Collagen , comparative studies

Yamaguchi, K., Lav6ty, J. and Love, R.M. (1976). The connective tissues of fish. vm. Comparative studies of hake, cod and catfish collagens. Journal of Food Technology 11,389-399. 

Recent comparative studies on the rate of formation of the collagen-fold in HjO and DsO seem to support the possibility of intrachain water bridges linking adjacent carbonyl oxygens. These studies are discussed in Section V. 

These comparative studies show that only the hydration of acid-soluble collagen fibers exhibits well defined energetic steps which can be attributed respectively to intramolecular water, water in microfibrils and "free" water giving rise to an overall swelling of the fiber. 

In platelet perfusion experiments, platelet accumulation on reactive adhesive surfaces such as collagen coated glass shows a steady decrease with distance from the capillary inlet, as previously observed in similar flow systems (20,21). This axial dependence does not, in our system, appear to follow a simple mathematical law as a function of distance from the capillary entrance (22). Platelet deposition is thus calculated as the mean deposition over the entire length ( < 10 cm) of a single capillary and in comparative studies capillaries cf equal length and internal diameter are considered. 

DeLustro E, CondaU RA, Nguyen MA, McPherson JM. A comparative study of the biologic and immunologic response to medical devices derived from dermal collagen. J Biomed Mater Res 1986 20 109 20. 

Piez, K.A. and co-workers (1968) Comparative studies on the chemistry of collagen utilizing cyanogen bromide cleavage. Broohhaven Symp. Biol, 21, 345-357. 

Black, B.S., Ghcr, M.E.. Sandifer, J.B., Fucini, S.E. and Richardson, AC. (1994) Comparative study of collagen and expanded polvtetrafluoroethvlene membranes in die treamient of hmnan class III furcation defects. /. PeriodontoL, 65, 598-604. 

Biomimetic configurational arrays of HAp nanocrystals on collagen (Col) and chondroifin sulphate (ChS) were comparatively studied by Rhee et al. [225]. The nanocomposites of Col/HAp, ChS/HAp, and Col/ChS/HAp were synthesized through a precipitation method with calcium hydroxide suspension and phosphoric acid solution containing Col, ChS, and their mixture, respectively. The (002) diffraction of the synthesized HAp crystals on a Col fibre showed around 60° arching angle, whereas that on a ChS fibre showed just around 10° (Fig. 19). 

Leach CM, Thorbum GD (1982) A comparative study of collagen induced thromboxane release from platelets of different species implications for human atherosclerosis models. Prostaglandins 24 47 - 59... 

Ambrose (1990, 1993) found that for most samples well-preserved collagen had at least 3% carbon and 1% nitrogen. If this criterion is applied in this study, two of our 22 samples show aberrant values for carbon and one of 22 is aberrant for nitrogen, with three of the samples containing 1% nitrogen (Table 7.1). Of the three samples where we can compare bone with hpid-removed and lipids intact, both C and N concentrations are within acceptable limits in the lipid-removed sample, but substantially lower in most layers with lipid intact. The concentrations of both C and N are low, but within acceptable criteria, in the sample with well preserved histology (C = 5.11%, N= 1.77%). 

Several authors, beginning with Kmeger and Sullivan (1984), have noted a smaller 8 C fractionation between collagen and apatite (A,p.co) in carnivores as compared to herbivores. These authors presented a model to accoimt for this, and the observation was confirmed in studies by Lee-Thorp and van der Merwe (1991) of populations of carnivores and herbivores that differed widely in their intake of C3- and C4-based foods. Here 1 shall show how this effect might be accounted for as a consequence of partial blocking of AA synthesis from lipids. 

In a histometric, immunohistochemical and ultrastructural study, TCA peeling in concentrations of 10,20 and 30% were compared with dermabrasion in nine dark-skinned patients (Fitzpatrick s IV and V) with photodamage [24]. Both procedures induced increasing amounts of types I and III collagen. However,... 

Silk fibers or monolayers of silk proteins have a number of potential biomedical applications. Biocompatibility tests have been carried out with scaffolds of fibers or solubilized silk proteins from the silkworm Bombyx mori (for review see Ref. [38]). Some biocompatibility problems have been reported, but this was probably due to contamination with residual sericin. More recent studies with well-defined silkworm silk fibers and films suggest that the core fibroin fibers show in vivo and in vivo biocompatibility that is comparable to other biomaterials, such as polyactic acid and collagen. Altmann et al. [39] showed that a silk-fiber matrix obtained from properly processed natural silkworm fibers is a suitable material for the attachment, expansion and differentiation of adult human progenitor bone marrow stromal cells. Also, the direct inflammatory potential of silkworm silk was studied using an in vitro system [40]. The authors claimed that their silk fibers were mostly immunologically inert in short and long term culture with murine macrophage cells. 

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