Glutathione and a Pool of Metabolites Partly Related to Oxidative Stress Are Associated with Low and High Myopia in an Altered Bioenergetic Environment.

Oxidative stress forms part of the molecular basis contributing to the development and manifestation of myopia, a refractive error with associated pathology that is increasingly prevalent worldwide and that subsequently leads to an upsurge in degenerative visual impairment due to conditions that are especially associated with high myopia. The purpose of our study was to examine the interrelation of potential oxidative-stress-related metabolites found in the aqueous humor of high-myopic, low-myopic, and non-myopic patients within a clinical study. We conducted a cross-sectional study, selecting two sets of patients undergoing cataract surgery.

Quantification of HO by H-MR imaging at 3 T: a feasibility study.

Background: Indirect H-magnetic resonance (MR) imaging of O-labelled water allows imaging in vivo dynamic changes in water compartmentalisation. Our aim was to describe the feasibility of indirect H-MR methods to evaluate the effect of HO on the MR relaxation rates by using conventional a 3-T equipment and voxel-wise relaxation rates.

Methods: MR images were used to calculate the R1, R2, and R2* relaxation rates in phantoms (19 vials with different HO concentrations, ranging from 0.

Magnetic resonance spectroscopy and imaging on fresh human brain tumor biopsies at microscopic resolution.

The metabolic composition and concentration knowledge provided by magnetic resonance spectroscopy (MRS) liquid and high-resolution magic angle spinning spectroscopy (HR-MAS) has a relevant impact in clinical practice during magnetic resonance imaging (MRI) monitoring of human tumors. In addition, the combination of morphological and chemical information by MRI and MRS has been particularly useful for diagnosis and prognosis of tumor evolution. MRI spatial resolution reachable in human beings is limited for safety reasons and the demanding necessary conditions are only applicable on experimental model animals.

Development of a three-dimensional cell culture system based on microfluidics for nuclear magnetic resonance and optical monitoring.

A new microfluidic cell culture device compatible with real-time nuclear magnetic resonance (NMR) is presented here. The intended application is the long-term monitoring of 3D cell cultures by several techniques. The system has been designed to fit inside commercially available NMR equipment to obtain maximum readout resolution when working with small samples.

Study of the inferior colliculus in patients with schizophrenia by magnetic resonance spectroscopy.

INTRODUCTION. Previous studies have suggested morphometric and functional abnormalities in the inferior colliculus in patients with schizophrenia. Auditory hallucinations are one of the central symptoms in schizophrenia.

Strategies for annotation and curation of translational databases: the eTUMOUR project.

The eTUMOUR (eT) multi-centre project gathered in vivo and ex vivo magnetic resonance (MR) data, as well as transcriptomic and clinical information from brain tumour patients, with the purpose of improving the diagnostic and prognostic evaluation of future patients. In order to carry this out, among other work, a database--the eTDB--was developed. In addition to complex permission rules and software and management quality control (QC), it was necessary to develop anonymization, processing and data visualization tools for the data uploaded.

Accurate classification of childhood brain tumours by in vivo ¹H MRS - a multi-centre study.

Aims: To evaluate the accuracy of single-voxel Magnetic Resonance Spectroscopy ((1)H MRS) as a non-invasive diagnostic aid for paediatric brain tumours in a multi-national study. Our hypotheses are (1) that automated classification based on (1)H MRS provides an accurate non-invasive diagnosis in multi-centre datasets and (2) using a protocol which increases the metabolite information improves the diagnostic accuracy.

Methods: Seventy-eight patients under 16 years old with histologically proven brain tumours from 10 international centres were investigated.

Use of 1H and 31P HRMAS to evaluate the relationship between quantitative alterations in metabolite concentrations and tissue features in human brain tumour biopsies.

Quantitative multinuclear high-resolution magic angle spinning was performed in order to determine the tissue pH values of and the absolute metabolite concentrations in 33 samples of human brain tumour tissue. Metabolite concentrations were quantified by 1D (1)H and (31)P HRMAS using the electronic reference to in vivo concentrations (ERETIC) synthetic signal. (1)H-(1)H homonuclear and (1)H-(31)P heteronuclear correlation experiments enabled the direct assessment of the (1)H-(31)P spin systems for signals that suffered from overlapping in the 1D (1)H spectra, and linked the information present in the 1D (1)H and (31)P spectra.

Incremental Gaussian Discriminant Analysis based on Graybill and Deal weighted combination of estimators for brain tumour diagnosis.

In the last decade, machine learning (ML) techniques have been used for developing classifiers for automatic brain tumour diagnosis. However, the development of these ML models rely on a unique training set and learning stops once this set has been processed. Training these classifiers requires a representative amount of data, but the gathering, preprocess, and validation of samples is expensive and time-consuming.

Compatibility between 3T 1H SV-MRS data and automatic brain tumour diagnosis support systems based on databases of 1.5T 1H SV-MRS spectra.

Object: This study demonstrates that 3T SV-MRS data can be used with the currently available automatic brain tumour diagnostic classifiers which were trained on databases of 1.5T spectra. This will allow the existing large databases of 1.

Non-negative blind source separation techniques for tumor tissue typing using HR-MAS signals.

Given High Resolution Magic Angle Spinning (HR-MAS) signals from several glioblastoma tumor subjects, the goal is to differentiate between tumor tissue types by separating the different sources that contribute to the profile of each spectrum. Blind source separation techniques are applied for obtaining characteristic profiles for necrosis, high cellular tumor and border tumor tissue, and providing the contribution (abundance) of each tumor tissue to the profile of the spectra. The problem is formulated as a non-negative source separation problem.

Metabolic profile of chronic liver disease by NMR spectroscopy of human biopsies.

Among the different processes occurring during the evolution of liver disease, fibrosis has a predominant role. Liver fibrosis mechanisms are fairly constant irrespective of the underlying etiology. Cirrhosis is the end-stage of this reaction.

Comparative metabolic profiling of paediatric ependymoma, medulloblastoma and pilocytic astrocytoma.

Brain tumours are the most common solid tumours in children and a major cause of childhood mortality. The most common paediatric brain tumours include ependymomas, cerebellar astrocytomas and medulloblastomas. These brain tumours are highly heterogeneous regarding their histology, prognosis and therapeutic response.

Ex vivo high resolution magic angle spinning metabolic profiles describe intratumoral histopathological tissue properties in adult human gliomas.

In gliomas one can observe distinct histopathological tissue properties, such as viable tumor cells, necrotic tissue or regions where the tumor infiltrates normal brain. A first screening between the different intratumoral histopathological tissue properties would greatly assist in correctly diagnosing and prognosing gliomas. The potential of ex vivo high resolution magic angle spinning spectroscopy in characterizing these properties is analyzed and the biochemical differences between necrosis, high cellularity and border tumor regions in adult human gliomas are investigated.

Magnetic resonance microscopy contribution to interpret high-resolution magic angle spinning metabolomic data of human tumor tissue.

HRMAS NMR is considered a valuable technique to obtain detailed metabolic profile of unprocessed tissues. To properly interpret the HRMAS metabolomic results, detailed information of the actual state of the sample inside the rotor is needed. MRM (Magnetic Resonance Microscopy) was applied for obtaining structural and spatially localized metabolic information of the samples inside the HRMAS rotors.

[Quadrature coils for magnetic resonance spectroscopy in the detection of prostate cancer: single voxel acquisition does not improve the diagnostic accuracy of multivoxel images].

Objective: To determine the viability of quadrature coils for detecting prostate cancer using single voxel and multivoxel spectroscopy images.

Material And Methods: We used a quadrature coil on a 1.5T MR scanner to evaluate 23 patients with suspected prostate cancer and prostate specific antigen levels greater than 4ng/ml (mean 12±8ng/ml), independently of findings at digital rectal examination.

Whole-genomic survey of oligodendroglial tumors: correlation between allelic imbalances and gene expression profiles.

Malignant gliomas are the most common subtype of primary central nervous system (CNS) tumors. Their pathological classification, however, remains subjective, stimulating researchers to actively seek objective molecular markers to discover alternative and more reproducible tools for improved subtypification. Herein, we present a global survey of genomic alterations in oligodendroglial tumors (OT).

NMR metabolic profile of human follicular fluid.

The environment of the oocyte during its in vivo maturation consists of follicular fluid (FF) and is surrounded by granulosa cells. The FF is derived from the sanguineous plasma and secretions, synthesised in the follicle wall, that contain a large variety of growth factors, cytokines, amino acids, and other metabolites. These metabolites are presumably involved in the physiology of the oocyte.

New pattern of EGFR amplification in glioblastoma and the relationship of gene copy number with gene expression profile.

Gene amplification is a process that is characterized by an increase in the copy number of a restricted region in a chromosome arm, and is frequently associated with an overexpression of the corresponding amplified gene. Amplified DNA can be organized either as extrachromosomal elements, repeated units at a single locus or scattered throughout the genome. The amplification of the gene for epidermal growth factor receptor (EGFR) is a common finding in glioblastomas and the amplified gene copies appears as double minutes.

Proton magnetic resonance spectroscopy imaging in the study of human brain cancer.

Magnetic resonance spectroscopic imaging (MRSI) is a non-invasive imaging technique that provides metabolic information on brain tumor. This biochemical information can be processed and presented as density maps of several metabolites, among them N-acetylaspartate (marker of neuronal viability), choline (marker of membrane turnover), creatine (related to the energy state of the cells), myo-Inositol (exclusively found in astrocytes), lipids and lactate (observed in necrosis and other pathological processes) which mean relevant information in the context of brain tumors. Thus, this technique is a multiparametrical molecular imaging method that can complete the magnetic resonance imaging (MRI) study enabling the detection of biochemical patterns of different features and aspects of brain tumors.

Loss of heterozygosity at 1p-19q induces a global change in oligodendroglial tumor gene expression.

Oligodendroglial tumors presenting loss of heterozygosity (LOH) at 1p and 19q have been shown to be sensitive to chemotherapy, thus making 1p-19q status testing a key aspect in oligodendroglioma diagnosis and prognosis. Twenty-nine tumor samples (19 oligodendrogliomas, 10 oligoastrocytomas) were analyzed in order to obtain a molecular profile identifying those bearing 1p-19q LOH. Other genomic anomalies usually present in gliomas, such as EGFR amplification, CDKN2A/ARF deletion, 10q LOH and TP53 mutation, were also studied.

Metabolite profiling of fecal water extracts from human colorectal cancer.

Colorectal cancer is the second leading cause of cancer death in developed countries. There is a need for better preventive strategies to improve the outcome of this disease. The increasing availability of high-throughput methodologies opens up new possibilities for screening new markers.

Multiproject-multicenter evaluation of automatic brain tumor classification by magnetic resonance spectroscopy.

Justification: Automatic brain tumor classification by MRS has been under development for more than a decade. Nonetheless, to our knowledge, there are no published evaluations of predictive models with unseen cases that are subsequently acquired in different centers. The multicenter eTUMOUR project (2004-2009), which builds upon previous expertise from the INTERPRET project (2000-2002) has allowed such an evaluation to take place.