The diffusion-tensor imaging reveals alterations in water diffusion parameters in acute pediatric concussion.

Wide-spread visualization methods which are computed tomography (CT) and magnetic resonance imaging (MRI) are not sensitive to mild traumatic brain injury (mTBI). However, mTBI may cause changes of cerebral microstructure that could be found using diffusion-tensor imaging. The aim of this study is to reveal the impact of acute mTBI (no more than 3 days after trauma) on diffusion parameters in corpus callosum, corticospinal tract, and thalamus in children (aged 14-18). Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were analyzed. Significant increase in FA and decrease in ADC were observed in thalamus. The trend to an increase in FA is observed in corpus callosum.

MRI Study for the Features of Brain Conduction Pathways in Patients with an Ultra-High Risk of Endogenous Psychoses.

Diffusion parameters of brain tracts (n=18) were studied in 27 men with ultra-high risk of endogenous attack-like psychoses and 27 mentally healthy men of the same age group (fractional anisotropy; and average, radial, and axial diffusion). Correlation analysis was performed between these parameters and severity of mental disorders (SOPS scale). The indexes of radial diffusion and axial diffusion were shown to change in the left anterior thalamic radiation and right posterior cingulum bundle, respectively. Our results are consistent with published data that disturbances in the frontal and temporal lobes play an important role in the pathogenesis of schizophrenia. The degree of mental disorders correlated with diffusion parameters in the left and right anterior cingulum bundle.

(1)H-MRS and MEGA-PRESS pulse sequence in the study of balance of inhibitory and excitatory neurotransmitters in the human brain of ultra-high risk of schizophrenia patients.

The MEGA-PRESS pulse sequence was used for determination of overlapping signals in the (1)H-MRS spectra of the human brain. For the first time, the balance of GABA glutamate/glutamine concentrations was estimated quantitatively in the human brain of patients with ultra-high risk of schizophrenia. It was found that GABA concentration and GABA/GLX ratios were significantly reduced in the left frontal lobe of UHR subjects.

[Information processing and brain metabolic characteristics in patients at ultra-high risk for endogenous psychosis].

OBJECTIVE: Functional and structural brain abnormalities in people at high risk for psychosis is a subject of intensive studies in biological psychiatry over the last decades. We studied correlations between neurophysiological and neuroimaging parameters in ultra-high risk patients. MATERIAL AND METHODS: Fifty-six patients, aged 17-25 years, with nonpsychotic mental disorders were examined. The control group included 30 age- and sex-matched healthy people. Neurophysiological study measured sensory gating. Proton MR-spectroscopy was used to study metabolic processes in the brain (index for glutamate/glutamine, N-acetylaspartate and choline containing compounds in the dorsolateral prefrontal cortex and thalamus of both hemispheres as well as in the genu and splenium of the corpus callosum). RESULTS AND CONCLUSION: We found the abnormality of sensory gating in patients at ultra-high risk for endogenous psychosis that was not correlated with the metabolic parameters. The latter were normal or were normalized during treatment.

31P NMR in vivo study of rat brain energy metabolism after frontal cortex injury. A method based on convoluted correlation matrices of the spectral data.

Disturbances of energy metabolism in rat brain after frontal lobectomy and post-traumatic effects of monosialic ganglioside GM1 on brain energy metabolism were studied by 31P NMR in vivo. Frontal lobectomy caused the statistically significant reversible decrease of ATP and increase of ADP during the compensatory period. In a presence of GM1 these post-operational effects were not observed. The mean value of normalized correlation coefficients between NMR-measured phosphomonoesters, P(i), pH, phosphocreatine, gamma-ATP + beta-ADP, alpha-ATP + alpha-ADP +NAD/NADH + diphosphodiesters and beta-ATP for a given group of animals (Z-index) was used to estimate brain energetic status. It has been shown that the variation of the Z-index correlates with the dynamics of locomotor activity during the compensatory period. The Z-index increased by more than 100% for the subgroup with an increased moving activity and only by about 20% for the subgroup with a decreased activity. Moreover, the compositions of these subgroups were almost the same as those from the solution of the reverse task, i.e., the studied group was divided into two subgroups by the Z-index. The Z-index is proposed as a possible criterion of pathology detection in brain energetics.

The involvement of fructose 2,6-bisphosphate in substrate cycle control in the nonoxidative stage of the pentose phosphate pathway. A phosphorus magnetic resonance spectroscopy study.

The role of fructose 2,6-bisphosphate in the interconversion of sedoheptulose 7-phosphate and sedoheptulose 1,7-bisphosphate in rat liver cytosol fractions was studied by means of phosphorus magnetic resonance spectroscopy. When the activity of 6-phosphofructo-1-kinase was inhibited by a high concentration of ATP, the addition of fructose 2,6-bisphosphate led to a marked decrease in sedoheptulose 7-phosphate levels, accompanied by an increased concentration of ADP. Fructose 2,6-bisphosphate essentially inhibited both the decrease in sedoheptulose 1,7-bisphosphate concentration and the accumulation of Pi in the incubation mixture. The data provided evidence that fructose 2,6-bisphosphate can regulate the substrate cycle: sedoheptulose 7-phosphate<-->sedoheptulose 1,7-bisphosphate in the liver, and thus control the flux through the nonoxidative stage of the pentose phosphate pathway.

[Prognostically significant indices of the bioenergetic metabolism of the brain in experimental ischemia (a NMR spectroscopic study)]. / Nekotorye prognosticheski znachimye pokazateli bioénergeticheskogo metabolizma mozga pri ego ishemii v éksperimente (IaMR-spektroskopicheskoe issledovanie).

Initial levels of phosphate brain metabolites were measured using 31P NMR spectroscopy in rats which subsequently died or survived under bilateral ligation of common carotid arteries. A multidimensional analysis was applied. In the rats which died after the brain ischemia: (1), NAD and NADH+ concentrations were much higher than those of creatine phosphate or ATP (i.e. baseline dysbalance existed between the systems of hydrogen acceptors and major macroergic substances); (2), the force of relationships between parameters of NMR spectra in each correlation matrix were 10 times higher and the variability of elements in each matrix was significantly lower than those of the surviving group. These regularities can be used in detection of special groups at high professional risk and in designing individual procedures of prevention and treatment of cerebral circulation disorders. The data are valuable in terms of development of drugs which would correct the dysbalance between hydrogen acceptors and macroergic systems thus providing a metabolic defense for the ischemic brain.

[Phosphorus-containing metabolites in the cells of anthracycline-resistant strains of leukemia P388]. / Issledovanie fosforsoderzhashchikh metabolitov v kletkakh antratsiklinustoichivykh shtammov leikoza P388.

The method of 31P nuclear magnetic resonance has been used to study in vivo the level of phosphorus-containing metabolites in cells of two strains of murine leukemia P388 with the phenotype of the multidrug resistance and in cells of the parent strain. Cells of both resistant strains showed a depressed level of phosphomonoesters in comparison with the parent one. The influence of rubomycin and emoksil on the level of phosphorus-containing metabolites of drug-resistant and -sensitive strains has been evaluated. The drugs were established not to affect practically the pool of these metabolites of the resistant strains. Both drugs significantly increased the pool of phosphomonoesters in the parent strain cells.

[The effect of verapamil on the dynamics of decrease in the brain levels of phosphorus macroergs during ischemia studied by 31P-NMR in vivo]. / Vliianie verapamila na dinamiku snizheniia urovnei makroérgicheskikhfosfatov mozga pri ishemii po dannym 31P-IaMR spektroskopii in vivo.

Protective effects of verapamil on dynamics of phosphorus-containing metabolites were studied during 30 min complete ischemia by means of 31P NMR. Verapamil appears to decrease the ATP and creatine phosphate pools consumption in ischemic brain tissue. The efficiency of the drug depended on the administration procedure and was not similar in two different models of ischemia. Possible mechanisms of the verapamil effect on bioenergetics of nervous tissue are discussed.