Determination of coenzyme Q10 in functional and neoplastic human renal tissues.
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Chromatography, High Pressure Liquid↗
Biomedical subjects
Vitaliano Tugnoli
Publications and source records attributed to Vitaliano Tugnoli.
Ex vivo HR-MAS MRS of human meningiomas: a comparison with in vivo 1H MR spectra.
We report on the magnetic resonance spectroscopy (MRS) characterisation of different human meningiomas. Three histological subtypes of meningiomas (meningothelial, fibrous and oncocytic) were analysed both through in vivo and ex vivo MRS experiments. The ex vivo high-resolution magic angle spinning (HR-MAS) investigations, permitting an accurate description of the metabolic profile, are very helpful for the assignment of the resonances in vivo of human meningiomas and for the validation of the quantification procedure of in vivo MR spectra. By using one- and two-dimensional experiments, we were able to identify several metabolites in different histological subtypes of meningiomas. Our spectroscopic data confirmed the presence of the typical metabolites of these benign neoplasms and, at the same time, that meningomas with different morphological characteristics have different metabolic profiles, particularly regarding macromolecules and lipids. The ex vivo spectra allowed a better understanding and interpretation of the in vivo MR spectra, showing that the HR-MAS MRS technique could be a complementary method to strongly support the in vivo MR spectroscopy and increase its clinical potentiality.
Aged↗
Cholesteryl esters in malignancy.
Cholesteryl esters, formed by the esterification of cholesterol with long-chain fatty acids, on one hand, are the means by which cholesterol is transported through the blood by lipoproteins, on the other, the way cholesterol itself can be accumulated in the cells. Therefore, these important molecules play an active part in metabolic pathways that form the basis of cholesterol trafficking and homeostasis. The role of different regulatory mechanisms in cholesterol homeostasis in physiologic and neoplastic conditions with emphasis on intracellular content of cholesteryl esters is here reviewed. Numerous studies carried out on tumor cell lines, experimental tumors, and human tumors have shown an abnormal cholesterol metabolism that is reflected by an increase in intracellular cholesteryl esters due to an alteration in all the mechanisms that form the basis of regulation, in particular: cholesterol de novo biosynthesis; uptake of exogenous cholesterol LDL receptor mediated; cholesterol esterification mediated by the ACAT activity; cholesterol efflux HDL receptor mediated. The most recent analytic-spectroscopic applications that permit cholesteryl ester determination on tumor lipidic extracts and directly in vivo are also reported. This review gives an overview of cholesterol homeostasis in physiological and pathological conditions where cholesteryl esters are over-expressed.
Cell Line, Tumor↗
Cholesteryl ester detection in a human urothelial carcinoma.
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Cholesterol Esters↗
Effect of low molecular size humic substances on nitrate uptake and expression of genes involved in nitrate transport in maize (Zea mays L.).
In this study, a detailed characterization of earthworm low molecular size humic substances (LMS) was performed and these substances were used to study their effect on the nitrate influx in roots, tissue nitrate content, and expression of maize genes putatively involved in nitrate uptake in maize (Zea mays L.). The results show that the humic fraction with low molecular size used in this study is endowed with the characteristic structural network described for most humic substances so far isolated and confirm the presence of IAA in this fraction. The results also show that the LMS fraction of humic substances stimulates the uptake of nitrate by roots and the accumulation of the anion at the leaf level. Moreover, the analysis of the expression of genes encoding two putative maize nitrate transporters (ZmNrt2.1 and ZmNrt1.1) and of two maize H(+)-ATPase isoforms (Mha1 and Mha2) show that these substances may exert direct effects on gene transcription in roots, as shown for the Mha2 gene, and long-distance effects in shoots, as observed for the ZmNrt2.1 gene.
Actins↗
Evaluation of the lipid composition of human healthy and neoplastic renal tissues.
The assumption that kidney tumors are characterized by high lipid content has directed our research towards the evaluation and comparison of lipids in healthy and neoplastic human renal tissues. This research appears to have marked importance owing to the role of lipids in cancer cell biochemistry. Nuclear Magnetic Resonance spectroscopy and chromatographic methods allow the full description of the lipidic profile typical of intact medulla, intact cortex, clear-cell renal carcinomas, chromophobe-cell renal carcinomas, oncocytomas and two samples of medulla infiltrated by a nephrocarcinoma. Significant differences among healthy, benign and malignant tissues were shown, and the results were discussed in relation to the different roles of each lipidic component and compared with the literature data.
Adenoma, Oxyphilic↗
Biochemical characterization of human brain and kidney tissues by magnetic resonance spectroscopy.
In vivo and in vitro Magnetic Resonance Spectroscopy is useful for monitoring changes in intracellular metabolites of human cerebral and renal tissues. Healthy and tumoral tissues of different histologic types have been characterized from a biochemical point of view. In vitro molecular characterization is performed on both the aqueous and lipid extracts of surgically removed tissue biopsies, after in vivo MRS, yielding a full picture of tissue biochemistry. Biochemical markers of healthy brain and kidney and of their relative neoplastic lesions have been disclosed. Moreover, some biochemical features can differentiate neoplasm within the same histological type. Ex vivo MRS also gives molecular information related to necrotic phenomena in glial tumors. MRS finding paralleled histologic data and new knowledge about the molecular base of proliferative neoplastic phenomena can be obtained.
Biochemistry↗
Fast NMR evaluation of lipids in human tissues.
1H and 13C NMR spectroscopy was used to evaluate the degree of unsaturation and the cholesterol/cholesteryl ester ratio on the total lipid fractions obtained from human renal and cerebral tissues. The unsaturated/saturated fatty acid ratio was determined in the 13C NMR spectra from the ratio of the integrated areas of the resonances at 14.13 and 14.17 ppm assigned to the terminal methyl groups of saturated and unsaturated FA, respectively, and is validated by the traditional but time consuming gas-chromatographic analysis. Cholesteryl esters are easily discriminated in the total lipid fraction extracted from human tissues by means of the well-resolved component at 0.99 ppm (1H NMR spectra) of the resonance at about 1.00 ppm generally assigned to free cholesterol. The role of NMR spectroscopy in the study of lipidic biochemistry of human tissues is confirmed.
Brain Chemistry↗
Magnetic resonance spectroscopy and high performance liquid chromatography of neoplastic human renal tissues.
BACKGROUND: The biochemical composition of human neoplastic and normal renal tissues. MATERIALS AND METHODS: Thirteen patients with nephrocarcinomas were examined: 24 samples, 13 from the nephrocarcinomas, 9 from the surrounding healthy parenchyma and 2 from the healthy cortex and medulla were extracted and analyzed by Magnetic Resonance Spectroscopy (MRS) and High Performance Liquid Chromatography (HPLC). RESULTS: MRS yielded information on renal osmolytes, whereas HPLC disclosed the amino acid pattern of tissue extracts. Significant biochemical differences were found between normal and pathological renal tissues: the osmolyte content decreases dramatically in nephrocarcinomas. CONCLUSION: We confirm that many osmolytes are present in the healthy kidney, with a different distribution between cortex and medulla, and can be considered markers of a physiological renal function. The marked decrease of these osmolytes is typical of cancer. A detailed knowledge of the biochemical composition of human renal tissues is required for the use of diagnostic methods, like in vivo MRS, the reliability of which is based on the detection of molecular markers. Useful information can also be obtained from the study of the amino acidic fraction.
3-Hydroxybutyric Acid↗