The Histologic Host Response to Liquid Silicone Injections for Prevention of Pressure-Related Ulcers of the Foot

2004 ◽  
Vol 94 (6) ◽  
pp. 550-557 ◽  
Author(s):  
William Dean Wallace ◽  
S. W. Balkin ◽  
Leo Kaplan ◽  
Scott Nelson

This study analyzed the histologic effects of and host response to subdermally injected liquid silicone to augment soft-tissue cushioning of the bony prominences of the foot. A total of 148 postmortem and surgical specimens of pedal skin with attached soft tissue were obtained from 49 patients between July 1, 1974, and November 30, 2002. The longest period that silicone was in vivo was 38 years. The specimens were then processed into paraffin blocks and examined for specific findings. The variables considered included distribution of silicone within the tissue, host response, migration to regional lymph nodes, and viability of the host tissue after treatment. The host response to silicone therapy consisted primarily of delicate-to-robust fibrous deposition and histiocytic phagocytosis, with eventual formation of well-formed elliptic fibrous pads. The response in the foot appears different from that in the breast and other areas of the body previously studied. No examples of granulomas, chronic lymphoplasmacytic inflammation, or granulation tissue formation were seen, with only rare foreign-body giant cells present. Silicone injections in fat pads for the treatment of atrophy and loss of viable tissue show a histologically stable and biologically tolerated host response that is effective, with no evidence of any systemic changes. (J Am Podiatr Med Assoc 94(6): 550–557, 2004)

2021 ◽  
Author(s):  
Arnat Balabiyev ◽  
Nataly P. Podolnikova ◽  
Jacquelyn A. Kilbourne ◽  
D. Page Baluch ◽  
David Lowry ◽  
...  

ABSTRACTImplantation of biomaterials and medical devices in the body triggers the foreign body reaction (FBR) which is characterized by macrophage fusion at the implant surface leading to the formation of foreign body giant cells and the development of the fibrous capsule enveloping the implant. While adhesion of macrophages to the surface is an essential step in macrophage fusion and implanted biomaterials are known to rapidly acquire a layer of host proteins, a biological substrate that is responsible for this process in vivo is unknown. Here we show that mice with genetically-imposed fibrinogen deficiency display a dramatic reduction of macrophage fusion on implanted biomaterials and are protected from the formation of fibrin-containing granulation tissue, a precursor of the fibrous capsule. Furthermore, macrophage fusion on biomaterials implanted in FibAEK mice that express a mutated form of fibrinogen incapable of thrombin-mediated polymerization was strongly reduced. Surprisingly, despite the lack of fibrin, the capsule was formed in FibAEK mice, although it had a different composition and distinct mechanical properties than that in wild-type mice. Specifically, while mononuclear α-SMA-expressing macrophages embedded in the capsule of both strains of mice secreted collagen, the amount of collagen and its density in the tissue of FibAEK mice was reduced. These data identify fibrin polymer as a key biological substrate driving the development of the FBR.


1991 ◽  
Vol 252 ◽  
Author(s):  
Reynaldo Todescan ◽  
Johne E. Davies

ABSTRACTUsing both in vivo and in vitro experiments we have demonstrated that: reconstituted collagen will undergo mineralization in a healing bony compartment; that this mineralization is the result of spontaneous precipitation of calcium salts due to the presence of alkaline phosphatase produced by the bone cells, and that once calcified, the collagen will undergo cellular resorption by tartrate-resistant multi-nucleate giant cells similar to osteoclasts. This sequence of events is quite different to that in the supra-bony soft-tissue compartment where no calcification of the collagen is apparent, the collagen matrix becomes infiltrated with fibroblast-like cells and little resorption of the matrix occurs during implantation.We conclude that reconstituted collagen may be employed as both a tissue barrier, enhancing guided tissue regeneration, and a bone-substitute material, which becomes replaced by natural bone tissue.


2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Mayra Silva Miranda ◽  
Adrien Breiman ◽  
Sophie Allain ◽  
Florence Deknuydt ◽  
Frederic Altare

One of the main features of the immune response toM. Tuberculosisis the formation of an organized structure called granuloma. It consists mainly in the recruitment at the infectious stage of macrophages, highly differentiated cells such as multinucleated giant cells, epithelioid cells and Foamy cells, all these cells being surrounded by a rim of lymphocytes. Although in the first instance the granuloma acts to constrain the infection, some bacilli can actually survive inside these structures for a long time in a dormant state. For some reasons, which are still unclear, the bacilli will reactivate in 10% of the latently infected individuals, escape the granuloma and spread throughout the body, thus giving rise to clinical disease, and are finally disseminated throughout the environment. In this review we examine the process leading to the formation of the granulomatous structures and the different cell types that have been shown to be part of this inflammatory reaction. We also discuss the differentin vivoandin vitromodels available to study this fascinating immune structure.


2007 ◽  
Vol 33 (Supplement) ◽  
pp. S186-S192
Author(s):  
EDUARDO ZAPPI ◽  
JAY G. BARNETT ◽  
MARCELO ZAPPI ◽  
CHANNING R. BARNETT

2021 ◽  
Vol 11 (2) ◽  
pp. 212-215
Author(s):  
Mariya Zatolokina ◽  
Ekaterina Mishina ◽  
Alexander Sozykin ◽  
Marina Gorbunova ◽  
Alexander Alekseev

Background: The purpose of our work was determined by the accumulation of a significant amount of experimental material under the conditions of implantation of a foreign body, a mesh implant, into the region of the anterior abdominal wall in order to obtain experimental inflammation, in which foreign body giant cells (FBGCs) were constantly visualized as reactive formations. This research aimed to study the dynamics of morphological changes in FBGCs under conditions of experimental implantation of a foreign body, a mesh implant, and the possible mechanism of their formation Methods and Results: This study was carried out on male Wistar rats, in which a foreign body was implanted—a mesh endoprosthesis made of polypropylene—in the region of the anterior abdominal wall under the aponeurosis of the rectus abdominis muscles. A section of the anterior abdominal wall with the implanted endoprosthesis was excised on Days 10, 21, 30, and 60 after surgery, fixed in 10% buffered formalin solution. The obtained samples were embedded in paraffin according to standard prescriptions; histological sections with a thickness of 5-7µm were made and stained with H&E, according to the methods of Van Gieson and Mallory, and an immunohistochemical study was performed using the marker of cell proliferation (Ki-67). The revealed structural features of multinucleated cells were recorded by microphotography using a photo attachment and a Levenhuk video camera (USA). During the study, it was revealed that the amount, functional activity and morphological diversity of FBGCs gradually increased, reaching a maximum by Day 30 of the experiment. At a later date, some of them died, while the remaining part was differentiated, splitting into small multinucleated cells and mononuclear elements, morphologically identical to macrophages and fibroblasts. The formation of FBGCs continued as long as the mesh implant was in the body. Conclusion: FBGCs are reactive formations that arise in response to various endo- and exogenous irritation.


2012 ◽  
Vol 82 (3) ◽  
pp. 228-232 ◽  
Author(s):  
Mauro Serafini ◽  
Giuseppa Morabito

Dietary polyphenols have been shown to scavenge free radicals, modulating cellular redox transcription factors in different in vitro and ex vivo models. Dietary intervention studies have shown that consumption of plant foods modulates plasma Non-Enzymatic Antioxidant Capacity (NEAC), a biomarker of the endogenous antioxidant network, in human subjects. However, the identification of the molecules responsible for this effect are yet to be obtained and evidences of an antioxidant in vivo action of polyphenols are conflicting. There is a clear discrepancy between polyphenols (PP) concentration in body fluids and the extent of increase of plasma NEAC. The low degree of absorption and the extensive metabolism of PP within the body have raised questions about their contribution to the endogenous antioxidant network. This work will discuss the role of polyphenols from galenic preparation, food extracts, and selected dietary sources as modulators of plasma NEAC in humans.


1991 ◽  
Vol 30 (01) ◽  
pp. 35-39 ◽  
Author(s):  
H. S. Durak ◽  
M. Kitapgi ◽  
B. E. Caner ◽  
R. Senekowitsch ◽  
M. T. Ercan

Vitamin K4 was labelled with 99mTc with an efficiency higher than 97%. The compound was stable up to 24 h at room temperature, and its biodistribution in NMRI mice indicated its in vivo stability. Blood radioactivity levels were high over a wide range. 10% of the injected activity remained in blood after 24 h. Excretion was mostly via kidneys. Only the liver and kidneys concentrated appreciable amounts of radioactivity. Testis/soft tissue ratios were 1.4 and 1.57 at 6 and 24 h, respectively. Testis/blood ratios were lower than 1. In vitro studies with mouse blood indicated that 33.9 ±9.6% of the radioactivity was associated with RBCs; it was washed out almost completely with saline. Protein binding was 28.7 ±6.3% as determined by TCA precipitation. Blood clearance of 99mTc-l<4 in normal subjects showed a slow decrease of radioactivity, reaching a plateau after 16 h at 20% of the injected activity. In scintigraphic images in men the testes could be well visualized. The right/left testis ratio was 1.08 ±0.13. Testis/soft tissue and testis/blood activity ratios were highest at 3 h. These ratios were higher than those obtained with pertechnetate at 20 min post injection.99mTc-l<4 appears to be a promising radiopharmaceutical for the scintigraphic visualization of testes.


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