, particularly those from the Malay ethnic group on the safety and usefulness of the procedure. Reasons for patients discharging AOR following LP refusal also need to be addressed and problems rectified.
    Matched MeSH terms: Culture
  15. Fulltext A modeling study by response surface methodology and artificial neural network on culture parameters optimization for thermostable lipase production from a newly isolated thermophilic Geobacillus sp. strain ARM
    Ebrahimpour A, Abd Rahman RN, Ean Ch'ng DH, Basri M, Salleh AB
    BMC Biotechnol, 2008 Dec 23;8:96.
    PMID: 19105837 DOI: 10.1186/1472-6750-8-96
    BACKGROUND: Thermostable bacterial lipases occupy a place of prominence among biocatalysts owing to their novel, multifold applications and resistance to high temperature and other operational conditions. The capability of lipases to catalyze a variety of novel reactions in both aqueous and nonaqueous media presents a fascinating field for research, creating interest to isolate novel lipase producers and optimize lipase production. The most important stages in a biological process are modeling and optimization to improve a system and increase the efficiency of the process without increasing the cost.

    RESULTS: Different production media were tested for lipase production by a newly isolated thermophilic Geobacillus sp. strain ARM (DSM 21496 = NCIMB 41583). The maximum production was obtained in the presence of peptone and yeast extract as organic nitrogen sources, olive oil as carbon source and lipase production inducer, sodium and calcium as metal ions, and gum arabic as emulsifier and lipase production inducer. The best models for optimization of culture parameters were achieved by multilayer full feedforward incremental back propagation network and modified response surface model using backward elimination, where the optimum condition was: growth temperature (52.3 degrees C), medium volume (50 ml), inoculum size (1%), agitation rate (static condition), incubation period (24 h) and initial pH (5.8). The experimental lipase activity was 0.47 Uml(-1) at optimum condition (4.7-fold increase), which compared well to the maximum predicted values by ANN (0.47 Uml(-1)) and RSM (0.476 Uml(-1)), whereas R2 and AAD were determined as 0.989 and 0.059% for ANN, and 0.95 and 0.078% for RSM respectively.

    CONCLUSION: Lipase production is the result of a synergistic combination of effective parameters interactions. These parameters are in equilibrium and the change of one parameter can be compensated by changes of other parameters to give the same results. Though both RSM and ANN models provided good quality predictions in this study, yet the ANN showed a clear superiority over RSM for both data fitting and estimation capabilities. On the other hand, ANN has the disadvantage of requiring large amounts of training data in comparison with RSM. This problem was solved by using statistical experimental design, to reduce the number of experiments.

    Matched MeSH terms: Culture Media
  16. Modeling nasopharyngeal carcinoma in three dimensions
    Siva Sankar P, Che Mat MF, Muniandy K, Xiang BLS, Ling PS, Hoe SLL, et al.
    Oncol Lett, 2017 Apr;13(4):2034-2044.
    PMID: 28454359 DOI: 10.3892/ol.2017.5697
    Nasopharyngeal carcinoma (NPC) is a type of cancer endemic in Asia, including Malaysia, Southern China, Hong Kong and Taiwan. Treatment resistance, particularly in recurring cases, remains a challenge. Thus, studies to develop novel therapeutic agents are important. Potential therapeutic compounds may be effectively examined using two-dimensional (2D) cell culture models, three-dimensional (3D) spheroid models or in vivo animal models. The majority of drug assessments for cancers, including for NPC, are currently performed with 2D cell culture models. This model offers economical and high-throughput screening advantages. However, 2D cell culture models cannot recapitulate the architecture and the microenvironment of a tumor. In vivo models may recapitulate certain architectural and microenvironmental conditions of a tumor, however, these are not feasible for the screening of large numbers of compounds. By contrast, 3D spheroid models may be able to recapitulate a physiological microenvironment not observed in 2D cell culture models, in addition to avoiding the impediments of in vivo animal models. Thus, the 3D spheroid model offers a more representative model for the study of NPC growth, invasion and drug response, which may be cost-effective without forgoing quality.
    Matched MeSH terms: Cell Culture Techniques
  17. Fulltext Protein profiling and histone deacetylation activities in somaclonal variants of oil palm (Elaeis guineensis Jacq.)
    Yaacob JS, Loh HS, Mat Taha R
    ScientificWorldJournal, 2013;2013:613635.
    PMID: 23844406 DOI: 10.1155/2013/613635
    Mantled fruits as a result of somaclonal variation are often observed from the oil palm plantlets regenerated via tissue culture. The mantling of fruits with finger-like and thick outer coating phenotypes significantly reduces the seed size and oil content, posing a threat to oil palm planters, and may jeopardize the economic growth of countries that depend particularly on oil palm plantation. The molecular aspects of the occurrence of somaclonal variations are yet to be known, possibly due to gene repression such as DNA methylation, histone methylation and histone deacetylation. Histone deacetylases (HDACs), involved in eukaryotic gene regulation by catalyzing the acetyl groups are removal from lysine residues on histone, hence transcriptionally repress gene expression. This paper described the total protein polymorphism profiles of somaclonal variants of oil palm and the effects of histone deacetylation on this phenomenon. Parallel to the different phenotypes, the protein polymorphism profiles of the mantled samples (leaves, fruits, and florets) and the phenotypically normal samples were proven to be different. Higher HDAC activity was found in mantled leaf samples than in the phenotypically normal leaf samples, leading to a preliminary conclusion that histone deacetylation suppressed gene expression and contributed to the development of somaclonal variants.
    Matched MeSH terms: Tissue Culture Techniques
  18. Decoding stakeholder priorities of safety culture preferences in the oil and gas industry
    Rahim H, Dapari R, Che Dom N, Mohd Noor MI
    Sci Rep, 2024 Sep 05;14(1):20735.
    PMID: 39237550 DOI: 10.1038/s41598-024-71294-6
    Safety culture is a critical determinant of organisational performance, particularly in high-risk industries especially in oil and gas. Understanding stakeholder preferences is essential for developing effective strategies that enhance safety culture. This study utilised the Analytic Hierarchy Process (AHP) to prioritise stakeholder preferences, identifying key elements of safety culture in Malaysia's oil and gas sector. This study employed a structured methodology to evaluate safety culture within the oil and gas industry, focusing on 18 sub-elements across three key domains: psychological, behavioural, and situational factors. A diverse sample of industry experts was recruited using purposeful and snowball sampling to ensure a comprehensive representation of stakeholder views. The AHP framework was applied to analyse the data, utilizing structured questionnaires and multicriteria decision-making techniques to prioritize the identified safety culture elements. The AHP analysis identified distinct priorities among different professional groups within the oil and gas sector. Safety and Health Practitioners emphasized practical elements such as safety rules and management commitment, while academicians prioritized knowledge and training. Management personnel highlighted the importance of safety ownership and communication, whereas policymakers focused on broader, policy-oriented aspects. The findings suggest that safety culture improvement initiatives should be tailored to address the specific needs and priorities of each professional group. A nuanced understanding of stakeholder preferences is crucial for developing comprehensive strategies that integrate observable behaviours, situational conditions, and psychological factors, ultimately fostering a robust safety culture in the oil and gas industry.
    Matched MeSH terms: Organizational Culture
  19. Growth medium with low serum and transforming growth factor beta 3 promotes better chondrogenesis of bone marrow-derived stem cells in vitro and in vivo
    Alfaqeh HH, Hui CK, Saim AB, Idrus RB
    Saudi Med J, 2011 Jun;32(6):640-1.
    PMID: 21666950
    Matched MeSH terms: Culture Media
  20. Some morphological and anatomical studies of leaves and flowers of Murraya paniculata (Jack) Linn. in vivo and in vitro
    Taha RM, Haron NW
    Pak J Biol Sci, 2008 Apr 01;11(7):1021-6.
    PMID: 18810972
    In the present study, various explants of Murraya paniculata (Jack) Linn., such as cotyledons, shoots and young stems were cultured on MS medium supplemented with various concentrations of Benzyl Amino Purine (BAP) under 25 +/- 1 degree C with 16 h light and 8 h dark and also 8 h light and 16 h dark to obtain complete plant regeneration. In vitro flowering was observed from shoot explants cultured on MS supplemented with 0.5-2.0 mg L(-1) Naphthalene Acetic Acid (NAA) and also on MS basal medium under similar conditions. The leaves and flowers obtained from both in vivo and in vitro conditions were examined and compared. Morphological studies such as leaf clearing, epidermal peeling were studied using light and scanning electron microscope. Macromorphological studies of the flowers produced from in vivo and in vitro conditions were also examined. Morphologically, there were no differences between in vivo and in vitro flowers except the flowers produced from tissue culture systems were smaller in size with protruding stigmas. Differences were also found in the number of layers of palisade cells and the presence or absence of epicuticle layer of the leaves. Leaves produced from tissue culture system were smaller in size with membranous texture. Stomata were present only on the abaxial surfaces of both in vivo and in vitro leaves but the stomata were raised above the epidermis in the latter.
    Matched MeSH terms: Culture Media/pharmacology; Culture Media/chemistry; Tissue Culture Techniques
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