scholarly journals A HEMATOPOIETIC PERIFOLLICULAR ENVELOPE IN THE RAT SPLEEN

Blood ◽  
1948 ◽  
Vol 3 (8) ◽  
pp. 953-959 ◽  
Author(s):  
E. B. KRUMBHAAR

Abstract About the Malpighian follicles of several species of rodents, and especially prominent in rats, is a perifollicular envelope composed of hematopoietic cells that takes active part in hemolytopoietic changes. The identity of the mononuclear cell comprising the greater part of this tissue has not been positively determined; it is probably a young lymphocyte. It is possibly the homologue of the pale centers of the Malpighian follicles in man and other mammals, though it has been found in rabbit spleens which also have pale centers. It should be possible to determine this identity by the use of a greater variety of stains, and of test poisons, and, if possible, of dynamic methods such as tissue culture and moving pictures. The envelope is separated from the Malpighian follicle by a thin rind of collagenous connective tissue, but on its outer margin it merges gradually with the red pulp. It often contains a scattering of erythrocytes, normoblasts, polymorphonuclear neutrophils, and rarely eosinophils and pigment-bearing macrophages. Some of these cells were so greatly increased under the pathologic conditions first studied that colonization was suggested; they were later thought to have probably wandered in. The collar never contains megakaryocytes or sinuses or blood vessels of any noteworthy size.

1965 ◽  
Vol 13 (01) ◽  
pp. 035-046 ◽  
Author(s):  
R. L Henry

SummaryWhite blood cells can no longer be considered simple trapped inclusions within thrombi. Their numbers in thrombi relative to blood counts increase with time. They appear to come from the blood flowing past the thrombus. They appear to migrate by amoeboid movement into the thrombic mass. Polymorphonuclear neutrophils have been shown to be lytic to fibrin and other proteins and thus can contribute to thrombus dissolution. There is increasing evidence that neutrophils may impart important cytotrophic function to proliferating cells during thrombus organization. Eosinophils are known to carr profibrinolysin and will release this precursor at sites of fibrin deposition. Mononuclear leukocytes can transform into fibroblasts in tissue culture and I consider a thrombus an ideal tissue culture medium. All of these cells can contribute to thrombus dissolution simply by mechanical weakening of the mass by migration into it, releasing enzymes, and allowing blood flow to carry away pieces of the thrombus as emboli. I extend my perspective on thrombosis by considering these intravascular solids as cell tissue cultures rather than simple blood clots or platelet aggregates.


In Vivo ◽  
2021 ◽  
Vol 35 (1) ◽  
pp. 313-317
Author(s):  
SATOSHI YOKOSE ◽  
YUKA KATO ◽  
KATSUTOSHI MATSUMOTO ◽  
PERRY R. KLOKKEVOLD ◽  
HENRY H. TAKEI ◽  
...  

2020 ◽  
Vol 9 (3) ◽  
pp. 64-71
Author(s):  
N. N. Shevlyuk ◽  
L. V. Khalikova ◽  
A. A. Khalikov

The aim of the study was to establish morphofunctional and immunohistochemical characteristics of large omentum in women with ovarian cancer.Material and methods. The large omenta of 48 women with ovarian cancer (low-grade differentiated seropapillary adenocarcinoma of high-grade malignancy) of II stage (n=20) and III stage (n=28) were studied. Histological sections were stained with overview histological and immunohistochemical methods (to reveal ki67, P53, CD34, CD7, CD4, CD8, CD61 proteins expression). Results. In patients, the size of the large omentum was characterized by high individual variability; in the presence of metastasis, the size of the omentum was reduced. Intensive development of blood vessels in the organ was noted, but in the presence of metastases stasis of blood corpuscles, leucocytic infiltration, and moderate edema of connective tissue were observed in the organ’s vessels. Areas of lymphoid tissue, both small lymphatic follicles and diffusely located lymphoid tissue, were revealed in the omentum. In most follicles, reactive centers were not marked, and the number of follicles was reduced in the presence of metastases in the omentum. The analysis of CD34+ cells distribution showed that they were identified both in the tumor and in the areas of the omentum adjacent to the tumor, which indicates a pronounced angiogenesis. An irregular distribution of CD7+ and CD8+ and CD4+ cells was revealed in the tumor tissues, as well as in the surroundings. Simultaneously with the expression of P53 protein, ki67 protein expression is revealed in the significant number of tumor cells (including endothelial cells of tumor blood vessels). The proportion of ki67+ cells in the tumor cell population was 60.1±3.3%. The presence of a large number of ki67+cells in the presence of P53 protein expression in them indicates the aggressiveness of the tumor, as well as a disturbance of apoptosis regulatory mechanisms in the cells. Ki67 expression was low in the omentum areas unaffected by metastases, and it was revealed in the certain areas of connective tissue in fibroblastic programmed differentiation cells. Conclusion. The results obtained indicate significant plasticity and reactivity of great omentum in the presence of tumor process in the body and confirm the important role of great omentum in protective reactions.


1941 ◽  
Vol 73 (1) ◽  
pp. 85-108 ◽  
Author(s):  
Philip D. McMaster

Minute amounts of Locke's or Tyrode's solution have been brought into contact with the interstitial connective tissue of the skin of the living mouse, at atmospheric pressure, in such a manner that the blood or lymphatic vessels are not entered directly. Under such circumstances these absorbable fluids enter the tissue spontaneously. Entrance is strikingly intermittent, not continuous, and so too when very slight pressures are brought to bear on the fluids (1). Hyperemia of the tissues, with accompanying dilatation of the blood vessels, increases the entrance of fluids at atmospheric pressure but it is still intermittent. By contrast, venous obstruction leads to intermittent backflow into the apparatus, but reflex hyperemia, following release of the obstruction, is attended by an increase of flow into the tissues in spite of the great reactive dilatation of vessels. The inflow is also intermittent. If the skin is deprived of circulation, fluid does not enter it at all at atmospheric pressure, though it moves in regularly and continuously if slight pressure is put upon it. Edema-forming fluids, described in the text, also enter in a continuous manner when forced into the skin of either living or dead animals. So too do serum and sperm oil. The findings indicate that the passage of interstitial fluid into the blood vessels may be intermittent under normal circumstances and its escape from them as well. The observed occurrence of intermittent flow in the blood vessels of several tissues (9, 15–25) will go far to account for the intermittent entrance of fluid into the skin.


1942 ◽  
Vol s2-83 (331) ◽  
pp. 299-316
Author(s):  
T. KERR

1. A general description is given of the pituitary of the perch (Perca fluviatilis L.), and histological details of its various parts. The subdivisions of the glandular component are confluent with each other but distinguished by their different cell types. The nervous lobe makes contact with all three of the subdivisions, but is separated from them by a layer of connective tissue, incomplete in particular areas. 2. The anterior glandular region (anterior lobe) has an anterior chromophil and a posterior chromophobe zone. The middle glandular region (transitional lobe) possesses brightly staining acidophils and basophils as well as chromophobes. The acidophils form a dorsal sheet, deeply indented by processes of the nervous lobe, the basophils lie ventrally and posteriorly, and chromophobes are common towards the extremities of the indentations. The posterior glandular region (intermediate lobe) is elaborately penetrated by nervous lobe processes; the cells are small and consist of amphiphils, dull basophils, and occasional dull acidophils. The possible homologies of these regions to the lobes of higher types are discussed. The nervous lobe is of loose glial tissue with many nuclei and blood vessels and some reticular and collagenous fibres. 3. Strongly acidophil spheres of various sizes and in various numbers occur in the middle glandular region. They originate in ‘sphere cells’ resembling eosinophil leucocytes and after enlarging become free in the tissues of the region. Later they appear to pass into the posterior processes of the nervous lobe to be the larger bodies of the Herring material. Finally these larger elements appear to break down to form a fine granulation, whose further fate could not be followed.


1985 ◽  
Vol 55 ◽  
Author(s):  
L.-H. Yahia ◽  
G. Drouin ◽  
C.-H. Rivard

ABSTRACTSpinal ligaments were obtained from normal and scoliotic individuals. Detailed morphological studies were carried out on the yellow, interspinous and supraspinous ligaments by light and scanning electron microscopy. Normal yellow ligaments are mostly constituted of dense elastin fibers with only a few collagen fibers and sparse blood vessels, while in normal interspinous and supraspinous ligaments, the presence of collagen is highly dominant. In the latter structures, the collagen fascicles are characterized by a regular waviness morphology. The fibrils constituting the fascicles appear either parallel or helical with respect to the fascicle axis. Structural changes are observed in the spinal ligaments of patients with congenital as well as idiopathic scoliosis. For yellow ligaments, only slight differences are found between normal and scoliotic specimens. However, alterations in collagen waviness and architecture are observed mainly in the supraspinous ligaments and to a lesser extent in the interspinous ligaments. In addition, increases in the cellularity, loose connective tissue and vessels are found in both forgoing ligaments. These results indicate that the more pronounced scoliosis-related changes occur in ligaments having the farthest distance from the axis of flexion-rotation.


Blood ◽  
1995 ◽  
Vol 85 (1) ◽  
pp. 96-105 ◽  
Author(s):  
PE Young ◽  
S Baumhueter ◽  
LA Lasky

The processes of angiogenesis and hematopoiesis require a high degree of coordination during embryogenesis. Whereas much is understood about the development of the vascular system in avian embryos, little information has been attained in mammals, predominantly because there are no specific markers for either blood vessels or hematopoietic cells in any developing mammalian system. We have recently shown that murine CD34 (mCD34) is expressed on the vascular endothelium in all organs and tissues of the adult mouse as well as on a small percentage of presumably hematopoietic stem cells in the bone marrow and fetal liver. Here we show that mCD34 is also expressed on the endothelium of blood vessels and on a subset of hematopoietic-like cells throughout murine development. mCD34 is first observed on the yolk sac endothelium of day 7.5 embryos and on a subset of hematopoietic cells within these yolk sacs. mCD34 expression is maintained on vessels and hematopoietic cells in all organs and tissues throughout embryogenesis. In addition, mCD34 is localized on growth conelike filopodial processes that appear at the budding edge of newly sprouted capillaries. Double staining of capillaries for mCD34 and laminin shows that these growth conelike processes seem to be free of laminin, whereas the formed capillaries seem to be coated with this extracellular matrix protein. Analysis of vessels in developing brain shows that these filopodial processes seem to be directed toward the ventricular epithelium, a previously described site of vascular endothelial growth factor synthesis. Finally, we show that the vascular structures of developing murine embryoid bodies also express mCD34. These data suggest that mCD34 is a useful marker for the analysis of the development of the blood vascular system in murine embryos.


Author(s):  
Raashid Luqmani

The vasculitides are a heterogeneous group of disorders that can range from mild inflammation of blood vessels in the skin, to organ- and life-threatening diseases. The term ‘vasculitis’ is a pathological description of blood vessel wall inflammation which leads to ischaemia and infarction of the target organs. Definitions and classifications of the primary vasculitides are mainly based on the predominant calibre of the blood vessels involved but incorporate clinical, pathological, and laboratory features. The secondary vasculitides usually occur in the context of other connective tissue diseases and are not discussed further in this section. Goodpasture’s disease is not usually included in the primary vasculitides, but has compatible clinical features of pulmonary capillaritis and glomerulonephritis.


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