Cellular mechanisms of compensatory processes of the kidney in relation to the mass resected

As a result of comparative investigation of compensatory processes in the kidneys at various degree of their resection, the most general regularities in these processes have been revealed: an initial functional strain of renal cells and their ultrastructures, the secondary increase in hypertrophy and hyperplasia of the renal cells and their organelles. The degree of manifestation of these regular reactions directly depends on the mass of the resected part of the kidney. Subtotal resection of the kidney (80%) is an operation that gets out of the limits of the organ's compensatory possibilities. A sharp decrease, up to complete disappearance of its cellular division in 2-3 weeks after the operation is of great importance. Mechanism for development of renal insufficiency is evidently connected with absence of cellular renewal against the background of their hyperfunction and their quick worn out, that is, evidently, resulted in deficiency of renal epithelium and functional defectiveness connected with it in the remained renal mass.     

The anatomicohistological characteristics of the formation of the mucosa of the human small intestine in the prenatal period of ontogeny]

The time, when the first villi appear, is defined. Quantitative composition, percent content, height of the villi of the mucous membrane in all parts of the small intestine during various periods of the intrauterine development are presented. In 17-week-old embryos at the level of the duodenum the first villi are noted and their formation in the middle part of the intestinal tube is revealed. By the 8th-9th weeks of development they appear at the level of the caudal part of the intestine. This demonstrates asynchronism of their formation in the cranio-caudal direction. The periods of their intensive growth in height in the first part of the intestine correspond to 8-10, 12-16, 24 weeks of the fetus age, in the second part--to 8-10, 18-20 weeks, in the third--to 10-12, 16-18, 26-28 weeks. These periods alternate with an abatement in growth intensity, which is connected with an increasing width of the villi themselves, with amount of newly formed villi and with changes of the intestinal tube diameter. The form of the villi is rather variable.     

Differentiation of the palatine tonsillar tissues of the human fetus]

Differentiation of epithelial and lymphoid tissues of the palatine tonsils was studied in human embryos at the age of 8-34 weeks of development by means of histochemical, immunomorphological and morphometric methods. The anlage of the palatine tonsils appears at the age of 9 weeks of fetal development. At the age of 13-14 weeks of fetal development the tonsil suspension contains 2 subpopulations of lymphocytes possessing properties of T-cells differing in the ability of their superficial receptors to interact with sheep erythrocyte antigens forming rosettes (RFC--rosette forming cells) and with antigens of their own erithrocytes (autoRFC). The number both increases sharply by the 16th week of gestation. Simultaneously, essential alterations are noted in epithelial and lymphoid tissues. In epithelium of crypts cornified cells appear; the amount of lymphoid tissue increases sharply, primary follicles without reactive centers appear, lymphocytic infiltration of epithelium occurs. The amount of RFC does not change considerably, and the amount of autoRFC has a tendency towards some increase. From the data obtained, it is possible to suggest that human palatine tonsils already at embryonic period participate in functioning of immunogenic organs and in maintaining of immunologic homeostasis of the fetal organism.     

Morphological criteria of early embryonal histogenesis exemplified by the development of the auxiliary ocular apparatus in humans]

In 50 human embryos at the age of 21 days--12 weeks of development, including the stages X-XXIII and beginning of the fetal period according to Carnegie's classification, spatial-temporal regularities on rearrangement of cellular material in the mesenchymal derivatives of the ocular auxiliary apparatus have been investigated. The main attention has been paid to ascertain the moments, when the first signs of differences appear in the previously homogenous cellular material of the differentiating mesenchyme around the ocular cup and in the eyelids, taking into account appearance of derivates in the ocular auxiliary apparatus: sclera, oculomotor muscles, stroma of the lacrimal gland, cartilagenous laminae in the eyelids and in the orbicular muscle. Regularities of cytochemical differentiation of the mesenchyme and its derivatives have been studied, taking into account the organ's changing topography. Morphometrical investigations of cells in the anlages mentioned are expanded and correlated with the time of their cytochemical differentiation. Correlation of the morphometrical and cytochemical data with the histological investigations has been performed.     

Comparative evaluation of age-related and organic characteristics of the structure of the adventitial nerve plexuses in human arteries

It has been stated by means of morphometric investigation of transversal sections of the nervous-vascular complexes of the thyroid, splenic and brachial arteries, stained after Weighert-Pahl, that in the human being during the first mature period the amount of nerves in adventitia of nervous arteries is 1.4-2.7 times greater than in the newborn, and in the old man--1.3-1.6 times less than in the mature person. Average total area of the nervous transversal sections changes in the same proportion with age. The age factor is the leading cause in increasing amount of nerves and the total area of their sections at the stage of productive development of the plexuses, as well as in decreasing of these indices in ageing process. In each age group the amount of nerves is proportional to the diameter of the artery lumen and to the organ's mass (spleen). The greatest amount of nerves at all stages of human development occurs in the adventitial plexuses of the thyroid arteries; they are less numerous in the plexus of the splenic artery, and their minimal amount is noted in the plexus of the brachial artery. Most of the nerves in adventitia of the arteries have microscopical diameter (less than 70 mcm), serve for selective, discrete innervation of the arterial wall.     

Disorders of vaginal development in the progeny of white rats exposed to x-ray irradiation

One hundred and twenty white rat embryos 13-22-day-old have been irradiated with x-rays (the dose 250 R) on the 12th-14th day of embryogenesis. The embryos have been divided into series of sagittal, frontal, transversal sections and stained by means of general histological methods. The irradiation performed on the days mentioned does not affect formation of the paramesonephric ducts. In all the experimental animals the caudal end of the paramesonephric duct is separated from the mesonephric duct as a solid cellular cord in which the lumen appears later. In the experimental females the disturbances developed after irradiation are manifested first of all in retardation of the main stages of the organ's formation; the retardation is observed: in fusion of the paramesonephric ducts, in resorption of the medial septum between the fused ducts, in separating the sinuous part of the vagina from the urogenital sinus, in recanalization of the vaginal epithelial cord. More severe lesions are presented as agenesia of the vaginal sinuous part and as its atresia represented by a transversal septum of the organ. The disorders in the vagina development are depended on massive primary necrobiotic radial lesions of the mesenchymal cells around the epithelial anlages of the small pelvis.     

Local characteristics and interrelations between glands and lymphoid conglomerations in the esophageal wall

Proper glands in 248 total preparations and lymphoid accumulations in 112 preparations have been investigated macro-microscopically in the human oesophageal preparations at various age. The organs have been obtained from 152 corpses of persons died from the death by violence and having no pathological changes in the organs of digestive and immune systems. The lymphoid tissue in the oesophageal wall is presented as accumulations of cells (prenodules++) and as diffusely scattered immune-competent cells. The glands and lymphoid accumulations are oriented as longitudinal rows. The lymphoid tissue accumulations are situated near to the glandular ducts, because the latter can serve as pathways for penetrating antigenic material into the organ's wall. The amount of the glands is maximal mature and elderly age, and that of lymphoid accumulations--at the second childhood. The dimensions of the gland body increase in the cranio-caudal direction, while the lymphoid accumulations, just the reverse, have their maximal dimensions in the upper third of the oesophagus. The gland bodies in places of the organ's anatomical narrowings in the section have more alveoles and are situated nearer to the covering epithelium than the glands in the neighbouring areas of the wall.     

Method of determining the quality of irrigation of the vessels of parenchymatous organs before injection]

The method suggested for qualitative estimation of the renal and hepatic vessels perfusion before an injection is based on measuring oscillations of the light beam diffused by the organ's surface (the source--a gas laser of continuous action of red spectrum). An absolute photometer protected by a red filter from external effects of light is used as a registrator. Successive injection of the renal and hepatic vessels with different masses and their investigation by means of roentgenography, preparation, carrosion demonstrate a satisfactory effectiveness of the method presented.     

Development of the neural apparatus of the human pancreas in prenatal ontogeny

In human embryos, prefetuses and fetuses from 6 to 40 weeks of development 82 preparations of the pancreas have been studied; 39 series of slices of the human embryos have been impregnated after Bielschowsky-Boeke. For the first time the nerves grow into the pancreas anlage in embryos of 16 mm long (6 weeks). The main sources supplying the pancreas with the nerves in the period studied are nervus vagus, celiac, hepatic, splenic, right adrenal, superior mesenteric and intermesenteric plexuses. Three stages in formation of the innervational apparatus of the pancreas are distinguished during the intrauterine development. The first stage is characterized by beginning of the nerve growing into the pancreas anlage. For the second stage an increased development of the intraorganic innervational apparatus and appearance of the all main sources of the organ's innervation are specific. The third stage is characterized with an increased differentiation of receptor zones in various parts of the pancreas. The development of the pancreatic innervational apparatus by the time of birth is not completed.     

Influenza epidemics in the USSR and Czechoslovakia in 1979-1984

In this work materials characterizing the appearance and development of influenza epidemic at the territories of the USSR and the Czech Socialist Republic are presented, the common features and differences of the epidemic process in both countries are recorded. The work shows that in both countries the appearance of this epidemic is caused by the same virus. In most cases the epidemic started earlier and lasted longer in the USSR, but morbidity rate during the epidemic was, on the whole, higher in the Czech Socialist Republic. Similarity in the course of the primary period of the epidemic processes from their appearance to their maximum rise was observed. In both countries the maximum rise of morbidity rate was registered on weeks 3-4 from the beginning of the epidemic.     

Development of germ cells in the ovaries of human fetuses in the early periods]

Histological methods were used for studying 30 ovaries of early human embryos from 7 to 11 weeks of development. It was shown that in the process of development of the ovary the number of mitotically dividing oogonia decreased from 76% in 7-8 weeks to 41% in the period of 10-11 weeks. The mototic division of oogonia was characterized by high activity from 3,6% to 6,8%. However, as early as in the ovaries of 7-8 week embryos there occurred transition of a part of oogonia into oocytes of preleptotene stages which were characterized by processes of spiralization and despiralization of chromatin in the nuclei. The amount of such oocytes increases in the process of development of the embryo. The amount of oocytes at the stage of condensation of chromatin "prochromosomes" increases from 7,6% to 14,4%, the amount of oocytes at the stage of the following despiralization increased from 2,1% to 21% when comparing the ovaries of embryos of 7-8 and 10=11 weeks of development. The size of nucleoli was found to change in the period of preleptotene transformations in the oocyte nuclei. Photographs of the stages in question are presented made from histological and total preparations.     

Potent histamine-releasing activity of atrahagin, a novel snake venom metalloproteinase

Poisonous snakebite wound is a popular disease worldwide. However, the pathogenesis remains unclear. In the present study, a novel metalloproteinase atrahagin in Chinese cobra (Naja atra) snake venom was purified, using heparin-sepharose followed by Superdex 75 gel filtration chromatography. Apart from its alpha-fibrinogenase activity, atrahagin potently activated human colon, lung and tonsil mast cells with the net histamine release being 25.9+/-4.4, 17.0+/-1.9, 13.2+/-3.6%, respectively. Time course studies revealed that the peak histamine release induced by atrahagin occurred at 12, 12 and 8 min following incubation of the enzyme with colon, lung and tonsil mast cells, respectively. The response of mast cells to atrahagin was abolished by preincubation of the cells with metabolic inhibitors or pertussis toxin, and by removal of Ca2+ and Mg2+ from the challenge buffer. In conclusion, activation of human mast cells by atrahagin indicated that the enzyme might contribute to the pathogenesis of snakebite wound.     

Water Status Changes During Development in Relation to the Germination and Desiccation Tolerance of Aesculus hippocastanum L. Seeds

Seed growth characteristics of Aesculus hippocastanum were examinedin detail during development from about 70 to 140 d after anthesis(DAA), mainly in 1988 and 1989. Mean fresh and dry weights increasedfor both the axis and the whole seed up to the time of peakseed fall at 135 DAA with no cessation before fruit abscission.Water per seed increased up to 100 DAA, after which no furtherincrease occurred; moisture content declined for the embryonicaxis and whole seed respectively from above 75 and 65% at 95DAA to 65 and 50% at 130 DAA. At fruit shedding in 1990 waterpotential values of -1·2, -2·6 and -1·1MPa were observed for the testa, cotyledon and axis tissuesrespectively; relevant sorption isotherms are presented. Decreases in seed moisture content during development were accompaniedby increases in desiccation tolerance and in germinability,both reaching their maximum at the time of peak seed fall. Atmaturity, only about 10% viability was retained on drying seedto 20% moisture content; it is confirmed that the seeds are'recalcitrant'. The exact relationship between moisture contentand germination during development was dependent on the deptof dormancy, as judged by the period of chilling required; eachduration of chilling at 2°C within the range 3-12 weeksyields a curve of sigmoid shape. No germination occurred at26°C without chilling, but nearly full germination can beobserved for samples collected at 6 weeks before maximum seedfall with 12 weeks chilling. The rate of moisture loss duringdesiccation at 15°C and 15% rh becomes reduced during development.The ontogeny of these 'recalcitrant' seeds is compared withthat of 'orthodox' seeded species and the implication of sigmoid-shapedcurves for the relationship between seed moisture content andgermination are considered.Copyright 1993, 1999 Academic Press Aesculus hippocastanum L., horse chestnut, seed development, water status, germination, desiccation intolerance, desiccation rate     

Histological studies on the development of porcine tonsils after birth

Tonsils form the topographically first immune barrier of an organism against the invasion of pathogens. We used histology to study the development of tonsils of pigs after birth. At birth, the tonsils consist of diffuse lymphoid tissue without any lymphoid follicle aggregations. At the age of 7 days, lymphoid follicles appeared in the soft palate tonsil. The lymphoid layer of the nasopharyngeal tonsil, soft palate tonsil, and lingual tonsil became thicker, and lymphoid follicles in the lamina propria were clearly visible at the age of 21 days. Secondary lymphoid follicles were present in the nasopharyngeal tonsil at the age of 50 days, and in the soft palate tonsil at the age of 120 days. Dendritic cells (DCs), CD3⁺ T cells and IgA⁺ B cells in the soft palate tonsil, nasopharyngeal tonsil and lingual tonsil increased continuously, especially during the first 21 days. The results suggested that tonsils have an important role in local immune defense against invading antigens after birth and will be beneficial for understanding the mechanisms of immunity in these animals after nasal and oral vaccination.     

Purification of human tonsil plasma cells: pre-enrichment step by immunomagnetic selection of CD31(+) cells

BACKGROUND: The advancement of knowledge about the biology of human normal plasma cells (PC) is hampered by their low frequency and difficult isolation. The aim of this study is to design a way of purifying these cells. METHODS: To this end, advantage was taken of the fact that human tonsil PC expressed surface CD31 at higher levels than the rest of tonsil B cells. RESULTS: The immunomagnetic selection of CD31(+) cells from tonsil B cells increased by a factor of 12 the proportion of PC, determined as CD38(high) cells. This method recovered half of the initial number of PC, and did not alter the PC functions, because IgG secretion was similar in control B cell cultures as well as in cultures of B cells obtained at successive steps of the selection procedure. In addition, CD38(high) cells pre-enriched by this technique were readily isolated by FACS sorting and clearly identified as PC. CONCLUSIONS: Therefore, immunomagnetic pre-enrichment of CD31(+) cells is an efficient method that allows the complete purification of human functional PC.     

The effect of long-term hyperbarism on pregnant guinea pigs and their progeny

The effect of hyperbarism has been investigated on 1-3-, 4-5- and 8-10-week pregnant rats and their offsprings. It was found that the mortality rate of pregnant rats is two times higher after hyperbaric exposures than in control animals. The animals exhibit the highest sensitivity at a stage of 8-10 weeks. Hyperbaric conditions significantly affect offsprings. Only 53% of newborn puppies were found to be normal, whereas 35% were born dead and 12% revealed various abnormalities. The highest sensitivity was observed during organogenesis (4-5 weeks), the mortality rate during this period reached 70%. The body mass in newborn puppies was significantly lower than in control animals. The most significant retardation in the development was observed in animals which were subjected to the effect of hyperbarism at the 4-5-th week of intrauterine life.     

Growth and Maintenance of an Embryogenic Cell Culture of Daylily (Hemerocallis) on Hormone-free Medium

Callus cultures of the diploid daylily (Hemerocallis) clone‘Autumn Blaze’ were initiated and maintained inhormone-containing nutrient medium. At various times (from 6weeks to 1 year) after being initiated, hormone-derived cultureswere evaluated for their ability to be maintained and to multiplyon hormone-free medium at low pH (between pH 4 and 4.5). Cultureshad to be exposed to hormone-containing medium for at least12 weeks before they could be maintained on hormone-free mediumat low pH. The transition to maintainability on low pH hormone-freemedium included the production of many aberrant embryonal forms('neomorphs'). However, all hormone-derived cultures testedconsisted entirely of preglobular stage proembryos (PGSPs) after12–24 weeks on low pH hormone-free medium. PGSP cultureshave been maintained and multiplied as such for over 1 yearon low pH hormone-free medium. PGSPs continue their developmentinto various somatic embryo stages when cultured on hormone-freemedium buffered at pH 5.8. The production of well-formed somaticembryos was greatly enhanced when PGSPs were plated on activatedcharcoal impregnated filter papers that were placed on top ofthe agar surface. The gross morphology and histology of thePGSPs and stages of somatic embryo development are presented.The work shows that the ability of hormone-free medium at lowpH to permit PGSP multiplication without development into laterstages of embryo development is not restricted to carrot. Hemerocallis cv, ‘Autumn Blaze’, daylily, somatic embryogenesis, hormone-free medium, tissue culture     

Morphologic and histochemical indices of hepatic function following bilateral subdiaphragmatic vagotomy

A complex morpho-functional investigation of the rat liver was performed after bilateral subdiaphragmal vagotomy by means of light, electron microscopy methods and a quantitative histochemical method. Some ultrastructural disorders in hepatocytes and in stellate reticuloendotheliocytes were revealed, with their maximal manifestation 7 days after vagotomy. At later stages (45 and 90 days), compensatory-restorative processes develop resulting in considerable (but not complete) normalization of the organ's structure. Quantitative histochemical investigations have demonstrated that even at the highest degree of the resulted disorders the liver preserves its ability to synthesize and accumulate glycogen, but the intensity of the process is considerably lowered. Functional changes are reversible in their character and correlate to the degree of structural disorders.     

Activation of human B lymphocytes. III. Concanavalin A-induced generation of suppressor cells of the plaque-forming cell response of normal human B lymphocytes.

Con A-induced suppression of the direct PFC response to polyclonal stimulation in human B cells has been described. Two types of experiments are presented. First, Con A was added directly to PWM-stimulated PB or tonsil cells resulting in a dose-dependent suppression of the PFC response, with maximal suppression occurring at a Con A concentration of 10 mug/ml. This suppression is completely removed by the simultaneous addition of alphaMM to the cultures. Secondly, Con A stimulation of tonsil or PB lymphocytes generated a population of cells which when added to autologous lymphocyte cultures induced a marked and reproducible suppression of the PFC response. The generation of suppressor cells is dependent on cell division and is blocked by alpha MM. Once generated the process of suppression is indpendent of the presence of Con A itself and is mediated by an activated lymphocyte population. These studies demonstrate a simple and reproducible model for the generation of a population of suppressor cells capable of inhibiting the direct PFC response to PWM-induced polyclonal activation of normal human B lymphocytes.