Displaying publications 161 - 180 of 277 in total

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  1. Ngan CL, Basri M, Tripathy M, Abedi Karjiban R, Abdul-Malek E
    Eur J Pharm Sci, 2015 Apr 5;70:22-8.
    PMID: 25619806 DOI: 10.1016/j.ejps.2015.01.006
    Despite the fact that intrinsic oxidative stress is inevitable, the extrinsic factor such as ultraviolet radiation enhances reactive oxygen species (ROS) generation resulting in premature skin aging. Nanoemulsion was loaded with fullerene, a strong free radical scavenger, and its efficacy to provide protection and regenerative effect against ROS-induced collagen breakdown in human skin was studied. Stable fullerene nanoemulsions were formulated using high shear homogenization and ultrasonic dispersion technique. An open trial was conducted using fullerene nanoemulsion on skin twice a day for 28 days. The mean collagen score significantly increased (P<0.05) from 36.53±4.39 to 48.69±5.46 with 33.29% increment at the end of the treatment. Biophysical characteristics of skin revealed that skin hydration was increased significantly (P<0.05) from 40.91±7.01 to 58.55±6.08 corneometric units (43.12% increment) and the water was able to contain within the stratum corneum without any increased in transepidermal water loss. In the in vitro safety evaluation, fullerene nanoemulsion showed no acute toxicity on 3T3 fibroblast cell line for 48h and no indication of potential dermal irritation. Hence, the fullerene nanoemulsion may assist in protecting collagen from breakdown with cosmeceutical benefit.
    Matched MeSH terms: Collagen/physiology*; Collagen/chemistry
  2. Sulong AF, Hassan NH, Hwei NM, Lokanathan Y, Naicker AS, Abdullah S, et al.
    Adv Clin Exp Med, 2014 May-Jun;23(3):353-62.
    PMID: 24979505
    Autologous nerve grafts to bridge nerve gaps pose various drawbacks. Nerve tissue engineering to promote nerve regeneration using artificial neural conduits has emerged as a promising alternative.
    Matched MeSH terms: Collagen/metabolism*; Collagen/ultrastructure
  3. Awang MA, Firdaus MA, Busra MB, Chowdhury SR, Fadilah NR, Wan Hamirul WK, et al.
    Biomed Mater Eng, 2014;24(4):1715-24.
    PMID: 24948455 DOI: 10.3233/BME-140983
    Earlier studies in our laboratory demonstrated that collagen extracted from ovine tendon is biocompatible towards human dermal fibroblast. To be able to use this collagen as a scaffold in skin tissue engineering, a mechanically stronger scaffold is required that can withstand manipulation before transplantation. This study was conducted to improve the mechanical strength of this collagen sponge using chemical crosslinkers, and evaluate their effect on physical, chemical and biocompatible properties. Collagen sponge was crosslinked with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and glutaraldehyde (GA). Tensile test, FTIR study and mercury porosimetry were used to evaluate mechanical properties, chemical property and porosity, respectively. MTT assay was performed to evaluate the cytotoxic effect of crosslinked collagen sponge on human dermal fibroblasts. The FTIR study confirmed the successful crosslinking of collagen sponge. Crosslinking with EDC and GA significantly increased the mechanical strength of collagen sponge, with GA being more superior. Crosslinking of collagen sponge significantly reduced the porosity and the effect was predominant in GA-crosslinked collagen sponge. The GA-crosslinked collagen showed significantly lower, 60% cell viability towards human dermal fibroblasts compared to that of EDC-crosslinked collagen, 80% and non-crosslinked collagen, 100%. Although the mechanical strength was better when using GA but the more toxic effect on dermal fibroblast makes EDC a more suitable crosslinker for future skin tissue engineering.
    Matched MeSH terms: Collagen/toxicity*; Collagen/chemistry
  4. Makpol S, Jam FA, Khor SC, Ismail Z, Mohd Yusof YA, Ngah WZ
    Oxid Med Cell Longev, 2013;2013:298574.
    PMID: 24396567 DOI: 10.1155/2013/298574
    Biodynes, tocotrienol-rich fraction (TRF), and tocopherol have shown antiaging properties. However, the combined effects of these compounds on skin aging are yet to be investigated. This study aimed to elucidate the skin aging effects of biodynes, TRF, and tocopherol on stress-induced premature senescence (SIPS) model of human diploid fibroblasts (HDFs) by determining the expression of collagen and MMPs at gene and protein levels. Primary HDFs were treated with biodynes, TRF, and tocopherol prior to hydrogen peroxide (H2O2) exposure. The expression of COL1A1, COL3A1, MMP1, MMP2, MMP3, and MMP9 genes was determined by qRT-PCR. Type I and type III procollagen proteins were measured by Western blotting while the activities of MMPs were quantified by fluorometric Sensolyte MMP Kit. Our results showed that biodynes, TRF, and tocopherol upregulated collagen genes and downregulated MMP genes (P < 0.05). Type I procollagen and type III procollagen protein levels were significantly increased in response to biodynes, TRF, and tocopherol treatment (P < 0.05) with reduction in MMP-1, MMP-2, MMP-3, and MMP-9 activities (P < 0.05). These findings indicated that biodynes, TRF, and tocopherol effectively enhanced collagen synthesis and inhibited collagen degradation and therefore may protect the skin from aging.
    Matched MeSH terms: Collagen/biosynthesis*; Collagen/genetics
  5. Othman MI, Majid MI, Singh M, Man CN, Lay-Harn G
    Ann. Clin. Biochem., 2008 May;45(Pt 3):299-306.
    PMID: 18482919 DOI: 10.1258/acb.2007.007104
    Infiltrating ductal carcinoma (IDCA) is the most common type of breast cancer accounting for 85% of all invasive breast cancers.
    Matched MeSH terms: Collagen Type I/analysis; Collagen Type I/isolation & purification
  6. Munirah S, Kim SH, Ruszymah BH, Khang G
    Eur Cell Mater, 2008 Feb 21;15:41-52.
    PMID: 18288632
    Our preliminary results indicated that fibrin and poly(lactic-co-glycolic acid) (PLGA) hybrid scaffold promoted early chondrogenesis of articular cartilage constructs in vitro. The aim of this study was to evaluate in vivo cartilaginous tissue formation by chondrocyte-seeded fibrin/PLGA hybrid scaffolds. PLGA scaffolds were soaked carefully, in chondrocyte-fibrin suspension, and polymerized by dropping thrombin-calcium chloride (CaCl2) solution. PLGA-seeded chondrocytes were used as a control. Resulting constructs were implanted subcutaneously, at the dorsum of nude mice, for 4 weeks. Macroscopic observation, histological evaluation, gene expression and sulphated-glycosaminoglycan (sGAG) analyses were performed at each time point of 1, 2 and 4 weeks post-implantation. Cartilaginous tissue formation in fibrin/PLGA hybrid construct was confirmed by the presence of lacunae and cartilage-isolated cells embedded within basophilic ground substance. Presence of proteoglycan and glycosaminoglycan (GAG) in fibrin/PLGA hybrid constructs was confirmed by positive Safranin O and Alcian Blue staining. Collagen type II exhibited intense immunopositivity at the pericellular matrices. Chondrogenic properties were further demonstrated by the expression of gene encoded cartilage-specific markers, collagen type II and aggrecan core protein. The sGAG production in fibrin/PLGA hybrid constructs was higher than in the PLGA group. In conclusion, fibrin/PLGA hybrid scaffold promotes cartilaginous tissue formation in vivo and may serve as a potential cell delivery vehicle and a structural basis for articular cartilage tissue-engineering.
    Matched MeSH terms: Collagen Type II/genetics; Collagen Type II/metabolism
  7. Hamid AA, Idrus RB, Saim AB, Sathappan S, Chua KH
    Clinics (Sao Paulo), 2012;67(2):99-106.
    PMID: 22358233
    OBJECTIVES: Understanding the changes in chondrogenic gene expression that are involved in the differentiation of human adipose-derived stem cells to chondrogenic cells is important prior to using this approach for cartilage repair. The aims of the study were to characterize human adipose-derived stem cells and to examine chondrogenic gene expression after one, two, and three weeks of induction.

    MATERIALS AND METHODS: Human adipose-derived stem cells at passage 4 were evaluated by flow cytometry to examine the expression of surface markers. These adipose-derived stem cells were tested for adipogenic and osteogenic differentiation capacity. Ribonucleic acid was extracted from the cells for quantitative polymerase chain reaction analysis to determine the expression levels of chondrogenic genes after chondrogenic induction.

    RESULTS: Human adipose-derived stem cells were strongly positive for the mesenchymal markers CD90, CD73, CD44, CD9, and histocompatibility antigen and successfully differentiated into adipogenic and osteogenic lineages. The human adipose-derived stem cells aggregated and formed a dense matrix after chondrogenic induction. The expression of chondrogenic genes (collagen type II, aggrecan core protein, collagen type XI, COMP, and ELASTIN) was significantly higher after the first week of induction. However, a significantly elevated expression of collagen type X was observed after three weeks of chondrogenic induction.

    CONCLUSION: Human adipose-derived stem cells retain stem cell characteristics after expansion in culture to passage 4 and serve as a feasible source of cells for cartilage regeneration. Chondrogenesis in human adipose-derived stem cells was most prominent after one week of chondrogenic induction.

    Matched MeSH terms: Collagen/genetics; Collagen/metabolism*
  8. Feng Z, Wagatsuma Y, Kikuchi M, Kosawada T, Nakamura T, Sato D, et al.
    Biomaterials, 2014 Sep;35(28):8078-91.
    PMID: 24976242 DOI: 10.1016/j.biomaterials.2014.05.072
    Fibroblast-mediated compaction of collagen gels attracts extensive attention in studies of wound healing, cellular fate processes, and regenerative medicine. However, the underlying mechanism and the cellular mechanical niche still remain obscure. This study examines the mechanical behaviour of collagen fibrils during the process of compaction from an alternative perspective on the primary mechanical interaction, providing a new viewpoint on the behaviour of populated fibroblasts. We classify the collagen fibrils into three types - bent, stretched, and adherent - and deduce the respective equations governing the mechanical behaviour of each type; in particular, from a putative principle based on the stationary state of the instantaneous Hamiltonian of the mechanotransduction system, we originally quantify the stretching force exerted on each stretched fibrils. Via careful verification of a structural elementary model based on this classification, we demonstrate a clear physical picture of the compaction process, quantitatively elucidate the panorama of the micro mechanical niche and reveal an intrinsic biphasic relationship between cellular traction force and matrix elasticity. Our results also infer the underlying mechanism of tensional homoeostasis and stress shielding of fibroblasts. With this study, and sequel investigations on the putative principle proposed herein, we anticipate a refocus of the research on cellular mechanobiology, in vitro and in vivo.
    Matched MeSH terms: Collagen/chemistry*
  9. Dhiyaaldeen SM, Alshawsh MA, Salama SM, Alwajeeh NS, Al Batran R, Ismail S, et al.
    Biomed Res Int, 2014;2014:792086.
    PMID: 24587992 DOI: 10.1155/2014/792086
    Wound healing involves inflammation followed by granular tissue development and scar formation. In this study, synthetic chalcone 3-(2-Chlorophenyl)-1-phenyl-propenone (CPPP) was investigated for a potential role in enhancing wound healing and closure. Twenty-four male rats were divided randomly into 4 groups: carboxymethyl cellulose (CMC) (0.2 mL), Intrasite gel, and CPPP (25 or 50 mg/mL). Gross morphology, wounds treatment with the CPPP, and Intrasite gel accelerate the rate of wound healing compared to CMC group. Ten days after surgery, the animals were sacrificed. Histological assessment revealed that the wounds treated with CPPP showed that wound closure site contained little amount of scar and the granulation tissue contained more collagen and less inflammatory cells than wound treated with CMC. This finding was confirmed with Masson's trichrome staining. The antioxidant defence enzymes catalase (CAT) and superoxide dismutase (SOD) were significantly increased in the wound homogenates treated with CPPP (P < 0.05) compared to CMC treated group. However, in the CPPP treatment group, lipid peroxidation (MDA) was significantly decreased (P < 0.05), suggesting that the CPPP also has an important role in protection against lipid peroxidation-induced skin injury after ten days of treatment with CPPP, which is similar to the values of cytokines TGF-β and TNF-α in tissue homogenate. Finally the administration of CPPP at a dosage of 25 and 50 mg/kg was suitable for the stimulation of wound healing.
    Matched MeSH terms: Collagen/metabolism
  10. Chua LS, Lee SY, Abdullah N, Sarmidi MR
    Fitoterapia, 2012 Dec;83(8):1322-35.
    PMID: 22521793 DOI: 10.1016/j.fitote.2012.04.002
    Labisia pumila is a traditional herb widely used as post-partum medication for centuries. Recently, extensive researches have been carried out on the phytochemical identification, biological and toxicological studies for the herb. Phytochemicals found in the herbal extract showed high antioxidant properties, which were essential for various pharmacological activities. The significant findings are anti-estrogenic deficiency and -immunodeficiency diseases. Another finding that has considerable impact on natural product research is the contribution of L. pumila in promoting skin collagen synthesis. The performance of the herb as anti-aging agent due to natural aging process and accelerated by UV radiation was reviewed critically.
    Matched MeSH terms: Collagen/biosynthesis*
  11. Sthaneshwar P, Chan SP
    Malays J Pathol, 2010 Jun;32(1):43-7.
    PMID: 20614725 MyJurnal
    Type IV collagen is the principal component of glomerular basement membrane and messangial matrix. Studies have shown increased levels of urinary type IV collagen (uIV) in diabetic patients compared to healthy controls. The concentration of uIV increases gradually as diabetic nephropathy progresses.
    AIM AND METHOD: This study was carried out to determine whether urinary type IV collagen (uIV) can serve as an indicator of diabetic nephropathy. Using a sandwich enzyme immunoassay technique, uIV excretion was determined in 30 type 2 diabetic patients with normoalbuminuria and 20 patients with microalbuminuria.
    RESULTS: uIV excretion was significantly increased in type 2 diabetics, in both normoalbuminuric and microalbuminuric patients, compared with healthy controls. The increase in urinary type IV collagen was well correlated with the amount of urinary albumin but not with HbA1C.
    CONCLUSION: Our findings that uIV is higher in those with microalbuminuria and correlates with albuminuria, support uIV as an indicator of diabetic nephropathy. Whether the increased uIV excretion would predict the impending renal failure needs further confirmation.
    Matched MeSH terms: Collagen Type IV/urine*
  12. Siar CH, Toh CG, Romanos G, Ng KH
    Clin Oral Implants Res, 2011 Jan;22(1):113-20.
    PMID: 20678135 DOI: 10.1111/j.1600-0501.2010.01970.x
    collagenous and noncollagenous membranes have been investigated in many animal systems but their effects in the macaque model are unknown.
    Matched MeSH terms: Collagen/metabolism
  13. Salin N, Ishak AK, Abdul Rahman S, Ali M, Nawawi HM, Said MS, et al.
    Med J Malaysia, 2008 Jul;63 Suppl A:67-8.
    PMID: 19024987
    Bone formation is an active process whereby osteoblasts are found on the surface of the newly formed bone. Adhesion to extracellular matrix is essential for the development of bone however not all surfaces are suitable for osteoblast adhesion and don't support osteoblastic functions. The objective of this study was to test the suitability of a collagen based microcarrier which would support osteoblastic functions.
    Matched MeSH terms: Collagen*
  14. Sasidaran R, Dorai AA, Sulaiman WA, Halim AS
    Med J Malaysia, 2008 Jul;63 Suppl A:29.
    PMID: 19024967
    We present our two year experience with a dermal regeneration template (INTEGRA) in burn reconstructive surgery for contracture release as well as a reconstructive tool for management of soft tissue loss.
    Matched MeSH terms: Collagen*
  15. Shetty S, Udupa S, Udupa L, Somayaji N
    Indian J. Physiol. Pharmacol., 2006 Apr-Jun;50(2):163-8.
    PMID: 17051736
    The present study was performed to evaluate the wound healing and antioxidant effect of aqueous extract of Ocimum sanctum Linn. (O. sanctum) in rats. Albino rats of either sex were divided into 2 groups. Group I: Wounded control rats; Group II: Wounded rats administered O. sanctum aqueous extract. Wound breaking strength in incision wound model, epithelization period and percent wound contraction in excision wound model were studied. Using dead space wound model, granulation tissue breaking strength, granulation tissue dry weight, hydoxyproline level in dry granulation tissue, superoxide dismutase (SOD) and catalase levels in wet granulation tissue were estimated in both the groups. Increased wound breaking strength, decreased epithelization period, increased percent wound contraction, increased granulation tissue weight and hydroxyproline concentrations were observed. The increased activity of antioxidant enzymes such as SOD, catalase level in extract treated group compared to controls. Granulation tissue was subjected to histopathological examination to determine the pattern of lay-down for collagen using Haematoxylin and Eosin stains which confirm the results. Owing to wound healing and antioxidant activities, O. sanctum may be useful in the management of abnormal healing such as keloids and hypertrophic scars.
    Matched MeSH terms: Collagen/metabolism
  16. Norazril SA, Aminuddin BS, Norhayati MM, Mazlyzam AL, Fauziah O, Ruszymah BH
    Med J Malaysia, 2004 May;59 Suppl B:186-7.
    PMID: 15468880
    Chitosan has similar structure to glycosaminoglycans in the tissue, thus may be a good candidates as tissue engineering scaffold. However, to improve their cell attachment ability, we try to incorporate this natural polymer with collagen by combining it via cross-linking process. In this preliminary study we evaluate the cell attachment ability of chitosan-collagen scaffold versus chitosan scaffold alone. Chitosan and collagen were dissolved in 1% acetic acid and then were frozen for 24 hours before the lyophilizing process. Human skin fibroblasts were seeded into both scaffold and were cultured in F12: DMEM (1:1). Metabolic activity assay were used to evaluate cell attachment ability of scaffold for a period of 1, 3, 7 and 14 days. Scanning electron micrographs shows good cell morphology on chitosan-collagen hybrid scaffold. In conclusion, the incorporation of collagen to chitosan will enhance its cell attachment ability and will be a potential scaffold in tissue engineering.
    Matched MeSH terms: Collagen*
  17. Annuar N, Spier RE
    Med J Malaysia, 2004 May;59 Suppl B:204-5.
    PMID: 15468889
    Selections of collagen available commercially were tested for their biocompatibility as scaffold to promote cell growth in vitro via simple collagen fast test and cultivation of mammalian cells on the selected type of collagen. It was found that collagen type C9791 promotes the highest degree of aggregation as well as cells growth. This preliminary study also indicated potential use of collagen as scaffold in engineered tissue.
    Matched MeSH terms: Collagen*
  18. Norhayati MM, Mazlyzam AL, Asmah R, Fuzina H, Aminuddin BS, Ruszymah BH, et al.
    Med J Malaysia, 2004 May;59 Suppl B:184-5.
    PMID: 15468879
    Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) evaluation were carried out in the in vivo skin construct using fibrin as biomaterial. To investigate its progressive remodeling, nude mice were grafted and the Extracellular Matrix (ECM) components were studied at four and eight weeks post-grafting. It was discovered that by 4 weeks of remodeling the skin construct acquired its native structure.
    Matched MeSH terms: Collagen/physiology*
  19. Tan KK, Aminuddin BS, Tan GH, Sabarul Afian M, Ng MH, Fauziah O, et al.
    Med J Malaysia, 2004 May;59 Suppl B:43-4.
    PMID: 15468810
    The strategy used to generate tissue-engineered bone construct, in view of future clinical application is presented here. Osteoprogenitor cells from periosteum of consenting scoliosis patients were isolated. Growth factors viz TGF-B2, bFGF and IGF-1 were used in concert to increase cell proliferation during in vitro cell expansion. Porous tricalcium phosphate (TCP)-hydroxyapatite (HA) scaffold was used as the scaffold to form 3D bone construct. We found that the addition of growth factors, greatly increased cell growth by 2 to 7 fold. TCP/HA proved to be the ideal scaffold for cell attachment and proliferation. Hence, this model will be further carried out on animal trial.
    Matched MeSH terms: Collagen/metabolism
  20. Ismarul IN, Ishak Y, Ismail Z, Mohd Shalihuddin WM
    Med J Malaysia, 2004 May;59 Suppl B:57-8.
    PMID: 15468817
    Various proportions of chitosan/collagen films (70/30% to 95/05%) w/w were prepared and evaluated for its suitability as skin regenerating scaffold. Interactions between chitosan and collagen were studied using Fourier Transform Infrared spectroscopy (FTIR) and Differential Scanning Colorimetry (DSC). Scanning Electron Microscope (SEM) was used to investigate the morphology of the blend. Mechanical properties were evaluated using a Universal Testing Machine (UTM). The chitosan/collagen films were found to swell proportionally with time until it reaches equilibrium. FTIR spectroscopy indicated no chemical interaction between the components of the blends. DSC data indicated only one peak proving that these two materials are compatible at all proportions investigated. SEM micrographs also indicated good homogeneity between these two materials.
    Matched MeSH terms: Collagen Type I/analysis*
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