Displaying publications 21 - 40 of 186 in total

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  1. Samie N, Muniandy S, Kanthimathi MS, Haerian BS, Azudin RE
    Sci Rep, 2016 Apr 13;6:24172.
    PMID: 27072064 DOI: 10.1038/srep24172
    The current study evaluates the cytotoxic mechanism of a novel piperazine derivate designated as PCC against human liver cancer cells. In this context, human liver cancer cell lines, SNU-475 and 243, human monocyte/macrophage cell line, CRL-9855, and human B lymphocyte cell line, CCL-156, were used to determine the IC50 of PCC using the standard MTT assay. PCC displayed a strong suppressive effect on SNU-475 and SNU-423 cells with an IC50 value of 6.98 ± 0.11 μg/ml and 7.76 ± 0.45 μg/ml respectively, after 24 h of treatment. Significant dipping in the mitochondrial membrane potential and elevation in the released of cytochrome c from the mitochondria indicated the induction of the intrinsic apoptosis pathway by PCC. Activation of this pathway was further evidenced by significant activation of caspase 3/7 and 9. PCC was also shown to activate the extrinsic pathways of apoptosis via activation of caspase-8 which is linked to the suppression of NF-ƙB translocation to the nucleus. Cell cycle arrest in the G1 phase was confirmed by flow cytometry and up-regulation of glutathione reductase expression was quantified by qPCR. This study suggests that PCC is a simultaneous inducer of intrinsic and extrinsic pathways of apoptosis in liver cancer cell lines.
    Matched MeSH terms: Flow Cytometry
  2. Ku Nurul Aqmar Ku Bahaudin, Ahmad Bazli Ramzi, Syarul Nataqain Baharum, Suriana Sabri, Adam Leow Thean Chor, Tewin Tencomnao
    Sains Malaysiana, 2018;47:3077-3084.
    Flavonoid is an industrially-important compound due to its high pharmaceutical and cosmeceutical values. However,
    conventional methods in extracting and synthesizing flavonoids are costly, laborious and not sustainable due to small
    amount of natural flavonoids, large amounts of chemicals and space used. Biotechnological production of flavonoids
    represents a viable and sustainable route especially through the use of metabolic engineering strategies in microbial
    production hosts. In this review, we will highlight recent strategies for the improving the production of flavonoids
    using synthetic biology approaches in particular the innovative strategies of genetically-encoded biosensors for in
    vivo metabolite analysis and high-throughput screening methods using fluorescence-activated cell sorting (FACS).
    Implementation of transcription factor based-biosensor for microbial flavonoid production and integration of systems
    and synthetic biology approaches for natural product development will also be discussed.
    Matched MeSH terms: Flow Cytometry
  3. Swathirajan CR, Nandagopal P, Vignesh R, Srikrishnan AK, Goyal R, Qureshi H, et al.
    Pathog Dis, 2019 06 01;77(4).
    PMID: 31505637 DOI: 10.1093/femspd/ftz044
    HIV-1 vaccine functioning relies on successful induction of broadly neutralizing antibodies (bNAbs). CXCR3- circulatory T-follicular helper (cTfh) cells are necessary for inducing B-cells for generating bNAbs. Recent studies have suggested that CXCR3+ Tfh cells might also influence bNAb production. Plasma samples from 34 ART-Naïve HIV-1 infected individuals [long-term nonprogressors (LTNP)-19; Progressors-13] were tested against a heterologous virus panel (n = 11) from subtypes A, B, C, G, AC, BC and AE. Frequencies of CXCR3+ and CXCR3- cTfh-like cells in peripheral circulation were studied using flow cytometry. LTNP showed significantly lower CXCR3+ and higher CXCR3- cTfh-like cell frequencies, while neutralization breadth was observed to be broader in progressors. A positive correlation was observed between bNAb breadth and potency with CXCR3+PD-1+ cTfh-like cells in LTNP. Based on neutralization breadth, 9 HIV-1 infected individuals were classified as 'top neutralizers' and 23 as 'low neutralizers' and they did not show any correlations with CXCR3+ and CXCR3- cTfh-like cells. These preliminary data suggest that CXCR3+ similar to CXCR3- might possess significant functional properties for driving B-cells to produce bNAbs. Hence, an HIV vaccine which is capable of optimal induction of CXCR3+ cTfh cells at germinal centers might confer superior protection against HIV.
    Matched MeSH terms: Flow Cytometry
  4. Mohd Ashari NS, Mohamed Sanusi SNF, Mohd Yasin MA, Che Hussin CM, Wong KK, Shafei MN
    Malays J Pathol, 2019 Aug;41(2):169-176.
    PMID: 31427552
    INTRODUCTION: Regulatory T cell (Treg) is a subtype of T lymphocyte that plays a crucial role in establishing immunologic self-tolerance and maintaining immune homeostasis. In this study, we set out to investigate the percentage and absolute count of Tregs in major depressive disorder (MDD) patients and their correlation with disease severity.

    MATERIALS & METHODS: This is a case-control study consisting of 47 MDD patients and 47 healthy controls. MDD patients were treated with antidepressant drugs according to their physician's choice. The severity of MDD was assessed using Beck Depression Inventory (BDI) and Montgomery-Asberg Depression Rating Scale (MADRS) at the time of recruitment. Healthy controls completed the Depression Anxiety Scoring System (DASS21) questionnaire to ensure they were in good mental health without history of MDD. The percentage and absolute count of CD4+ CD25+ Tregs and CD4+ CD25+ FOXP3+ Tregs were identified by multiparameter flow cytometry.

    RESULTS: The percentage and absolute count of CD4+ CD25+ Treg cells were significantly higher in MDD patients than in healthy controls (P<0.001, in both cases). Likewise, the percentage and absolute count of CD4+ CD25+ FOXP3+ Treg cells were also significantly higher in MDD patients compared to healthy controls (P=0.003 and P=0.002, respectively). However, there was no significant correlation between the percentage and absolute count of CD4+ CD25+ Treg and CD4+ CD25+ FOXP3+ Treg cells with BDI or MADRS score.

    CONCLUSIONS: Our results suggest that antidepressant treatments contributed to an upregulation of Tregs in MDD patients.

    Matched MeSH terms: Flow Cytometry
  5. Omar Zaki SS, Katas H, Hamid ZA
    Food Chem Toxicol, 2015 Nov;85:31-44.
    PMID: 26051352 DOI: 10.1016/j.fct.2015.05.017
    Chitosan nanoparticles (CSNPs) have potential applications in stem cell research. In this study, ex vivo cytotoxicity of CSNPs on mouse bone marrow-derived (MBMCs) hematopoietic stem and progenitor cells (HSPCs) was determined. MBMCs were exposed to CSNPs of different particle sizes at various concentrations for up to 72 h. Cytotoxicity effect of CSNPs on MBMCs was determined using MTT, Live/Dead Viability/Cytotoxicity assays and flow cytometry analysis of surface antigens on HSCs (Sca-1(+)), myeloid-committed progenitors (CD11b(+), Gr-1(+)), and lymphoid-committed progenitors (CD45(+), CD3e(+)). At 24 h incubation, MBMCs' viability was not affected by CSNPs. At 48 and 72 h, significant reduction was detected at higher CSNPs concentrations. Small CSNPs (200 nm) significantly reduced MBMCs' viability while medium-sized particle (∼400 nm) selectively promoted MBMCs growth. Surface antigen assessment demonstrated lineage-dependent effect. Significant decrease in Sca-1(+) cells percentage was observed for medium-sized particle at the lowest CSNPs concentration. Meanwhile, reduction of CD11b(+) and Gr-1(+) cells percentage was detected at high and intermediate concentrations of medium-sized and large CSNPs. Percentage of CD45(+) and CD3e(+) cells along with ROS levels were not significantly affected by CSNPs. In conclusion, medium-sized and large CSNPs were relatively non-toxic at lower concentrations. However, further investigations are necessary for therapeutic applications.
    Matched MeSH terms: Flow Cytometry
  6. Takenaka S, Weschke W, Brückner B, Murata M, Endo TR
    Front Plant Sci, 2019;10:548.
    PMID: 31114602 DOI: 10.3389/fpls.2019.00548
    Three transgenic HOSUT lines of winter wheat, HOSUT12, HOSUT20, and HOSUT24, each harbor a single copy of the cDNA for the barley sucrose transporter gene HvSUT1 (SUT), which was fused to the barley endosperm-specific Hordein B1 promoter (HO; the HOSUT transgene). Previously, flow cytometry combined with PCR analysis demonstrated that the HOSUT transgene had been integrated into different wheat chromosomes: 7A, 5D, and 4A in HOSUT12, HOSUT20, and HOSUT24, respectively. In order to confirm the chromosomal location of the HOSUT transgene by a cytological approach using wheat aneuploid stocks, we crossed corresponding nullisomic-tetrasomic lines with the three HOSUT lines, namely nullisomic 7A-tetrasomic 7B with HOSUT12, nullisomic 5D-tetrasomic 5B with HOSUT20, and nullisomic 4A-tetrasomic 4B with HOSUT24. We examined the resulting chromosomal constitutions and the presence of the HOSUT transgene in the F2 progeny by means of chromosome banding and PCR. The chromosome banding patterns of the critical chromosomes in the original HOSUT lines showed no difference from those of the corresponding wild type chromosomes. The presence or absence of the critical chromosomes completely corresponded to the presence or absence of the HOSUT transgene in the F2 plants. Investigating telocentric chromosomes occurred in the F2 progeny, which were derived from the respective critical HOSUT chromosomes, we found that the HOSUT transgene was individually integrated on the long arms of chromosomes 4A, 7A, and 5D in the three HOSUT lines. Thus, in this study we verified the chromosomal locations of the transgene, which had previously been determined by flow cytometry, and moreover revealed the chromosome-arm locations of the HOSUT transgene in the HOSUT lines.
    Matched MeSH terms: Flow Cytometry
  7. MyJurnal
    The present study was to evaluate the toxicity of damnacanthal, nordamnacanthal, betulinic acid and zerumbone isolated from local medicinal plants towards leukemia cell lines and immune cells by using MTT assay and flow cytometry cell cycle analysis. The results showed that damnacanthal significantly inhibited HL-60 cells, CEM-SS and WEHI-3B with the IC50 value of 4.0 µg/mL, 8.0 µg/mL and 3.3 µg/mL, respectively. Nordamnacanthal and betulinic acid showed stronger inhibition towards CEM-SS and HL-60 cells with the IC50 value of 5.7 µg/mL and 5.0 µg/mL, respectively. In contrast, Zerumbone was demonstrated to be more toxic towards those leukemia cells with the IC50 value less than 10 µg/mL. Damnacanthal, nordamnacanthal and betulinic acid were not toxic towards 3T3 and PBMC compared to doxorubicin which showed toxicity effects towards 3T3 and PBMC with the IC50 value of 3.0 µg/mL and 28.0 µg/mL, respectively. The cell cycle analysis exhibited that damnacanthal exerted its toxicity effect towards HL-60 cells by inducing apoptosis with value of 25% after 72 hours treatment. Thus, these compounds could be the potential anticancer drug with less toxic side effect.
    Matched MeSH terms: Flow Cytometry
  8. Lau MF, Vellasamy S, Chua KH, Sabaratnam V, Kuppusamy UR
    EXCLI J, 2018;17:186-199.
    PMID: 29743857 DOI: 10.17179/excli2018-1011
    Colorectal cancer (CRC) is the third most leading cause of morbidity and mortality throughout the world. 5-fluorouracil (5-FU), which is often administrated to disrupt carcinogenesis, was found to elevate blood glucose level among CRC patients. Thus, this study was conducted to evaluate the influence of rosiglitazone on antiproliferative effect of 5-FU using cellular model. Two human colonic carcinoma cell lines (HCT 116 and HT 29) were cultured in the presence of 5-FU, rosiglitazone or in combination under normal and high glucose concentration. The drug cytotoxicity was evaluated using the MTT assay whereas the assessment of cell cycle was carried out using the flow cytometry technique. Combination index (CI) method was used to determine the drug interaction between rosiglitazone and 5-FU. High glucose diminished the cytotoxic effect of 5-FU but at a high drug dosage, this effect could be overcome. Cell cycle analysis demonstrated that 5-FU and rosiglitazone caused G1-phase arrest and S-phase arrest, respectively. CI values indicated that rosiglitazone exerted synergistic effect on 5-FU regardless of glucose levels. This study is the first to demonstrate the influence of rosiglitazone on cytotoxicity of 5-FU under normal or high glucose level. Rosiglitazone may be a promising drug for enhancing the efficacy of 5-FU in the treatment of CRC associated with hyperglycemia.
    Matched MeSH terms: Flow Cytometry
  9. Jee PF, Chen FS, Shu MH, Wong WF, Abdul Rahim R, AbuBakar S, et al.
    Biotechnol Prog, 2017 Jan;33(1):154-162.
    PMID: 27802566 DOI: 10.1002/btpr.2400
    Heterologous protein displayed on the surface of Lactococcus lactis using the binding domain of N-acetylmuramidase (AcmA) has a potential application in vaccine delivery. In this study, we developed a non-recombinant L. lactis surface displaying the influenza A (H1N1) 2009 hemagglutinin (HA1). Three recombinant proteins, HA1/L/AcmA, HA1/AcmA, and HA1 were overexpressed in Escherichia coli, and purified. In the binding study using flow cytometry, the HA1/L/AcmA, which contained the single-chain variable fragment (scFv) peptide linker showed significantly higher percentage of binding counts and mean fluorescence binding intensity (MFI) (51.7 ± 1.4% and 3,594.0 ± 675.9, respectively) in comparison to the HA1/AcmA without the scFv peptide linker (41.1 ± 1.5% and 1,652.0 ± 34.1, respectively). Higher amount of HA1/L/AcmA (∼2.9 × 10(4) molecules per cell) was displayed on L. lactis when compared to HA1/AcmA (∼1.1 × 10(4) molecules per cell) in the immunoblotting analysis. The HA1/L/AcmA completely agglutinated RBCs at comparable amount of protein to that of HA1/AcmA and HA1. Computational modeling of protein structures suggested that scFv peptide linker in HA1/L/AcmA kept the HA1 and the AcmA domain separated at a much longer distance in comparison to HA1/AcmA. These findings suggest that insertion of the scFv peptide linker between HA1 and AcmA improved binding of recombinant proteins to L. lactis. Hence, insertion of scFv peptide linker can be further investigated as a potential approach for improvement of heterologous proteins displayed on the surface of L. lactis using the AcmA binding domain. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 33:154-162, 2017.
    Matched MeSH terms: Flow Cytometry
  10. Zakaria N, Mahdzir MA, Yusoff M, Mohd Arshad N, Awang K, Nagoor NH
    Molecules, 2018 Oct 23;23(11).
    PMID: 30360475 DOI: 10.3390/molecules23112733
    BACKGROUND: Pinnatane A from the bark of Walsura pinnata was investigated for its anti-cancer properties by analyzing the cytotoxic activities and cell cycle arrest mechanism induced in two different liver cancer cell lines.

    METHODS: A 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was used to analyze the pinnatane A selectivity in inducing cell death in cancer and normal cells. Various biological assays were carried out to analyze the anti-cancer properties of pinnatane A, such as a live/dead assay for cell death microscopic visualization, cell cycle analysis using propidium iodide (PI) to identify the cell cycle arrest phase, annexin V-fluorescein isothiocyanate (annexin V-FITC)/PI flow cytometry assay to measure percentage of cell populations at different stages of apoptosis and necrosis, and DNA fragmentation assay to verify the late stage of apoptosis.

    RESULTS: The MTT assay identified pinnatane A prominent dose- and time-dependent cytotoxicity effects in Hep3B and HepG2 cells, with minimal effect on normal cells. The live/dead assay showed significant cell death, while cell cycle analysis showed arrest at the G₀/G₁ phase in both cell lines. Annexin V-FITC/PI flow cytometry and DNA fragmentation assays identified apoptotic cell death in Hep3B and necrotic cell death in HepG2 cell lines.

    CONCLUSIONS: Pinnatane A has the potential for further development as a chemotherapeutic agent prominently against human liver cells.

    Matched MeSH terms: Flow Cytometry
  11. T-Johari SAT, Hashim F, Ismail WI, Ali AM
    Int J Cell Biol, 2019;2019:3059687.
    PMID: 30923553 DOI: 10.1155/2019/3059687
    Combination of natural products with chemodrugs is becoming a trend in discovering new therapeutics approach for enhancing the cancer treatment process. In the present study, we aimed to investigate the cytotoxic and apoptosis induction of Gelam honey (GH) combined with or without 5-Fluorouracil (5-FU) on HT-29 cells. The cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay to assess cytotoxicity. Morphological changes and apoptosis were determined by the inverted microscope, Annexin V-FITC, and DNA fragmentation via flow cytometric analysis, respectively. Our results demonstrate that combined treatment revealed a remarkable and concentration-dependent cytotoxic effect on HT-29 cells in comparison with GH and 5-FU alone. Flow cytometry analysis showed that early apoptosis event was more pronounced in combined treatment. In addition, compared to 5-FU alone, apoptosis of HT-29 cells treated with combinations of GH and 5-FU demonstrated increasing percentages of fragmented DNA. Our results suggest that GH has a synergistic cytotoxic effect with 5-FU in HT-29 cell lines in vitro. Although the actions of the molecular mechanisms are not yet clear, the results reveal that the combination of GH and 5-FU could have the potential as a therapeutic agent.
    Matched MeSH terms: Flow Cytometry
  12. Mohd Nor NH, Berahim Z, Azlina A, Kannan TP
    Clin Oral Investig, 2019 Nov;23(11):3959-3966.
    PMID: 30847574 DOI: 10.1007/s00784-019-02827-x
    OBJECTIVES: This study aimed to differentiate and characterize fibroblast-like cells from stem cells from human exfoliated deciduous teeth (SHED).

    MATERIALS AND METHODS: The differentiation of fibroblast-like cells from SHED was carried out by using specific human recombinant connective tissue growth factor (CTGF). To characterize fibroblastic differentiation, the induced cells were subjected to morphological changes, proliferation rate, gene expression analysis using quantitative reverse transcription-polymerase chain reaction (qRT-PCR), flow cytometry, and immunofluorescence staining. The commercial primary human gingival fibroblasts served as positive control in this study.

    RESULTS: The results from characterization analysis were compared with that of commercial cells to ensure that the cells differentiated from SHED were fibroblast-like cells. The results showed the inductive effect of CTGF for fibroblastic differentiation in SHED. SHED-derived fibroblasts were successfully characterized despite having similar morphological appearance, i.e., (i) significant proliferation rate between fibroblast-like cells and SHED, (ii) high expression of fibroblast-associated markers in qRT-PCR analysis, and (iii) positive staining against collagen type 1, fibroblast-specific protein 1, and human thymic fibroblasts in flow cytometry analysis and immunofluorescence staining. The same expression patterns were found in primary human gingival fibroblasts, respectively. SHED as negative control showed lower expression or no signal, thus confirming the cells differentiated from SHED were fibroblast-like cells.

    CONCLUSIONS: Taken together, the protocol adopted in this study suggests CTGF to be an appropriate inducer in the differentiation of SHED into fibroblast-like cells.

    CLINICAL RELEVANCE: The fibroblast-like cells differentiated from SHED could be used in future in vitro and in vivo dental tissue regeneration studies as well as in clinical applications where these cells are needed.

    Matched MeSH terms: Flow Cytometry
  13. Koosha S, Mohamed Z, Sinniah A, Ibrahim Z, Seyedan A, Alshawsh MA
    Life Sci, 2019 Jul 03.
    PMID: 31278947 DOI: 10.1016/j.lfs.2019.116633
    AIMS: The compound 8-prenylnaringenin (8-PN) is a prenylflavonoid that can be isolated from hops and beer and has anti-cancer properties against breast cancer. The aim of this study is to investigate the anti-proliferative and apoptotic activities of 8-PN against human colon cancer HCT-116 cells.

    MAIN METHODS: Colon cancer HCT-116 cells were treated with 8-PN and subjected to MTT and acridine orange/propidium iodide (AO/PI) staining to investigate the cytotoxicity of 8-PN. Arrest of the cells at different phases of cell cycle was monitored in the presence of 8-PN. Moreover, the apoptotic effects of 8-PN was assessed via annexin V and caspase activity assays and compared to the untreated cells.

    KEY FINDINGS: The findings showed that 8-PN revealed strong inhibitory effect against HCT-116 cells with an IC50 value of 23.83 ± 2.9 μg/ml after 48 h. However, at similar concentrations and experimental time-points, the compound did not show cytotoxic effect to non-cancerous colon cells (CCD-41). Annexin-V assay indicates that 38.5% and 14.4% of HCT-116 cells had entered early and late stages of apoptosis, respectively after exposure of the cells to 8-PN for 48 h. Caspase activity assay illustrates that apoptosis is activated through both intrinsic and extrinsic pathways. Moreover, flow cytometry cell cycle results indicate that treatment with 8-PN significantly arrested the HCT-116 cells at G0/G1 phase.

    SIGNIFICANCE: These findings reveal that 8-PN has anti-proliferative activity against HCT-116 colon cancer cells via induction of intrinsic and extrinsic pathway-mediated apoptosis. Further investigations should be carried out to unravel the mechanistic pathways underlying these activities.

    Matched MeSH terms: Flow Cytometry
  14. Ansari AW, Ahmad F, Shankar EM, Kong YY, Tan HY, Jacobs R, et al.
    PMID: 32398557 DOI: 10.1097/QAI.0000000000002399
    BACKGROUND: We have previously shown an association of elevated co-inhibitory molecule 2B4 expression with iNKT cells alterations in HIV disease. Herein we show a comparative analysis of 2B4 expression on iNKT cells of HIV long-term non-progressors (LTNPs) and progressors.

    METHODS: Anti-retroviral therapy (ART) naïve HIV-seropositive individuals (progressors, n=16) and long-term non-progressors (LTNPs, n=10) were recruited for this study. We employed multi-color flow cytometry on frozen peripheral blood mononuclear cells (PBMCs) to determine iNKT subset frequencies, the levels of co-inhibitory 2B4 expression, and intracellular IFN-γ production. CD1d tetramer was used to characterize iNKT cells.

    RESULTS: We report significantly lower level of 2B4 expression on bulk LTNPs iNKT cells as well as on their CD4 subsets compared to HIV progressors. Furthermore, the iNKT cells from LTNPs produced higher amount of IFN-γ than HIV progressors as detected by intracellular cytokine staining. Interestingly, the frequency of 2B4iNKT cells of progressors but not LTNPs significantly correlates with CD4 T cell count, HIV viral load and IFNγ production by iNKT cells.

    CONCLUSION: Our results suggest that in addition to suppressed HIV replication, diminished 2B4 expression and associated co-inhibitory signaling, and substantial production of IFN-γ could contribute to preserved iNKT cell phenotype in LTNPs.

    Matched MeSH terms: Flow Cytometry
  15. Daker M, Yeo JT, Bakar N, Abdul Rahman AS, Ahmad M, Yeo TC, et al.
    Exp Ther Med, 2016 Jun;11(6):2117-2126.
    PMID: 27284293
    Nasopharyngeal carcinoma (NPC) is a type of tumour that arises from the epithelial cells that line the surface of the nasopharynx. NPC is treated with radiotherapy and cytotoxic chemotherapeutic drugs such as cisplatin and 5-fluorouracil. However, current strategies are often associated with potential toxicities. This has prompted efforts to identify alternative methods of treatment. The present study aimed to investigate silvestrol and episilvestrol-mediated inhibition of cell proliferation in human NPC cells. The growth kinetics of NPC cells treated with silvestrol or episilvestrol were monitored dynamically using a real-time, impedance-based cell analyzer, and dose-response profiles were generated using a colorimetric cell viability assay. Furthermore, apoptosis was evaluated using flow cytometry and high content analysis. In addition, flow cytometry was performed to determine cell cycle distribution. Finally, the effects of combining silvestrol or episilvestrol with cisplatin on NPC cells was examined. Apoptosis was not observed in silvestrol and episilvestrol-treated NPC cells, although cell cycle perturbation was evident. Treatment with both compounds induced a significant increase in the percentage of cells in the G2/M phase, as compared with the control. In vitro cultures combining silvestrol or episilvestrol with cisplatin showed synergistic effects against NPC cells. The results of the present study suggested that silvestrol and episilvestrol had an anti-tumour activity in NPC cells. Silvestrol and episilvestrol, particularly in combination with cisplatin, merit further investigation, so as to determine the cellular mechanisms underlying their action(s) as anti-NPC agents.
    Matched MeSH terms: Flow Cytometry
  16. Vadivelu RK, Yeap SK, Ali AM, Hamid M, Alitheen NB
    PMID: 23056140 DOI: 10.1155/2012/251362
    Betulinic acid is a widely available plant-derived triterpene which is reported to possess selective cytotoxic activity against cancer cells of neuroectodermal origin and leukemia. However, the potential of betulinic acid as an antiproliferative and cytotoxic agent on vascular smooth muscle (VSMC) is still unclear. This study was carried out to demonstrate the antiproliferative and cytotoxic effect of betulinic acid on VSMCs using 3-[4,5-dimethylthizol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry cell cycle assay, BrdU proliferation assay, acridine orange/propidium iodide staining, and comet assay. Result from MTT and BrdU assays indicated that betulinic acid was able to inhibit the growth and proliferation of VSMCs in a dose-dependent manner with IC(50) of 3.8 μg/mL significantly (P < 0.05). Nevertheless, betulinic acid exhibited G(1) cell cycle arrest in flow cytometry cell cycle profiling and low level of DNA damage against VSMC in acridine orange/propidium iodide and comet assay after 24 h of treatment. In conclusion, betulinic acid induced G(1) cell cycle arrest and dose-dependent DNA damage on VSMC.
    Matched MeSH terms: Flow Cytometry
  17. Subramani B, Pullai CR, Krishnan K, Sugadan SD, Deng X, Hiroshi T, et al.
    Biomed Rep, 2014 Jul;2(4):505-508.
    PMID: 24944796
    Immune cell-based therapies using natural killer (NK) cells and cytotoxic T cells are under constant scrutiny, with the aim to design an effective and reduced-toxicity therapy, which will benefit patients via improved quality of life and improved prognosis. Four patients with stage IV colon cancer were administered 1, 3, 5 and 6 effector cell intravenous infusions, respectively. Peripheral blood was collected from the patients and the ex vivo activation and expansion of NK and T cells was performed in Good Manufacturing Practice-certified clean rooms for ~12-15 days. Immunophenotypic analysis of the peripheral blood mononuclear cells (PBMCs) and expanded NK and T cells was conducted using flow cytometry and the patients were followed up. On average, 4.8×107 initial PBMCs and 2.7×109 total expanded cells were obtained. The intravenous infusions of the expanded cells were not accompanied by adverse reactions. Improved prognosis, reflected by a considerable decrease in the cancer markers, accompanied by an improved quality of life in the patients were observed. In conclusion, potential strategies are currently under development for the large-scale production of effectors cells; therefore, autologous immune enhancement therapy (AIET) may be considered as a viable approach to cancer treatment.
    Matched MeSH terms: Flow Cytometry
  18. Ahmad H, Thambiratnam K, Zulkifli AZ, Lawrence A, Jasim AA, Kunasekaran W, et al.
    Sensors (Basel), 2013 Sep 30;13(10):13276-88.
    PMID: 24084118 DOI: 10.3390/s131013276
    An efficient and low cost optical method for directly measuring the concentration of homogenous biological solutes is proposed and demonstrated. The proposed system operates by Fresnel reflection, with a flat-cleaved single-mode fiber serving as the sensor probe. A laser provides a 12.9 dBm sensor signal at 1,550 nm, while a computer-controlled optical power meter measures the power of the signal returned by the probe. Three different mesenchymal stem cell (MSC) lines were obtained, sub-cultured and trypsinized daily over 9 days. Counts were measured using a haemocytometer and the conditioned media (CM) was collected daily and stored at -80 °C. MSCs release excretory biomolecules proportional to their growth rate into the CM, which changes the refractive index of the latter. The sensor is capable of detecting changes in the number of stem cells via correlation to the change in the refractive index of the CM, with the measured power loss decreasing approximately 0.4 dB in the CM sample per average 1,000 cells in the MSC subculture. The proposed system is highly cost-effective, simple to deploy, operate, and maintain, is non-destructive, and allows reliable real-time measurement of various stem cell proliferation parameters.
    Matched MeSH terms: Flow Cytometry/instrumentation
  19. Leong CF, Kalaichelvi AV, Cheong SK, Hamidah NH, Rahman J, Sivagengei K
    Malays J Pathol, 2004 Dec;26(2):111-6.
    PMID: 16329563
    Myeloperoxidase (MPO) is present in azurophilic granules which appear in the promyelocyte stage of differentiation and is expressed in granulomonocytic cells. MPO is usually detected by cytochemistry. The demonstration of peroxidase in at least 3% of bone marrow blasts defines an acute leukaemia as acute myeloblastic leukaemia (AML). MPO is important in distinguishing acute myeloblastic leukaemia (AML) from acute lymphoblastic leukaemia (ALL). It is difficult to diagnose AML with minimal evidence of myeloid differentiation (AML- M0) by conventional light microscopy. However, these AML-M0 blasts can be detected by monoclonal antibodies. Anti-MPO recognizes the enzymatically inactive precursor forms of MPO. There are a few commercially available monoclonal antibodies against MPO. In this study, we evaluated two monoclonal antibodies against MPO from different commercial sources.
    Matched MeSH terms: Flow Cytometry/methods*
  20. Dhaliwal JS, Quek CK, Balasubramaniam T, Nasuruddin BA
    Asian Pac J Allergy Immunol, 1996 Dec;14(2):87-90.
    PMID: 9177821
    The aim of this project was to compare dual and tri-colour reagents for lymphocyte immunophenotyping. A total of 37 patient and normal specimens were immunophenotyped concurrently with the following mean values (% dual vs tri-colour): CD3 (69.4 vs 68.3) CD4 (24.0 vs 24.2) and CD19 (13.9 vs 12.6). A comparison of the results obtained using the paired t test showed that there were no significant differences for cells expressing CD3, CD4 and CD19. However, there was a significant difference in the NK (18.3 vs 16.3) cell component. A major advantage in using 3 colour immunophenotyping is the ability to analyse specimens that cannot be analysed using dual colour reagents due to debris or contamination of the gate with non-lymphocytic cells.
    Matched MeSH terms: Flow Cytometry/methods
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