Organ tissue analysis

TXRF is most applicable to liquid samples, but success has also been achieved with direct analysis of some solids, e.g. very thin sections of organic tissue and polymer film. Alternatively, small amounts of solid material can be analysed by TXRF after acid digestion. 

Friction wear and dissolution of orthopaedic implant systems were examined by PIXE, SR-XRF and XAS [300]. From XAFS analysis, it appeared that the chemical state of Fe had changed as a consequence of dissolution in the organic tissue. 

A matrix of light elements (e.g. plastic, or organic tissue) containing a large number of trace elements constitutes an ideal sample for PIXE analysis, and air pollution samples provide a good example of the technique. 

Lemaire R, Wisztorski M, Desmons A, et al. MALDI-MS direct tissue analysis of proteins improving signal sensitivity using organic treatments. Anal. Chem. 2006 78 7145-7153. 

In most instances the specimens will be self-evident (e.g., samples of blood, plasma, serum, urine, spinal fluid, aqueous humor, organs, tissues, and tissue fractions that are taken from a test system with the intention of performing an examination or analysis). In other instances the definition may not be as clear. For example, the assay plates used in the mammalian cell transformation assay and the mammalian point mutation assay are considered specimens even though they bear many of the attributes of a test system. For these assays, the originally plated cells plus media and excipients are the test system. After treatment with the test or... 

In the past decade, eight inherited disorders have been linked to specific enzyme defects in the isoprenoid/cholesterol biosynthetic pathway after the finding of abnormally increased levels of intermediate metabolites in tissues and/or body fluids of patients (Table 5.1.1) [7, 9, 10]. Two of these disorders are due to a defect of the enzyme mevalonate kinase, and in principle affect the synthesis of all isoprenoids (Fig. 5.1.1) [5]. The hallmark of these two disorders is the accumulation of mevalonic acid in body fluids and tissues, which can be detected by organic acid analysis, or preferably, by stable-isotope dilution gas chromatography (GC)-mass spectrometry (GC-MS) [2]. Confirmative diagnostic possibilities include direct measurement of mevalonate kinase activities in white blood cells or primary skin fibroblasts [3] from patients, and/or molecular analysis of the MVK gene [8]. 

Differential tissue analysis is not frequent in studies involving small invertebrates, such as bivalves, polychaetes, and gastropods, since, as discussed earlier, their diminutive size poses challenging methodological problems. Nonetheless, examples of the usefulness of this approach can be found in the literature. One study compared the specific tissue distribution of cadmium and two forms of mercury in the clam Corbicula fluminea when exposed to contaminated water or sediments 85 the metal distributions in five selected organs were reported to display strong specificities, in accordance... 

The IMS assay has been applied to the analysis of animal organ tissue, skin, whole body, human and animal cancer tissue, and drug formulation. It was also used for MS imaging study on mammalian cell [147], single neurons [148,149], bacteria [150], and MS imaging of features smaller than the size of laser beam [151],... 

To appraise the extent of environmental contamination is a problem in organic pesticide analysis. Analytical methods for such diverse samples as air and human tissue have been developed and are yielding important information. The fate and persistence of pesticides constitutes another complex problem. It includes consideration of environmental and biological effects upon pesticides, how they move in rivers, and how they are translocated from one environmental medium to another. Finally, there is the question of damage control. Can we reduce the introduction of pesticides into air and water If not, can we effectively remove these poisons from the parts we consume ... 

Sun L, Sung KB, Dentinger C, Lutz B, Nguyen L, Zhang JW, Qin HY, Yamakawa M, Cao MQ, Lu Y, Chmura AJ, Zhu J, Sn X, Berlin A A, Chan S, Knudsen B (2007) Composite organic-inorganic nanoparticles as Raman labels for tissue analysis. Nano Lett 7 351-356... 

The same data for this hypothetical chemical mixture were subjected to a TTD analysis (Table 21.4). Here a HI value for each affected organ, tissue, or system is determined and combined with the exposure value to determine a HI for each effect of each chemical. By this more robust approach, concern is raised if the HI is a value above 1.0. Under the IT D approach, kidney, heart, and spleen would each have HI values unlikely to lead to a level of concern. 

Whole body selenium is about 15 mg, as estimated by direct tissue analysis and radioisotope techniques, with the tissue concentration of selenium being highest in the kidney and the liver followed by the other organs. Radioisotope-labeled selenium accumulates initially in the liver, kidneys, and lungs. Selenium present in some selenocysteine proteins appears to be a functional reserve. When dietary selenium is limited, synthesis of glutathione peroxidase (GSHP)x-l is... 

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