Cellulose networks

The processing flexibility of plastic-cellulose networks gives rise to products in various thickness, from a material only a few millimeters thick to structural panels up to several centimeters thick, that include [14] ... 

If cellulose exists in the cell wall as a network within a pectic matrix, the pectin that is within about 2nm of the cellulose network maybe on or near exposed surfaces of cellulose microfibrils. Both the gel and the eggbox pectins are represented in this low mobility spectrum. 

The wall of the BASYC tubes consists of BC loaded with water in the nanofiber network up to 99%. The hollow space of the material transports water, monovalent ions and small molecules, but not biopolymers or corpuscular blood constituents. The stored water not only stabilizes the cellulose network, but also contributes to the tissue- and hemocompatibility of the nanocellulose device. 

The TEMs revealed a change of material structure in the contact region with the newly built blood vessel. Beside cellulose we discovered still different structures in region 1 (Fig. 24a). Branches of fibroblasts, cellular compounds of the newly built vessel, have penetrated the cellulosic network and in this way anchored themselves in the artificial vessel prosthesis. Sections of the fibroblast branches and the contact region are clearly visible (Fig. 24b). 

The immobilization of biologically active substances within the cellulosic network structure to optimize healing and regeneration processes as well as to test the potential pharmaceutical suitability of natural or synthetic substances are also study points for the future. 

Calcified scales formed inside the Golgi and then extruded have so far only been found in coccolithophorids. In other forms, the matrix is formed in the Golgi but calcification takes place in the cytoplasm. In some cases, the plates of coccolithophorids calcify inside the T-shaped cisternae where the stem is associated with the Golgi stack while the scale is already forming with its future distal surface facing the stack. The scales of coccolithophorids always consist of two layers of a cellulose network of microfibrils radially and concentrically arranged. The outer layer of the scale is made up of acidic polysaccharides and small amounts of protein, probably containing hydroxy-... 

The primary cell wall of dicotyledonous plants consists of cellulose microfibrils dispersed within a matrix of predominantly non-cellulosic polysaccharides, including xyloglucans and pectic polysaccharides. The xyloglucans are neutral polysaccharides which bind to the cellulose microfibrils through secondary interactions, and have the ability to crosslink the fibrillar cellulose network. This fibrillar network is then dispersed in a network of the pectic polysaccharides.1 The pectic polysaccharide network also forms the middle lamella in dicotyledons and is responsible for cell-cell adhesion. 

Ttmes, F.G., Troncoso, O.P., Lopez, D., Grande, C., Gomez, C.M. Reversible stress softerring and stress recovery of cellulose networks. Soft Matter 5, 4185-4190 (2009)... 

Fig. 2.8 SEM niiciogn hs of a hap-bacteiial cellulose composite showing the hap particles inside the cellulose network [154]...

ECM-based hemostatic aids function in both active and passive ways. Collagen or cellulose networks aid in platelet adhesion and organized clot formation. For instance, collagen-based products have gained popularity due to their postulated superior... 

Cellulose-based ion exchangers. Their chemical structure is a hydrophilic cellulose network having acidic (carboxylmethyl, sulfoethyl, etc.) or basic (amino-ethyl, diethylaminoethyl, etc.) groups. 

Using a patented matrix technique, A. xylinum is able to build up cellulose network as very regularly formed tubes of different length, wall thickness, and inner diameter (Fig. 21.14). The marked BASYC tube has an inner diameter of 1 mm, length of about 5 mm, and wall thickness of 0.7 mm. These parameters are sufficient for experimental microsurgical requirements. 

Freeze etching of stelar tissue in Zea mays roots has demonstrated the association of globular complexes with the ends of nascent microfibrils. The results support a model for the synthesis of cellulose in which an enzyme complex in the granule adds D-glucopyranosyl residues to the developing end of a microfibril. The ultrastructure of the cellulosic network of the primary cell wall of pine wood and its development during the formation of tracheids have been studied by electron microscopy. ... 

Some ascidians possess two more cellulosic structures other than the tunic. These cellulosic structures have been observed by scanning electron microscopy after treatment with the Updegraff reagent (Updegraff 1969) that removes non-cellulosic substances. One of these cellulosic structures is a cellulose network that is distributed in the hemocoel (the tissue equivalent to a blood vessel of vertebrates) (Kimura and Itoh 1997), and the other is a coiled cord-like structure called the tunic cord (Kimura and Itoh 1998). 

Figure 13-7. A schematic illustration showing the step-wise involvement of glomerulocytes in the formation of a cellulose network in the hemocoel (1) glomerulocytes are transferred into hemocoel (2) bundles of cellulose skeleton are released in the hemocoel (3) cellulose microfibrils of the skeleton are untied to make cellulose network. Tu = tunic, ep = epidermis, gl = glomerulocyte, ae =atrial epitherium, b = blood cell (See Color Plate of this figure beginning on page 355)...

ICimura S. and Itoh T. 1997. Cellulose network of hemocoel in selected compound styehd ascidians. J Electron Microsc 46 327-335. 

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