Mycosporine-like Amino Acids and Other Phytochemicals Directly Detected by High-Resolution NMR on Klamath (Aphanizomenon flos-aquae) Blue-Green Algae

This study describes for the first time the use of high-resolution nuclear magnetic resonance (NMR) on Klamath (Aphanizomenon flos-aquae, AFA) blue-green algae directly on powder suspension. These algae are considered to be a "superfood", due to their complete nutritional profile that has proved to have important therapeutic effects. The main advantage of NMR spectroscopy is that it permits the detection of a number of metabolites all at once. The Klamath alga metabolome was revealed to be quite complex, and the most peculiar phytochemicals that can be detected directly on algae by NMR are mycosporine-like amino acids (porphyra-334, P334; shinorine, Shi) and low molecular weight glycosides (glyceryl \u3b2-d-galactopyranoside, GalpG; glyceryl 6-amino-6-deoxy-\u3b1-d-glucopyranoside, ADG), all compounds with a high nutraceutical value. The presence of cis-3,4-DhLys was revealed for the first time. This molecule could be involved in the anticancer properties ascribed to AFA

MRS study of meningeal hemangiopericytoma and edema: A comparison with meningothelial meningioma

Intracranial hemangiopericytomas (HPCs) are rare tumors and their radiological appearance resembles that of meningiomas, especially meningothelial meningiomas. To increase the knowledge on the biochemical composition of this type of tumor for better diagnosis and prognosis, we performed a molecular study using ex vivo high resolution magic angle spinning (HR-MAS) magnetic resonance spectroscopy (MRS) perfomed on HPC and peritumoral edematous tissues. Moreover, to help in the discrimination between HPC and meningothelial meningioma we compared the ex vivo HR-MAS spectra of samples from one patient with HPC and 5 patients affected by meningothelial meningioma. Magnetic resonance imaging (MRI), in vivo localized single voxel 1H-MRS was also performed on the same patients prior to surgery and the in vivo and ex vivo MRS spectra were compared. We observed the presence of OH-butyrate, together with glucose in HPC and a low amount of N-acetylaspartate in the edema, that may reflect neuronal alteration responsible for associated epilepsy. Many differences between HPC and meningothelial meningioma were identified. The relative ratios of myo-inositol, glucose and gluthatione with respect to glutamate are higher in HPC compared to meningioma; whereas the relative ratios of creatine, glutamine, alanine, glycine and choline-containing compounds with respect to glutamate are lower in HPC compared to meningioma. These data will be useful to improve the interpretation of in vivo MRS spectra resulting in a more accurate diagnosis of these rare tumors

HR-MAS NMR spectroscopy in the characterization of human tissues: Application to healthy gastric mucosa

The HR-MAS is an ideal technique for the investigation of intact tissue specimens (10-50 mg) and permits the obtainment of spectra with a resolution comparable to that observed in solution in a time that does not exceed a half of an hour for a routine analysis. The potentialities of HR-MAS NMR spectroscopy in the identification of the metabolites characterizing the healthy gastric mucosa are here presented. The direct 1D H-1 NMR spectra enables only few metabolites to be confidently assigned, and the use of selected 2D experiments strongly amplify the analytical effectiveness of the technique

Molecular characterization of human gastric mucosa by HR-MAS Magnetic Resonance Spectroscopy

The present study was aimed at identifying themolecular profile characteristic of the healthy humangastric mucosa.Ex vivo HR-MAS magnetic resonance spectroscopy performed at 9.4 Tesla (400.13 MHz for 1H) on gastric specimens collected during endoscopy, permits the identification of more than forty species giving a detailed picture of the biochemical pattern of the gastric tissues. These preliminary data will be used for a comparison with gastric preneoplastic and neoplastic situations. Moreover, the full knowledge of the biochemical pattern of the healthy gastrictissues is the necessary presupposition for the application of magnetic resonance spectroscopy directly in vivo

Ex vivo HR-MAS Magnetic Resonance Spectroscopy of human gastric adenocarcinomas: A comparison with healthy gastric mucosa

The present study reports the characteristics of the biochemical profile of human gastric adenocarcinoma in comparison with that of healthy gastric mucosa, using ex vivo HR-MAS Magnetic Resonance Spectroscopy. Healthy human mucosa is mainly characterized by the presence of small metabolites (more than 50 identified) and macromolecules, whereas the adenocarcinoma spectra are dominated by the presence of signals due to triglycerides, whose content on the contrary is very low in healthy gastric mucosa. The use of spin-echo experiments enable us to detect some metabolites in the unhealthy tissues and to determine their variation with respect to the healthy ones. We have observed that the Cho:ChoCC ratio changes from 20:80 in the healthy tissues to 80:20 in the neoplastic gastric mucosa

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

Identification of mobile lipids in human cancer tissues by ex vivo diffusion edited HR-MAS MRS

Magnetic Resonance Spectroscopy visible mobilelipids are considered important markers in the diagnosis ofhuman cancer and are thought to be closely involved in variousaspects of tumour transformation, such as cell proliferation,necrosis, apoptosis, hypoxia and drug resistance. A methodallowing the straightforward identification of the lipid classescontributing to the mobile lipids in human malignant tissuesis highly advisable. Ex vivo High Resolution Magic AngleSpinning Magnetic Resonance Spectroscopy was done directlyon human cerebral, renal and colorectal malignant tissuespecimens. A diffusion edited sequence, based on stimulatedecho and bipolar gradient pulses, was used to characterizemolecules with low diffusion rates, arising from mobile lipidcomponents. Cholesterol, triglycerides and phosphatidylcholineare simultaneously detected and all contribute to the mobilelipid resonances present in malignant glioma and clear cellrenal carcinoma tissue specimens spectra. On the contrary,papillary cell renal carcinoma spectrum is predominated byphosphatidylcholine resonances and that of colorectal adenocarcinoma is characterized by signals arising from triglycerides. Ex vivo diffusion edited High Resolution Magic AngleSpinning Magnetic Resonance Spectroscopy, done on intacttissue, is a powerful analytical tool to obtain a simple andimmediate identification of mobile lipid components. This can offer a significant contribution to better understanding their involvement in cancer tissues. Furthermore, ex vivo high resolution spectroscopic measurements allow to improve the interpretation of in vivo Magnetic Resonance spectra, increasing its clinical potentiality

Inverse detection applied to the 1H and 13C assignment and to the regiochemical characterization of beta-substituted alpha,alpha' coupled oligo- and polythiophenes

beta-Substituted alpha-alpha'-coupled oligo- (OTs) and polythiophenes (PTs) are materials currently investigated for their potential applications in optical and electronic devices. beta-Substituents modify both processability and electronic properties with respect to the unsubstituted analogues and these modifications are function not only of the type of substituents but also of their relative positions. When two beta-substituted thiophenes are alpha-alpha' coupled three regiochemically different bithiophenes can be obtained from the three different possible coupling paths: head-to-head, head-to-tail and tail-to-tail. The number of regioisomers enhances in longer oligomers, whereas the interpretation of 1-H and 13-C of PTs is usually based on a four configurational triad model. When the complete 1-H and 13-C assignment and the regiochemical characterisation of OTs and PTs are required, 1-H and 13-C inverse detection proves to be a very powerful tool of investigation. Heteronuclear inverse-detected correlations over one and more bonds are studied and the proton and carbon assignments are often contextual. One-bond correlations are utilised to distinguish between alpha and beta(C,H) pairs, thanks to the different values of alpha and beta 1J(H,C) coupling constantsof thiophene. As far as PTs are concerned, the absence of alpha(C,H) pairs confirms that only alpha,alpha' coupling occurred. Intra-residue correlations over two or three bonds are found running experiments with diffferent evolution delays. When long evolution delays are employed inter-residue correlations are also detected. These last correlations are extremely useful in establishing the thiophene backbone connectivities. Similarly, the association of each beta-substituent to the corresponding ring is found through long-range correlations

HMQC and HMBC Experiments: Useful Tools for the Assignment of the Regiochemistry of Poly(3-Hexylthiophene) through the Unambiguous Characterization of Relative Configurational Diads and Triads

HMQC and HMBC inverse-detection experiments were used for the assignment of the regiochemistry of Poly(3-Hexylthiophene), through the unambiguous characterization of relative configurational diads and triads

Caratterizzazione di politiofeni con tecniche in "inverse detection"

Sono state spiegate le strategie alla base della caratterizzazione dei politiofeni con tecniche in "inverse detection"