Vol 136, No 5 (2009)

he results of sclera investigations from the positions of morphology, physiology, biomechanics and control-system theory, are summarized. The morphological evidence was obtained supporting the physiological hypothesis stating that the specific anatomical organization and spatial displacement of elastic fibercontaining scleral layers against one another, are the key elements in formation of the individual level of intraocular pressure (IOP) in man both under normal and pathological conditions. It was shown that the elastic fibers outlined the collagen lamallae in of scleral internal layers. External scleral layer lacked elastic fibers. Scleral elastic fibers are necessary for the functioning of the mechanism of sclera microfluctuations associated with the intraocular fluid accumulation and removal, they are also important for dampening the sudden changes of IOP. Under normal conditions, age-related increase in scleral rigidity is primarily associated with the process of accelerated aging of its superficial non-elastic layers, resulting in the physiological response of the current IOP level elevation. As IOP becomes elevated under normal conditions, the internal elastic fiber-containing scleral layers are increasingly pressed against more rigid external layer. This limits the displacement capacity of internal layers against each other, resulting in the decline of the efficiency of elastic fiber work in dampening the sudden changes of IOP. In the healthy eyes, the process of scleral aging brings to a natural development of ophthalmohypertension, when IOP elevation is physiologically required for the maintenance of the volume microfluctuation mechanism ("scleral respiration"). In glaucoma, the pathological rearrangement of the scleral fibrous structures is observed, resulting in an additional abrupt increase of its rigidity, with the reciprocal significant elevation of the current level of IOP and the amplitude of its jumps. Pathophysiological mechanism of these significant changes in glaucoma remains currently unknown, however, morphological evidence indicates that it is associated with the changes in the metabolic processes in sclera.

Gliosis is one of the main morphological correlates of epilepsy. It is presented predominantly by proliferation and hypertrophy of astrocytes and activated microglia (macrophages) and is most characteristic to those areas of the epileptogenic zones, where the loss of neurons is significant. One of such structures is the hippocampus, the sclerosis of which develops already at the early stages of epileptogenesis. Using the slides stained with cresylviolet, the quantitative analysis of gliocytes and of macrogliocyte-neuronal ratio was performed in all the areas of the hippocampus 14 and 30 days after electrical kindling. After both time intervals, the decrease of the number of neurons and the increase of the number of gliocytes were found in all the regions of the hippocampus. After 14 days the changes of gliocytes were particularly significant in the radial and oriental layers of the Ammon's horn, after 30 days they were also pronounced in CA3 pyramidal cell layer of and in hilus. Thus, hippocampal gliocytes are actively involved in the epileptogenesis.

Topographic anatomical relationship between the trigeminal nerve trunk (TNT) and superior cerebellar artery (SCA) was investigated in 25 autopsy cases (50 TNTs), in individuals who never suffered from trigeminal neuralgia (TN), by means of injecting colored polymerizing silicone mass into the vertebrobasilar system through one of the vertebral arteries. It was found that the top ol SCA loop (formed as its anterior pontomesencephalic segment continues into the lateral pontomesencephalic segment) was situated between TNT and tentorium ol the cerebellum, and the lateral pontomesencephalic segment did not intersect the TNT in the vertical plane. The contact between SCA pontomesencephalic segment with the superior surface of TNT in the projection of the entry zone and around it was observed in 16 cases (32%). Close proximity between the SCA and TNT (no more than 2 mm) was observed in 12 % ol cases, whilst the distance exceeding 2 mm was observed in 56% ol cases. In 163 patients with TN, the top of the loop of the dolichoectatic SCA was located below TNT, and its distal part (pontomesencephalic segment) crossed TNT in the region of the entry zone or close to it, causing the traumatizing action. In 121 cases (74%), a single SCA branch was involved and in 42 cases (26%) two branches were involved. Thus, these observations have shown that the contact between SCA and TNT cannot lead to TN development, since traumatizing action on the nerve results not from the pulsation of the wall of artery which touches the nerve, but from the strokes of the distal arm of SCA loop, that unbends during each systole and is located at an angle to TNT. This is the essence of the difference between the neurovascular contact and the neurovascular conflict.

The goal of the work was to study the structure of neurons treated with proteases and to elucidate if this could lead to the formation of the interneuronal syncytial connections. In the first series of experiments, phase contrast observation of the living dissociated ganglionic neurons of the mollusc Lymnaea stagnalis treated with 0.4% pronase, demonstrated a retraction of nerve processes and a two-phase change of the cell body volume. At the first stage, the soma volume decreased, on the average, for 82.5 min by 12.1%; subsequently, the volume increased, on average, by 14.1 %. Signs of neuronal vital activity in Ringer's solution were observed, on the average, for 828 min, while in pronase solution their duration was 1.4 times shorter. In the second series of experiments, the study of neuronal ultrastructure has demonstrated in many cases the integrity of mitochondria, rough and smooth endoplasmic reticulum (ER), Golgi complex, light and granular vesicles, nuclear structure, and the preservation of the optical density of neuroplasm. The cells making contacts after centrifugation form uniform intercellular clefts of about 20 nm. Point approaches of membranes were very rare. No signs of syncytial connections were detected. Elongation and fusion of smooth ER cisterns separated the fragments of soma from relatively undamaged cells. Some neurons were damaged, they contained numerous vacuoles formed by swollen mitochondria and ER cisterns. The nerve process fragments, detached during the dissociation, were surrounded by the normal plasma membrane.

This investigation was aimed at the morpho-functional evaluation of rat myocardium after isolated or combined effect of hypokinesia and 137Cs incorporation. Histological, morphometric, cytophotometric, radiometric and statistical methods were used. The histological characteristics of rat myocardium after exposure to both factors are presented, and the differences in the mechanisms of the compensatory response are shown. The incorporated radionuclides were found to cause early cellular death, which became attenuated with the extension of exposure period. The remaining cardiomyocytes underwent structural changes and hypertrophy, while the total heart mass remained unchanged. The combined action of radionuclides and hypokinesia resulted in the aggravation of the negative effects of both factors causing more profound destructive changes in the myocardium.

The histological material from 83 thyroid glands obtained from male and female human subjects during the medico-legal examination, was studied at the light microscopic level using the general and histochemical staining methods. The phenomenon of age-related increase of follicular colloid density was investigated and various forms of this effect are classified. Possible physicochemical factors of colloid modification are examined. The latter include: colloid "aging", follicular cell desquamation followed by cell death, thyroglobulin desialization, and accumulation of excessive amounts of DNA and RNA in colloid. Biological significance of the excessive colloid accumulation in the follicles with its subsequent increase in density is regarded in the neutralization and isolation of iodine and tyrosine, which are considered as xenobiotics.

Using the material obtained from 96 human corpses (480 skeletal vertebra), the linear parameters of vertebra were studied. The research objective was to study morphometric characteristics of lumbar vertebra of an adult person taking into consideration the individual and sexual variability, and to estimate the feasibility of calculation of a vertebra body volume with reference to percutaneous vertebroplasty. The results of research have demonstrated the general patterns of modification of linear and volumetric parameters of LI-LV, vertebra; it was shown that the values of linear parameters for the male samples were bigger than those for the female samples. The length of an axis of operational action, the linear and angular sizes of pedicles of vertebral arch were independent on gender factor, but, as a rule, gradually changed from LI to LV,. On the basis of comparison of the calculated and measured volumes of lumbar vertebra bodies, it is concluded that the mathematical model proposed by us has sufficiently high accuracy.

This work analyzes the controversial problems of lymphology, which require the scientific substantiation. Authors express their opinion on the functional anatomy of the lymphatic system, based on their own research and the literature data. The issues of lymphatic drainage from the spleen, bones, muscles, ligaments and fascia are discussed. The data on the diameter of the lymphatic vessels and its variability are presented. The significant attention is given to the changes of the lymphatic system structures during dehydration and rehydration. The role of lymphatic capillaries in the inflammatory processes is emphasized. The contradictions in the description of lymphatic postcapillaries are noted.

This review provides an analysis of current data on the tissue and cell components of the vaginal portion of the uterine cervix (ectocervix - EC) in human female and on their interrelations under normal conditions and in the development of some pathological processes. Detailed histological and immunocytochemical characteristic is given to two types of the epithelium - stratified squamous and columnar; the regularities and mechanisms of their junction displacement during various age periods are described. The data on the relation between the proliferation activity and apoptosis intensity in EC epithelium at different developmental stages are discussed. The data are presented on connective tissue component (stroma), its vascular and nervous structures. Cellular elements of the immune system contained in EC are examined. The significance of hormones and other biologically active molecules in the control of EC tissue functions and in coordination of their interaction, is emphasized.