High resolution hard X-ray 3D mapping of a Macaca fascicularis eye: A feasibility study without contrast agents.

Several complementary methods able to visualize the internal structures of eyes are used in the clinical practice in the diagnosis of pathologies affecting a specific zone of the eye. Despite the significant technological progress, the visualization of the entire eyeball at micrometric resolution is yet an unsolved task both in clinical diagnostics and in laboratory research. With this respect, high resolution 3D images of the eyeball would be extremely useful, in the study of various pathologies of the retina, the lens, and of the optic nerve. In this work we combined the state-of-the-art of micro computed tomography technology with phase-contrast imaging, a recent highly sensitive technique well adapted to investigate soft tissues without the use of contrast agents; we applied the technique in the post-mortem analysis of monkey eyes, which share several similitudes with the human organ. We reported here vascular, nervous and anatomical details of monkey eyes imaged with a 3.1 × 3.1 × 3.1 µm3 voxel size as well as the first 3D visualisation of the entire globe of Macaca's fascicularis eye. Results have also been compared with, and validated by, histological analysis.

[THE EFFECT OF NEUROPEPTIDE Y ON SPIKE ACTIVITY OF NEURONS IN THE SUPRACHIASMATIC NUCLEUS OF RAT IN VITRO].

In the experiments on sagittal hypothalamic slices of male Wistar rats, the effect of 10 nM neuropeptide Y on the electrical activity of the suprachiasmatic nucleus neurons and spike information coding parameters were studied. Applications of neuropeptide Y induced a reduction of action potential frequency in 35 of 81 tested neurons, in 8 cells an increase in the parameter was observed; the remaining 38 neurons did not change their spike activity level. The decrease in spike frequency generation by neurons of the suprachiasmatic nucleus accompanied by an increase in both entropy of interspike interval distribution and mutual information between adjacent interspike intervals. These suggest an increased irregularity of the later as well as an increased patterning of spike information induced by neuropeptide Y. The obtained data indicate the ability of neuropeptide Y to modulate a level of activity and influence a spike code in a relatively numerous population of neurons in circadian oscillator of the suprachiasmatic nucleus.

[Use of dispersion analysis for comparative evaluation of the effect of several factors on the frequency of secondary cases in foci of dysentery]. / Primenenie dispersionnogo analiza dlia sravnitel'noi otsenki vliianiia nekotorykh faktorov na chastotu vtorichnykh sluchaev v ochagakh dizenterii

The author demonstrates a method of application of dispersion analysis in epidemiological studies. The results of this work emphasize the leading role of the living-communal conditions in the appearance of repeated cases in the dysentery foci.

[Evaluation of the epidemiological effectiveness of hospitalization of patients with dysentery]. / K otsenke épidemiologichesko éffektivnosti gospitalizatsii bol'nykh dizenteriei

The authors present materials on the study of epidemiological efficacy of hospitalization of dysentery patients by statistical analysis (calculation of tendencies, rates of increase, etc.) of the indices of focal morbidity per 1000 contacts in the total number of foci characterized by various periods of isolation of the first patient. The work was carried out on materials of two towns considerably differing by the extent of organization of public services and amenities. The results obtained pointed to the relative epidemiological efficacy of hospitalization of dysentery patients particularly marked at the territory with less favourable living conditions.