Differentiating agents, effects

Figure 3. Effect of chemical differentiating agents on radioactive Bandeiraea simplicifolia [llsI]Iectin binding to mouse neuroblastoma (NlE-115) cell surfaces...

Simpson, R., Lindsay, C.D. (2005). Effect of sulphur mustard on human skin cell lines with differential agent sensitivity. J. Appl. Toxicol. 25 115-28. 

Arsenic is an organic element and a well-known poison that is an effective treatment for acute promyelocytic leukemia (see Table 124—15). As an antineoplastic, arsenic trioxide acts as a differentiating agent, inducing the growth progression of cancerous cells into mature, more normal cells. It also induces programmed cell death or apoptosis. 

Practically, the SE requires the use of polarizing agents with a homogeneous EPR line width and an inhomogeneous spectral width smaller than the nuclear Larmor frequency. These agents can ensure that only one of the forbidden transitions is excited at a time. However, the Differential Solid Effect (DSE, [17]) simultaneously exists and leads to partial or complete cancellation of the polarization effect. 

Although differentiation therapy does not kill cancer cells, it does have the potential to restrain their self-renewal capacity and perhaps increase the efficacy of conventional therapies, which are often most effective on differentiated cells. Furthermore, differentiation agents often have less toxidty than conventional... 

Industrial Shrink-Resist Treatments. Mechanistically, shrink-resist treatments can be divided into degradative and additive types. Degradative treatments use an oxidizing agent to eliminate or reduce the differential friction effect of the fiber simface by modifying or removing the scales. In some cases, a polymer is also applied to the surface to mask the modified scales. The additive approach... 

Cancer. Cancer is a cellular malignancy characterized by loss of normal controls resulting in unregulated growth, lack of differentiation, and the abihty to invade local tissues and metastasize. Most cancers are potentially curable, if detected at an early enough stage. The ideal antineoplastic agent would destroy cancer cells without adverse effects or toxicities to normal cells. No such dmg exists. 

Modem cancer therapy has been primarily dependent upon surgery, radiotherapy, chemotherapy, and hormonal therapy (72) (see Chemotherapeutics,anticancer Hormones Radiopharmaceuticals). Chemotherapeutic agents maybe able to retard the rate of growth, but are unable to eradicate the entire population of neoplastic cells without significant destmction of normal host tissue. This serious side effect limits general use. More recentiy, the immunotherapeutic approach to cancer has involved modification and exploitation of the cellular and molecular mechanisms in host defense, regulation of tissue proliferation, tissue differentiation, and tissue survival. The results have been more than encouraging. 

Cytokines, eg, interferons, interleukins, tumor necrosis factor (TNF), and certain growth factors, could have antitumor activity directiy, or may modulate cellular mechanisms of antitumor activity (2). Cytokines may be used to influence the proliferation and differentiation of T-ceUs, B-ceUs, macrophage—monocyte, myeloid, or other hematopoietic cells. Alternatively, the induction of interferon release may represent an important approach for synthetic—medicinal chemistry, to search for effective antiinflammatory and antifibrotic agents. Inducers of interferon release may also be useful for lepromatous leprosy and chronic granulomatous disease. The potential cytokine and cytokine-related therapeutic approaches to treatment of disease are summarized in Table 4. A combination of cytokines is a feasible modaUty for treatment of immunologically related diseases however, there are dangers inherent in such an approach, as shown by the induction of lethal disserninated intravascular coagulation in mice adrninistered TNF-a and IFN-y. 

Another clinical consideration is the abiUty of local anesthetic agents to effect differential blockade of sensory and motor fibers. In surgical procedures such as obstetrics or postoperative pain rehef, an agent which produces profound sensory block accompanied by minimal motor block is desirable. On the other hand some procedures such as limb surgery require both deep sensory and motor blockade. In clinical practice, bupivacaine ( 22,... 

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