Reticuloendothelial tissues

Cells exhibiting storage of birefringent material were found in the parenchyma of liver and spleen, in the adrenals (Scriba 1950), in ganglion cells of the submucous 

The fatty acids of the trihexoside consist to 75% of C22—C24 fatty acids while palmitic and stearic acids together amount to only about 10%. 

It is probable that the stored lipid of ACD occurs normally in small amounts. SvENNERHOLM and SvENNERHOLM (1963) found a trihexoside with a proportion of ceramide glucose galactose of 1 1 2 in plasma and Martens son et al. (1966) found a trihexoside in kidney lipids of normals in addition to dihexoside. 

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Ferritin is detectable in serum. Since the ferritin present in serum is in equilibrium with storage ferritin in reticuloendothelial tissues, the serum ferritin level can be used to estimate total body iron stores. 

Absorption of clofazimine from the gut is variable, and a major portion of the drug is excreted in feces. Clofazimine is stored widely in reticuloendothelial tissues and skin, and its crystals can be seen inside phagocytic reticuloendothelial cells. It is slowly released from these deposits, so that the serum half-life may be 2 months. 

Mycobacterium avium complex Involvement of bone marrow, reticuloendothelial tissues Clarithromycin plus ethambutol rifabutin... 

The mechanisms of antibacterial and anti-inflammatory Ji tiaas of clofazimine are not known. The drug is known to hind to nucleic acids and concentrate in reticuloendothelial tissue. It can also act as an electron acceptor and may inter-ftre with electron transport procc.sscs. 

Phagocytyzed, multiply and spread in lymphatics within WBCs and macrophages to regional lymph nodes, then into bloodstream in systemic acute infection chronic reaction to form granulomas, esp in liver, spleen and other reticuloendothelial tissue, with fibrosis and calcification after healing. 

The accelerated hemoglobin breakdown leads to the release of iron, which accumulates in reticuloendothelial tissue—particularly in the spleen. This iron is usually in the form of hemosiderin (see Hemosiderosis). 

In TD, pathogenetic discussions center around the abnormality of plasma HDL and the deposition of cholesterol esters in reticuloendothelial tissues. Other changes, such as a low plasma level of carotenes in adult cases, apparently result from the decreased concentration of LDL and are, in contrast to those of a-j8-lipoproteinemia, without clinical consequences in TD. Of interest is the existence in the Kentucky kindred of cases with pigmentary retinitis (see fig.[5) such subjects had low or normal plasma HDL, and a relation between the retinopathy and TD is improbable. On the other hand, splenic bone marrow inhibition in one subject is most probably a result of the underlying disease. This has not been established for the occurrence of coronary thrombosis in one patient, in whom an autopsy was not performed and the condition of the vasculature is not known. A predisposition in TD toward the development of atherosclerotic lesions cannot be excluded. 

Blood-forming tissues consist of bone marrow, spleen, lymph nodes and the reticuloendothelial system. These produce the elements of blood and are important for the immunological defense systems. 

Chronic liposome administration in mice Effects on reticuloendothelial function and tissue distribution, J. Pharmacol. Exp. Ther.. 229, 267-275. 

Tissue distribution of lipo-preparations. The tissue distribution of lipid microspheres in normal and pathologic animals was studied. Research into liposomes of similar size suggested that lipid microspheres accumulated preferentially in the reticuloendothelial system, inflammatory sites, or certain tumors. The distribution of lipid microspheres to these tissues has been found in our studies (7,2). Interestingly, our study showed that lipid microspheres accumulated, particularly at high concentrations, in damaged vascular walls such as atherosclerotic vascular walls. 

Free haem groups are ferroporphyrins (cyclic tetrapyrroles). The first reaction of haem catabolism is the release of iron this is followed by the opening of the ring to produce a linear tetrapyrrole called biliverdin. A molecule of carbon monoxide is released as the ring opens. Biliverdin is converted to bilirubin by reduction. These initial reactions may occur in the liver or in other tissues of the reticuloendothelial system, notably the spleen. 

We have shown that polymeric micelles constmcted of block copolymers of poly(ethylene oxide) (PEG) and poly(L-asparate) containing the anticancer dmg (adriamycin, ADR) selectively accumulate at solid tumor sites by a passive targeting mechanism. This is likely due to the hydrophilicity of the outer PEG chains and micellar size (<100 nm) that allow selective tissue interactions [17,18]. Polymeric micelle size ranges are tailored during polymer synthesis steps. Carefully selection of block polymer chemistry and block lengths can produce micelles that inhibit nonselective scavenging by the reticuloendothelial system (RES) and can be utilized as targetable dmg... 

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