Fizikalni mehanizmi i metode u tumorskim terapijama i prijenosu lijekova do tumora

In addition to several well-known drug delivery strategies developed to facilitate effective chemotherapy with anticancer agents, some new approaches have been recently established, based on specific effects arising from the applications of ultrasound, magnetic and electric fields on drug delivery systems. This paper gives an overview of newly developed methods of drug delivery to tumors and of the related anticancer therapies based on the combined use of different physical methods and specific drug carriers. The conventional strategies and new approaches have been put into perspective to revisit the existing and to propose new directions to overcome the threatening problem of cancer diseases.Osim dobro poznatih metoda prijenosa lijekova u kemoterapijskom pristupu liječenja tumora, nedavno su otkriveni novi načini prijenosa koji se zasnivaju na specifičnim mehanizmima uzrokovanim upotrebom ultrazvuka, magnetskih i električnih polja. Članak sadrži prikaz fizikalnih mehanizama na kojima se temelje ove nove metode, kao i pregled novootkrivenih prijenosnika lijekova (Pluronske micele, magnetoliposomi, magnetski fluidi), novih terapija tumora (magnetska hipertermija, elektrokemoterapija) i najnovijih istraživanja temeljenih na fizikalnom pristupu ovoj problematici

Effects of Dietary N-6/n-3 Ratios On Lipid and Prostaglandin-e2 Metabolism in Rat Gastric-mucosa

The effects of increased dietary n - 3 polyunsaturated fatty acids on gastric mucosal lipid metabolism were studied in rats fed for 8 weeks with different combinations of fish and corn oils. Lipid composition, ex vivo prostaglandin E2 (PGE2) production and enzymatic activities involved in phospholipid metabolism and peroxisomal oxidative catabolism of fatty acids and PGE2 were examined. With dietary n - 6/n - 3 compositional ratios ranging between 75 and 3.3 it was observed that: (i) the arachidonic acid-to-eicosapentaenoic acid ratio (AA/EPA) fell from infinity to 3.1 and 5.1 in phosphatidylcholines (PC) and phosphatidylethanolamines (PE), respectively; (ii) ex vivo production of PGE2 was lowered by a factor of about 2; and (iii) gastric phospholipase A2 activity was enhanced by 32%. With dietary n - 6/n - 3 ratios lower than 3.3, stimulation of PGE2-CoA oxidase activity was observed whilst the PGE2 level remained constant. These data suggest that the fish oil-induced decrease in ex vivo PGE2 production is more closely related to a decrease in the membrane AA level than to an enhanced oxidative catabolism of PGE2

"Fries like" rearrangement: a novel and efficient method for the synthesis of 6-acyl-2(3H)-benzoxazolones and 6-acyl-2(3H)-benzothiazolones

6-Acyl-2(3H)-benzoxazolone and 6-acyl-2(3H)-benzothiazolone derivatives have particularly interesting anti-inflammatory, antiepileptic, analgesic and antiviral properties. in this study, we report an original method of acylation on the 6-position of 2(3H)-benzoxazolone and 2(3H)-benzothiazolone which consists in a two-step procedure involving migration of the acyl group from the N-position to the 6-position of the heterocycle, at 165 degrees C and catalyzed by AlCl3. This new procedure was found to be more efficient with regard to the consumption of AlCl3 and the yield (76-90%) than other acylation methods previously described. (C) 1998 Elsevier Science Ltd. All rights reserved

Synthesis and anticonvulsant activity of 2(3H)-benzoxazolone and 2(3H)-benzothiazolone derivatives.

A series of 2(3H)-benzoxazolone and 2(3H)-benzothiazolone derivatives were synthesized and evaluated for anticonvulsant activity. The compounds were assayed, intraperitoneally in mice and per os in rats, against seizures induced by maximal electroshock (MES) and pentylenetetrazole (scMet). Neurologic deficit was evaluated by the rotarod test. The compounds were prepared to determine the relationship between the 2(3H)-benzoxazolone and 2(3H)-benzothiazolone derivatives' structures and anticonvulsant activity. Several of these compounds showed significant anticonvulsant activity. Compounds 43 and 45 were the most active of the series against MES-induced seizures with ED50 values of 8.7 and 7.6 mg/kg, respectively. Compound 45 displayed good protection against MES-induced seizures and low toxicity in rats with an oral ED50 of 18.6 mg/kg and a protective index (PI = TD50/ED50) of < 26.9. In vitro receptor binding studies revealed that compounds 43 and 45 bind to sigma 1 receptors with nanomolar affinities