Bone marrow infiltration

An increase of extrahepatic accumulation of nanocolloid in the bone marrow is seen with hyperplastic bone marrow and with certain hematological disorders (polycytemia, leukemia) (Hofer et al. 1964). In patients with malignant disease, bone marrow scintigraphy may offer early detection of bone marrow infiltration (Hotze et al. 1984 Munz 1984b). 

In cases with diffuse bone marrow infiltration, inhomogeneous osteoporosis can be detected with MDCT. However, as in X-ray diagnostics, this is often hard to... 

While MRI is unsurpassable in the detection of bone marrow infiltration, it does not allow for precise assessment of bone destruction, which is predictive for the risk of fracture. In order to prevent for potentially catastrophic pathologic fracture, it is most important to assess the fracture risk and initiate prophylactic stabi-hzation, if required. MDCT is most useful in the precise assessment of the extent of bony destructions and thereby in the prediction of fracture risk. 

EDI), and water to produce a group of biodegradable PU foams. The interconnected pores varied in size from 10 to 2 mm in diameter. Rabbit bone-marrow stromal cells cultured on the materials for up to 30 days formed multilayers of confluent cells and were phenotypically similar to those grown on tissue culture PS. It supported the adherence and proliferation of both bone-marrow stromal cells and chondrocytes in vitro. In subdermal implants the investigators found that the material showed infiltration of both vascular cells and connective tissue. 

In spite of the above-mentioned similarities between basophils and mast cells, they differ in many other aspects [1,2]. Basophils complete their differentiation within the bone marrow, and mature basophils circulate in the peripheral blood and do not usually infiltrate into peripheral tissues unless inflammation takes place. Mast cells originate from hematopoietic cells in the bone marrow as do basophils, but they mature in peripheral tissues after their bone marrow-derived precursors enter the circulation and migrate into peripheral tissues. Mature mast cells reside in peripheral tissues and do not usually circulate in the peripheral blood. The lifespan of basophils is very short (several days), in contrast to that of mast cells (weeks to months). Basophils do not proliferate once they terminally differentiate whereas mature mast cells keep potential to expand in response to various stimuli. These differences between basophils and mast cells, including distinct anatomical localization, suggest their differential roles in vivo. 

Whereas in children internal organ involvement (systemic mastocytosis, SM) is unusual, MPCM in adults is associated with SM in the majority of cases [10]. WHO criteria for SM consist of the major criterion of multifocal mast cell infiltrates in the bone marrow or other extracutaneous organ(s) and four minor criteria (table 2) [21] 25% or more of mast cells in non-cutaneous biopsy sections with spindle-shaped or abnormal morphology, or... 

Multifocal dense infiltrates of mast cells in bone marrow and/or other extracutaneous organs... 

O The acute leukemias are diseases of bone marrow resulting from aberrant proliferation of hematopoietic precursors. The hallmark of these malignancies is the leukemic blast cell, a visibly immature and abnormal cell in the peripheral blood that often replaces the bone marrow and interferes with normal hematopoiesis. These blast cells proliferate in the marrow and inhibit normal cellular elements, resulting in anemia, neutropenia, and thrombocytopenia. Leukemia also may infiltrate other organs, including the liver, spleen, bone, skin, lymph nodes, and central nervous system (CNS). Virtually anywhere there is blood flow, the potential for extramedullary (outside the bone marrow) leukemia exists. 

Various malignancies can also induce an anaemic state. This is often associated with decreased serum EPO levels, although iron deficiency, blood loss or tumour infiltration of the bone marrow can be complicating factors. In addition, chemotherapeutic agents administered to this patient group often adversely affect stem cell populations, thus rendering the anaemia even more severe. 

Conditions with infiltration of bone marrow Lymphoma Leukemia Myelofibrosis Carcinoma... 

To date, cellular and gene therapy products submitted to FDA have included clinical studies indicated for bone marrow marking, cancer, cystic fibrosis, AIDS, and inborn errors of metabolism and infectious diseases. Of the current active INDs approximately 78% have been sponsored by individual investigators or academic institutions and 22% have also been industry sponsored. In addition to the variety of clinical indications the cell types have also been varied. Examples include tumor infiltrating lymphocytes (TIL) and lymphocyte activated killer (LAK) cells, selected cells from bone marrow and peripheral blood lymphocytes, for example, stem cells, myoblasts, tumor cells and encapsulated cells (e.g., islet cells and adrenal chromaffin cells). 

Adverse effects include nausea, vomiting, diarrhoea, anaphylaxis, hepatic necrosis, fever, bone marrow depression, osteoporosis, menstrual dysfunction, cirrhosis, pulmonary infiltrates and fibrosis, renal toxicity and depigmentation. 

Acute promyelocytic leukemia A form of leukemia involving the infiltration of bone marrow by abnormal pre- and young leukocytes. 

L Splenic marginal zone lymphoma (SMZL). These tumors involve both the white and the red pulp of the spleen. In the white pulp the neoplastic cells surround or replace the germinal centers, often with effacement of the mantle cell zone, and infiltrate the marginal zone. In the red pulp the tumor cells form nodules and sheets and infiltrate the sinuses. The neoplastic lymphocytes may circulate and involve the bone marrow (H5,19). 

As to cryoglobulins, both type I (single component or 1 isotype or subclass of immunoglobulin, or, rarely, a monoclonal light chain) and type II (mixed cryoglobulins with monoclonal IgM as antibody and IgG as antigen) may be present. Nearly 10% of all WM molecules are cryoprecipitable (Kl). Infiltration of bone marrow by tumor cells can result in severe anemia. 

Patients without coexisting multiple myeloma or WM secrete small amounts of M protein (< 10 g/L) and their bone marrow is infiltrated with a lesser percentage of atypical plasma cells similar to that seen in essential monoclonal gammopathy (<10%). 

Adverse effects Its adverse effects include severe nausea and vomiting (centrally mediated). [Note These effects can be diminished by pretreatment with cannabinoids (see p. 243) or pheno-thiazine (see p. 242).] Severe bone marrow depression limits extensive use. Latent viral infections (for example, Herpes zoster] may appear because of immunosuppression. Extravasation is a serious problem. If it occurs, the area should be infiltrated with isotonic sodium thiosulfite to inactivate the drug. 

BMT has been attempted in a number of affected boys with X-ALD. The rationale for the use of BMT in this disorder is that bone marrow-derived cells are known to be capable of degrading VLCFA. Perhaps more important, it was expected that some bone marrow-derived cells would enter the brain since infiltration of the brain with perivascular lymphocytes and macrophages is known to occur. Experience with the procedure has shown that it can stabilize the disease course in a subset of patients, and several cases of reversal of neurological damage also have been reported in patients in the early stages of their disease. 

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