Displaying publications 1 - 20 of 998 in total

Abstract:
Sort:
  1. Xi Loh EY, Fauzi MB, Ng MH, Ng PY, Ng SF, Ariffin H, et al.
    ACS Appl Mater Interfaces, 2018 Nov 21;10(46):39532-39543.
    PMID: 30372014 DOI: 10.1021/acsami.8b16645
    The evaluation of the interaction of cells with biomaterials is fundamental to establish the suitability of the biomaterial for a specific application. In this study, the properties of bacterial nanocellulose/acrylic acid (BNC/AA) hydrogels fabricated with varying BNC to AA ratios and electron-beam irradiation doses were determined. The manner these hydrogel properties influence the behavior of human dermal fibroblasts (HDFs) at the cellular and molecular levels was also investigated, relating it to its application both as a cell carrier and wound dressing material. Swelling, hardness, adhesive force (wet), porosity, and hydrophilicity (dry) of the hydrogels were dependent on the degree of cross-linking and the amount of AA incorporated in the hydrogels. However, water vapor transmission rate, pore size, hydrophilicity (semidry), and topography were similar between all formulations, leading to a similar cell attachment and proliferation profile. At the cellular level, the hydrogel demonstrated rapid cell adhesion, maintained HDFs viability and morphology, restricted cellular migration, and facilitated fast transfer of cells. At the molecular level, the hydrogel affected nine wound-healing genes (IL6, IL10, MMP2, CTSK, FGF7, GM-CSF, TGFB1, COX2, and F3). The findings indicate that the BNC/AA hydrogel is a potential biomaterial that can be employed as a wound-dressing material to incorporate HDFs for the acceleration of wound healing.
    Matched MeSH terms: Culture Media
  2. Akbar N, Siddiqui R, Iqbal M, Sagathevan K, Kim KS, Habib F, et al.
    ACS Omega, 2021 May 11;6(18):12261-12273.
    PMID: 34056379 DOI: 10.1021/acsomega.1c01137
    Among several animals, Rattus rattus (rat) lives in polluted environments and feeds on organic waste/small invertebrates, suggesting the presence of inherent mechanisms to thwart infections. In this study, we isolated gut bacteria of rats for their antibacterial activities. Using antibacterial assays, the findings showed that the conditioned media from selected bacteria exhibited bactericidal activities against Gram-negative (Escherichia coli K1, Klebsiella pneumoniae, Pseudomonas aeruginosa, Serratia marcescens, and Salmonella enterica) and Gram-positive (Bacillus cereus, methicillin-resistant Staphylococcus aureus, and Streptococcus pyogenes) pathogenic bacteria. The conditioned media retained their antibacterial properties upon heat treatment at boiling temperature for 10 min. Using MTT assays, the conditioned media showed minimal cytotoxic effects against human keratinocyte cells. Active conditioned media were subjected to tandem mass spectrometry, and the results showed that conditioned media from Bacillus subtilis produced a large repertoire of surfactin and iturin A (lipopeptides) molecules. To our knowledge, this is the first report of isolation of lipopeptides from bacteria isolated from the rat gut. In short, these findings are important and provide a platform to develop effective antibacterial drugs.
    Matched MeSH terms: Culture Media, Conditioned
  3. Muntari B, Amid A, Mel M, Jami MS, Salleh HM
    AMB Express, 2012;2:12.
    PMID: 22336426 DOI: 10.1186/2191-0855-2-12
    Bromelain, a cysteine protease with various therapeutic and industrial applications, was expressed in Escherichia coli, BL21-AI clone, under different cultivation conditions (post-induction temperature, L-arabinose concentration and post-induction period). The optimized conditions by response surface methodology using face centered central composite design were 0.2% (w/v) L-arabinose, 8 hr and 25°C. The analysis of variance coupled with larger value of R2 (0.989) showed that the quadratic model used for the prediction was highly significant (p < 0.05). Under the optimized conditions, the model produced bromelain activity of 9.2 U/mg while validation experiments gave bromelain activity of 9.6 ± 0.02 U/mg at 0.15% (w/v) L-arabinose, 8 hr and 27°C. This study had innovatively developed cultivation conditions for better production of recombinant bromelain in shake flask culture.
    Matched MeSH terms: Batch Cell Culture Techniques
  4. 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. 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
  6. Venil CK, Zakaria ZA, Ahmad WA
    Acta Biochim. Pol., 2015;62(2):185-90.
    PMID: 25979288 DOI: 10.18388/abp.2014_870
    Flexirubins are the unique type of bacterial pigments produced by the bacteria from the genus Chryseobacterium, which are used in the treatment of chronic skin disease, eczema etc. and may serve as a chemotaxonomic marker. Chryseobacterium artocarpi CECT 8497, an yellowish-orange pigment producing strain was investigated for maximum production of pigment by optimizing medium composition employing response surface methodology (RSM). Culture conditions affecting pigment production were optimized statistically in shake flask experiments. Lactose, l-tryptophan and KH2PO4 were the most significant variables affecting pigment production. Box Behnken design (BBD) and RSM analysis were adopted to investigate the interactions between variables and determine the optimal values for maximum pigment production. Evaluation of the experimental results signified that the optimum conditions for maximum production of pigment (521.64 mg/L) in 50 L bioreactor were lactose 11.25 g/L, l-tryptophan 6 g/L and KH2PO4 650 ppm. Production under optimized conditions increased to 7.23 fold comparing to its production prior to optimization. Results of this study showed that statistical optimization of medium composition and their interaction effects enable short listing of the significant factors influencing maximum pigment production from Chryseobacterium artocarpi CECT 8497. In addition, this is the first report optimizing the process parameters for flexirubin type pigment production from Chryseobacterium artocarpi CECT 8497.
    Matched MeSH terms: Culture Media/metabolism; Culture Media/chemistry*; Batch Cell Culture Techniques
  7. Sivakumar P, Law YS, Ho CL, Harikrishna JA
    Acta. Biol. Hung., 2010 Sep;61(3):313-21.
    PMID: 20724277 DOI: 10.1556/ABiol.61.2010.3.7
    An efficient in vitro plant regeneration system was established for elite, recalcitrant Malaysian indica rice, Oryza sativa L. CV. MR 219 using mature seeds as explant on Murashige and Skoog and Chu N6 media containing 2,4-dichlorophenoxy acetic acid and kinetin either alone or in different combinations. L-proline, casein hydrolysate and L-glutamine were added to callus induction media for enhancement of embryogenic callus induction. The highest frequency of friable callus induction (84%) was observed in N6 medium containing 2.5 mg l(-1) 2,4-dichlorophenoxy acetic acid, 0.2 mg l(-1) kinetin, 2.5 mg l(-1) L-proline, 300 mg l(-1) casein hydrolysate, 20 mg l(-1) L-glutamine and 30 g l(-1) sucrose under culture in continuous lighting conditions. The maximum regeneration frequency (71%) was observed, when 30-day-old N6 friable calli were cultured on MS medium supplemented with 3 mg l(-1) 6-benzyl aminopurine, 1 mg l(-1) naphthalene acetic acid, 2.5 mg l(-1) L-proline, 300 mg l(-1) casein hydrolysate and 3% maltose. Developed shoots were rooted in half strength MS medium supplemented with 2% sucrose and were successfully transplanted to soil with 95% survival. This protocol may be used for other recalcitrant indica rice genotypes and to transfer desirable genes in to Malaysian indica rice cultivar MR219 for crop improvement.
    Matched MeSH terms: Culture Media/chemistry; Culture Techniques
  8. Petre-Quadens O, Hussain H, Balaratnan C
    Acta Neurol Belg, 1975 Mar;75(2):85-92.
    PMID: 168717
    The Temiars are a tribe of negroid pygmies of basically Proto-Malaysian affinities. Field-work in the Malaysian jungle provided some observations on the sleep-wakefulness cycle of two young Temiar adults. This cycle was monophasic circumstances permitting. Their rest-activity cycle at night was similar in the jungle and in the laboratory. Polygraphic total night-sleep recordings were made with both of them in the EEG laboratory in the Hospital Besar in Kuala Lumpur. The eye-movement frequencies of PS were compared with those from young adults of the West. Although the differences were not statistically significant, the Rem-densities of the Temiars were constantly at the low side. The significance of the results are being discussed.
    Matched MeSH terms: Cultural Characteristics*; Culture*
  9. Goh BS, Che Omar SN, Ubaidah MA, Saim L, Sulaiman S, Chua KH
    Acta Otolaryngol, 2017 Apr;137(4):432-441.
    PMID: 27900891 DOI: 10.1080/00016489.2016.1257151
    CONCLUSION: In conclusion, these result showed HADSCs could differentiate into chondrocytes-like cells, dependent on signaling induced by TGF-β3 and chondrocytes. This is a promising result and showed that HADSCs is a potential source for future microtia repair. The technique of co-culture is a positive way forward to assist the microtia tissue.

    OBJECTIVE: Reconstructive surgery for the repair of microtia still remains the greatest challenge among the surgeons. Its repair is associated with donor-site morbidity and the degree of infection is inevitable when using alloplastic prosthesis with uncertain long-term durability. Thus, human adipose derived stem cells (HADSCs) can be an alternative cell source for cartilage regeneration. This study aims to evaluate the chondrogenic potential of HADSCs cultured with transforming growth factor-beta (TGF-β) and interaction of auricular chondrocytes with HADSCs for new cartilage generation.

    METHODS: Multi-lineages differentiation features of HADSCs were monitored by Alcian Blue, Alizarin Red, and Oil Red O staining for chondrogenic, adipogenic, and osteogenic differentiation capacity, respectively. Further, HADSCs alone were culture in medium added with TGF-β3; and human auricular chondrocytes were interacted indirectly in the culture with and without TGF-βs for up to 21 days, respectively. Cell morphology and chondrogenesis were monitored by inverted microscope. For cell viability, Alamar Blue assay was used to measure the cell viability and the changes in gene expression of auricular chondrocyte markers were determined by real-time polymerase chain reaction analysis. For the induction of chondrogenic differentiation, HADSCs showed a feature of aggregation and formed a dense matrix of proteoglycans. Staining results from Alizirin Red and Oil Red O indicated the HADSCs also successfully differentiated into adipogenic and osteogenic lineages after 21 days.

    RESULTS: According to a previous study, HADSCs were strongly positive for the mesenchymal markers CD90, CD73, CD44, CD9, and histocompatibility antigen. The results showed HADSCs test groups (cultured with TGF-β3) displayed chondrocytes-like cells morphology with typical lacunae structure compared to the control group without TGF-β3 after 2 weeks. Additionally, the HADSCs test groups increased in cell viability; an increase in expression of chondrocytes-specific genes (collagen type II, aggrecan core protein, SOX 9 and elastin) compared to the control. This study found that human auricular chondrocytes cells and growth factor had a positive influence in inducing HADSCs chondrogenic effects, in terms of chondrogenic differentiate of feature, increase of cell viability, and up-regulated expression of chondrogenic genes.

    Matched MeSH terms: Primary Cell Culture
  10. Lee HY, Loong SK, Ya'cob Z, Low VL, Teoh BT, Ahmad-Nasrah SN, et al.
    Acta Trop, 2021 Jul;219:105923.
    PMID: 33878305 DOI: 10.1016/j.actatropica.2021.105923
    Although the microbiome of blood-feeding insects serves an integral role in host physiology, both beneficial and pathogenic, little is known of the microbial community of black flies. An investigation, therefore, was undertaken to identify culturable bacteria from one of Malaysia's most common black flies, Simulium tani Takaoka and Davies, using 16S rDNA sequencing, and then evaluate the isolates for antibiotic resistance and virulence genes. A total of 20 isolates representing 11 bacterial species in four genera were found. Five isolates showed β-hemolysis on Columbia agar, and virulence genes were found in three of these isolates. Some degree of resistance to six of the 12 tested antibiotics was found among the isolates. The baseline data from this study suggest rich opportunities for comparative studies exploring the diversity and roles of the microbiome of S. tani and other Southeast Asian black flies.
    Matched MeSH terms: Culture Techniques
  11. El Enshasy H, Malik K, Malek RA, Othman NZ, Elsayed EA, Wadaan M
    PMID: 26907552
    Human gastrointestinal microbiota (HGIM) incorporate a large number of microbes from different species. Anaerobic bacteria are the dominant organisms in this microbial consortium and play a crucial role in human health. In addition to their functional role as the main source of many essential metabolites for human health, they are considered as biotherapeutic agents in the regulation of different human metabolites. They are also important in the prevention and in the treatment of different physical and mental diseases. Bifidobacteria are the dominant anaerobic bacteria in HGIM and are widely used in the development of probiotic products for infants, children and adults. To develop bifidobacteria-based bioproducts, therefore, it is necessary to develop a large-scale biomass production platform based on a good understanding of the ideal medium and bioprocessing parameters for their growth and viability. In addition, high cell viability should be maintained during downstream processing and storage of probiotic cell powder or the final formulated product. In this work we review the latest information about the biology, therapeutic activities, cultivation and industrial production of bifidobacteria.
    Matched MeSH terms: Batch Cell Culture Techniques/methods*
  12. Haque N, Widera D, Abu Kasim NH
    Adv Exp Med Biol, 2019;1084:175-186.
    PMID: 30771186 DOI: 10.1007/5584_2018_299
    BACKGROUND: The response of stem cells to paracrine factors within the host's body plays an important role in the regeneration process after transplantation. The aim of this study was to determine the viability and paracrine factor profile of stem cells from human extracted deciduous teeth (SHED) pre-cultivated in media supplemented with either foetal bovine serum (FBS) or pooled human serum (pHS) in the presence of individual human sera (iHS).

    METHODS: SHED (n = 3) from passage 4 were expanded in FBS (FBS-SHED) or pHS (pHS-SHED) supplemented media until passage 7. During expansion, the proliferation of SHED was determined. Cells at passage 7 were further expanded in human serum from four individual donors (iHS) for 120 h followed by assessment of cell viability and profiling of the secreted paracrine factors.

    RESULTS: Proliferation of SHED was significantly higher (p 

    Matched MeSH terms: Cell Culture Techniques
  13. Haque N, Abu Kasim NH
    Adv Exp Med Biol, 2017 7 22;1083:29-44.
    PMID: 28730381 DOI: 10.1007/5584_2017_74
    In regenerative therapy, in vitro expansion of stem cells is critical to obtain a significantly higher number of cells for successful engraftment after transplantation. However, stem cells lose its regenerative potential and enter senescence during in vitro expansion. In this study, the influence of foetal bovine serum (FBS) and pooled human serum (pHS) on the proliferation, morphology and migration of stem cells from human extracted deciduous teeth (SHED) was compared. SHED (n = 3) was expanded in KnockOut DMEM supplemented with either pHS (pHS-SM) or FBS (FBS-SM). pHS was prepared using peripheral blood serum of six healthy male adults, aged between 21 and 35 years old. The number of live SHED was significantly higher, from passage 5 to 7, when cultured in pHS-SM compared to those cultured in FBS-SM (p 
    Matched MeSH terms: Cell Culture Techniques
  14. Ramasamy TS, Ong ALC, Cui W
    Adv Exp Med Biol, 2018 10 26;1077:41-66.
    PMID: 30357683 DOI: 10.1007/978-981-13-0947-2_4
    Generation of functional hepatocytes from human pluripotent stem cells (hPSCs) is a vital tool to produce large amounts of human hepatocytes, which hold a great promise for biomedical and regenerative medicine applications. Despite a tremendous progress in developing the differentiation protocols recapitulating the developmental signalling and stages, these resulting hepatocytes from hPSCs yet achieve maturation and functionality comparable to those primary hepatocytes. The absence of 3D milieu in the culture and differentiation of these hepatocytes may account for this, at least partly, thus developing an optimal 3D culture could be a step forward to achieve this aim. Hence, review focuses on current development of 3D culture systems for hepatic differentiation and maturation and the future perspectives of its application.
    Matched MeSH terms: Cell Culture Techniques/trends*
  15. Busra MF, Chowdhury SR, bin Ismail F, bin Saim A, Idrus RB
    Adv Skin Wound Care, 2016 Mar;29(3):120-9.
    PMID: 26866868 DOI: 10.1097/01.ASW.0000480556.78111.e4
    OBJECTIVE: When given in conjunction with surgery for treating cancer, radiation therapy may result in impaired wound healing, which, in turn, could cause skin ulcers. In this study, bilayer and monolayer autologous skin substitutes were used to treat an irradiated wound.

    MATERIALS AND METHODS: A single dose of 30 Gy of linear electron beam radiation was applied to the hind limb of nude mice before creating the skin lesion (area of 78.6 mm). Monolayer tissue-engineered skin substitutes (MTESSs) were prepared by entrapping cultured keratinocytes in fibrin matrix, and bilayer tissue-engineered skin substitutes (BTESSs) were prepared by entrapping keratinocytes and fibroblasts in separate layers. Bilayer tissue-engineered skin substitute and MTESS were implanted to the wound area. Gross appearance and wound area were analyzed to evaluate wound healing efficiency. Skin regeneration and morphological appearance were observed via histological and electron microscopy. Protein expressions of transforming growth factor β1 (TGF-β1), platelet-derived growth factor BB (PDGF-BB), and vascular endothelial growth factor (VEGF) in skin regeneration were evaluated by immunohistochemistry (IHC).

    RESULTS: Macroscopic observation revealed that at day 13, treatments with BTESS completely healed the irradiated wound, whereas wound sizes of 1.1 ± 0.05 and 6.8 ± 0.14 mm were measured in the MTESS-treated and untreated control groups, respectively. Hematoxylin-eosin (H&E) analysis showed formation of compact and organized epidermal and dermal layers in the BTESS-treated group, as compared with MTESS-treated and untreated control groups. Ultrastructural analysis indicates maturation of skin in BTESS-treated wound evidenced by formation of intermediate filament bundles in the dermal layer and low intercellular space in the epidermal layer. Expressions of TGF-β1, PDGF-BB, and VEGF were also higher in BTESS-treated wounds, compared with MTESS-treated wounds.

    CONCLUSIONS: These results indicate that BTESS is the preferred treatment for irradiated wound ulcers.

    Matched MeSH terms: Cell Culture Techniques
  16. Musa M, Nasir NF, Thirumulu KP
    PMID: 24653569
    Royal jelly is a nutritious substance produced by the young nurse bees and contains significant amounts of proteins which are important for cell growth and proliferation. The aim of this study was to evaluate the effect of royal jelly as an alternative to fetal bovine serum (FBS) in cell culture using cell proliferation assays and live cell imaging.
    Matched MeSH terms: Culture Media/chemistry*
  17. Lim L, Ng TP, Ong AP, Tan MP, Cenina AR, Gao Q, et al.
    Alzheimers Res Ther, 2018 01 22;10(1):6.
    PMID: 29370825 DOI: 10.1186/s13195-017-0333-z
    BACKGROUND: Cognitive screeners are imperative for early diagnosis of dementia. The Visual Cognitive Assessment Test (VCAT) is a language-neutral, visual-based test which has proven useful for a multilingual population in a single-center study. However, its performance utility is unknown in a wider and more diverse Southeast Asian cohort.

    METHODS: We recruited 164 healthy controls (HC) and 120 cognitively impaired (CI) subjects- 47 mild cognitive impairment (MCI) and 73 mild Alzheimer's disease (AD) dementia participants, from four countries between January 2015 and August 2016 to determine the usefulness of a single version of the VCAT, without translation or adaptation, in a multinational, multilingual population. The VCAT was administered along with established cognitive evaluation.

    RESULTS: The VCAT, without local translation or adaptation, was effective in discriminating between HC and CI subjects (MCI and mild AD dementia). Mean (SD) VCAT scores for HC and CI subjects were 22.48 (3.50) and 14.17 (5.05) respectively. Areas under the curve for Montreal Cognitive Assessment (0.916, 95% CI 0.884-0.948) and the VCAT (0.905, 95% CI 0.870-0.940) in discriminating between HCs and CIs were comparable. The multiple languages used to administer VCAT in four countries did not significantly influence test scores.

    CONCLUSIONS: The VCAT without the need for language translation or cultural adaptation showed satisfactory discriminative ability and was effective in a multinational, multilingual Southeast Asian population.

    Matched MeSH terms: Culture
  18. Kinzie JD
    Am J Psychother, 1972 Apr;26(2):220-31.
    PMID: 5024276
    Matched MeSH terms: Cross-Cultural Comparison; Culture*
  19. Omar Farouk FN, Stott D, Vlad M
    Anim Sci J, 2011 Jun;82(3):420-7.
    PMID: 21615835 DOI: 10.1111/j.1740-0929.2010.00869.x
    This study was conducted to examine the potential for implantation and sustainable fetal development of mouse embryos cultured from the pronuclear to blastocyst stage. Pronuclear embryos from ICR mice (Harlan Sprague-Dawley) were cultured in Sydney IVF sequential media (Cook) to the blastocyst stage in medium only or co-cultured with autologous cumulus cells. We also experimented with co-culture in 100 µL drops. Drop co-culture produced blastocyst formation rates with a mean of 47.0%, which was significantly higher (P < 0.05) compared to embryos cultured in identical culture conditions except without cumulus cells at 27.3%. Blastocysts obtained in vitro in Cook medium only and co-cultured in Cook medium with cumulus cells were transferred to pseudopregnant females of ICR strain. The day of blastocyst transfer into surrogate females was designated as post-transfer of blastocyst day 1 (PT 1). The implantation and fetal development was compared to embryo transfer of in vivo derived blastocysts, which served as controls. There were no statistical differences for implantation and fetal development rates for blastocysts cultured in vitro in either Cook medium only or co-culture in Cook medium with cumulus cells compared to in vivo-derived blastocysts. The advantage of the co-culture system is in generating more blastocysts available for transfer.
    Matched MeSH terms: Culture Media
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links