Studies on Biopsy Samples and Tissues

In future, in vivo MRS might provide data on tumor metabolism and the response to therapy [31]. First such studies are reported below. 

The myometrial, decidual, placental and fetal membrane phospholipids were studied by P NMR [38]. The tissue samples were pulverized and extracted. The signals of phosphatidylcholine PCho, phosphatidylethanolamine, sphingomyelin SM and phosphatidyli-nositol were found. The ratio PCho/SM decreased during pregnancy in the decidua, placenta and fetal membranes but not in the myometrium. The fetal tissues, fetal membranes and placenta contained about twice as much phospholipid as the maternal tissues. 

Perfusion of skin with transdermal-penetration-enhancing agents such as ethanol, DMSO-ds and propylene glycol was studied by in vitro P NMR [39]. Epidermal strips from abdominal pig skin were placed in a 10 mm O.D. NMR tube modified for continuous perfusion with buffered salt solution and a serial spectra were recorded on a Broker AMX500 spectrometer. Signal intensities for phosphomono- and di-esters PME and PDE, phosphocreatine PCr, inorganic phosphate Pi and nucleotide triphosphorate, 3-NTP were followed in time. Additional spectra were recorded when the perfusion medium contained dexamethasone. The dexamethasone perfusion resulted in a dose-dependent decrease in PCr and NTP levels and had an effect on PME metabolism. 

The quality of the P spectrum of epidermis encourages further studies. Investigations of drugs applied on skin as well as skin care cosmetics, which are of importance for the pharmaceutical industry, may be carried out. 

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