Tissue Markers

For tissue markers, biodegradable polymers and copol mers can be combined with or without ionic and non-ionic contrast agents, depending upon the application. For example, no contrast agent is 

Formulations that include contrast agents are designed to allow the radiopacity of the markers to last for an extended period of time so that they can be seen under X-ray or other imaging means for further diagnostic or intervention procedures at a date that may be weeks or months after implanting of the marker. 

Some of these pol miers and copolymers do not possess the mechanical properties that are required for certain applications. For example, as implants for soft tissue poly(lactide)s, poly(glycolide)s, PCL, poly(dioxanone) and their copolymers may require increased flexibiUty and a modulus of elasticity that is closer to soft tissue. 

Some hydrogels, due to their water content, provide a more flexible structure that is similar to soft tissue. Therefore, by combining the pol5uners that lack certain required mechanical properties such as a suitable modulus of rigidity or modulus of elasticity with hydrogels, suitable degradation and drug delivery properties are obtainable and an exterior is achieved that has mechanical properties similar to the mechanical properties of soft tissue. 

The above-mentioned pol5miers are designed to provide a sustainable and gradual degradation and therefore a slow release of drugs in the course of the degradation of the pol5uneric substrate. 

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R3. Rochefort, H., Cathepsin D in breast cancer A tissue marker associated with metastasis. Eur. 

Peripheral tissue markers include high-molecular-weight complex biomolecules (receptors) and enzyme systems that can be obtained from outside the CNS (e.g., in platelets, lymphocytes, skin fibroblasts, and erythrocytes) and are thought to reflect or parallel central neuronal activity. 

For residue monitoring purposes, it is frequently useful to define MRLs for a particular marker residue. A specific quantitative analytical method for measuring the concentration of the residue with the required sensitivity must be available. The MRL establishes the concentration of the marker residue permitted in the target tissue. Marker residue and target tissue are selected in such a way that total residues in each edible tissue are at or below its safe concentration if the marker residue is at or below the MRLs. For milk or eggs, it may be necessary to select a marker residue different from the marker residue selected for the target tissue representing the edible carcass. 

Goodwin R, Dungworth J, Cobb S, Pitt A (2008) Time-dependent evolution of tissue markers by MALDI-MS imaging. Proteomics 8 3801-3808. doi 10. 1002/pmic.2008002001... 

The major disadvantages of these cultures are the accentuated chromosomal instability, the larger phenotype variation in relation to the donor tissue, and the disappearance of specific and characteristic tissue markers (Freshney, 1994). 

Lloyd RV, Wilson BS. Specific endocrine tissue marker defined by a monoclonal antibody. Science. 1983 222 628-630. 

Vis AN, van Rhijn BW, Noordzij MA, et al. Value of tissue markers p27(kipl), MIB-1, and CD44s for the pre-operative prediction of tumour features in screen-detected prostate cancer. J Pathol. 2002 197 148. 

Many studies show that the use of PCR-based molecular methods to amplify PSA-mRNA as molecular marker offer a sensitive assay for the detection of extraprostatic PSA synthesizing cells suitable for monitoring and detection of micrometastases and circulating tumor cells originated from prostatic carcinoma. The use of PSA as a molecular target proved to be more sensitive than the amplification of other prostate-specific tissue markers like prostate-specific membrane antigen (PSMA) or human glandular kallikrien (a member of the kallikrien family of serine proteases with trypsin like activity). 

Ibrahim T, Sacanna E, Gaudion M, Mereatali KL, Scarpi E, Zoli W, Serra P, Kang Y, Amadoii D. Role of RANK, RANKL, OPG, and CXCR4 tissue markers in predicting bone metastases in breast cancer patients. Clin Breast Cancer. 2011 11 369-75. 

Sugitachi, A. Wakabayashi, X. Viscous tissue markers containing chitosan for endoscopic surgery, surgery, or animal experiments. Jpn. Kokai Tokkyo Koho JP 2(X)7262062, 2(X)7 Chem. Abstr. 2007,147, 422441. 

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