The reaction of somatic lymph nodes to experimental exposure to sulfide baths]

Influence of strong sulfide baths of the sanatorium "Talgi" to the popliteal and superficial inguinal lymph nodes (LN) has been studied in 35 rats (140-150 g of body mass) and 15 animals have been used as the control. The slices are stained with hematoxyli-eosin, after van Gieson, Romanovsky-Giemsa, Kurnik and silver nitrate impregnation after Foot. The section area of the LN decreases, but amount of lymphoid nodules increases (especially in deep layers of the cortex). In the germinative centers amount of middle lymphocytes and mitoses becomes larger. In the internodular zones of the popliteal nodes amount of macrophages and eosinophiles enlarges significantly, and in the inguinal-amount of mast cells and eosinophiles. In the medullary sinuses amount of macrophages declines. In the medullary cords amount of immature plasma cells and blasts increases, while amount of mature cells decreases.     

The anatomy and topography of the lymphoid formations of the human stomach in postnatal ontogeny]

By means of macro-microscopical methods 80 stomachs from persons of various age have been studied. In the mucous membrane of the human stomach during all age periods of postnatal development the lymphoid tissue is present as diffusely scattered lymphocytes, their microaccumulations and lymphoid noduli. Maximal amount of the lymphoid noduli is observed during the second mature age. The greatest number of the lymphoid noduli per 1 cm2 of the mucous membrane surface is revealed in the area of the lesser curvature and in the pyloric part of the stomach. Most often the lymphoid noduli are situated in the depth of the lumen proper of the mucous membrane, somewhat more seldom--in its more superficial parts, in the muscular lamina and in the submucous tela. The lymphoid noduli with germinative centers are met beginning from the first childhood up to old age. The greatest amount of diffusively scattered lymphocytes is situated near the lymphoid noduli and in the deep layer of the lamina proper of the mucous membrane.     

Changes in the iliac lymph node of the rat in aseptic uterine inflammation and during its correction]

In the lymphoid tissue of the iliac lymph node at an aseptic inflammation in the uterus the greatest changes have been revealed in 48 h from the moment, when the foreign body has been introduced. They are manifested at the tissue level (increasing content of macrophages, lymphoblasts, large lymphocytes, plasmoblasts, immature plasmocytes, mast cells, neutrophils), as well as at the organic level (increasing amount of secondary lymph noduli, increasing area of the paracortical zone, decreasing area of the cortical plateau, of the medullary intermediate sinus, medullary cords). Use of carbomineral sorbents ensures correction of the inflammation; this is demonstrated as reduction of reactive changes in the regional lymph node.     

Mesenteric lymph nodes in the rat after exposure to hydrocortisone

The construction and cell composition of the cortex and medulla have been morphometrically studied after 1-, 3-, 5-, 7- and 14-aliquot injection of medical doses of hydrocortisone (0.25 mg per 100 g of body mass). The body mass of the animals decreases, as does the size of the mesenteric lymph nodes. The lymphocyto- and immunocytopoietic functions intensify in the medullary cords with a simultaneous inhibition of these processes in the cortical plateau and in the lymphoid noduli. On the 5th and 7th days there is some increase in the section area of the cortex, while that of the medulla decreases. The part of small lymphocytes in these structures grows large. Therefore, it is possible to suppose a definite tendency towards restoration of the structural components within two weeks.     

Degree of chromatin activity and the RNA level in lymphocytes of popliteal lymph nodes of dogs after administration of an antigen]

In the experiment performed on 127 dogs by means of cytospectrofluorometric analysis, using fluorochrome acridine orange in dynamics up to 1 year, changes in the level of chromatin activation and RNA content have been studied in lymphocytes of the germinative centers and the crown of lymphoid nodules, in the paracortical zone and medullary cords of the regional and contralateral popliteal lymph nodes, after subcutaneous injection of antigen (BCG vaccine, 0.2 mg/kg) into the lateral area of the foot of the left pelvic extremity. The immune response is accompanied with a periodical increase in the level of chromatin activation and RNA content in populations of lymphocytes in the regional and contralateral popliteal lymph nodes with maximum in 6 h, 3-7 days, 1-3 months after the antigen injection. The intensity of these processes has an unequal level in lymphoid cells of various structural components; it is higher in lymphocytes of the contralateral lymph node.     

Structure of the small-intestinal lymphoid patches in albino rats at various stages of their development

The following stages in lymphoid patches (LP) development have been revealed: I-1-6, II-7-14, III-15-21, IV-22-30 days; during these periods lymphoid noduli with germinative centers, cupolae and internodular areas are formed. Amount of all kinds of cells in the LP parenchyma and their rearrangement in the zones takes place. In one-month-old rats blast forms predominate in the LP germinative centers, and small lymphocytes--in the zone of small lymphocytes of the noduli and internodular areas. Under conditions of antenatal effect of an antibiotic on the system mother--fetus there is no disturbances in formation of the anatomical structures. However at each stage of development the small intestine LP are not mature, concerning their cellular composition. Amount of cells decreases, their interrelationship changes. Lympho- and plasmocytopoiesis decreases.     

The immune system and age

Basing on numerous facts, obtained during last years at investigation of the immune system organs, a definite idea has been formed on peculiarities of their structure during certain stages of human ontogenesis. The immune organs appear early in embryogenesis and by birth they have reached their morphological maturation. This is evident as formation of diffuse lymphoid tissue in lymphoid noduli, that can have germinative centers, where young cells of the lymphoid line are formed. The immune system organs develop especially quickly after birth during first years of the postnatal ontogenesis. The peak in development of the organs of immunogenesis, amount and size of the lymphoid noduli occurs during the childhood and adolescent age. Each immune organ has its peculiarities that are determined by their place in the organism, value and intensity of antigenic effect. Beginning from the adolescence and youth amount of the lymphoid tissue and lymphoid noduli in the organs decreases, in their place connective and adipose tissue grows out.     

Morpho-functional status of the lymph nodes of rats during rehabilitation after exposure to vapors of dimethyl sulfate]

By means of histological methods inferior tracheobronchial lymph nodes have been investigated in 48 Wistar rats in 2 weeks and 3 months after cessation of inhalation of DNSV at maximum possible dose (0.1 mg/m3) for 2 and 14 days. Cell composition of the lymph nodes and cross sections of structural components have been compared. The cross section of the cortex decreases, while that of the medulla increases in comparison with corresponding parameters of the acute experiment. In 2 weeks and 3 months after DMSV effect for 2 days the part (%) of poorly differentiated cells and middle lymphocytes increases, while content of plasma cells in the medullary cords decreases. During rehabilitation after DMSV effect for 14 days a low level plateau is noted (as in the acute experiment). However, in lymphoid nodules++ within content of the poorly differentiated cells and middle lymphocytes in the cortical germinative centers in 2 weeks and 3 months the number of the poorly differentiated and reticular cells increases essentially, as well as mitotically dividing cells (in comparison to the acute experiment). In the medullary cords of the lymph nodes after 3 months of rehabilitation content of immature plasma cells is essentially higher than in 2 weeks of rehabilitation and than in the acute experiment. During rehabilitation the level of cells destruction in the lymph nodes noticeably decreases in comparison to the acute experiment.     

Microscopic anatomy of small-intestinal lymphoid patches in children and adults

Longitudinal histological sections of lymphoid patches (LP) in the small intestine, stained after van Gieson and with hematoxylin--eosin, obtained from 105 corpses of persons at the age of 0 up to 90 years have been studied. The LP parenchyma is presented as accumulation of lymphoid nodules++ with a germinative center, or without it and diffuse lymphoid tissue. The lymphoid nodules++ situate both in the mucous membrane and in the submucous tela of the small intestine. The area of the LP components in the newborns is the greatest--84% from the whole area of the LP section. During the human life it decreases and by the old age it makes 47%. The lymphoid nodules++ area with the germinative center in the newborns makes 21% from the area of the LP section, in children from 1 to 3 years of age it increases up to 50%, then it gradually decreases and in the elderly age it makes only 3.8%. The diffuse lymphoid tissue in the LP composition is revealed in all age periods. Size of the lymphoid nodules++ patches, situating in the jejunum and ileum walls in the newborns is the same. In children at the age of 10 days--12 years the LP nodules++ in the ileum are larger than those in the sejunum. The size of the LP noduli increase up to the period of the second childhood then decreases. The height of the lymphoid noduli in persons of mature, elderly and old ages decreases twice in comparison with the children of 3-12 years of age.     

Histological and enzyme histochemical investigation of the hemal nodes of the hair goat

Abstract

We investigated the structure of the hemal node in six healthy hair goats using histological and enzyme histochemical methods. After processing, tissue sections were stained with Crossman's trichrome, Gordon-Sweet's silver and Pappenheim's panoptic stains. Alpha-naphthyl acetate esterase (ANAE) and acid phosphatase (ACP-ase) were demonstrated in frozen sections. Hemal nodes were encapsulated by connective tissue and few smooth muscle cells. Several trabeculae originated from the capsule and extended into the hemal node. A subcapsular sinus was present beneath the capsule and was continuous with the deeper sinuses. Subcapsular and deep sinuses were filled with erythrocytes. The parenchyma consisted of lymphoid follicles, diffuse interfollicular lymphocytes and irregular wide lymphoid cords. Cortical and medullary regions were not distinct. ANAE (+) and ACP-ase (+) cells were located mainly in the germinal centers of the lymphoid follicles and also were scattered equally in the interfollicular region and lymphoid cords. Monocytes, macrophages and reticular cells displayed a diffuse positive reaction, whereas localized granular positivity was observed in lymphocytes. We demonstrated that the general structure of the hair goat hemal nodes is similar to that of other ruminant species.     

Cellular composition of structural components of the lymph nodes of rats during rehabilitation after dimethyl sulfate poisoning

By means of microanatomical methods the inferior tracheobronchial lymph nodes have been investigated in 48 Wistar rats in 2 weeks and 3 months after discontinuance of inhalation of dimethylsulfate (DMS) vapours for 2 and 14 days by the animals in concentration 2.0 mg/m3, that is to say during rehabilitation period. Comparison of relative parameters of the structural components areas and cell composition of the lymph nodes has been carried out. During rehabilitation period after DMS inhalation for 2 days the cortical and medullary areas in histological preparations do not essentially differ from corresponding parameters of an acute experiment (2 days, 2.0 mg/m3, without rehabilitation). Amount (%) of cells with mitotic figures in the lymphoid nodules++ increases in 2 weeks and in 3 months. Contents of poorly differentiated cells during rehabilitation periods increase in the cortical plateau, but keeps nearly at the same low level as during the acute experiment in the lymphoid nodules++. In 2 weeks after DMS influence for 14 days, the cortical and medullary area in the histological preparations reach the control levels. In the lymphoid nodules++ a relative amount of reticular, poorly differentiated, mitotically dividing cells increases, and in the medullary cords contents of middle and small lymphocytes become greater in comparison with the acute experiment (14 days, 2.0 mg/m3, without rehabilitation).(ABSTRACT TRUNCATED AT 250 WORDS)     

Histological and enzyme histochemical investigation of the hemal nodes of the hair goat

We investigated the structure of the hemal node in six healthy hair goats using histological and enzyme histochemical methods. After processing, tissue sections were stained with Crossman's trichrome, Gordon-Sweet's silver and Pappenheim's panoptic stains. Alpha-naphthyl acetate esterase (ANAE) and acid phosphatase (ACP-ase) were demonstrated in frozen sections. Hemal nodes were encapsulated by connective tissue and few smooth muscle cells. Several trabeculae originated from the capsule and extended into the hemal node. A subcapsular sinus was present beneath the capsule and was continuous with the deeper sinuses. Subcapsular and deep sinuses were filled with erythrocytes. The parenchyma consisted of lymphoid follicles, diffuse interfollicular lymphocytes and irregular wide lymphoid cords. Cortical and medullary regions were not distinct. ANAE (+) and ACP-ase (+) cells were located mainly in the germinal centers of the lymphoid follicles and also were scattered equally in the interfollicular region and lymphoid cords. Monocytes, macrophages and reticular cells displayed a diffuse positive reaction, whereas localized granular positivity was observed in lymphocytes. We demonstrated that the general structure of the hair goat hemal nodes is similar to that of other ruminant species.     

Histological changes of the mouse thymus during involution and regeneration following administration of hydrocortisone

Summary A histological study has been made of the thymus in mice during acute involution and regeneration following administration of hydrocortisone. The cortex undergoes remarkable changes in the microscopic structure during involution and regeneration. During involution the lymphocytes in the cortex rapidly decrease and are removed. Then a rapid replacement of lymphocytes occurs during regeneration. On the basis of formation and repopulation of lymphocytes the regenerative process of the cortex is divided into seven phases. The reconstitution of the cortex proceeds more rapidly in females than in males. Newly formed lymphocytes take origin from the mesenchymal cells in the cortex. Such mesenchymal cells become distinguishable from epithelial reticular cells during involution. They appear to engulf destroyed lymphocytes and debris during involution and then transform into immature lymphoid cells during early regeneration. The findings may support the recent reutilization concept that destroyed lymphocytes are phagocytized and reutilized by reticular cells in heteroplastic differentiation into immature lymphoid cells. In the cortex PAS-positive sudanophilic cells which are derived from the perivascular and subcapsular connective tissue appear with involutionary changes. They become gradually reduced again with progress of the regeneration of the cortex. During involution the medulla are temporarily filled with lymphocytes migrated from the cortex. The epithelial reticular cells in the medulla are found grouped in cords or clumps in the severely involuted thymus. In the medulla there are two types of PAS-positive epithelial reticular cells; one contains a large, colloid-like, PAS-positive inclusion within the cytoplasm and the other has cytoplasm diffusely filled with PAS-positive substance. During involution and early regeneration, the former type increases while the other shows almost no significant changes. Hassall's corpuscles somewhat increase in frequency during involution and early regeneration.     

Characteristics of the cellular reactions of the T- and B-dependent areas of the regional lymph nodes in dogs to the administration of immunodepressants

Mesenteric, bifurcational, axillary and popliteal lymph nodes have been studied in 22 healthy mature male dogs. Amount of blast cells, small lymphocytes, plasma cells and macrophages has been taken into account in the paracortical zone, in the germinative centers and in the medullary cords. For two weeks to one group of the animals every day imuran in turn with aurantin (10 mg/kg and 25 mg/kg) are injected, or antilymphocytic serum (ALS) intraperitoneally every other day (0.1 ml/kg). The combined injection of imuran and aurantin produces a more pronounced toxic effect to the hemopoietic organs than ALS. ALS is more specific for T-dependent zones of the lymph nodes. In the dose and interval mentioned ALS is an immunostimulating preparation for the immunocompetent cells of the germinative centers of the lymph nodes. The reaction of the lymph nodes depends on their regional belonging.     

Spatial-temporal organization of the deep cortex of the lymph node

In various areas of the deep cortex: central and peripheral parts, as well as T-territory (adjoining the fundus of the germinative center) various cells (small and middle lymphocytes, immunoblasts, plasmoblasts, immature and mature plasma cells and mitotically dividing cells) have been counted. The population density of various immunocompetent cells differs significantly in various areas of the deep cortex. Immunoblasts predominate in the center, cells of the plasmic line--in the periphery of the deep cortex and in the T-territory. Fluctuations of the population density are time-dependent. Spectral composition and parameters of rhythmicity for each cellular type and general course of the process are estimated. In the spectral composition ultradian components predominate. The circadian components are more specific for T- than for B-dependent zone. For immunoblasts in all the zones a common period of fluctuations, nearly 10 h, is revealed, and for the cells of the plasmic line 7 hours' period is common; therefore, it is possible to suppose presence of synchronizing pace-makers of the rhythm for T-lymphocytes, on the one hand, and for antibody-forming cells, on the other hand. Spectral composition of rhythmicity of the cells in the T-territory and in other part of the deep cortex has a number of similar components, that demonstrates functional unity of these zones. A higher part of the cells of the plasmic line in the T-territory and in the periphery of the deep cortex is, perhaps, connected with their migration along these areas towards medullar cords. The general process is of a complex character, rises and drops are registered at various time of the day.     

Structural changes in popliteal lymph nodes in the graft vs. host reaction to H-Y antigen in male C57BL/6-strain mice

Regional popliteal lymph nodes in intact, control and experimental (I, II, III groups, respectively) have been studied by means of the morphometric method in male C57Bl/6 line mice at the pick of the reaction produced by injection of spleen cells and mesenteric lymph nodes obtained from syngenic females and repeatedly immunized to H-Y antigen (10 animals in each group). Injection of the cell suspensions from the immunized and intact females of the C57Bl/6 mice result nearly in two-fold increasing mass of the regional popliteal node at the expense of enlarged size of all its zones. Changes in cytoarchitectonics of the node structural components result from redistribution of certain cellular elements. The essential changes in the cell composition of the lymph nodes in the II and III male groups are accompanied with an increasing part of the stromal reticular cells. Simultaneously, content of small lymphocytes decreases significantly. In the III group of mice there is a sharp increase in the content of young forms of the lymphoid line cells in all structural components of the node, as well as in eosinophilic granulocytes in medullary cords. In the dark cortical zone of the nodes (III group) there occur tissue basophils (mast cells), that, together with increasing number of acidophilic granulocytes and appearance of neutrophilic cells, demonstrates that there is an inflammatory reaction in the organ studied as a response to the lymphocytic suspension injected. In the experimental group of the animals a complete disappearance of plasma cells is noted in the node cortex, but some increase of their part takes place in the medullary cords.     

Topography,ultrastructure and phagocytic capacity of avian lymph nodes

Summary The structure of the avian lymph node (ALN) is characterized by a thin capsule, thin lymphoreticular cords, and an absence of trabeculae. It is not possible to subdivide the ALN into cortex, paracortex and medulla, or to subdivide the system of sinuses into marginal, trabecular and medullary divisions. The lymphoreticular cords contain avian germinal centers (AGC) with B-lymphocytes and the area of T-lymphocytes.Postcapillary venules are responsible for the recirculation of lymphocytes. Sinus reticular cells do not exist in the ALN, but free macrophages are present. The phagocytic capacity of the macrophages was determined by injection of vital dyes (India ink, Berlin blue) and inoculation with Candida cells. Macrophages filled with markers migrate from the lymph sinuses into the lymphoreticular cords and further into the AGC. The mobility of the macrophages is remarkably lower after phagocytosis of Candida cells.This study is dedicated to Prof. Dr. Dr. h.c. Hugo Grau (Weilheim) with sincere appreciation and respect     

Structure of the arterial bed in human lymph nodes

Blood vessels, that bring blood to various areas of the human superficial inguinal lymph nodes are predominantly arterioles and precapillaries. They are often arranged radially from the hilus to the capsule and from the capsule towards the portal thickening. The arteries and arterioles of the portal and capsular trabeculae reach the paracortical zone, occupying an intermediate position between the medullary cords and the cortex of the lymph node. The arterioles of the paracortical zone, passing between the cortex and the medullary cords, acquire an arcuate appearance. In both directions from them (into central and peripheral areas of the node) precapillaries branch off at a right angle. The cortex is supplied with blood by the arteriolar branches of the paracortical zone and the capsule of the node. The cortical precapillaries branch into capillaries either within the lymphoid nodules, or along their periphery. In the medullary cords those arterioles branch, that get from the portal thickening, portal trabeculae and paracortical zone.     

Late effect of carbon disulfide on the lymph nodes in rats]

Cell composition of the cortical plateau, medullary cords and lymphoid nodules++ has been determined in 180 Wistar rats in 2 weeks, 1 and 3 months after inhalation of carbon disulfate vapour for 2, 7 and 14 days in a maximum permissible concentration (1 mg/m3) and in the control group. In 2 weeks after cessation of the vapour inhalation activity of lymphocytopoiesis, blastopoiesis, cell differentiation decreases, macrophagal and plasmocytic reactions are weakly manifested. In 1 month certain signs of compensatory-adaptive reaction are noted; they are seen as increasing proliferative processes and activation of cell differentiation in the lymphoid nodules++ and a sharp plasmatization of the medullary cords. In 3 months after the experiment retardation of lymphocytopoiesis is still definitely manifested in the cortical plateau and medullary cords and essential destructive processes are observed against the background of local increase of the functional activity of the lymphoid nodules++.     

Blood vascular network of the rat lymph node: tridimensional studies by light and scanning electron microscopy

Many aspects of the blood vascular network of the lymph node are unknown, and others need confirmation. We have studied the blood vasculature of rat peripheral lymph nodes by means of carbon perfusion and vascular cast corrosion techniques. At the hilus of the node, an artery gives off arterioles running in medullary cords towards the cortex. Some reach the peripheral cortex directly, branching there into slender cortical vessels. Other arterioles enter the periphery of the deep cortex units, and then head towards the peripheral cortex. Upon reaching it, they curve part way above the center of the deep cortex units and provide slender branches to the overlying peripheral cortex. Dense plexuses of capillaries arise from arterioles in the medullary cords, in the periphery of the deep cortex units, and in the outermost stratum of the extrafollicular zone of the peripheral cortex. In the cortex, the draining high endothelial venules are restricted to the extrafollicular zone and to the periphery of the deep cortex units. At the cortico-medullary junction, these peculiar venules transform into regular medullary venules which form the hilar veins. In contrast, the folliculo-nodules and center of the deep cortex units are little vascularized by a loose capillary network, while no vessels occur in the subsinus layer. These features of the node vascular network are of interest in relation to the node architecture.