Ultrastructure of Lymphatic Capillaries in the Transport of Colloidal Particles

Author(s):  
L. V. Leak ◽  
J. F. Burke

The vital role played by the lymphatic capillaries in the transfer of tissue fluids and particulate materials from the connective tissue area can be demonstrated by the rapid removal of injected vital dyes into the tissue areas. In order to ascertain the mechanisms involved in the transfer of substances from the connective tissue area at the ultrastructural level, we have injected colloidal particles of varying sizes which range from 80 A up to 900-mμ. These colloidal particles (colloidal ferritin 80-100A, thorium dioxide 100-200 A, biological carbon 200-300 and latex spheres 900-mμ) are injected directly into the interstitial spaces of the connective tissue with glass micro-needles mounted in a modified Chambers micromanipulator. The progress of the particles from the interstitial space into the lymphatic capillary lumen is followed by observing tissues from animals (skin of the guinea pig ear) that were injected at various time intervals ranging from 5 minutes up to 6 months.

1968 ◽  
Vol 36 (1) ◽  
pp. 129-149 ◽  
Author(s):  
L. V. Leak ◽  
J. F. Burke

The fine structure of the lymphatic capillary and the surrounding tissue areas was investigated. Instead of a continuous basal lamina (basement membrane) surrounding the capillary wall, these observations revealed the occurrence of numerous fine filaments that insert on the outer leaflet of the trilaminar unit membrane of the lymphatic endothelium. These filaments appear as individual units, or they are aggregated into bundles that are disposed parallel to the long axis of the lymphatic capillary wall and extend for long distances into the adjoining connective tissue area among the collagen fibers and connective tissue cells. The filaments measure about 100 A in width and have a hollow profile. They exhibit an irregular beaded pattern along their long axis and are densely stained with uranyl and lead. These filaments are similar to the microfibrils of the extracellular space and the filaments observed in the peripheral mantle of the elastic fibers. Infrequently, connections between these various elements are observed, suggesting that the lymphatic anchoring filaments may also contribute to the filamentous units of the extracellular space. It is suggested that these lymphatic anchoring filaments connect the small lymphatics to the surrounding tissues and represent the binding mechansim that is responsible for maintaining the firm attachment of the lymphatic capillary wall to the adjoining collagen fibers and cells of the connective tissue area.


1963 ◽  
Vol 204 (4) ◽  
pp. 655-659 ◽  
Author(s):  
I. MacKay Murray

Intravascular clearance rates of gelatin-stabilized gold were compared with circulating titers of gelatin agglutinins in rats at increasing time intervals after blockading injections of gelatin-stabilized gold and S. marcescens endotoxin. The degree and duration of reticuloendothelial system (RES) blockade against the homologous colloid were directly related to the circulating levels of gelatin agglutinins. In contrast, plasma agglutinins were not decreased in endotoxin-induced blockade against the gelatin-stabilized colloid. In a further experiment, the plasma response to blockading injections of colloidal thorium dioxide, iron oxide, and zymosan was characterized by a transient increase in gelatin agglutinins suggesting the nonspecific release of opsonins from an extravascular source. The findings indicated that clearance rates of gelatin-stabilized colloids were dependent on the total available opsonin in the rat rather than the total circulating opsonin. It is suggested that RES blockade is effected by the prior nonspecific depletion of opsonins from an extravascular reserve which is the major component of the total available opsonin.


2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Vesna R. Stojanović ◽  
Ivan D. Jovanović ◽  
Sladjana Z. Ugrenović ◽  
Ljiljana P. Vasović ◽  
Vladimir S. Živković ◽  
...  

Number of sclerotic glomeruli increases during the aging process. Consequently, majority of remained nonsclerosed glomeruli become hypertrophic and some of them sclerotic, too. The aim of this study was to quantify the size and connective tissue content of nonsclerosed glomeruli and to evaluate the percentage of hypertrophic ones in examined human cases during the aging. Material was right kidney's tissue of 30 cadavers obtained during routine autopsies. Cadavers were without previously diagnosed kidney disease, diabetes, hypertension, or any other systemic disease. Tissue specimens were routinely prepared for histological and morphometric analysis. Images of the histological slices were analyzed and captured under 400x magnification with digital camera. Further they were morphometrically and statistically analyzed with ImageJ and NCSS-PASS software. Multiple and linear regression of obtained morphometric parameters showed significant increase of glomerular connective tissue area and percentage. Cluster analysis showed the presence of two types of glomeruli. Second type was characterized with significantly larger size, connective tissue content, and significantly lower cellularity, in relation to the first type. Such glomeruli might be considered as hypertrophic. First type of glomeruli was predominant in younger cases, while second type of glomeruli was predominant in cases older than 55 years.


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Christina Grove ◽  
Oliver Peschel ◽  
Andreas G. Nerlich

The application of histology to soft tissue remains offers an important technique to obtain diagnostically important information on various physiological and pathological conditions in paleopathology. In a series of 29 cases with mummified tissue ranging between 16 months and c. 5.200 years of postmortem time interval, we systematically investigated paleohistology and the preservation of various tissues. We established a reproducible histological ranking system for the evaluation of mummified tissue preservation. The application of this scheme to the series showed good tissue preservation of tissues with high connective tissue content but also fat tissue and connective tissue rich organs, such as lung tissue, while most other internal organs were less well preserved despite highly different postmortem time intervals. There are some organs with only poor conservation even in short term periods such as the kidneys and CNS. Artificial mummification does not provide better conservation than naturally mummified tissues; “cold” mummies may be much better conserved than those from desert areas. The identification of specific pathologies underlines the potential power of paleohistology.


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Tamilselvan Subramani ◽  
Vidhya Rathnavelu ◽  
Noorjahan Banu Alitheen

Gingival overgrowth is a side effect of certain medications. The most fibrotic drug-induced lesions develop in response to therapy with phenytoin, the least fibrotic lesions are caused by cyclosporin A, and the intermediate fibrosis occurs in nifedipine-induced gingival overgrowth. Fibrosis is one of the largest groups of diseases for which there is no therapy but is believed to occur because of a persistent tissue repair program. During connective tissue repair, activated gingival fibroblasts synthesize and remodel newly created extracellular matrix. Proteins such as transforming growth factor (TGF), endothelin-1 (ET-1), angiotensin II (Ang II), connective tissue growth factor (CCN2/CTGF), insulin-like growth factor (IGF), and platelet-derived growth factor (PDGF) appear to act in a network that contributes to the development of gingival fibrosis. Since inflammation is the prerequisite for gingival overgrowth, mast cells and its protease enzymes also play a vital role in the pathogenesis of gingival fibrosis. Drugs targeting these proteins are currently under consideration as antifibrotic treatments. This review summarizes recent observations concerning the contribution of TGF-β, CTGF, IGF, PDGF, ET-1, Ang II, and mast cell chymase and tryptase enzymes to fibroblast activation in gingival fibrosis and the potential utility of agents blocking these proteins in affecting the outcome of drug-induced gingival overgrowth.


2021 ◽  
Author(s):  
Maisuls Iván ◽  
Yolanda Castro Martin ◽  
Alicia Duran ◽  
Dominic Lariviere ◽  
Pablo Arnal

<p>Fluoride is a natural contaminant of water ⁠that endangers many people worldwide when present in concentrations higher than 2 ppm. Here, fluoride removal by four different nanostructured colloidal particles (SiO<sub>2</sub>@ZrO<sub>2</sub><sup>nc</sup>, SiO<sub>2</sub>@ZrO<sub>2</sub><sup>c</sup>, @ZrO<sub>2</sub><sup>nc</sup>, and @ZrO<sub>2</sub><sup>c</sup>) was measured in batch systems within a period of 24 h. Surprisingly, these materials removed fluoride from the water solutions and reached equilibrium in less than 10 minutes. The combination of high specific surface and fast fluoride removal placed these materials among the top materials currently known in fluoride removal. Also, the impact of element leaching was measured and quantified. The influence of time, pH, and fluoride concentration on leaching of Zr and Si was evaluated with a response surface methodology. Leaching of Zr and Si continued for several hours and depended on first-order, quadratic and cross-product coefficients. Previous studies of fluoride removal with zirconium oxide often assumed that a decrease in fluoride concentration in the solution indicated that fluoride was bound to the surface of the oxide. Zirconium oxide's solubility in water is low, but not zero. Hence, Zr might have formed soluble fluorocomplexes. This is the first report of fluoride removal with zirconium oxide that studied the leaching of the solid to exclude the formation of soluble fluorocomplexes.</p>


Author(s):  
Chandana R ◽  
Kaveen V ◽  
Gajalakshmi M ◽  
Dr. Joshi Manisha S

It is important that during any operation, for the patient to be in an anesthetic condition. The patient won’t feel any pain during the medical procedure using anesthetics and the impact of the anesthesia should be there for as long as the operation goes on. It is also important to measure biomedical parameters such as heart rate and body temperature since these parameters play a vital role. It will create serious health problems if proper dosage of anesthesia is not administered at specified time intervals and to overcome such unfavorable situations this project has been designed to develop an automatic anesthesia control system. Using this, the predefined number of doses can be administered at regular time intervals by simultaneously measuring parameters such as heart rate and temperature.


2000 ◽  
Vol 113 (23) ◽  
pp. 4141-4142
Author(s):  
D.P. Knight

Unconventional Collagens Types VI, VII, VIII, IX, X, XIV, XVI and XIX by S. Ricard-Blum, B. Dublet and M. van der Rest Oxford University Press (2000) pp.155. ISBN 0–19-850545-0 35.00 This thoroughly researched monograph in Oxford University Press's ‘Protein Profile Series’ reviews substantially all the significant literature on this interesting and highly important group of proteins. The authors use the term ‘Unconventional Collagens’ for the collagens of higher vertebrate connective tissues which do not, of themselves, form classical fibrils with a 68 nm banding pattern. The authors chose to omit type IV collagen as this, they claim, would have almost doubled the size of the volume. The monograph represents a very considerable achievement in three respects. Firstly it comprehensively reviews the literature on the sequence, structure, expression, post-translational modification, genetics, physiological function and pathology of each separate unconventional collagen. The thoroughness of this review is indicated by the fact that the bibliography contains no fewer than 1196 references. Secondly, the monograph identifies the modular domain structure for each collagen, clearly demonstrating that these proteins are block co-polymers mainly derived in evolution from a small number of ancestral genes. Thirdly, it starts to identify the way in which the different modules of these sticky molecules interact with each other and with other connective tissue components. This is an important start if we are to understand their vital role in the self-assembly processes which occur in embryology, tissue repair and the major degenerative and collagen gene diseases The clearly written and well set out text is supported by excellent micrographs of rotary shadowed molecules and molecular aggregates and a wealth of diagrams and tables. The book has, in my view, three minor shortcomings: a short summary chapter on type IV would enable the non-specialist reader to relate this collagen to the other non-conventional collagens. Concise summaries at the ends of each chapter would orient newcomers to the field. More significantly, apart from the brief introduction, the book lacks an overall synthesis which pulls together the findings of the separate chapters. These slight limitations aside, this book is essential reading for those engaged in connective tissue research and will do much to stimulate further activity in this area. It will also be of considerable interest to tissue engineers, pathologists and embryologists.


2014 ◽  
Vol 93 (11) ◽  
pp. 1083-1088 ◽  
Author(s):  
O. Carcuac ◽  
T. Berglundh

The aim of the present study was to examine differences in cellular characteristics of human peri-implantitis and periodontitis lesions. Two groups of patients were included: 40 patients with generalized severe chronic periodontitis and 40 patients presenting with severe peri-implantitis. Soft tissue biopsies were obtained from diseased sites (probing pocket depth ≥ 7 mm with bleeding on probing) and prepared for histologic and immunohistochemical analysis. In contrast to periodontitis samples, peri-implantitis lesions were more than twice as large and contained significantly larger area proportions, numbers, and densities of CD138-, CD68-, and MPO-positive cells than periodontitis lesions. Peri-implantitis lesions also extended to a position that was apical of the pocket epithelium and not surrounded by noninfiltrated connective tissue. They further presented with significantly larger densities of vascular structures in the connective tissue area lateral to the infiltrated connective tissue than within the infiltrate. This study suggests that peri-implantitis and periodontitis lesions exhibit critical histopathologic differences, which contribute to the understanding of dissimilarities in onset and progression between the 2 diseases.


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