Displaying publications 301 - 320 of 411 in total

Abstract:
Sort:
  1. Aminuddin A, Ng PY
    Front Pharmacol, 2016;7:244.
    PMID: 27570510 DOI: 10.3389/fphar.2016.00244
    Canonical Wnt signaling pathway, also known as Wnt/β-catenin signaling pathway, is a crucial mechanism for cellular maintenance and development. It regulates cell cycle progression, apoptosis, proliferation, migration, and differentiation. Dysregulation of this pathway correlates with oncogenesis in various tissues including breast, colon, pancreatic as well as head and neck cancers. Furthermore, the canonical Wnt signaling pathway has also been described as one of the critical signaling pathways for regulation of normal stem cells as well as cancer cells with stem cell-like features, termed cancer stem cells (CSC). In this review, we will briefly describe the basic mechanisms of Wnt signaling pathway and its crucial roles in the normal regulation of cellular processes as well as in the development of cancer. Next, we will highlight the roles of canonical Wnt signaling pathway in the regulation of CSC properties namely self-renewal, differentiation, metastasis, and drug resistance abilities, particularly in head and neck squamous cell carcinoma. Finally, we will examine the findings of several recent studies which explore druggable targets in the canonical Wnt signaling pathway which could be valuable to improve the treatment outcome for head and neck cancer.
    Matched MeSH terms: Neoplastic Stem Cells
  2. Cheah PL, Li J, Looi LM, Teoh KH, Ong DB, Arends MJ
    PeerJ, 2018;6:e5530.
    PMID: 30221090 DOI: 10.7717/peerj.5530
    Background: Except for a few studies with contradictory observations, information is lacking on the possibility of association between DNA mismatch repair (MMR) status and the presence of cancer stem cells in colorectal carcinoma (CRC), two important aspects in colorectal carcinogenesis.

    Methods: Eighty (40 right-sided and 40 left-sided) formalin-fixed, paraffin-embedded primary CRC were immunohistochemically studied for CD133, a putative CRC stem cell marker, and MMR proteins MLH1, MSH2, MSH6 and PMS2. CD133 expression was semi-quantitated for proportion of tumor immunopositivity on a scale of 0-5 and staining intensity on a scale of 0-3 with a final score (units) being the product of proportion and intensity of tumor staining. The tumor was considered immunopositive only when the tumor demonstrated moderate to strong intensity of CD133 staining (a decision made after analysis of CD133 expression in normal colon). Deficient MMR (dMMR) was interpreted as unequivocal loss of tumor nuclear staining for any MMR protein despite immunoreactivity in the internal positive controls.

    Results: CD133 was expressed in 36 (90.0%) left-sided and 28 (70.0%) right-sided tumors (p  0.05).

    Conclusion: Proficient MMR correlated with high levels of CD133-marked putative cancer stem cells in both right- and left-sided tumors, whereas significantly lower levels of CD133-marked putative cancer stem cells were associated with deficient MMR status in colorectal carcinomas found on the right.

    Matched MeSH terms: Neoplastic Stem Cells
  3. 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: Pluripotent Stem Cells
  4. 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: Stem Cells
  5. Ong SB, Lee WH, Shao NY, Ismail NI, Katwadi K, Lim MM, et al.
    Stem Cell Reports, 2019 03 05;12(3):597-610.
    PMID: 30799273 DOI: 10.1016/j.stemcr.2019.01.017
    The relationship between diabetes and endothelial dysfunction remains unclear, particularly the association with pathological activation of calpain, an intracellular cysteine protease. Here, we used human induced pluripotent stem cells-derived endothelial cells (iPSC-ECs) to investigate the effects of diabetes on vascular health. Our results indicate that iPSC-ECs exposed to hyperglycemia had impaired autophagy, increased mitochondria fragmentation, and was associated with increased calpain activity. In addition, hyperglycemic iPSC-ECs had increased susceptibility to cell death when subjected to a secondary insult-simulated ischemia-reperfusion injury (sIRI). Importantly, calpain inhibition restored autophagy and reduced mitochondrial fragmentation, concurrent with maintenance of ATP production, normalized reactive oxygen species levels and reduced susceptibility to sIRI. Using a human iPSC model of diabetic endotheliopathy, we demonstrated that restoration of autophagy and prevention of mitochondrial fragmentation via calpain inhibition improves vascular integrity. Our human iPSC-EC model thus represents a valuable platform to explore biological mechanisms and new treatments for diabetes-induced endothelial dysfunction.
    Matched MeSH terms: Induced Pluripotent Stem Cells
  6. Chum JD, Lim DJZ, Sheriff SO, Pulikkotil SJ, Suresh A, Davamani F
    Restor Dent Endod, 2019 Feb;44(1):e8.
    PMID: 30834230 DOI: 10.5395/rde.2019.44.e8
    Objectives: Irrigants are imperative in endodontic therapy for the elimination of pathogens from the infected root canal. The present study compared the antimicrobial efficacy of octenidine dihydrochloride (OCT) with chlorhexidine (CHX) and sodium hypochlorite (NaOCl) against Staphylococcus epidermidis (S. epidermidis) for root canal disinfection.

    Materials and Methods: The minimum inhibitory concentration (MIC) was obtained using serial dilution method. The agar diffusion method was then used to determine the zones of inhibition for each irrigant. Lastly, forty 6-mm dentin blocks were prepared from human mandibular premolars and inoculated with S. epidermidis. Samples were randomly divided into 4 groups of 10 blocks and irrigated for 3 minutes with saline (control), 2% CHX, 3% NaOCl, or 0.1% OCT. Dentin samples were then collected immediately for microbial analysis, including an analysis of colony-forming units (CFUs).

    Results: The MICs of each tested irrigant were 0.05% for CHX, 0.25% for NaOCl, and 0.0125% for OCT. All tested irrigants showed concentration-dependent increase in zones of inhibition, and 3% NaOCl showed the largest zone of inhibition amongst all tested irrigants (p < 0.05). There were no significant differences among the CFU measurements of 2% CHX, 3% NaOCl, and 0.1% OCT showing complete elimination of S. epidermidis in all samples.

    Conclusions: This study showed that OCT was comparable to or even more effective than CHX and NaOCl, demonstrating antimicrobial activity at low concentrations against S. epidermidis.

    Matched MeSH terms: Stem Cells
  7. 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: Stem Cells
  8. Kuan TLT, Amini F, Seghayat MS
    Iran J Basic Med Sci, 2017 Jul;20(7):729-738.
    PMID: 28852436 DOI: 10.22038/IJBMS.2017.9000
    Multiple sclerosis is a debilitating disease of the central nervous system. It affects people of all ages but is more prevalent among 20-40 year olds. Patients with MS can be presented with potentially any neurological symptom depending on the location of the lesion. A quarter of patients with MS suffer from bilateral lower limb spasticity among other symptoms. These devastating effects can be detrimental to the patient's quality of life. Hematopoietic stem cells (HSCs) have been used as a treatment for MS over the past 2 decades but their safety and efficacy has are undetermined. The objective of this study is to evaluate the feasibility and toxicity of autologous HSCs transplantation in MS. A literature search was done from 1997 to 2016 using different keywords. A total of 9 articles, which met the inclusion and exclusion criteria, were included in this review. The type of conditioning regimen and technique of stem cell mobilization are summarized and compared in this study. All studies reported high-dose immunosuppressive therapy with autologous HSCs transplantation being an effective treatment option for severe cases of multiple sclerosis. Fever, sepsis, and immunosuppression side effects were the most observed adverse effects that were reported in the selected studies. HSCs is a feasible treatment for patients with MS; nevertheless the safety is still a concern due to chemo toxicity.
    Matched MeSH terms: Hematopoietic Stem Cells
  9. Varadan P, Ganesh A, Konindala R, Nagendrababu V, Ashok R, Deivanayagam K
    Cureus, 2017 Oct 26;9(10):e1805.
    PMID: 29308333 DOI: 10.7759/cureus.1805
    Introduction Root canal irrigants play an important role in reducing intracanal microorganisms, which in turn helps in achieving a successful outcome for the root canal treatment. Objective To compare the antibacterial efficacy of alexidine and chlorhexidine against Enterococcus faecalis. Methods A total of 50 extracted single-rooted teeth were randomly divided into five groups after being infected with Enterococcus faecalis. The groups were based on irrigants used: Group I - 0.4% alexidine; Group II - 1% alexidine; Group III - 1.5% percent alexidine; Group IV - 2% alexidine; Group V - 2% chlorhexidine. Following irrigation, colony-forming units were determined from the dentinal shavings collected at 400 µm depth. Results Use of 2% alexidine reduced the bacteria effectively when compared to 0.4%, 1%, and 1.5% alexidine. A statistically significant difference was not observed between 2% alexidine and 2% chlorhexidine. Discussion Alexidine, due to its higher virulence factors for bacteria and better bacterial penetrability at 400 µm depth of dentin showed better eradication of Enterococcus faecalis in comparison to chlorhexidine. Conclusion The use of 2% alexidine against Enterococcus faecalis at 400 µm depth of dentin has efficacy comparable to chlorhexidine. Hence, alexidine can be used as an alternative irrigant for chlorhexidine during endodontic procedures.
    Matched MeSH terms: Stem Cells
  10. Dewi R, Yusoff NA, Abdul Razak SR, Abd Hamid Z
    PeerJ, 2023;11:e15608.
    PMID: 37456886 DOI: 10.7717/peerj.15608
    BACKGROUND: HSPCs are targets for benzene-induced hematotoxicity and leukemogenesis. However, benzene toxicity targeting microRNAs (miRNAs) and transcription factors (TF) that are involve in regulating self-renewing and differentiation of HSPCs comprising of different hematopoietic lineages remains poorly understood. In this study, the effect of a benzene metabolite, 1,4-benzoquinone (1,4-BQ) exposure, in HSPCs focusing on the self-renewing (miRNAs: miR-196b and miR-29a; TF: HoxB4, Bmi-1) and differentiation (miRNAs: miR-181a, TF: GATA3) pathways were investigated.

    METHODS: Freshly isolated mouse BM cells were initially exposed to 1,4-BQ at 1.25 to 5 µM for 24 h, followed by miRNAs and TF studies in BM cells. Then, the miRNAs expression was further evaluated in HSPCs of different lineages comprised of myeloid, erythroid and pre-B lymphoid progenitors following 7-14 days of colony forming unit (CFU) assay.

    RESULTS: Exposure to 1,4-BQ in BM cells significantly (p 

    Matched MeSH terms: Hematopoietic Stem Cells
  11. Mahkamova K, Latar NM, Aspinall S, Meeson A
    Exp Cell Res, 2019 01 01;374(1):104-113.
    PMID: 30465733 DOI: 10.1016/j.yexcr.2018.11.012
    Comparison of studies of cells derived from normal and pathological tissues of the same organ can be fraught with difficulties, particular with cancer where a number of different diseases are considered cancer within the same tissue. In the thyroid, there are 4 main types of cancer, three of which arise from follicular epithelial cells; papillary and follicular which are classified as differentiated, and anaplastic which is classified as undifferentiated. One assay that can be utilised for isolation of cancer stem cells is the side population (SP) assay. However, SP studies have been limited in part due to lack of optimal isolation strategies and in the case of anaplastic thyroid cancer (ATC) are further compounded by lack of access to ATC tumors. We have used thyroid cell lines to determine the optimal conditions to isolate viable SP cells. We then compared SP cells and NSP cells (bulk tumour cells without the SP) of a normal thyroid cell line N-thy ori-3-1 and an anaplastic thyroid cancer cell line SW1736 and showed that both SP cell populations displayed higher levels of stem cell characteristics than the NSP. When we compared SP cells of the N-thy ori-3-1 and the SW1736, the SW1736 SP had a higher colony forming potential, expressed higher levels of stem cell markers and CXCR4 and where more migratory and invasive, invasiveness increasing in response to CXCL12. This is the first report showing functional differences between ATC SP and normal thyroid SP and could lead to the identification of new therapeutic targets to treat ATC.
    Matched MeSH terms: Neoplastic Stem Cells/drug effects; Neoplastic Stem Cells/metabolism; Neoplastic Stem Cells/pathology
  12. Zainol Abidin IZ, Manogaran T, Abdul Wahab RM, Karsani SA, Yazid MD, Yazid F, et al.
    Curr Stem Cell Res Ther, 2023;18(3):417-428.
    PMID: 35762553 DOI: 10.2174/1574888X17666220627145424
    BACKGROUND: Proteomic is capable of elucidating complex biological systems through protein expression, function, and interaction under a particular condition.

    OBJECTIVE: This study aimed to determine the potential of ascorbic acid alone in inducing differentially expressed osteoblast-related proteins in dental stem cells via the liquid chromatography-mass spectrometry/ mass spectrometry (LC-MS/MS) approach.

    METHODS: The cells were isolated from deciduous (SHED) and permanent teeth (DPSC) and induced with 10 μg/mL of ascorbic acid. Bone mineralisation and osteoblast gene expression were determined using von Kossa staining and reverse transcriptase-polymerase chain reaction. The label-free protein samples were harvested on days 7 and 21, followed by protein identification and quantification using LC-MS/MS. Based on the similar protein expressed throughout treatment and controls for SHED and DPSC, overall biological processes followed by osteoblast-related protein abundance were determined using the PANTHER database. STRING database was performed to determine differentially expressed proteins as candidates for SHED and DPSC during osteoblast development.

    RESULTS: Both cells indicated brownish mineral stain and expression of osteoblast-related genes on day 21. Overall, a total of 700 proteins were similar among all treatments on days 7 and 21, with 482 proteins appearing in the PANTHER database. Osteoblast-related protein abundance indicated 31 and 14 proteins related to SHED and DPSC, respectively. Further analysis by the STRING database identified only 22 and 11 proteins from the respective group. Differential expressed analysis of similar proteins from these two groups revealed ACTN4 and ACTN1 as proteins involved in both SHED and DPSC. In addition, three (PSMD11/RPN11, PLS3, and CLIC1) and one (SYNCRIP) protein were differentially expressed specifically for SHED and DPSC, respectively.

    CONCLUSION: Proteome differential expression showed that ascorbic acid alone could induce osteoblastrelated proteins in SHED and DPSC and generate specific differentially expressed protein markers.

    Matched MeSH terms: Stem Cells
  13. Shima WN, Ali AM, Subramani T, Mohamed Alitheen NB, Hamid M, Samsudin AR, et al.
    Exp Ther Med, 2015 Jun;9(6):2202-2206.
    PMID: 26136960
    Mesenchymal stem cells (MSCs) are involved in bone formation in the embryo, bone repair and remodeling. The differentiation of these cells is a complex multistep pathway that involves discrete cellular transitions and is similar to that which occurs during hematopoiesis. MSCs have self-renewal capacity without differentiation in long-term culture. In the present study, MSCs were isolated from human bone marrow and characterized by the presence of cluster of differentiation 105 marker using the labeled streptavidin biotin method. The MSCs were cultured in Dulbecco's modified Eagle's medium supplemented with fetal bovine serum, ascorbic acid, β-glycerol phosphate and dexamethasone to differentiate into osteoblasts. Biological in vitro analysis showed the rapid proliferation of the MSCs. Further evaluation of specific osteogenic markers using von Kossa staining and the alkaline phosphate assay demonstrated that the MSCs were stimulated to differentiate into osteoblast-lineage cells. This mesengenic potential indicated that the bone marrow-derived cells were multipotent MSCs. The findings of this study show that bone marrow can be a legitimate source of MSCs for the production of osteoblasts for utilization in bone replacement therapy.
    Matched MeSH terms: Multipotent Stem Cells
  14. Lim MN, Hussin NH, Othman A, Umapathy T, Baharuddin P, Jamal R, et al.
    Mol Vis, 2012;18:1289-300.
    PMID: 22665977
    The presence of multipotent human limbal stromal cells resembling mesenchymal stromal cells (MSC) provides new insights to the characteristic of these cells and its therapeutic potential. However, little is known about the expression of stage-specific embryonic antigen 4 (SSEA-4) and the embryonic stem cell (ESC)-like properties of these cells. We studied the expression of SSEA-4 surface protein and the various ESC and MSC markers in the ex vivo cultured limbal stromal cells. The phenotypes and multipotent differentiation potential of these cells were also evaluated.
    Matched MeSH terms: Multipotent Stem Cells/cytology*; Multipotent Stem Cells/metabolism; Embryonic Stem Cells
  15. Zahedi FD, Asmi NH, Husain S, Gendeh BS
    Indian J Otolaryngol Head Neck Surg, 2019 Nov;71(Suppl 3):1837-1842.
    PMID: 31763256 DOI: 10.1007/s12070-017-1219-x
    Nasal irrigation is an effective and cheap method in managing post sinonasal surgery patients. It works by improving ciliary clearance and performing mechanical debridement of the thick crust, decreasing mucosal edema and reducing the inflammatory mediators. Presence of nasal irrigation bottle contamination and its effect on patients have been studied. The aim of this study is to prospectively identify the risk of contamination in the nasal irrigation bottle, fluid from the bottle and to correlate with endoscopic findings from the patients who had underwent sinonasal surgery. Swabs will be taken from the nasal irrigation bottle and patient's middle meatus before the surgery and at each post surgery visits (2 and 4 weeks). Patients will be advised to irrigate their nose three times per day post sinonasal surgery. During endoscopic examination of the patient's nasal cavity at 2 and 4 weeks, any evidence of infection will be noted and documented. Additionally, a swab of fluid irrigated from the nasal cavity collected during the clinic follow-ups will also be taken. The specimens will be sent to the Microbiology laboratory for standard culture and sensitivity test. A total of 27 patients completed the study and were divided into case (n = 15) and control (n = 12) groups. The CFU (colony-forming unit) value of the bacteria cultured from the nasal cavity and the nasal irrigation bottle was statistically significantly (P = 0.00) increased from the baseline to the second week follow-up in both groups but not from the second week to the fourth week follow-up. The majority of the swabs from the nasal cavity of the patients and the nasal irrigation bottles were positively cultured for Pseudomonas sp. group. Other groups of bacteria that were cultured were Enterobacter sp., Coagulase Negative Staphylococcus (CONS) and Klebsiella sp. Endoscopically, there was no clinical evidence of infection found in the nasal cavity of the patients. The nasal irrigation bottle that was used in the post sinonasal surgery treatment and for alleviation of symptoms of sinonasal diseases was found to have bacterial contamination from the swabs taken from the bottle. However, despite this finding there was not clinical evidence of infection noted from the nasal endoscopic examination. A simple and effective method of cleaning the bottle would be helpful to reduce the bacterial contamination for this useful treatment method.
    Matched MeSH terms: Stem Cells
  16. Ngadiono E, Hardiany NS
    Malays J Med Sci, 2019 Jul;26(4):5-16.
    PMID: 31496889 DOI: 10.21315/mjms2019.26.4.2
    A glioma, especially a grade IV glioblastoma, is a malignant tumour with a poor prognosis despite growing medical advancements. Researchers have been looking for better and more effective treatments targeting the molecular pathways of gliomas due to glioblastomas' ability to develop resistance to chemotherapies. Moreover, glioma stem cells (GSC) contribute to maintaining the glioma population, which benefits from its ability to self-renew and differentiate. Recent research has reported that through the introduction of umbilical cord mesenchymal stem cells (UCMSC) into glioma cells, the growth and development of the glioma cells can be downregulated. It has more currently been found out that UCMSC release extracellular vesicles (EVs) containing miRNA that are responsible for this phenomenon. Therefore, this review analyses literature to discuss all possible miRNAs contained within the UCMSC's EVs and to elaborate on their molecular mechanisms in halting gliomas and GSC growth. This review will also include the challenges and limitations, to account for which more in vivo research is suggested. In conclusion, this review highlights how miRNAs contained within UCMSC's EVs are able to downregulate multiple prominent pathways in the survival of gliomas.
    Matched MeSH terms: Neoplastic Stem Cells
  17. Ude CC, Shamsul BS, Ng MH, Chen HC, Norhamdan MY, Aminuddin BS, et al.
    Tissue Cell, 2012 Jun;44(3):156-63.
    PMID: 22402173 DOI: 10.1016/j.tice.2012.02.001
    Tracking of transplanted cells has become an important procedure in cell therapy. We studied the in vitro dye retention, survival and in vivo tracking of stem cells with PKH26 dye. Sheep BMSCs and ADSCs were labeled with 2, 4 and 8 μmol of PKH26 and monitored for six passages. Labeled BMSCs and ADSCs acquired mean cumulative population doubling of 12.7±0.4 and 14.6±0.5; unlabeled samples had 13.8±0.5 and 15.4±0.6 respectively. Upon staining with 2, 4 and 8 μmol PKH26, BMSCs had retentions of 40.0±5.8, 60.0±2.9 and 95.0±2.9%, while ADSCs had 92.0±1.2, 95.0±1.2 and 98.0±1.2%. ADSCs retentions were significantly higher at 2 and 4 μmol. On dye retention comparison at 8 μmol and 4 μmol for BMSCs and ADSCs; ADSCs were significantly higher at passages 2 and 3. The viability of BMSCs reduced from 94.0±1.2% to 90.0±0.6% and ADSCs from 94.0±1.2% to 52.0±1.2% (p<0.05) after 24h. BMSCs had significant up regulation of the cartilage genes for both the labeled and the unlabeled samples compared to ADSCs (p<0.05). PKH26 fluorescence was detected on the resected portions of the regenerated neo-cartilage. The recommended concentration of PKH26 for ADSCs is 2 μmol and BMSCs is 8 μmol, and they can be tracked up to 49 days.
    Matched MeSH terms: Stem Cells/chemistry*
  18. Salem SA, Hwei NM, Bin Saim A, Ho CC, Sagap I, Singh R, et al.
    J Biomed Mater Res A, 2013 Aug;101(8):2237-47.
    PMID: 23349110 DOI: 10.1002/jbm.a.34518
    The chief obstacle for reconstructing the bladder is the absence of a biomaterial, either permanent or biodegradable, that will function as a suitable scaffold for the natural process of regeneration. In this study, polylactic-co-glycolic acid (PLGA) plus collagen or fibrin was evaluated for its suitability as a scaffold for urinary bladder construct. Human adipose-derived stem cells (HADSCs) were cultured, followed by incubation in smooth muscle cells differentiation media. Differentiated HADSCs were then seeded onto PLGA mesh supported with collagen or fibrin. Evaluation of cell-seeded PLGA composite immersed in culture medium was performed under a light and scanning microscope. To determine if the composite is compatible with the urodynamic properties of urinary bladder, porosity and leaking test was performed. The PLGA samples were subjected to tensile testing was pulled until PLGA fibers break. The results showed that the PLGA composite is biocompatible to differentiated HADSCs. PLGA-collagen mesh appeared to be optimal as a cell carrier while the three-layered PLGA-fibrin composite is better in relation to its leaking/ porosity property. A biomechanical test was also performed for three-layered PLGA with biological adhesive and three-layered PLGA alone. The tensile stress at failure was 30.82 ± 3.80 (MPa) and 34.36 ± 2.57 (MPa), respectively. Maximum tensile strain at failure was 19.42 ± 2.24 (mm) and 23.06 ± 2.47 (mm), respectively. Young's modulus was 0.035 ± 0.0083 and 0.043 ± 0.012, respectively. The maximum load at break was 58.55 ± 7.90 (N) and 65.29 ± 4.89 (N), respectively. In conclusion, PLGA-Fibrin fulfils the criteria as a scaffold for urinary bladder reconstruction.
    Matched MeSH terms: Stem Cells/cytology
  19. Nordin F, Idris MRM, Mahdy ZA, Wahid SFA
    BMC Pregnancy Childbirth, 2020 Jul 10;20(1):399.
    PMID: 32650736 DOI: 10.1186/s12884-020-03084-7
    BACKGROUND: Umbilical cord blood (UCB) has been proposed as the potential source of haematopoietic stem cells (HSC) for allogeneic transplantation. However, few studies have shown that a common disease in pregnancy such as preeclampsia would affect the quality of UCB-HSC. Total nucleated cell count (TNC) is an important parameter that can be used to predict engraftment including UCB banking. Colony forming unit (CFU) assay is widely used as an indicator to predict the success of engraftment, since direct quantitative assay for HSC proliferation is unavailable. The aim of this study is to investigate the effects of preeclampsia in pregnancy on the stemness and differentiation potency of UCB-HSC.

    METHODS: Mononuclear cells (MNC) were isolated from UCB and further enriched for CD34+ cells using immune-magnetic method followed by CFU assay. A panel of HSC markers including differentiated haematopoietic markers were used to confirm the differentiation ability of UCB-HSC by flow cytometry analysis.

    RESULTS/ DISCUSSION: The HSC progenitor's colonies from the preeclampsia group were significantly lower compared to the control. This correlates with the low UCB volume, TNC and CD34+ cells count. In addition, the UCB-enriched CD34+ population were lymphoid progenitors and capable to differentiate into natural killer cells and T-lymphocytes.

    CONCLUSION: These findings should be taken into consideration when selecting UCB from preeclamptic mothers for banking and predicting successful treatment related to UCB transplant.

    Matched MeSH terms: Hematopoietic Stem Cells/cytology*
  20. Yeo Y, Tan JBL, Lim LW, Tan KO, Heng BC, Lim WL
    Biomed Res Int, 2019;2019:3126376.
    PMID: 33204680 DOI: 10.1155/2019/3126376
    In the biomedical field, there is growing interest in using human stem cell-derived neurons as in vitro models for pharmacological and toxicological screening of bioactive compounds extracted from natural products. Lignosus rhinocerus (Tiger Milk Mushroom) is used by indigenous communities in Malaysia as a traditional medicine to treat various diseases. The sclerotium of L. rhinocerus has been reported to have medicinal properties, including various bioactivities such as neuritogenic, anti-inflammatory, and anticancer effects. This study aims to investigate the neuroprotective activities of L. rhinocerus sclerotial extracts. Human embryonic stem cell (hESC)-derived neural lineages exposed to the synthetic glucocorticoid, dexamethasone (DEX), were used as the in vitro models. Excess glucocorticoids have been shown to adversely affect fetal brain development and impair differentiation of neural progenitor cells. Screening of different L. rhinocerus sclerotial extracts and DEX on the hESC-derived neural lineages was conducted using cell viability and neurite outgrowth assays. The neuroprotective effects of L. rhinocerus sclerotial extracts against DEX were further evaluated using apoptosis assays and Western blot analysis. Hot aqueous and methanol extracts of L. rhinocerus sclerotium promoted neurite outgrowth of hESC-derived neural stem cells (NSCs) with negligible cytotoxicity. Treatment with DEX decreased viability of NSCs by inducing apoptosis. Coincubation of L. rhinocerus methanol extract with DEX attenuated the DEX-induced apoptosis and reduction in phospho-Akt (pAkt) level in NSCs. These results suggest the involvement of Akt signaling in the neuroprotection of L. rhinocerus methanol extract against DEX-induced apoptosis in NSCs. Methanol extract of L. rhinocerus sclerotium exhibited potential neuroprotective activities against DEX-induced toxicity in hESC-derived NSCs. This study thus validates the use of human stem cell-derived neural lineages as potential in vitro models for screening of natural products with neuroprotective properties.
    Matched MeSH terms: Human Embryonic Stem Cells*
Filters
Contact Us

Please provide feedback to Administrator ([email protected])

External Links