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Neurological insults affect both, brain structure and behavior. The injury-induced brain plasticity and associated changes in behavior are difficult to study using classical histological methods. The magnetic resonance imaging (MRI), however, enables repeated inspection of the brain in the same individual. Here we took advantage of the songbird model with discrete brain circuitry controlling song learning and production and assessed if a conventional MRI is suitable to detect even relatively small brain changes. Our aim was to monitor injury and the following regeneration in the striatal vocal nucleus Area X that controls vocal learning in juveniles and affects song in adult songbird zebra finch (Taeniopygia guttata). The regeneration process was detected using T2-weighted images and validated by immunohistochemical (IHC) staining up to 6 months after the injury. Despite the small volume of the zebra finch brain, a satisfactory signal-to-noise ratio was achieved with reasonably short measurement times. No significant difference was found between the measurements of the lesion size obtained by MRI and IHC staining. Our data show that the non-invasive MRI technique can reliably measure and quantify the regeneration process even in a relatively small part of the brain and that the avian striatum progressively regenerates after its neurotoxic injury.

Songbirds, like humans, learn vocalizations and their striatum recruits new neurons in adulthood. Injury in striatal vocal nucleus Area X, involved in song learning and production in songbirds, is followed by massive regeneration. The newborn neurons arise from the subventricular zone (SVZ) rich in dopamine D3 receptors (D3Rs). The aim of this study was to investigate whether the D3Rs affect the rate of neuronal recovery in Area X. Male zebra finches (Taeniopygia guttata) received bilateral neurotoxic lesion of Area X and were implanted with osmotic minipumps containing D3R agonist 7-OH-DPAT, antagonist U99194, or saline. Treatment with 7-OH-DPAT but not U99194 led to significant reduction of lesion size and increased numbers of migrating neuroblasts and newborn cells in the Area X. These cells were detected in the lesion border as well as the lesion center. Lesion also led to increased mRNA expression of the D3Rs in the neurogenic SVZ and in the nucleus robustus arcopallialis (RA) involved in song production. Moreover, lesion alone prolonged the song duration and this may be facilitated by D3Rs in RA. Parallel lesion and stimulation of D3Rs prolonged it even more, while blocking of D3Rs abolished the lesion-induced effect. These data suggest that D3R stimulation after striatal injury accelerates the striatal recovery and can cause behavioral alterations.

Alzheimer's disease (AD) is the most common form of dementia. It is a degenerative, incurable and terminal disease. The increasing prevalence of AD is, among other reasons, due to population aging, which is, to a certain extent, seen worldwide. Continuous advances in health care keep increasing life expectancy. Official statistics are likely to significantly underestimate the actual prevalence of AD. Alzheimer's disease represents an important public health problem. Its aetiology is still unknown and for this reason, it is necessary to study all potential risk factors which may contribute to the development of this disease.We searched original and review articles addressing Alzheimer's disease using key words Alzheimer's disease, epidemiology, risk factors and prevention. We found and used one hundred and four references.Based on epidemiological studies, genetic studies, neuroimaging methods and neuropathology research, three basic etiological hypotheses of the development of AD have been formulated: genetic, vascular and psychosocial. At present, the level of evidence is insufficient for the etiological role of other factors, such as nutrition, occupational exposure to various substances and inflammation. From the point of view of early diagnosis and application of primary or secondary prevention principles, genetic factors are the most important.

We analyse the multifractal structure of moments Gq in terms of a new variable X on data of 197Au, 32S and 16O induced interactions with emulsion nuclei and Monte Carlo generated samples. The dynamical properties of the produced particles are mapped onto multifractal spectra. We compare ln G in experimental data of 197Au, 32S and 16O with pure statistical fluctuations. It is shown that the stochasticity plays an important role for the G-moments.

The anomalous behavior of 2-dimensional factorial moment in nucleus-nucleus collisions is studied in some detail using both mini-bias and central collision data of ^{16}O-, ^{32}S- and ^{197}Au-Em interactions from EMU01 experiment. The correct value for the effective Hurst exponent in the analysis of higher-dimensional factorial moment is found to be greater than unity, showing clearly the existence of superposition effect in nucleus-nucleus collisions. The anomalous behavior of 2-dimensional factorial moment in nucleus-nucleus collisions is studied in some detail using both mini-bias and central collision data of ~{16}O-, ~{32}S- and ~{197}Au-Em interactions from EMU01 experiment. The correct value for the effective Hurst exponent in the analysis of higher-dimensional factorial moment is found to be greater than unity, showing clearly the existence of superposition effect in nucleus-nucleus collisions. The anomalous behavior of 2-dimensional factorial moment in nucleus-nucleus collisions is studied in some detail using both mini-bias and central collision data of ~{16}O-, ~{32}S- and ~{197}Au-Em interactions from EMU01 experiment. The correct value for the effective Hurst exponent in the analysis of higher-dimensional factorial moment is found to be greater than unity, showing clearly the existence of superposition effect in nucleus-nucleus collisions. The anomalous behavior of 2-dimensional factorial moment in nucleus-nucleus collisions is studied in some detail using both mini-bias and central collision data of ~{16}O-, ~{32}S- and ~{197}Au-Em interactions from EMU01 experiment. The correct value for the effective Hurst exponent in the analysis of higher-dimensional factorial moment is found to be greater than unity, showing clearly the existence of superposition effect in nucleus-nucleus collisions. The anomalous behavior of 2-dimensional factorial moment in nucleus-nucleus collisions is studied in some detail using both mini-bias and central collision data of ~{16}O-, ~{32}S- and ~{197}Au-Em interactions from EMU01 experiment. The correct value for the effective Hurst exponent in the analysis of higher-dimensional factorial moment is found to be greater than unity, showing clearly the existence of superposition effect in nucleus-nucleus collisions. The anomalous behavior of 2-dimensional factorial moment in nucleus-nucleus collisions is studied in some detail using both mini-bias and central collision data of ~{16}O-, ~{32}S- and ~{197}Au-Em interactions from EMU01 experiment. The correct value for the effective Hurst exponent in the analysis of higher-dimensional factorial moment is found to be greater than unity, showing clearly the existence of superposition effect in nucleus-nucleus collisions. The anomalous behavior of 2-dimensional factorial moment in nucleus-nucleus collisions is studied in some detail using both mini-bias and central collision data of ~{16}O-, ~{32}S- and ~{197}Au-Em interactions from EMU01 experiment. The correct value for the effective Hurst exponent in the analysis of higher-dimensional factorial moment is found to be greater than unity, showing clearly the existence of superposition effect in nucleus-nucleus collisions. The anomalous behavior of 2-dimensional factorial moment in nucleus-nucleus collisions is studied in some detail using both mini-bias and central collision data of ~{16}O-, ~{32}S- and ~{197}Au-Em interactions from EMU01 experiment. The correct value for the effective Hurst exponent in the analysis of higher-dimensional factorial moment is found to be greater than unity, showing clearly the existence of superposition effect in nucleus-nucleus collisions. The anomalous behavior of 2-dimensional factorial moment in nucleus-nucleus collisions is studied in some detail using both mini-bias and central collision data of ~{16}O-, ~{32}S- and ~{197}Au-Em interactions from EMU01 experiment. The correct value for the effective Hurst exponent in the analysis of higher-dimensional factorial moment is found to be greater than unity, showing clearly the existence of superposition effect in nucleus-nucleus collisions. The anomalous behavior of 2-dimensional factorial moment in nucleus-nucleus collisions is studied in some detail using both mini-bias and central collision data of ^{16}O-, ^{32}S- and ^{197}Au-Em interactions from EMU01 experiment. The correct value for the effective Hurst exponent in the analysis of higher-dimensional factorial moment is found to be greater than unity, showing clearly the existence of superposition effect in nucleus-nucleus collisions.

Inelastic interactions induced by84Kr nuclei at 800–950 MeV/nucleon have been studied using a high angular resolution emulsion detector. Data on multiplicities of the produced particles, projectile and target fragments are shown. Comparisons with cascade calculations have been performed.

Fe-, Kr- and Xe-induced heavy-ion reactions at ~ 1 A GeV show factorization in the production cross-sections only for light fragments. Both "strong" and "weak" factorization are found for light fragments. The cross-sections of these fragments are described in detail within the prescription of cold breakup of spectator residues.

M. xenopi was definitely demonstrated 14 times in the sputum of a 70-year-old man with chronic obstructive lung disease. Sputum conversion was achieved by combined chemotherapy, but the patient died of cor pulmonale and associated terminal pneumonia. Autopsy revealed moderately advanced old fibrotic pulmonary lesions of tuberculous origin including a large "open healed" cavity, and recent involvement of lymphatic nodules with a bronchonodular fistula accompanied by dispersed lesions in the surrounding pulmonary tissue. Culture of the latter lesions yielded M. xenopi and were formed by central necrosis with numerous acid-fast rods surrounded by a hyaline capsule without any specific or nonspecific inflammation. No histological differences were detected between these lesions and lesions from a disease provoked by M. tuberculosis.

Using emulsion detectors a transverse-momentum analysis of projectile fragments has been performed in Au induced nuclear interactions at 11.6 A GeV/c. Evidence for collective flow of the projectile fragments has been obtained. Angular distributions of the principal vectors of projectile and target fragments have shown strong azimuthal correlation.

Angular distributions of projectile-associated He fragments from Pb induced reactions on stationary Pb target at 158 A GeV/c incident momentum are reported. The precision of the angular measurements was about ±0.01 mrad. Two emission components are appearing in the projected angular spectra of the He particles, one representing fragmentation at Fermi momentum scale, while the other one exhibits large transverse momentum transfer. By scaling with the incident momentum the angular spectra of He particles are compared with earlier reported measurements of Au on Au interactions at 11.6 A GeV/c. The p T spectrum of the He particles appears the same for the two cases.