A comparison between in vivo and ex vivo HR-MAS H-1 MR spectra of a pediatric posterior fossa lesion

The present case report was aimed at identifying the molecular profile characteristic of a primitive neuroectodermal tumor (PNET) in a 3-year-old child affected by a lesion localized in the cerebellar region. The histological diagnosis was medulloblastoma. In vivo single voxel H-1 magnetic resonance spectroscopy (MRS) shows high specificity in detecting the main metabolic alterations in the primitive cerebellar lesion; a very high amount of the choline-containing compounds and very low level of creatine derivatives and N-acetylaspartate. Ex vivo high resolution magic angle spinning (HR-MAS) H-1 magnetic resonance spectroscopy, performed at 9.4 Tesla on the neoplastic specimen collected during surgery, allows for the unambiguous identification of several metabolites giving a more in-depth evaluation of the metabolic pattern of the lesion. The ex vivo HR-MAS MR spectra show that the spectral detail is much higher than that obtained in vivo and that, for example, myo-inositol, taurine and phosphorylethanolamine contribute to the in vivo signal at 3.2 ppm, usually attributed to choline-containing compounds. In addition, the spectroscopic data appear to correlate with some morphological features of the medulloblastoma. Consequently, the present study shows that ex vivo HR-MAS H-1 MRS is able to strongly improve the clinical possibility of in vivo MRS and can be used in conjunction with in vivo spectroscopy for clinical purposes

Proton NMR characterization of intact primary and metastatic melanoma cells in 2D & 3D cultures

Abstract Objective To characterize the differences between the primary and metastatic melanoma cell lines grown in 2D cultures and 3D cultures. Methods Primary melanoma cells (WM115) and metastatic melanoma cells (WM266) extracted from a single donor was cultured in 2D as well as 3D cultures. These cells were characterized using proton NMR spectrometry, and the qualitative chemical shifts markers were identified and discussed. Results In monolayer culture (2D), we observed one qualitative chemical shift marker for primary melanoma cells. In spheroid cultures (3D), we observed nine significant chemical shifts, of which eight markers were specific for primary melanoma spheroids, whereas the other one marker was specific to metastatic melanoma spheroids. This study suggests that the glucose accumulation and phospholipid composition vary significantly between the primary and metastatic cells lines that are obtained from a single donor and also with the cell culturing methods. 14 qualitative chemical shift markers were obtained in the comparison between monolayer culture and spheroids cultures irrespective of the differences in the cell lines. Among which 4 were unique to monolayer cultures whereas 10 chemical shifts were unique to the spheroid cultures. This study also shows that the method of cell culture would drastically affect the phospholipid composition of the cells and also depicts that the cells in spheroid culture closely resembles the cells in vivo. Conclusion This study shows the high specificity of proton NMR spectrometry in characterizing cancer cell lines and also shows the variations in the glucose accumulation and phospholipid composition between the primary and metastatic melanoma cell lines from the same donor. Differences in the cell culture method does plays an important role in phospholipid composition of the cells

Sguardi nei contesti quotidiani: ripensando spazi, arredi, materiali

E' uno spazio ricco di funzioni e di 'dimensioni' quello del nido, la cui osservazione svela intenzioni educative, possibilit\ue0 e limiti. Esiste una 'Pedagogia dello spazio' e della sua materialit\ue0 che dovrebbe far parte della competenza dell'educatrice

PKA DETERMINATION OF THE DEOXYDINUCLEOTIDE MONOPHOSPHATE CA AND OF THE CORRESPONDING HEXANUCLEOTIDE CACACA BY INVERSE-DETECTED C-13 NMR

The pK(a) values of adenine N1 and cytosine N3 in the non-self complementary title compounds have been measured by C-13 NMR, using an inverse probe. in the deoxydinucleotide adenine N1 has pK(a) = 2.52, markedly smaller than that of cytosine N3 for which pK(a) = 4.42. In the hexanucleotide the pK(a) values of adenine N1 and cytosine N3 are much closer, being 3.97 and 4.67, respectively

A New NMR technique: HR-MAS applied to animal and vegetable soft materials

Nuclear Magnetic Resonance (NMR) Spectroscopy is widely employed for the identification and structural characterization of organic compounds in solution and in the solid state. In this contribution we are going to show some recent applications of a new NMR technique, namely High Resolution-Magic Angle Spinning (HR-MAS), to soft materials, in particular to porcine and veal meat, and to citrus lemon. HR-MAS technique can be considered a hybrid technique between solid-state and classical solution-state NMR. Dedicated HR-MAS probes permit to perform one-dimensional and two-dimensional (1D and 2D) correlation experiments, analogue to those commonly applied in solution, on semisolid samples, and to detect signals from metabolites and macromolecules

MONO AND BIDIMENSIONAL H-1-NMR AND INVERSE-DETECTED C-13 NMR OF THE DUPLEX D(CA)3-CENTER-DOT-D(TG)3

The unambiguous assignment of the aromatic protons of the duplex d(CA)3.d(TG)3 was carried out with the aid of HMQC and HMBC inverse detected C-13 NMR experiments at T = 278 K. The NOE connections of these protons with the imino protons of the complementary bases - established by 2D NOESY experiments - indicated that the duplex is characterized by a canonical Watson-Crick base-pairing pattern. Monodimensional H-1 NMR experiments, also carried out at T = 278 K, in the presence of varying amounts of NaCl and with water suppression by presaturation and by spin echo techniques, showed that the imino protons of the TA and CG pairs of the duplex exchange with water through a process of local base pair opening and with different exchange rates

1H NMR Spectra of Oxiranes, cis-Arylmethyl Oxiranes Substituted in the Phenyl Ring,

NMR spectra of title compound

CONFORMATIONAL AND CONFIGURATIONAL STUDY OF 1,3-DIOXOLANES BY PROTON AND CARBON NMR-SPECTROSCOPY

The configurational and conformational properties of six 4-trimethylammoniummethyl 2,2-disubstituted 1,3-dioxolanes were studied using NOE experiments and vicinal coupling constants. Selective 1D NOE experiments proved to be effective tools in the configurational assignment of C-2 relative to C-4, The preferred conformation of the dioxolane ring and the exocyclic group at C-4 was obtained by employing vicinal coupling constants and NOE results. The H-1 and C-13 NMR chemical shifts show stereochemically dependent trends, Quantitative analysis of conformer populations was performed using Haasnoot et al's equation. The -N+(CH3)(3) group was found to be synclinal with respect to the heterocyclic 0-3 atom and points outside the ring, When a phenyl group is present at C-2, the 4-CH2N+ - group in a trans relationship to the 2-phenyl ring was found to occur prevalently in a pseudo-axial orientation, whereas it was established to be prevalently pseudo-equatorial when cis with respect to the phenyl ring

La RMN ex vivo di neoplasie umane: aspetti biochimici e considerazioni cliniche.

L'individuazione di indicatori biochimici di stati funzionali e/o patologici \ue8 un requisito fondamentale per lo sviluppo di moderne metodiche diagnostiche quali la spettroscopia di risonanza magnetica nucleare eseguita direttamente sul paziente (in vivo RMN). La in vivo RMN consiste nella combinazione della risonanza magnetica per immagini per la localizzazione di un volume di interesse dell'organo da esaminare e della spettroscopia per la determinazione dei metaboliti in esso contenuti. La tecnica \ue8 estremamente sensibile e specifica nel rilevare le variazioni metaboliche che si accompagnano a determinate patologie ed esprime grandi potenzialit\ue0 nell'aggi ungere nuove opportunit\ue0 nella valutazione clinica di diverse malattie umane, comprese le neoplasie. Tessuti e organi umani funzionali e patologici possono cos\uec essere valutati, in modo assolutamente non invasivo, per quanto riguarda le loro caratteristiche biochimiche, secondo quelli che sono gli indirizzi di una moderna diagnostica molecolare. Nonostante numerosi studi in letteratura evidenzino come la in vivo RMN sia oggi utilizzata, a supporto delle tradizionali ma invasive metodiche istopatologiche, nella valutazione clinica (diagnosi, trattamento e prognosi) di numerose neoplasie umane (cervello, seno e prostata principalmente), sono ancora di grande attualit\ue0 studi finalizzati alla caratterizzazione delle principali caratteristiche molecolari associate alle neoplasie cerebrali in funzione del loro tipo e grado istologico. Inoltre vi sono tessuti quali quelli della mucosa gastro-intestinale per i quali le applicazioni della in vivo RMN sono ancora in una fase di studio preliminare. Per aumentare le possibilit\ue0 cliniche della in vivo RMN si rendono cos\uec necessarie sempre pi\uf9 approfondite ricerche mirate ad una dettagliata descrizione della composizione biochimica dei tessuti e che consentono di individuare le correlazioni fra indicatori molecolari della patologia e gli aspetti morfologici che concorrono a definire non solo il tipo di neoplasia, ma anche il suo grading, con evidenti implicazioni diagnostiche e prognostiche