Drugs cytostatic

Anticancer diugs Cytostatic drugs Cytotoxic drags Antitumor drags... 

II cleaves the two complementary strands of DNA four base pairs apart and the resulting 5 -phosphoryl groups become covalently linked to a pair of tyrosine groups, one in each half of the dimeric topoisomerase II enzyme. Several groups of drugs are known that selectively inhibit topoisomerases in bacteria (quino-lones) or mammalian cells (etoposide, tenoposide). Quinolones are used to treat bacterial infections inhibitors of mammalian topoisomerases are cytostatic drugs used for the treatment of cancer. 

Cytomegalovirus CMV Cytoplasmic Tyrosine Kinases Cytoskeleton Cytostatic Drugs... 

Cytostatic drugs for which inhibitors are primarily needed are often not only substrates of P-gp but also inducers of P-gp overexpression with one or even several type II units. An important point to clarify would be whether or not type II units are required to achieve a cytostatic effect. If they were not required, it might be possible to eliminate the P-gp-inducing effect that causes multidrug resistance by eliminating type II units. So far, the only other possibility of overcoming multidrug resistance is to inhibit the transporters involved. Inhibition can be achieved essentially by two different concepts ... 

M. J. Monte, M. R. Ballestero, O. Briz, M. J. Perez and J. J. G. Marin, Proapoptotic effect on normal and tumour intestinal cells of cytostatic drugs with enterohepatic organotropism, J. Pharmacol. Exp. Ther., 2005, 315, 24. 

Lenz K, Mahnik SN, Weissenbacher N, Mader RM, Krenn P, Harm S, Koellensperger G, Uhl M, Knasmuller S, Ferk F, Bursch W, Fuerhacker M (2007) Monitoring, removal and risk assessment of cytostatic drugs in hospital wastewater. Water Sci Technol 56 141-149... 

THF derivatives in the biosynthesis of DNA precursors, the enzymes involved in THF metabolism are primary targets for cytostatic drugs (see p. 402). 

The coenzyme tetrahydrofolate (THF) is the main agent by which Ci fragments are transferred in the metabolism. THF can bind this type of group in various oxidation states and pass it on (see p. 108). In addition, there is activated methyl, in the form of S-adenosyl methionine (SAM). SAM is involved in many methylation reactions—e. g., in creatine synthesis (see p. 336), the conversion of norepinephrine into epinephrine (see p. 352), the inactivation of norepinephrine by methylation of a phenolic OH group (see p. 316), and in the formation of the active form of the cytostatic drug 6-mercaptopurine (see p. 402). 

The DNA component deoxythymidine triphosphate (dTTP) is synthesized from UDP in several steps. The base thymine, which only occurs in DNA (see p. 80), is formed by meth-ylation of dUMP at the nucleoside monophosphate level. Thymidylate synthase and its helper enzyme dihydrofolate reductase are important target enzymes for cytostatic drugs (see p. 402). 

A frequently used procedure is targeted irradiation with y-rays, which block cell reproduction due their mutagenic effect (see p. 256). Another approach is to inhibit cell growth by chemotherapy. The growth-inhibiting substances used are known as cytostatic drugs. Unfortunately, neither radiotherapy nor chemotherapy act selectively—i. e., they damage normal cells as well, and are therefore often associated with severe side effects. 

Antimetabolites are enzyme inhibitors (see p. 96) that selectively block metabolic pathways. The majority of clinically important cytostatic drugs act on nucleotide biosynthesis. Many of these are modified nucleobases or nucleotides that competitively inhibit their target enzymes (see p. 96). Many are also incorporated into the DNA, thereby preventing replication. 

The cytostatic drugs administered (indicated by a syringe in the illustration) are often not active themselves but are only converted into the actual active agent in the metabolism. This also applies to the adenine analogue 6-mercaptopurine, which is initially converted to the mononucleotide tIMP (thioinosine monophosphate). Via several intermediate steps, tIMP gives rise to tdGTP, which is incorporated into the DNA and leads to crosslinks and other anomalies in it. The second effective metabolite of 6-mercaptopurine is S-methylated tIMP, an inhibitor of amidophos-phoribosyl transferase (see p. 188). 

Lelieveld P, Scoles MA, Brown JM, Kallmann RF. The effect of treatment in fractionated schedules with the combination of x-irradiation and six cytostatic drugs on the RIF-1 tumor and normal mouse skin. Int J Radiat Oncol Biol Phys 1985 11 111-121. 

The blood-CSF barrier is relatively permeable to hydrophilic macromolecules, (i.e., ai-macroglobulin and IgM). In addition, the passage of smaller molecules, which are larger than 500 Da, is facilitated by lipophilicity (i.e., by antibiotics and cytostatic drugs). The composition of the extracellular fluid of the brain parenchyma is unknown. It resembles CSF only in a narrow margin of a few millimeters adjacent to the free CSF space, a zone where a limited diffusion of water-soluble molecules is possible (F2). The composition of CSF is well known because the subarachnoid space can be tapped at its lowest point. Despite the great distance from the site of production, the choroid plexus, it shows all of the characteristics of a filtrate, even in the lumbar sac. 

Laparoscopic catheterization of the ronnd ligament of liver was condncted in 16 patients. Catheterization of the cellnlar tissne of the ronnd ligament was performed by its centesis with a thin trocar at the point of projection of the ligament on the anterior abdominal wall and gniding of the catheter with 1-2 mm diameter to the depth of 5-7 cm. With snbseqnent introdnction into the cellular tissue of the round ligament in a single step or by drops of 0.25% solution of novocaine, broad-spectrum action antibiotics, spasmolytic, antihistamine and anti-enzymatic preparations and cytostatic drugs in qnantities determined by the severity of the disease. The duration of catheterization was 6 1 days. 

Margarete studied pharmacy at the Faculty of Natural Sciences, University of Vienna, from 1995 to 2001. In her master thesis she engaged in the synthesis of cytostatic drugs. After graduation, she underwent professional training to be pharmacist. In addition to working at a pharmacy, she studies at the Vienna University of Economics and Business Administration. 

Hermel, M., Heckelen, A., Kirchhof, B., Schrage, N.F. Inhibitory effect of ascorbic acid on human retinal pigment epithelial cell proliferation compared to cytostatic drugs-influence of histamine. Inflamm Res 50(Suppl 2), S93-S95... 

Tamoxifen is commonly used in the treatment of breast carcinoma (1) the overall rates published for adverse effects vary very greatly, between 1 and 60% (2,3). It has also been used as a form of HRT to reduce bone loss and the incidence of fractures in high-risk cases (4). A combination of tamoxifen with ovarian suppression is as effective as the use of cytostatic drugs, and has been claimed to be better tolerated (5-7). 

The authors did not make it clear whether cytostatic drugs, which can cause alopecia, were also used, but it is striking that there have been several earlier reports of baldness with tamoxifen. 

Combined cytostatic drug therapy for Hodgkin s disease in childhood often results in abnormal endocrine function, particularly increases in follicle-stimulating hormone, prolactin, and thyroid-stimulating hormone (318). 

Schwendener, R. A. (1986). The preparation of large volumes of homogeneous, sterile liposomes containing various lipophilic cytostatic drugs by the use of a capillary dialyBancer Drug Deliv., 3, 123-129. 

Many modern pharmaceutical and biological products, e.g. blood derivatives, vaccines, cytostatic drugs, antibiotics, bacteria cultures but also consumer goods such as soluble coffee are freeze-dried to transform perishable substances into a form that can be stored and reconstituted to their almost original stale without loss of quality. 

K. Hemminki, P. Kyyrdnen and M-L. Lindbohm. Spontaneous abortions and malformations in the offspring of nurses exposed to anesthetic gases, cytostatic drugs and other potential health hazards in hospitals based on registered information of outcome. J. Epid. Comm. Health 39, 1985, 141. 

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