Displaying publications 21 - 40 of 277 in total

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  1. Effects of ranibizumab on the extracellular matrix production by human Tenon's fibroblast
    Md Noh SM, Sheikh Abdul Kadir SH, Bannur ZM, Froemming GA, Abdul Hamid Hasani N, Mohd Nawawi H, et al.
    Exp Eye Res, 2014 Oct;127:236-42.
    PMID: 25139730 DOI: 10.1016/j.exer.2014.08.005
    Anti-Vascular Endothelial Growth Factors (Anti-VEGF) agents have received recent interest as potential anti-fibrotic agents for their concurrent use with trabeculectomy. Preliminary cohort studies have revealed improved bleb morphology following trabeculectomy augmented with ranibizumab. The effects of this humanized monoclonal antibody on human Tenon's fibroblast (HTF), the key player of post trabeculectomy scar formation, are not fully understood. This study was conducted to understand the effects of ranibizumab on extracellular matrix production by HTF. The effect of ranibizumab on HTF proliferation and cell viability was determined using MTT assay (3-(4,5-dimethylthiazone-2-yl)-2,5-diphenyl tetrazolium). Ranibizumab at concentrations ranging from 0.01 to 0.5 mg/mL were administered for 24, 48 and 72 h in serum and serum free conditions. Supernatants and cell lysates from samples were assessed for collagen type 1 alpha 1 and fibronectin mRNA and protein level using quantitative real time polymerase chain reaction (qRT-PCR) and enzyme-linked immunosorbent assay (ELISA). After 48-h, ranibizumab at 0.5 mg/mL, significantly induced cell death under serum-free culture conditions (p collagen type 1 alpha 1 (COL1A1) mRNA, but not for fibronectin (FN). Meanwhile, COL1A1 and FN protein levels were found upregulated in treated monolayers compared to control monolayers. Ranibizumab at 0.5 mg/mL significantly reduced cell viability in cultured HTF. From this study, we found that single application of ranibizumab is inadequate to induce the anti-fibrotic effects on HTF, suggesting the importance of adjunctive therapy. Further studies are underway to understand mechanism of actions of ranibizumab on HTF.
    Matched MeSH terms: Collagen Type I/genetics*; Collagen Type I/metabolism
  2. Fulltext Mechanisms underpinning the permanent muscle damage induced by snake venom metalloprotease
    Williams HF, Mellows BA, Mitchell R, Sfyri P, Layfield HJ, Salamah M, et al.
    PLoS Negl Trop Dis, 2019 01;13(1):e0007041.
    PMID: 30695027 DOI: 10.1371/journal.pntd.0007041
    Snakebite is a major neglected tropical health issue that affects over 5 million people worldwide resulting in around 1.8 million envenomations and 100,000 deaths each year. Snakebite envenomation also causes innumerable morbidities, specifically loss of limbs as a result of excessive tissue/muscle damage. Snake venom metalloproteases (SVMPs) are a predominant component of viper venoms, and are involved in the degradation of basement membrane proteins (particularly collagen) surrounding the tissues around the bite site. Although their collagenolytic properties have been established, the molecular mechanisms through which SVMPs induce permanent muscle damage are poorly understood. Here, we demonstrate the purification and characterisation of an SVMP from a viper (Crotalus atrox) venom. Mass spectrometry analysis confirmed that this protein is most likely to be a group III metalloprotease (showing high similarity to VAP2A) and has been referred to as CAMP (Crotalus atrox metalloprotease). CAMP displays both collagenolytic and fibrinogenolytic activities and inhibits CRP-XL-induced platelet aggregation. To determine its effects on muscle damage, CAMP was administered into the tibialis anterior muscle of mice and its actions were compared with cardiotoxin I (a three-finger toxin) from an elapid snake (Naja pallida) venom. Extensive immunohistochemistry analyses revealed that CAMP significantly damages skeletal muscles by attacking the collagen scaffold and other important basement membrane proteins, and prevents their regeneration through disrupting the functions of satellite cells. In contrast, cardiotoxin I destroys skeletal muscle by damaging the plasma membrane, but does not impact regeneration due to its inability to affect the extracellular matrix. Overall, this study provides novel insights into the mechanisms through which SVMPs induce permanent muscle damage.
    Matched MeSH terms: Collagen
  3. Fulltext The immunohistochemical and urodynamic evaluation towards the collagen-coated and non-coated polypropylene meshes implanted in the pelvic wall of the rats
    Lo TS, Lin YH, Yusoff FM, Chu HC, Hsieh WC, Uy-Patrimonio MC
    Sci Rep, 2016 12 19;6:38960.
    PMID: 27991501 DOI: 10.1038/srep38960
    Our aim is to study the inflammatory response towards the collagen-coated and non-coated polypropylene meshes in rats and the urodynamic investigation post-operatively. Forty-two female Sprague Dawley were divided into 7 groups of 6 rats; Control, Day 7 and 30 for Sham, Avaulta Plus (MPC), Perigee (MP). UDS were taken at days 7 and 30. Mesh with the vagina and bladder wall was removed and sent for immunohistochemical examination. Results showed intense inflammatory reaction on day 7 in the study groups which decreased on day 30. IL-1, TNF-α, MMP-2 and CD31 were observed to decrease from day 7 to day 30. NGF was almost normal on day 30 in all groups. UDS showed no difference in voiding pressure. Both Study and Sham groups had shorter voiding interval (VI) on day 7 but significantly lower in MPC. VI had significantly increased on day 30 in all groups. Voided volume was significantly lower in the mesh groups even when an increase was seen on day 30. In conclusion, the higher levels of IL-1, TNF-α and MMP-2 in collagen-coated polypropylene mesh imply greater inflammation than the non-coated polypropylene mesh. Mesh implantation can lead to shorter voiding interval and smaller bladder capacity.
    Matched MeSH terms: Collagen*
  4. The mechanisms of fibroblast-mediated compaction of collagen gels and the mechanical niche around individual fibroblasts
    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*
  5. A fibril-based structural constitutive theory reveals the dominant role of network characteristics on the mechanical behavior of fibroblast-compacted collagen gels
    Feng Z, Ishiguro Y, Fujita K, Kosawada T, Nakamura T, Sato D, et al.
    Biomaterials, 2015 Oct;67:365-81.
    PMID: 26247391 DOI: 10.1016/j.biomaterials.2015.07.038
    In this paper, we present a general, fibril-based structural constitutive theory which accounts for three material aspects of crosslinked filamentous materials: the single fibrillar force response, the fibrillar network model, and the effects of alterations to the fibrillar network. In the case of the single fibrillar response, we develop a formula that covers the entropic and enthalpic deformation regions, and introduce the relaxation phase to explain the observed force decay after crosslink breakage. For the filamentous network model, we characterize the constituent element of the fibrillar network in terms its end-to-end distance vector and its contour length, then decompose the vector orientation into an isotropic random term and a specific alignment, paving the way for an expanded formalism from principal deformation to general 3D deformation; and, more important, we define a critical core quantity over which macroscale mechanical characteristics can be integrated: the ratio of the initial end-to-end distance to the contour length (and its probability function). For network alterations, we quantitatively treat changes in constituent elements and relate these changes to the alteration of network characteristics. Singular in its physical rigor and clarity, this constitutive theory can reproduce and predict a wide range of nonlinear mechanical behavior in materials composed of a crosslinked filamentous network, including: stress relaxation (with dual relaxation coefficients as typically observed in soft tissues); hysteresis with decreasing maximum stress under serial cyclic loading; strain-stiffening under uniaxial tension; the rupture point of the structure as a whole; various effects of biaxial tensile loading; strain-stiffening under simple shearing; the so-called "negative normal stress" phenomenon; and enthalpic elastic behaviors of the constituent element. Applied to compacted collagen gels, the theory demonstrates that collagen fibrils behave as enthalpic elasticas with linear elasticity within the gels, and that the macroscale nonlinearity of the gels originates from the curved fibrillar network. Meanwhile, the underlying factors that determine the mechanical properties of the gels are clarified. Finally, the implications of this study on the enhancement of the mechanical properties of compacted collagen gels and on the cellular mechanics with this model tissue are discussed.
    Matched MeSH terms: Collagen/pharmacology*
  6. Xeno-free and feeder-free culture and differentiation of human embryonic stem cells on recombinant vitronectin-grafted hydrogels
    Chen LH, Sung TC, Lee HH, Higuchi A, Su HC, Lin KJ, et al.
    Biomater Sci, 2019 Aug 14.
    PMID: 31411209 DOI: 10.1039/c9bm00418a
    Recombinant vitronectin-grafted hydrogels were developed by adjusting surface charge of the hydrogels with grafting of poly-l-lysine for optimal culture of human embryonic stem cells (hESCs) under xeno- and feeder-free culture conditions, with elasticity regulated by crosslinking time (10-30 kPa), in contrast to conventional recombinant vitronectin coating dishes, which have a fixed stiff surface (3 GPa). hESCs proliferated on the hydrogels for over 10 passages and differentiated into the cells derived from three germ layers indicating the maintenance of pluripotency. hESCs on the hydrogels differentiated into cardiomyocytes under xeno-free culture conditions with much higher efficiency (80% of cTnT+ cells) than those on conventional recombinant vitronectin or Matrigel-coating dishes just only after 12 days of induction. It is important to have an optimal design of cell culture biomaterials where biological cues (recombinant vitronectin) and physical cues (optimal elasticity) are combined for high differentiation of hESCs into specific cell lineages, such as cardiomyocytes, under xeno-free and feeder-free culture conditions.
    Matched MeSH terms: Collagen
  7. Congenital myasthenic syndrome with novel pathogenic variants in the COLQ gene associated with the presence of antibodies to acetylcholine receptors
    Tay CG, Fong CY, Li L, Ganesan V, Teh CM, Gan CS, et al.
    J Clin Neurosci, 2020 Feb;72:468-471.
    PMID: 31831253 DOI: 10.1016/j.jocn.2019.12.007
    Congenital myasthenic syndrome (CMS) is a heterogeneous group of inherited disorder which does not associate with anti-acetylcholine receptor (AChR) antibody. The presence of AChR autoantibody is pathogenic and highly sensitive and specific for autoimmune myasthenia gravis (MG). We describe 2 children from unrelated families who presented with hypotonia, ptosis and fatigability in early infancy with anti-AChR antibodies detected via ELISA on 2 separate occasions in the sera. Both were treated as refractory autoimmune MG due to poor clinical response to acetylcholinesterase inhibitor and immunotherapy. In view of the atypical clinical features, genetic studies of CMS were performed and both were confirmed to have novel pathogenic mutations in the COLQ gene. To the best of our knowledge, the presence of anti-AChR antibody in COLQ-related CMS has never been reported in the literature. The clinical presentation of early onset phenotype, and refractoriness to acetylcholinesterase inhibitor and immunotherapy should prompt CMS as a differential diagnosis.
    Matched MeSH terms: Collagen/genetics*; Collagen/therapeutic use
  8. A hyperelastic fibre-reinforced continuum model of healing tendons with distributed collagen fibre orientations
    Bajuri MN, Isaksson H, Eliasson P, Thompson MS
    Biomech Model Mechanobiol, 2016 12;15(6):1457-1466.
    PMID: 26951049
    The healing process of ruptured tendons is problematic due to scar tissue formation and deteriorated material properties, and in some cases, it may take nearly a year to complete. Mechanical loading has been shown to positively influence tendon healing; however, the mechanisms remain unclear. Computational mechanobiology methods employed extensively to model bone healing have achieved high fidelity. This study aimed to investigate whether an established hyperelastic fibre-reinforced continuum model introduced by Gasser, Ogden and Holzapfel (GOH) can be used to capture the mechanical behaviour of the Achilles tendon under loading during discrete timepoints of the healing process and to assess the model's sensitivity to its microstructural parameters. Curve fitting of the GOH model against experimental tensile testing data of rat Achilles tendons at four timepoints during the tendon repair was used and achieved excellent fits ([Formula: see text]). A parametric sensitivity study using a three-level central composite design, which is a fractional factorial design method, showed that the collagen-fibre-related parameters in the GOH model-[Formula: see text] and [Formula: see text]-had almost equal influence on the fitting. This study demonstrates that the GOH hyperelastic fibre-reinforced model is capable of describing the mechanical behaviour of healing tendons and that further experiments should focus on establishing the structural and material parameters of collagen fibres in the healing tissue.
    Matched MeSH terms: Collagen/chemistry*
  9. Fulltext Collagen type I promotes osteogenic differentiation of amniotic membrane-derived mesenchymal stromal cells in basal and induction media
    Akhir HM, Teoh PL
    Biosci Rep, 2020 12 23;40(12).
    PMID: 33245097 DOI: 10.1042/BSR20201325
    Collagen has been widely shown to promote osteogenesis of bone marrow mesenchymal stromal cells (BM-MSCs). Due to the invasive procedure of obtaining BM-MSCs, MSCs from other tissues have emerged as a promising alternative for regenerative therapy. MSCs originated from different sources, exhibiting different differentiation potentials. Therefore, the applicability of collagen type I (COL), combining with amniotic membrane (AM)-MSCs was examined through proliferation and differentiation assays together with the expression of surface markers and genes associated with stemness and differentiation under basal or induction conditions. No increase in cell growth was observed because AM-MSCs might be directed toward spontaneous osteogenesis. This was evidenced by the calcium deposition and elevated expression of osteogenic genes when AM-MSCs were cultured in collagen plate with basal media. Under the osteogenic condition, reciprocal expression of OCN and CEBPA suggested a shift toward adipogenesis. Surprisingly, adipogenic genes were not elevated upon adipogenic induction, although oil droplets deposition was observed. In conclusion, our findings demonstrated that collagen causes spontaneous osteogenesis in AM-MSCs. However, the presence of exogenous inductors could shift the direction of adipo-osteogenic gene regulatory network modulated by collagen.
    Matched MeSH terms: Collagen Type I/pharmacology*
  10. Fulltext Does chlorella vulgaris modulate the expression of col and mmp genes in skin ageing?
    Loke, C.Y., Nur Hidayah, M.S., Mohd Fadhli, M.F., Teo, SK, Nor Hidayah, A.G., Yasmin Anum, M.Y., et al.
    Medicine & Health, 2010;5(1):1-12.
    MyJurnal
    Chlorella vulgaris, a unicellular microalgae, produces many intracellular phytochemicals namely carotenoids, tocopherols, ubiquinone and protein. Skin ageing which is induced by oxidative stress involves decreased extracellular matrix synthesis and increased expression of enzymes that degrade the collagenous matrix. The objective of this study was to determine the effect of C. vulgaris on the expression of genes encoded for collagen (COL) and matrix metalloproteinases (MMPs) which are involved in skin ageing. Human diploid fibroblasts (HDFs) were obtained from circumcision foreskin of 8-12 year-old boys. HDFs were cultured into 3 groups: untreated control cells, cells with stress-induced premature senescence (SIPS; cells were induced with H2O2 at passage 6 for 2 weeks) and SIPS treated with C. vulgaris (prolonged C. vulgaris treatment started at passage 4 and combined treatment with H2O2 at passage 6 for 2 weeks). Senescence-associated ß-galactosidase (SA ß-gal) was determined using senescent cells histochemical staining kit (Sigma, USA). Expression of COLI, COLIII, COLIV, MMPI, MMPII and MMPIII genes was quantitatively analysed with real-time RT-PCR method (iScript™ One Step real-time PCR with SYBR® Green; Biorad). HDFs treated with H2O2 (SIPS) exhibited senescent morphological features of flattening and enlarged with increased expression of SA ß-gal (p
    Matched MeSH terms: Collagen
  11. Fulltext Encapsulation and Characterization of Gentamicin Sulfate in the Collagen Added Electrospun Nanofibers for Skin Regeneration
    Abdul Khodir WKW, Abdul Razak AH, Ng MH, Guarino V, Susanti D
    J Funct Biomater, 2018 May 18;9(2).
    PMID: 29783681 DOI: 10.3390/jfb9020036
    In the current practice, the clinical use of conventional skin substitutes such as autogenous skin grafts have shown several problems, mainly with respect to limited sources and donor site morbidity. In order to overcome these limitations, the use of smart synthetic biomaterials is tremendously diffusing as skin substitutes. Indeed, engineered skin grafts or analogues frequently play an important role in the treatment of chronic skin wounds, by supporting the regeneration of newly formed tissue, and at the same time preventing infections during the long-term treatment. In this context, natural proteins such as collagen-natively present in the skin tissue-embedded in synthetic polymers (i.e., PCL) allow the development of micro-structured matrices able to mimic the functions and to structure of the surrounding extracellular matrix. Moreover, the encapsulation of drugs, such as gentamicin sulfate, also improves the bioactivity of nanofibers, due to the efficient loading and a controlled drug release towards the site of interest. Herein, we have done a preliminary investigation on the capability of gentamicin sulfate, loaded into collagen-added nanofibers, for the controlled release in local infection treatments. Experimental studies have demonstrated that collagen added fibers can be efficaciously used to administrate gentamicin for 72 h without any toxic in vitro response, thus emerging as a valid candidate for the therapeutic treatment of infected wounds.
    Matched MeSH terms: Collagen
  12. Andrographolide prevented toluene diisocyanate-induced occupational asthma and aberrant airway E-cadherin distribution via p38 MAPK-dependent Nrf2 induction
    Sulaiman I, Tan K, Mohtarrudin N, Lim JCW, Stanslas J
    Pulm Pharmacol Ther, 2018 12;53:39-51.
    PMID: 30244166 DOI: 10.1016/j.pupt.2018.09.008
    Toluene diisocyanate (TDI) is a major cause of chemical-induced occupational asthma, which contributes about 15% of global asthma burden. Resistance and compounded side effects associated with the use of corticosteroid in asthma necessitate the search for alternative drugs. Andrographolide (AGP), a naturally occurring diterpene lactone is known to exhibit various bioactivities. Its ability to ameliorate cardinal features of allergic asthma was previously suggested in an eosinophilic asthma endotype. However, its potential antiasthma activity and mechanism of action in a neutrophilic occupational asthma model, as well as its effect on epithelial dysfunction remain unknown. BALB/c mice were dermally sensitised with 0.3% TDI or acetone olive oil (AOO) vehicle on day 1 and 8, followed by 0.1% TDI intranasal challenge on days 15, 18 and 21. Endpoints were evaluated via bronchoalveolar lavage fluid (BALF) cell analysis, 2',7'-dichlorofluorescein diacetate (DCFDA) assays, immunoblotting, immunohistochemistry and methacholine challenge test. Decreases in total and differential leukocyte counts of BALF were recorded in AGP-treated animals. The compound dose-dependently reduced intracellular de-esterification of DCFDA, thus suggesting AGP's potential to inhibit intracellular reactive oxygen species (ROS). Mechanistically, the treatment prevented TDI-induced aberrant E-cadherin distribution and restored airway epithelial β-catenin at cell to cell contact site. Furthermore, AGP ameliorated TDI induced pulmonary collagen deposition. In addition, the treatment significantly upregulated pulmonary HO-1, Nrf2 and phospho-p38 levels. Airway hyperresponsiveness was markedly suppressed among AGP-treated animals. Collectively, these findings suggest AGP's protective function against TDI-induced airway epithelial barrier dysfunction and oxidative lung damage possibly through the upregulation of adherence junction proteins and the activation of p38/Nrf2 signalling. This study elucidates the therapeutic potential of AGP in the control and management of chemical-induced allergic asthma. To the best of our knowledge, the potential anti-asthma activity of AGP in TDI-induced occupational asthma has not been reported previously.
    Matched MeSH terms: Collagen/metabolism
  13. Collagen as potential cell scaffolds for tissue engineering
    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*
  14. Wound healing activity of Ocimum sanctum Linn with supportive role of antioxidant enzymes
    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
  15. Fulltext Structural changes in the urinary bladder of streptozotocin-induced diabetic rats and the possible protective role of insulin
    Elnagar, Amir M. Bassam, Suhaidah Ibrahim, Abouelnaga, Mostafa A.M., Soliman, Amro Mohamed
    International Medical Journal Malaysia, 2018;17(3):39-48.
    MyJurnal
    Introduction: Diabetes mellitus possesses severe adverse effects on the urinary bladder. Urinary bladder dysfunction is a common health problem affecting diabetic patients causing recurrent infections and urinary incontinence. Objective: To evaluate the histopathological changes in the tissue of urinary bladder in Streptozotocin (STZ) diabetic rats and the protective role of insulin. Methods: Thirty rats were classified into three groups: a control group which received no treatment (Group A), STZ diabetic group (Group B) and Insulin diabetic group (Group C). Animals were sacrificed after six weeks and urinary bladders were harvested and processed for light and electron microscopy. Results: Several histopathological changes were observed in the urinary bladder of the diabetic group including an increase in the thickness of the urothelium, epithelial cells with dark nuclei and large lenticular vesicles, and wide intercellular spaces with numerous collagen fibers. Treatment with insulin reduced the pathological changes induced by STZ. Conclusion: Diabetes mellitus caused significant pathological changes in the urinary bladder of experimental rats. For instance, treating diabetic animals with insulin prevented the development of damaging effects of diabetes on the urinary bladder.
    Matched MeSH terms: Collagen
  16. The anti-osteoporotic effect of Eurycoma Longifolia in aged orchidectomised rat model
    Shuid AN, Abu Bakar MF, Abdul Shukor TA, Muhammad N, Mohamed N, Soelaiman IN
    Aging Male, 2011 Sep;14(3):150-4.
    PMID: 20874437 DOI: 10.3109/13685538.2010.511327
    Osteoporosis in elderly men is becoming an important health issue with the aging society. Elderly men with androgen deficiency are exposed to osteoporosis and can be treated with testosterone replacement. In this study, Eurycoma longifolia (EL), a plant with androgenic effects, was supplemented to an androgen-deficient osteoporotic aged rat as alternative to testosterone. Aged 12 months old Sprague-Dawley rats were divided into groups of normal control (NC), sham-operated (SO), orchidectomised-control (OrxC), orchidectomised and supplemented with EL (Orx + El) and orchidectomised and given testosterone (Orx + T). After 6 weeks of treatment, serum osteocalcin, serum terminal C-telopeptide Type 1 collagen (CTX) and the fourth lumbar bone calcium were measured. There were no significant differences in the osteocalcin levels before and after treatment in all the groups. The CTX levels were also similar for all the groups before treatment. However, after treatment, orchidectomy had caused significant elevation of CTX compared to normal control rats. Testosterone replacements in orchidectomised rats were able to prevent the rise of CTX. Orchidectomy had also reduced the bone calcium level compared to normal control rats. Both testosterone replacement and EL supplementation to orchidectomised rats were able to maintain the bone calcium level, with the former showing better effects. As a conclusion, EL prevented bone calcium loss in orchidectomised rats and therefore has the potential to be used as an alternative treatment for androgen deficient osteoporosis.
    Matched MeSH terms: Collagen Type I/blood
  17. Desmoplastic variant of ameloblastoma in Malaysians
    Ng KH, Siar CH
    Br J Oral Maxillofac Surg, 1993 Oct;31(5):299-303.
    PMID: 8218083
    Seventeen cases are reported of desmoplastic variant of ameloblastoma of the jaws observed during the years 1967-1991. There were 12 females and 5 males, and these consisted of 7 Chinese, 6 Malays, 2 Indians, 1 Sikh and 1 Kadazan. Their ages at diagnosis ranged from 21-60 years with a mean of 36.6 years. There were 10 mandibular and 7 maxillary tumours. Of these, 14 cases involved the anterior segment with extension to the premolar region in 5 cases. 60% of cases were radiologically suggestive of fibro-osseous lesions. The main mode of treatment was resection and 1 case presented with recurrence. The findings of this study were compared with those of previous reports.
    Matched MeSH terms: Collagen
  18. Scale morphologies of freshwater fishes at Tembat Forest Reserve, Terengganu, Malaysia
    Farah Ayuni Farinordin, Wan Seribani Wan Nilam, Shahril Mod Husin, Abdullah Samat, Shukor Md. Nor
    Sains Malaysiana, 2017;46:1429-1439.
    Scales are calcium carbonate and collagen-contained structures embedded within the fish epidermis and useful for
    species identification. This study aimed to describe morphological characteristics of scales and use the differences to
    prepare keys to species. Fishes were sampled from selected rivers of Tembat Forest Reserve, Hulu Terengganu. Specimens
    caught were from 3 families (Cyprinidae, Channidae, Nandidae) and 17 species. Each species was represented by ten
    individuals (size ranges 2.5 - 50 cm TL). The scales were removed, soaked in H2
    O2
    (0.5%), NH3 (0.3%), DH2
    O and
    mounted between a pair of glass slides for digital photographing. The morphological descriptions were based on types
    of scales, distinctiveness of radii arrangement at the anterior field, radii cover, radii distribution, overall shape, focus
    position and focus pattern. Keys to species were constructed based on these scale morphological characters described.
    Measurements of scale total length (L), total width (W), rostral field length (L1) and caudal field length (L2) of the scales
    were taken using Image J software. The inter-specific variation among scales was indicated by L1/L, L2/L, L1/L2 and
    W/L indices through multiple comparison tests (ANOVA). It was found that all 17 species showed significant differences
    with at least one other species in all four indices. Pristolepis grootii (Bleeker 1852) was the only one that significantly
    different (p<0.05) from other 16 species in the first three indices. Species that showed the least significant differences
    among species was Probarbus jullieni (Sauvage 1880). The differences among the scales were primarily due to the
    different types of scale that was either ctenoid or cycloid.
    Matched MeSH terms: Collagen
  19. Eurycoma longifolia as a potential alternative to testosterone for the treatment of osteoporosis: Exploring time-mannered proliferative, differentiative and morphogenic modulation in osteoblasts
    Thu HE, Mohamed IN, Hussain Z, Shuid AN
    J Ethnopharmacol, 2017 Jan 04;195:143-158.
    PMID: 27818256 DOI: 10.1016/j.jep.2016.10.085
    ETHNOPHARMACOLOGICAL RELEVANCE: Eurycoma longifolia (EL) has been well-studied traditionally as a chief ingredient of many polyherbal formulations for the management of male osteoporosis. It has also been well-recognised to protect against bone calcium loss in orchidectomised rats.

    AIM OF THE STUDY: To evaluate the effects of EL on the time-mannered sequential proliferative, differentiative, and morphogenic modulation in osteoblasts compared with testosterone.

    MATERIALS AND METHODS: Cell proliferation was analysed using MTS assay and phase contrast microscopy. Osteogenic differentiation of MC3T3-E1 cells was assessed through a series of characteristic assays which include crystal violet staining, alkaline phosphatase (ALP) activity and Van Gieson staining. Taken together, the bone mineralization of extra cellular matrix (ECM) was estimated using alizarin red s (ARS) staining, von kossa staining, scanning electron microscopic (SEM) and energy dispersive x-ray (EDX) analysis.

    RESULTS: The cell proliferation data clearly revealed the efficiency of EL particularly at a dose of 25µg/mL, in improving the growth of MC3T3-E1 cells compared with the untreated cells. Data also showed the prominence of EL in significantly promoting ALP activity throughout the entire duration of treatment compared with the testosterone-treated cells. The osteogenic differentiation potential of EL was further explored by analysing mineralization data which revealed that the calcified nodule formation (calcium deposition) and phosphate deposition was more pronounced in cells treated with 25µg/mL concentration of EL at various time points compared with the untreated and testosterone treated cells. The scanning electron microscopic (SEM) analysis also revealed highest globular masses of mineral deposits (identified as white colour crystals) in the ECM of cultured cells treated with 25µg/mL concentration of EL.

    CONCLUSION: Compared to testosterone, greater potential of EL in promoting the proliferation and osteogenic differentiation of MC3T3-E1 cells provides an in vitro basis for the prevention of male osteoporosis. Thus, we anticipate that EL can be considered as an alternative approach to testosterone replacement therapy (TRT) for the treatment of male osteoporosis.

    Matched MeSH terms: Collagen/metabolism
  20. Fulltext Demethylbelamcandaquinone B (Dmcq B) Is the Active Compound of Marantodes pumilum var. alata (Blume) Kuntze with Osteoanabolic Activities
    Ahmad Hairi H, Jamal JA, Aladdin NA, Husain K, Mohd Sofi NS, Mohamed N, et al.
    Molecules, 2018 Jul 11;23(7).
    PMID: 29997309 DOI: 10.3390/molecules23071686
    Phytoestrogens have attracted considerable attention for their potential in the prevention of postmenopausal osteoporosis. Recently, a phytoestrogen-rich herbal plant, Marantodes pumilum var. alata (Blume) Kuntze was reported to protect against bone loss in ovariectomized rat. However, the bioactive compound responsible for these effects and the underlying mechanism were not known. Through bioassay-guided isolation, demethylbelamcandaquinone B (Dmcq B) was isolated and identified from Marantodes pumilum var. alata leaf extract. In terms of its bone anabolic effects, Dmcq B was at par with 17β-estradiol (E2), in promoting the proliferation, differentiation and mineralization of osteoblast cells. Dmcq-B increased early differentiation markers, collagen content and enzymatic ALP activity. It was demonstrated to regulate BMP2 signaling pathway which further activated the transcription factor, osterix. Subsequently, Dmcq B was able to increase the osteocalcin expression which promoted matrix mineralization as evidenced by the increase in calcium deposition. Dmcq B also reduced the protein level of receptor activator of NF-κβ ligand (RANKL) and promoted osteoprotegerin (OPG) protein expression by osteoblast cells, therefore hastening bone formation rate by decreasing RANKL/OPG ratio. Moreover, Dmcq B was able to increase ER expression, postulating its phytoestrogen property. As the conclusion, Dmcq B is the active compound isolated from Marantodes pumilum var. alata leaves, regulating osteoanabolic activities potentially through the BMP2 and ER signaling pathways.
    Matched MeSH terms: Collagen/metabolism
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