双穗雀稗(Paspalum distichum)通透性生理和茎解剖结构补充研究

双穗雀稗根外皮层,茎角质层和茎节中的质外体屏障结构阻挡黄连素示踪液透过植物体。茎中机械组织包括周缘厚壁机械组织层,厚壁组织层和维管系统,髓部和皮层的蜂窝状厚角组织。茎中通气组织包括茎节间髓部和皮层的蜂窝状通气组织,茎节内的通气组织。双穗雀稗茎节间具有外侧、内侧和维管系统的质外体屏障,以及茎节周围质外体屏障的封闭结构。因此,该植物体完善的机械组织、通气组织、质外体屏障结构及其离子不通透性是其适应湿地环境的重要结构。     

Lymphoscintigraphic monitoring of the lower limb lymphatic system response to bone fracture and healing

Closed bone fractures, and torn muscles and tendons are "internal wounds". What kind of reaction do they evoke in the local and systemic immune system? Cellular debris of damaged tissue and extravasated blood cells are removed by scavenger cells. They are transported via lymphatics to the lymph nodes. There elimination of self antigens takes place. Clinically, no enlargement of lymph nodes is observed after closed fractures and soft tissue damage. The question arises whether there is really no enlargement of regional lymph nodes, in other words, no reaction to damaged cell antigens. This question was studied by using lymphoscintigraphy to visualize lymphatics and lymph nodes draining the site of closed bone fracture. The lymphoscintigraphic pictures of two groups of patients, those with a rapid noncomplicated healing of leg fractures, and those with protracted healing and undergoing surgical reconstructions, were evaluated. The surface area of lymphatic pathways and inguinal lymph nodes on the injured and contralateral normal limb were measured. Enlarged superficial lymphatics and inguinal lymph nodes were found in limbs with healed bone fractures, and decreased inguinal lymph nodes and visualization of deep lymphatics and popliteal nodes in the majority of patients with nonhealing fractures. There was a lack of correlation between age of patients, duration of healing, and surgical interventions and the lymphoscintigraphic changes. These findings suggest that the fracture gap tissue is a dominant source of signals to the lymph nodes, releasing cellular and humoral regulatory factors. Taken together, there is a strong immune reaction of lymph node to the fracture, although it cannot be recognized clinically.     

胃癌组织中PTEN、VEGF表达与肿瘤新生血管形成

目的探讨胃癌组织中PTEN、vascular endothelial growthfactor（VEGF）基因表达及其与肿瘤侵袭转移的关系。方法用RT-PCR和免疫组化方法检测胃癌、淋巴结转移组织中PTEN、VEGF mRNA和蛋白表达;用CD34检测肿瘤细胞微血管数。结果PTEN和VEGF mRNA表达阳性率在正常胃黏膜为76.5%与0.0%、胃癌组织为30.9%与69.1%、淋巴结转移组织23.6%与74.5%;PTEN和VEGF蛋白阳性率在正常胃黏膜为76.5%与0.0%、胃癌组织27.9%与82.4%、淋巴结转移组织16.3%与91.0%;胃癌组织中新生血管呈浸润生长,以淋巴结转移组织中明显。胃癌组织PTEN mRNA和蛋白低于正常胃黏膜（P〈0.01）,VEGF高于正常胃黏膜（P〈0.01）,PTEN与VEGF表达负相关（P〈0.05）,VEGF表达与新生血管形成正相关（P〈0.05）。结论PTEN基因失活和VEGF的过表达与新生血管形成相关,可能是通过调节包括VEGF在内的血管生成因子而在血管形成中起作用。     

Lymph node topography and various features of the metastasis of malignant kidney tumors

Due to investigations of 102 renal preparations performed on corpses of mature persons, topographic peculiarities of the lymph nodes, getting lymph from the left and right kidneys, are revealed. Every lymph node of the left kidney gets greater amount of lymphatic vessels than every node of the right kidney. The lymph, running from the right kidney, usually gets through a less number of the subsequently arranged nodes up to the thoracic duct, as compared to the lymph, that runs from the left kidney. A typical position for the node, which the renal lymphatic vessels get into, is the fatty tissue in the area of the angle formed by the aorta edge and the inferior wall of the corresponding renal artery. The lymphatic nodes of the right kidney are arranged in the fatty tissue more compact than the left ones. These peculiarities, revealed by morphological investigations, are proved by analysis of 114 case histories of persons suffering from malignant neoplasms in the kidneys.     

Lympho-granulocytic tissue associated with the wall of the spiral valve in the African lungfish Protopterus annectens

We describe the structure of the lympho-granulocytic tissue associated with the wall of the spiral valve of the African lungfish Protopterus annectens. The study was performed under freshwater conditions and after 6 months of aestivation. The lympho-granulocytic tissue consists of nodes surrounded by reticular tissue. The nodes are formed by an outer and an inner component separated by a thin collagenous layer. The outer component is a reticular-like tissue that contains two types of granulocytes, developing and mature plasma cells and melanomacrophage centres (MMCs). The inner component, the parenchyma, contains a meshwork of trabeculae and vascular sinusoids and shows dark and pale areas. The dark areas contain diffuse lymphoid tissue, with a large number of mitoses and plasma cell clusters. The pale areas contain a small number of macrophages and lymphocytes. Macrophages and sinus endothelial cells are filled with haemosiderin granules and appear to form part of the reticuloendothelial system of the lungfish. The reticular tissue houses granulocytes, plasma cells and MMCs and might serve for the housing and maturation of cells of the white series. After aestivation, the nodes undergo lymphocyte depletion, the suppression of mitosis, granulocyte invasion and the occurrence of cell death. By contrast, few histological changes occur in the reticular tissue. Whereas the nodes appear to be involved in lymphocyte proliferation and plasma cell maturation, the function of the reticular tissue remains obscure.     

Motheaten, an immunodeficient mutant of the mouse. I. Genetics and pathology.

A new recessive mutation, motheaten (me), is on chromosome 6, 21.9 +/- 4.3 recombination units distal to white (Miwh). Mice homozygous for the new mutation have neutrophilic lesions of the skin beginning as early as day 1, and pneumonitis with many macrophages in the alveoli as early as day 3. They suffer high mortality from birth onward and none has survived longer than 8 weeks. The lymph nodes may be enlarged, but the thymus, Reyer's patches, and lymphatic tissue of the spleen are much reduced in size. Lymph nodes, spleen, and Peyer's patches lack lymphatic nodules. The lymph nodes and spleen contain many plasma cells. There are increased numbers of neutrophils and monocytes in the peripheral blood, and increased numbers of neutrophils in bone marrow at the expense of red cell precursors. Hematopoietic tissue in the spleen is increased and appears more active than normal. Motheaten mice appear to have an immune deficiency beginning very shortly after birth.     

Development and ecological implications of dormant buds in the high-Paleolaltitude Triassic sphenophyte Spaciinodum (Equisetaceae)

Spaciinodum collinsonii, a Triassic sphenophyte from the central Transantarctic Mountains, Antarctica, is reinterpreted based on new material in order to clarify discrepancies from previous work and to detail the development and ecology of the Spaciinodum plant. Vegetative stems have alternating nodes and internodes, nodes distinguished by a solid diaphragm of tissue, internodes by the presence of vallecular (cortical) and carinal canals, and a hollow pith. Whorls of branches arise immediately above the nodes, alternating with the leaves of the subjacent nodes. Branches develop in the cortex and are anatomically similar to the stems. While Spaciinodum is similar to extant Equisetum, it is distinctive in that its large vallecular canals form a complete ring within the cortex and are separated only by thin fimbrils of tissue. The majority of specimens of Spaciinodum are now believed to be dormant buds with condensed nodes and internodes, with progressively longer internodal regions more basally. More apical portions of buds have cellular internodes because the areas where the canals will form have not yet ruptured from elongation. The abundance of buds and the absence of elongated stems in the permineralized peat deposit suggest that Spaciinodum underwent dormancy during the dark Antarctic winters.     

Individual and age variability of the anatomy and topography of the human lymph nodes

Analysis of the author's and literature data revealed two peculiarities in the lymph node anatomy. One of them is characterized with a great variability of amount and size of the nodes in every regional group. The second peculiarity is that age involution of the lymphoid tissue in the nodes is demonstrated in elderly and old persons as a decreasing amount of the lymph nodes and as their enlargement.     

Ex vivo imaging of T cells in murine lymph node slices with widefield and confocal microscopes

Naïve T cells continuously traffic to secondary lymphoid organs, including peripheral lymph nodes, to detect rare expressed antigens. The migration of T cells into lymph nodes is a complex process which involves both cellular and chemical factors including chemokines. Recently, the use of two-photon microscopy has permitted to track T cells in intact lymph nodes and to derive some quantitative information on their behavior and their interactions with other cells. While there are obvious advantages to an in vivo system, this approach requires a complex and expensive instrumentation and provides limited access to the tissue. To analyze the behavior of T cells within murine lymph nodes, we have developed a slice assay ¹, originally set up by neurobiologists and transposed recently to murine thymus ². In this technique, fluorescently labeled T cells are plated on top of an acutely prepared lymph node slice. In this video-article, the localization and migration of T cells into the tissue are analyzed in real-time with a widefield and a confocal microscope. The technique which complements in vivo two-photon microscopy offers an effective approach to image T cells in their natural environment and to elucidate mechanisms underlying T cell migration.     

Paravascular connective tissue structures of the veins of the pelvic cavity in man

The data on structure of the paravasal connective tissue formations in some parietal pelvic veins, in the utero-vaginal plexus veins, in the fatty tissue space veins of the rectum, of the vesicular and prostatic plexuses are presented, as well as those on connections between the fascial vaginae for the veins in the human subabdominal part of the pelvis and its fascial nodes. Theoretical interpretation of gaping of the pelvic fundal venous vessels is presented. Participation of the paravasal connective tissue formations in organization of the fascial nodes of the human small pelvis is stated.     

Selective chemotaxis of subsets of B lymphocytes from gut-associated lymphoid tissue and its implications for the recruitment of mucosal plasma cells

As they differentiate, precursor cells from the gut-associated lymphoid tissue are known to travel via the lymphatic system to the blood and then preferentially to home to various mucosal and exocrine sites such as the lamina propria of the gut and the lactating mammary gland, where they give rise to IgA-secreting plasma cells. The present study, directed at the mechanism by which the circulating precursors of mucosal IgA plasma cells selectively lodge in characteristic locations, explored the hypothesis that such homing is due to a locally produced chemotactic factor and that milk might be a source of such a factor. Subsets of lymphocytes bearing particular surface markers and purified by panning from lymph nodes of mice were examined in a micropore chemotaxis assay to search for the presence of chemotactic activity in mouse milk. The globulin fraction of whey was shown to contain a nondialyzable factor that is chemotactic for IgA (and also IgG)-positive lymphocytes when these are obtained from mesenteric lymph nodes as a source of mucosal-associated lymphoid tissue. Lymphocytes from peripheral lymph nodes, nonmucosal associated, were unaffected as were surface IgM-positive lymphocytes and T lymphocytes obtained from mesenteric nodes. Chemotactic activity for IgA lymphocytes was undetectable in mouse serum. The data are consistent with the idea that precursors of mucosal IgA plasma cells home to mucosal and exocrine sites in response to a specific chemotactic factor elaborated by local differentiated epithelial cells.     

Migration patterns of dendritic cells in the rat: comparison of the effects of gamma and UV-B irradiation on the migration of dendritic cells and Lymphocytes

To further define the underlying mechanisms of immune suppression induced by UV-B irradiation, we have examined the kinetics of homing patterns of in vitro UV-B-irradiated and gamma-irradiated-thoracic duct lymphocytes (TDL) compared to dendritic cells (DC). Our findings show that 111In-oxine-labeled TDL specifically home to the spleen, liver, lymph nodes, and bone marrow with subsequent recirculation of a large number of cells from the spleen to lymph nodes. In contrast, DC preferentially migrate to the spleen and liver with a relatively insignificant distribution to lymph nodes and an absence of subsequent recirculation. Splenectomy prior to cell injection significantly diverts the spleen-seeking DC to the liver but not to the lymph nodes, while the homing of TDL to lymph nodes is significantly increased. In vitro exposure of 111In-oxine labeled TDL to gamma irradiation does not significantly impair immediate homing to lymphoid tissues but inhibits cell recirculation between 3 and 24 hr. In contrast, gamma irradiation does not affect the tissue distribution of labeled DC, suggesting that DC are more radioresistant to gamma irradiation than TDL. Unlike the findings in animals injected with gamma-irradiated cells, UV-B irradiation virtually abolished the homing of TDL to lymph nodes and significantly reduced the homing of the spleen-seeking DC to the splenic compartment while a large number of cells were sequestered in the liver. The results of in vitro cell binding assay show that TDL, unlike DC, have the capacity to bind to high endothelial venules (HEV) within lymph node frozen sections while gamma and UV-B irradiation significantly inhibit the binding of TDL to lymph node HEV. These findings suggest that: (i) DC, unlike TDL, are unable to recirculate from blood to lymph nodes through HEV; (ii) although gamma irradiation impairs TDL recirculation, it does not affect DC tissue distribution; and (iii) UV-B irradiation impairs both TDL and DC migration patterns. We conclude that the lack of capacity of irradiated TDL to home to lymph nodes is due to damage to cell surface homing receptors and that the failure of DC to home to the lymph node microenvironment is related to the absence of HEV homing receptors on their cell surface.     

Adipose tissue,the immune system and exercise fatigue: how activated lymphocytes compete for lipids

Adipose depots that contain lymph nodes, and probably intermuscular fat in skeletal and cardiac muscle, are specialized to provision adjacent tissue in a paracrine mode. Perinodal adipocytes respond selectively to various cytokines and incorporate proportionately more polyunsaturated fatty acids. Lipolysis in the adipocytes of node-containing depots can be stimulated via inflammation of the enclosed lymph nodes. Repeated immune stimulation elicits properties characteristic of perinodal adipocytes in those elsewhere in the same depot, and hours later in other node-containing depots, but not in nodeless depots. Such site-specific properties of adipose tissue enable partitioning of dietary and metabolic supplies of fatty acids between competing tissues. Local interactions emancipate the peripheral immune system from competing with other tissues for lipids during immune responses, and may be especially important during periods of high demand, such as strenuous exercise. Biopsies of subcutaneous adipose tissue from sites remote from lymph nodes do not adequately represent the composition of fatty acids available to the immune system in situ, and perhaps that supplied to other tissues. Intermuscular fat in skeletal and cardiac muscle may also indicate paracrine relationships between adipocytes and "end-user" tissues. The concept of paracrine interactions between certain adipocytes and "user" tissue may account for the widespread contiguity between these tissues in vivo.     

Pan and sentinel lymph node visualization using a near-infrared fluorescent probe

A number of different types of agents have been employed to aid in the visualization of lymph nodes, particularly the sentinel lymph node, and to decrease the tissue destruction associated with the diagnosis of nodal metastases. The current study was performed to see if a novel macromolecular near-infrared fluorescent (NIRF) probe could be used to visualize lymph nodes after intravenous administration (pan-node visualization) or subcutaneous administration (sentinel node visualization), and serve as method for guiding dissection with interventional radiologic and surgical procedures. Cy5.5-PGC, the near-infrared dye Cy5.5 coupled to a protected graft copolymer (PGC), was injected (i.v. or s.c.) into nude mice. Twenty-four hours later white light and NIRF images were obtained on (i) the live animal, (ii) a partially dissected animal, and (iii) tissue specimens. With Cy5.5-PGC administered intravenously, axillary nodes were visualized from outside a living mouse. With partial dissection, iliac and aortic nodes were visible as concentrated foci of high-intensity NIRF signals. With subcutaneous injection in the front extremity, axillary and brachial nodes draining the injection site were easily visualized. NIRF imaging provides a nonradioactive method of visualizing lymph nodes through layers of tissue that can be employed with intravenous or subcutaneous injection.     

Microanatomical organization and cytoarchitectonics of lymphoid tissue in the mesenteric lymph nodes under conditions of experimental total hyperthermia

Microanatomical organization and cell composition of the rat mesenteric lymph nodes have been studied under conditions of experimental total hyperthermia. Possibilities of the compensatory-adaptive reactions of the lymphoid tissue have been determined. Disturbances of microhemo-++- and lymphocirculation in the lymph nodes in different time after hyperthermia are accompanied with accumulation of mast cells and eosinophils in various zones of the node; they normalize certain physiological parameters of microcirculation and permeability of the metabolic microvessel walls. In 30 days after a single total overheating of the rat organism, the microanatomical organization changes in the lymph nodes investigated are manifested as atrophy of B-dependent zones and further volumetric increase of the paracortical zone. Therefore, it is possible to think about a decreasing intensity of the humoral immunity and increasing intensity of the cellular one.     

Demonstration of the heterogeneity of the mast cell population on the basis of the mucopolysaccharide content.

From the aspect of its mucopolysaccharide content the mast cell population is not homogeneous. The pulmonary and heart muscle mast cells of the rat are alcian blue positive, the mast cells of the thyroid gland, lymph nodes, subcutaneous connective tissue, mesentery and peripheral nerve are safranin positive, whereas among the mast cells of the peritoneal cavity and the thymus there are both alcian blue and saffranin positive forms. The least acid mucopolysaccharides are in the mast cells of the peritoneal fluid, the mesentery and the lungs, whereas the most acid ones are in the mast cells of the lymph nodes, the subcutaneous connective tissue and the thyroid gland. There is a considerable difference between the two last mentioned organs. The mast cells of the subcutaneous connective tissue are end-product cells without amine or precursor turnover, whereas the mast cells of the thyroid gland incorporate and deliver amines, which may participate in the regulation of the host gland.     

Morphofunctional reorganization of the kidneys in lymphatic outflow disturbance

In 115 Wistar male rats structures and rates of tissue blood flow have been studied in the cortical and medullary renal substance histologically, polarographically (estimation of the volumetric tissue blood flow by hydrogen clearance). Systemic arterial (peritoneal aorta), venous (caudal vena cava) and lymphatic (renal lymph nodes) pressures have been measured, normal and after ligation of the thoracic duct at early (1-3 days), middle (1 month) and late (2-3 months) periods. In 1-3 days edema and dystrophy of the renal parenchyma, decrease of the blood flow rate in the cortical and its increase in the renal medullary substance, as well as a sharp elevation of pressure in the lymph nodes are observed. In 1 month of the experiment together with dystrophy and edema moderate sclerosis, decreasing blood flow rate in the cortical and medullary substance are noted. Increase of the systemic arterial and venous pressure and decreasing pressure in the lymph nodes, as well as a sharp increase of the renal nodes mass are revealed. In 2-3 months of the experiment, together with sclerosis of the renal parenchyma, elevated blood flow rate is observed in the kidneys and decreasing pressure in the lymph nodes up to its initial value takes place.     

Generation of Lymph Node-fat Pad Chimeras for the Study of Lymph Node Stromal Cell Origin

The stroma is a key component of the lymph node structure and function. However, little is known about its origin, exact cellular composition and the mechanisms governing its formation. Lymph nodes are always encapsulated in adipose tissue and we recently demonstrated the importance of this relation for the formation of lymph node stroma. Adipocyte precursor cells migrate into the lymph node during its development and upon engagement of the Lymphotoxin-b receptor switch off adipogenesis and differentiate into lymphoid stromal cells (Bénézech et al.¹⁴). Based on the lymphoid stroma potential of adipose tissue, we present a method using a lymph node/fat pad chimera that allows the lineage tracing of lymph node stromal cell precursors. We show how to isolate newborn lymph nodes and EYFP⁺ embryonic adipose tissue and make a LN/ EYFP⁺ fat pad chimera. After transfer under the kidney capsule of a host mouse, the lymph node incorporates local adipose tissue precursor cells and finishes its formation. Progeny analysis of EYFP⁺ fat pad cells in the resulting lymph nodes can be performed by flow-cytometric analysis of enzymatically digested lymph nodes or by immunofluorescence analysis of lymph nodes cryosections. By using fat pads from different knockout mouse models, this method will provide an efficient way of analyzing the origin of the different lymph node stromal cell populations.     

Raman spectroscopy can differentiate malignant tumors from normal breast tissue and detect early neoplastic changes in a mouse model

Raman spectroscopy shows potential in differentiating tumors from normal tissue. We used Raman spectroscopy with near-infrared light excitation to study normal breast tissue and tumors from 11 mice injected with a cancer cell line. Spectra were collected from 17 tumors, 18 samples of adjacent breast tissue and lymph nodes, and 17 tissue samples from the contralateral breast and its adjacent lymph nodes. Discriminant function analysis was used for classification with principal component analysis scores as input data. Tissues were examined by light microscopy following formalin fixation and hematoxylin and eosin staining. Discriminant function analysis and histology agreed on the diagnosis of all contralateral normal, tumor, and mastitis samples, except one tumor which was found to be more similar to normal tissue. Normal tissue adjacent to each tumor was examined as a separate data group called tumor bed. Scattered morphologically suspicious atypical cells not definite for tumor were present in the tumor bed samples. Classification of tumor bed tissue showed that some tumor bed tissues are diagnostically different from normal, tumor, and mastitis tissue. This may reflect malignant molecular alterations prior to morphologic changes, as expected in preneoplastic processes. Raman spectroscopy not only distinguishes tumor from normal breast tissue, but also detects early neoplastic changes prior to definite morphologic alteration.     

Lymphocyte migration in syngeneic lymph node implants

Lymph nodes implanted subcutaneously to syngeneic recipients were shown to regenerate after mass cell destruction. Regenerated lymphoid tissue has a resemblance to the cortical zone of intact lymph nodes. Microenvironment of regenerated lymphoid tissue provides homing of lymphocytes. However, migration of 51Cr-labelled lymphocytes to implants declined drastically, as compared to lymphocyte migration to intact lymph nodes. Attenuation of proliferative activity and the data of morphological analysis indicate a more prolonged retention of lymphocytes in implanted lymph nodes. The results obtained could be attributable to only partial recovery of sinus and vessel systems regulating the inflow and outflow of lymphocytes in lymph nodes.