Collagen
From Wikipedia, the free encyclopedia
Collagen is a group of naturally occurring proteins is the main component of connective tissue and is the most abundant protein making up about 25% to 35% of the whole-body protein content. Collagen, in the form of elongated fibrils, is mostly found in fibrous tissues such as tendon, ligament and skin, and is also abundant in cornea, cartilage, bone, blood vessels, the gut, and intervertebral disc. The fibroblast is the most common cell which creates collagen. In muscle tissue, it serves as a major component of the endomysium. Collagen constitutes one to two percent of muscle tissue, and accounts for 6% of the weight of strong, tendinous muscles.[3] Gelatin, which is used in food and industry, is collagen that has been irreversibly hydrolyzed.
Types and associated disorders
Collagen occurs in many places throughout the body. Over 90% of the collagen in the body, however, is of type I.[37]
So far, 28 types of collagen have been identified and described. The five most common types are:
Collagen I: skin, tendon, vascular ligature, organs, bone (main component of the organic part of bone)
Collagen II: cartilage (main component of cartilage)
Collagen III: reticulate (main component of reticular fibers), commonly found alongside type I.
Collagen IV: forms bases of cell basement membrane
Collagen V: cell surfaces, hair and placenta
Collagen-related diseases most commonly arise from genetic defects or nutritional deficiencies that affect the biosynthesis, assembly, postranslational modification, secretion, or other processes involved in normal collagen production.
Genetic Defects of Collagen Genes
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
–
|
In addition to the above mentioned disorders, excessive deposition of collagen occurs in scleroderma.
Diseases [edit]
One thousand mutations have been identified in twelve out of more than twenty types of collagen. These mutations can lead to various diseases at the tissue level.[39]
Osteogenesis imperfecta – Caused by a mutation in type 1 collagen, dominant autosomal disorder, results in weak bones and irregular connective tissue, some cases can be mild while others can be lethal, mild cases have lowered levels of collagen type 1 while severe cases have structural defects in collagen.[40]
Chondrodysplasias – Skeletal disorder believed to be caused by a mutation in type 2 collagen, further research is being conducted to confirm this.[41]
Ehler-Danlos Syndrome – Ten different types of this disorder which lead to deformities in connective tissue, some types can be lethal that lead to the rupture of arteries, each syndrome is caused by a different mutation, for example type four of this disorder is caused by a mutation in collagen type 3.[42]
Alport syndrome – Can be passed on genetically, both an autosomal dominant and autosomal recessive disorder, sufferers have problems with their kidneys and eyes, loss of hearing can also develop in during the childhood or adolescent years.[43]
Osteoporosis – Not inherited genetically, brought on with age, associated with reduced levels of collagen in the skin and bones, growth hormone injections are being researched as a possible treatment to counteract any loss of collagen.[44]
Knobloch syndrome – Caused by a mutation in the collagen XVIII gene, patients present with protrusion of the brain tissue and degeneration of the retina, an individual who has family members suffering from the disorder are at an increased risk of developing it themselves as there is a hereditary link.[39]
Characteristics [edit]
Collagen is one of the long, fibrous structural proteins whose functions are quite different from those of globular proteinssuch as enzymes. Tough bundles of collagen called collagen fibers are a major component of the extracellular matrix that supports most tissues and gives cells structure from the outside, but collagen is also found inside certain cells. Collagen has great tensile strength, and is the main component of fascia, cartilage, ligaments, tendons, bone and skin.[45][46] Along with soft keratin, it is responsible for skin strength and elasticity, and its degradation leads to wrinkles that accompanyaging.[47][48] It strengthens blood vessels and plays a role in tissue development. It is present in the cornea and lens of the eye in crystalline form.
Some Uses of Collagen in our World
Collagen has a wide variety of applications, from food to medical. For instance, it is used in cosmetic surgery and burns surgery. It is widely used in the form of collagen casings for sausages.
If collagen is sufficiently denatured, e.g. by heating, the three tropocollagen strands separate partially or completely into globular domains, containing a different secondary structure to the normal collagen polyproline II (PPII), e.g. random coils. This process describes the formation of gelatin, which is used in many foods, including flavored gelatin desserts. Besides food, gelatin has been used in pharmaceutical, cosmetic, and photography industries.[49] From a nutritional point of view, collagen and gelatin are a poor-quality sole source of protein since they do not contain all the essential amino acids in the proportions that the human body requires—they are not 'complete proteins' (as defined by food science, not that they are partially structured). Manufacturers of collagen-based dietary supplements claim that their products can improve skin and fingernail quality as well as joint health. However, mainstream scientific research has not shown strong evidence to support these claims.[citation needed] Individuals with problems in these areas are more likely to be suffering from some other underlying condition (such as normal aging, dry skin, arthritis etc.) rather than just a protein deficiency.
From the Greek for glue, kolla, the word collagen means "glue producer" and refers to the early process of boiling the skin and sinews of horses and other animals to obtain glue. Collagen adhesive was used by Egyptians about 4,000 years ago, and Native Americans used it in bows about 1,500 years ago. The oldest glue in the world, carbon-dated as more than 8,000 years old, was found to be collagen—used as a protective lining on rope baskets and embroidered fabrics, and to hold utensils together; also in crisscross decorations on human skulls.[50] Collagen normally converts to gelatin, but survived due to the dry conditions. Animal glues are thermoplastic, softening again upon reheating, and so they are still used in making musical instruments such as fine violins and guitars, which may have to be reopened for repairs—an application incompatible with tough, synthetic plastic adhesives, which are permanent. Animal sinews and skins, including leather, have been used to make useful articles for millennia.
Cardiac applications
The four dense collagen valve rings, the central body of the heart and the extended cardiac skeleton of the heart are histologically bound to the muscular myocardium. Collagen contribution to heart performance summarily represents an essential, unique and moving solid anchor opposed to the fluid mechanics of blood movement within the heart. The collagenous structure is an impermeable firewall that excludes both blood and electrical influence (through customary anatomical channels) from the upper {atrial} to the lower [ventricular] chambers of the heart. As proof, one could posit thatatrial fibrillation almost never deteriorates to ventricular fibrillation. Individual valvular leaflets are held in sail shape by collagen under variable pressure. Calcium deposition within collagen occurs as a natural consequence of aging. Calcium rich fixed points in an otherwise moving display of blood and muscle enable current cardiac imaging technology to arrive at ratios essentially stating blood in cardiac input and blood out cardiac output. Specified imaging such as calcium scoringillustrates the utility of this methodology, especially in an aging patient subject to pathology of the collagen underpinning.
Type II collagen and rheumatoid arthritis
According to a study[52] published in the journal Science, oral administration of type II collagen improves symptoms ofrheumatoid arthritis. The authors conducted a randomized, double-blind trial involving 60 patients with severe, active rheumatoid arthritis. A decrease in the number of swollen joints and tender joints occurred in subjects fed with chicken type II collagen for 3 months, but not in those that received a placebo. Four patients in the collagen group had complete remission of the disease. No side effects were evident.
Hydrolyzed type II collagen and osteoarthritis
A published study[53] reports that ingestion of a novel low molecular weight hydrolyzed chicken sternal cartilage extract, containing a matrix of hydrolyzed type II collagen, chondroitin sulfate, and hyaluronic acid, marketed under the brand nameBioCell Collagen, relieves joint discomfort associated with osteoarthritis. A randomized controlled trial (RCT) enrolling 80 subjects demonstrated that BioCell Collagen was well tolerated with no serious adverse event and led to a significant improvement in joint mobility compared to the placebo group on days 35 (p = 0.007) and 70 (p < 0.001).
Cosmetic surgery
Collagen has been widely used in cosmetic surgery, as a healing aid for burn patients for reconstruction of bone and a wide variety of dental, orthopedic and surgical purposes. Both human and bovine collagen is widely used as dermal fillers for treatment of wrinkles and skin aging.[48] Some points of interest are:
1. when used cosmetically, there is a chance of allergic reactions causing prolonged redness; however, this can be virtually eliminated by simple and inconspicuous patch testing prior to cosmetic use, and
2. most medical collagen is derived from young beef cattle (bovine) from certified BSE-free animals. Most manufacturers use donor animals from either "closed herds", or from countries which have never had a reported case of BSE such as Australia, Brazil and New Zealand.
3. porcine (pig) tissue is also widely used for producing collagen sheet for a variety of surgical purposes.
4. alternatives using the patient's own fat, hyaluronic acid or polyacrylamide gels which are readily available.
Bone grafts
As the skeleton forms the structure of the body, it is vital that it maintains its strength, even after breaks and injuries. Collagen is used in bone grafting as it has a triple helical structure, making it a very strong molecule. It is ideal for use in bones, as it does not compromise the structural integrity of the skeleton. The triple helical structure of collagen prevents it from being broken down by enzymes, it enables adhesiveness of cells and it is important for the proper assembly of the extracellular matrix.[54]
Tissue regeneration
Collagen scaffolds are used in tissue regeneration, either in sponges, thin sheets or gels. Collagen has the correct properties for tissue regeneration such as pore structure, permeability, hydrophilicity and it is stable in vivo. Collagen scaffolds are also ideal for the deposition of cells, such as osteoblasts and fibroblasts and once inserted, growth is able to continue as normal in the tissue.[55]
Reconstructive surgical uses
Collagens are widely employed in the construction of artificial skin substitutes used in the management of severe burns. These collagens may be derived from bovine, equine or porcine, and even human sources and are sometimes used in combination with silicones, glycosaminoglycans, fibroblasts, growth factors and other substances.
Collagen is also sold as a pill commercially as a joint mobility supplement with poor references. Because proteins are broken down into amino acids before absorption, there is no reason for orally ingested collagen to affect connective tissue in the body, except through the effect of individual amino acid supplementation.
Collagen is also frequently used in scientific research applications for cell culture, studying cell behavior and cellular interactions with the extracellular environment.[56]
Wound care management uses
Collagen is one of the body’s key natural resources and a component of skin tissue that can benefit all stages of the wound healing process. When collagen is made available to the wound bed, closure can occur. Wound deterioration, followed sometimes by procedures such as amputation, can thus be avoided.
Collagen is a natural product, therefore it is used as a natural wound dressing and has properties that artificial wound dressings do not have. It is resistant against bacteria, which is of vital importance in a wound dressing. It helps to keep the wound sterile, because of its natural ability to fight infection. When collagen is used as a burn dressing, healthygranulation tissue is able to form very quickly over the burn, helping it to heal rapidly.[57]
Throughout the 4 phases of wound healing, collagen performs the following functions in wound healing:
· Guiding function: Collagen fibers serve to guide fibroblasts. Fibroblasts migrate along a connective tissue matrix.
· Chemotactic properties: The large surface area available on collagen fibers can attract fibrogenic cells which help in healing.
· Nucleation: Collagen, in the presence of certain neutral salt molecules can act as a nucleating agent causing formation of fibrillar structures. A collagen wound dressing might serve as a guide for orienting new collagen deposition and capillary growth.
· Hemostatic properties: Blood platelets interact with the collagen to make a hemostatic plug.
References [edit]
1. ^ Müller, Werner E. G. (2003). "The Origin of Metazoan Complexity: Porifera as Integrated Animals". Integrated Computational Biology 43 (1): 3–10. doi:10.1093/icb/43.1.3.
2. ^ Di Lullo, Gloria A.; Sweeney, Shawn M.; Körkkö, Jarmo; Ala-Kokko, Leena & San Antonio, James D. (2002). "Mapping the Ligand-binding Sites and Disease-associated Mutations on the Most Abundant Protein in the Human, Type I Collagen". J. Biol. Chem. 277 (6): 4223–4231. doi:10.1074/jbc.M110709200. PMID 11704682.
3. ^ Sikorski, Zdzisław E. (2001). Chemical and Functional Properties of Food Proteins. Boca Raton: CRC Press. p. 242.ISBN 1-56676-960-4.
4. ^ Wyckoff, R.; Corey, R. & Biscoe, J. (1935). "X-ray reflections of long spacing from tendon". Science 82 (2121): 175–176.Bibcode:1935Sci....82..175W. doi:10.1126/science.82.2121.175. PMID 17810172.
5. ^ Clark, G.; Parker, E.; Schaad, J. & Warren, W. J. (1935). "New measurements of previously unknown large interplanar spacings in natural materials". J. Amer. Chem. Soc 57 (8): 1509. doi:10.1021/ja01311a504.
6. ^ Balasubramanian, D . (October 2001). "GNR — A Tribute". Indian Academy of Sciences.
7. ^ Leonidas, Demetres D.; et al., GB; Jardine, AM; Li, S; Shapiro, R; Acharya, KR (2001). "Binding of Phosphate and pyrophosphate ions at the active site of human angiogenin as revealed by X-ray crystallography". Protein Science 10 (8): 1669–1676. doi:10.1110/ps.13601. PMC 2374093. PMID 11468363.
8. ^ Subramanian, Easwara (2001). "Obituary: G.N. Ramachandran". Nature Structural & Molecular Biology 8 (6): 489–491.doi:10.1038/88544. PMID 11373614.
9. ^ Fraser, R. D.; MacRae, T. P. & Suzuki, E. (1979). "Chain conformation in the collagen molecule". J Mol Biol 129 (3): 463–481. doi:10.1016/0022-2836(79)90507-2. PMID 458854.
10. ^ Okuyama, K.; et al., K; Arnott, S; Takayanagi, M; Kakudo, M (1981). "Crystal and molecular structure of a collagen-like polypeptide (Pro-Pro-Gly)10". J Mol Biol 152 (2): 427–443. doi:10.1016/0022-2836(81)90252-7. PMID 7328660.
11. ^ Traub, W.; Yonath, A. & Segal, D. M. (1969). "On the molecular structure of collagen". Nature 221 (5184): 914–917.Bibcode:1969Natur.221..914T. doi:10.1038/221914a0.
12. ^ Bella, J.; Eaton, M.; Brodsky, B.; Berman, H. M. (1994). "Crystal and molecular structure of a collagen-like peptide at 1.9 A resolution". Science 266 (5182): 75–81. Bibcode:1994Sci...266...75B. doi:10.1126/science.7695699. PMID 7695699.
13. ^ a b Hulmes, D. J. & Miller, A. (1979). "Quasi-hexagonal molecular packing in collagen fibrils". Nature 282 (5741): 878–880.Bibcode:1979Natur.282..878H. doi:10.1038/282878a0. PMID 514368.
14. ^ Jesior, J. C.; Miller, A. & Berthet-Colominas, C. (1980). "Crystalline three-dimensional packing is general characteristic of type I collagen fibrils". FEBS Lett 113 (2): 238–240. doi:10.1016/0014-5793(80)80600-4. PMID 7389896.
15. ^ Fraser, R. D. B. & MacRae, T. P. (1981). "Unit cell and molecular connectivity in tendon collagen". Int. J. Biol. Macromol. 3(3): 193–200. doi:10.1016/0141-8130(81)90063-5.
16. ^ Fraser, R. D.; MacRae, T. P.; Miller, A. (1987). "Molecular packing in type I collagen fibrils". J Mol Biol 193 (1): 115–125.doi:10.1016/0022-2836(87)90631-0. PMID 3586015.
17. ^ Wess, T. J.; et al., AP; Wess, L; Miller, A (1998). "Molecular packing of type I collagen in tendon". J Mol Biol 275 (2): 255–267. doi:10.1006/jmbi.1997.1449. PMID 9466908.
18. ^ Raspanti, M.; Ottani, V.; Ruggeri, A. (1990). "Subfibrillar architecture and functional properties of collagen: a comparative study in rat tendons". J Anat. 172: 157–164. PMC 1257211. PMID 2272900.
19. ^ Holmes, D. F.; Gilpin, C. J.; Baldock, C.; Ziese, U.; Koster, A. J.; Kadler, K. E. (2001). "Corneal collagen fibril structure in three dimensions: Structural insights into fibril assembly, mechanical properties, and tissue organization". PNAS 98 (13): 7307–7312. Bibcode:2001PNAS...98.7307H. doi:10.1073/pnas.111150598. PMC 34664. PMID 11390960.
20. ^ Holmes, D. F.; Kadler, KE (2006). "The 10+4 microfibril structure of thin cartilage fibrils". PNAS 103 (46): 17249–17254.Bibcode:2006PNAS..10317249H. doi:10.1073/pnas.0608417103. PMC 1859918. PMID 17088555.
21. ^ a b c Orgel, J. P.; et al., TC; Miller, A; Wess, TJ (2006). "Microfibrillar structure of type I collagen in situ". PNAS 103 (24): 9001–9005. Bibcode:2006PNAS..103.9001O. doi:10.1073/pnas.0502718103. PMC 1473175. PMID 16751282.
22. ^ Okuyama, K; Bächinger, HP; Mizuno, K; Boudko, SP; Engel, J; Berisio, R; Vitagliano, L (2009). "Comment on Microfibrillar structure of type I collagen in situ by Orgel et al. (2006), Proc. Natl Acad. Sci. USA, 103, 9001–9005". Acta Crystallogr D Biol Crystallogr 65 (Pt9): 1009–10. doi:10.1107/S0907444909023051. PMID 19690380.
23. ^ Narayanaswamy, Radhakrishnan; Shanmugasamy, Sangeetha; Shanmugasamy, Sangeetha; Gopal, Ramesh; Mandal, Asit (2011). "Bioinformatics in crosslinking chemistry of collagen with selective crosslinkers". BMC 4: 399. doi:10.1186/1756-0500-4-399.
24. ^ a b c d e f Szpak, Paul (2011). "Fish bone chemistry and ultrastructure: implications for taphonomy and stable isotope analysis". Journal of Archaeological Science 38 (12): 3358–3372. doi:10.1016/j.jas.2011.07.022.
25. ^ Shoulders, M. D.; Raines, R. T. (2009). "Collagen structure and stability". Annu. Rev. Biochem. 78: 929–958.doi:10.1146/annurev.biochem.77.032207.120833. PMC 2846778. PMID 19344236.
26. ^ Gorres, K. L.; Raines, R. T. (2010). "Prolyl 4-hydroxylase". Crit. Rev. Biochem. Mol. Biol. 45 (2): 106–24.doi:10.3109/10409231003627991. PMC 2841224. PMID 20199358.
27. ^ Myllylä, R.; Majamaa, K.; Günzler, V.; Hanauske-Abel, H. M.; Kivirikko, K. I. (1984). "Ascorbate is consumed stoichiometrically in the uncoupled reactions catalyzed by propyl 4-hydroxylase and lysyl hydroxylase". J. Biol. Chem. 259 (9): 5403–5.PMID 6325436.
28. ^ Houck, J. C.; Sharma, V. K.; Patel, Y. M.; Gladner, J. A. (1968). "Induction of Collagenolytic and Proteolytic Activities by AntiInflammatory Drugs in the Skin and Fibroblasts". Biochemical Pharmacology 17 (10): 2081–2090. doi:10.1016/0006-2952(68)90182-2. PMID 4301453.
29. ^ Al-Hadithy, H.; et al., DA; Addison, IE; Goldstone, AH; Snaith, ML (1982). "Neutrophil function in systemic lupus erythematosus and other collagen diseases". Ann Rheum Dis 41 (1): 33–38. doi:10.1136/ard.41.1.33. PMC 1000860.PMID 7065727.
30. ^ Hulmes, D. J. (2002). "Building collagen molecules, fibrils, and suprafibrillar structures". J Struct Biol 137 (1–2): 2–10.doi:10.1006/jsbi.2002.4450. PMID 12064927.
31. ^ a b Hulmes, D. J. (1992). "The collagen superfamily—diverse structures and assemblies". Essays Biochem 27: 49–67.PMID 1425603.
32. ^ Perumal, S.; Antipova, O. & Orgel, J. P. (2008). "Collagen fibril architecture, domain organization, and triple-helical conformation govern its proteolysis". PNAS 105 (8): 2824–2829. Bibcode:2008PNAS..105.2824P.doi:10.1073/pnas.0710588105. PMC 2268544. PMID 18287018.
33. ^ Sweeney, S. M.; et al., JP; Fertala, A; McAuliffe, JD; Turner, KR; Di Lullo, GA; Chen, S; Antipova, O et al. (2008). "Candidate Cell and Matrix Interaction Domains on the Collagen Fibril, the Predominant Protein of Vertebrates". J Biol Chem 283 (30): 21187–21197. doi:10.1074/jbc.M709319200. PMC 2475701. PMID 18487200.
34. ^ Twardowski, T.; et al., A.; Orgel, J. P.R.O.; San Antonio, J. D. (2007). "Type I collagen and collagen mimetics as angiogenesis promoting superpolymers". Curr Pharm Des 13 (35): 3608–3621. doi:10.2174/138161207782794176.
35. ^ Minary-Jolandan, M; Yu, MF (2009). "Nanomechanical heterogeneity in the gap and overlap regions of type I collagen fibrils with implications for bone heterogeneity". Biomacromolecules 10 (9): 2565–70. doi:10.1021/bm900519v. PMID 19694448.
36. ^ Ross, M. H. and Pawlina, W. (2011) Histology, 6th ed., Lippincott Williams & Wilkins, p. 218.
37. ^ Sabiston textbook of surgery board review, 7th edition. Chapter 5 wound healing, question 14
38. ^ Söderhäll, C.; Marenholz, I.; Kerscher, T.; Rüschendorf, F; Rüschendorf, F.; Esparza-Gordillo, J.; et al., C; Mayr, G et al. (2007). "Variants in a Novel Epidermal Collagen Gene (COL29A1) Are Associated with Atopic Dermatitis". PLoS Biology 5(9): e242. doi:10.1371/journal.pbio.0050242. PMC 1971127. PMID 17850181.
39. ^ a b Mahajan, VB, Olney, AH, Garrett, P, Chary, A, Dragan, E, Lerner, G, Murray, J & Bassuk, AG (2010). "Collagen XVIII mutation in Knobloch syndrome with acute lymphoblastic leukemia". American journal of medical genetics. Part A 152A (11): 2875–9. doi:10.1002/ajmg.a.33621. PMC 2965270. PMID 20799329.
40. ^ Gajko-Galicka, A (2002). "Mutations in type I collagen genes resulting in osteogenesis imperfecta in humans". Acta biochimica Polonica 49 (2): 433–41. PMID 12362985.
41. ^ Horton, WA, Campbell, D, Machado, MA & Chou, J (1989). "Type II collagen screening in the human chondrodysplasias".American journal of medical genetics 34 (4): 579–83. doi:10.1002/ajmg.1320340425. PMID 2624272.
42. ^ Hamel, BC, Pals, G, Engels, CH, van den Akker, E, Boers, GH, van Dongen, PW & Steijlen, PM (1998). "Ehlers-Danlos syndrome and type III collagen abnormalities: A variable clinical spectrum". Clinical genetics 53 (6): 440–6. PMID 9712532.
43. ^ Kashtan, CE (1993) "Collagen IV-Related Nephropathies (Alport Syndrome and Thin Basement Membrane Nephropathy)", in RA Pagon, TD Bird, CR Dolan, K Stephens & MP Adam (eds), GeneReviews, University of Washington, Seattle, Seattle WAPMID 20301386.
44. ^ Shuster, S (2005). "Osteoporosis, a unitary hypothesis of collagen loss in skin and bone". Medical hypotheses 65 (3): 426–32. doi:10.1016/j.mehy.2005.04.027. PMID 15951132.
45. ^ Fratzl, P. (2008). Collagen: Structure and Mechanics. New York: Springer. ISBN 0-387-73905-X.
46. ^ Buehler, M. J. (2006). "Nature designs tough collagen: Explaining the nanostructure of collagen fibrils". PNAS 103 (33): 12285–12290. Bibcode:2006PNAS..10312285B. doi:10.1073/pnas.0603216103. PMC 1567872. PMID 16895989.
48. ^ a b Dermal Fillers | The Ageing Skin. Pharmaxchange.info. Retrieved on 2013-04-21.
49. ^ "Gelatin's Advantages: Health, Nutrition and Safety". gmap-gelatin.com.
50. ^ Walker, Amélie A. (May 21, 1998). "Oldest Glue Discovered". Archaeology.
51. ^ Ennker, I. C.; et al., JüRgen; Schoon, Doris; Schoon, Heinz Adolf; Rimpler, Manfred; Hetzer, Roland (1994). "Formaldehyde-free collagen glue in experimental lung gluing". Ann Thorac Surg. 57 (6): 1622–1627. doi:10.1016/0003-4975(94)90136-8.PMID 8010812.
52. ^ Trentham, D.; Dynesius-Trentham, R.; Orav, J.; Combitchi, D.; Lorenzo, C.; Sewell, K.; Hafler, D. & Weiner, H. (1993). "Effects of Oral Administration of Type II Collagen on Rheumatoid Arthritis". Science 261 (5119): 1727–1730.Bibcode:1993Sci...261.1727T. doi:10.1126/science.8378772.
53. ^ Schauss, A., Stenehjem, J., Park, J., Endres, J., and Clewell, A. (2012). "Effect of the novel low molecular weight hydrolyzed chicken sternal cartilage extract, BioCell Collagen, on improving osteoarthritis-related symptoms: A randomized, double-blind, placebo-controlled trial". Journal of agricultural and food chemistry 60 (16): 4096–101. doi:10.1021/jf205295u.PMID 22486722.
54. ^ Cunniffe, G; F O'Brien (2011). "Collagen scaffolds for orthopedic regenerative medicine". The Journal of the Minerals, Metals and Materials Society 63 (4): 66–73. doi:10.1007/s11837-011-0061-y.
55. ^ Oliveira, S; R Ringshia, R Legeros, E Clark, L Terracio, C Teixeira M Yost (2009). "An improved collagen scaffold for skeletal regeneration". Journal of Biomedical Materials: 371–379. PMID 20186736.
56. ^ Blow, Nathan (2009). "Cell culture: building a better matrix". Nature Methods 6 (8): 619–622. doi:10.1038/nmeth0809-619.
57. ^ Singh, O; SS Gupta, M Soni, S Moses, S Shukla, RK Mathur (2011). "Collagen dressing versus conventional dressings in burn and chronic wounds: a retrospective study". Journal of Cutaneous and Aesthetic Surgery 4 (1): 12–16.doi:10.4103/0974-2077.79180. PMC 3081477. PMID 21572675.
This article is fabulous.. Your way presenting the article is completely differ from others, Information about the types collagen and the use of that collagen products is nice.
ReplyDeleteThanks so much. You have encouraged me to get busy and post more things!
ReplyDelete