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BACKGROUND Metastatic malignant melanoma belongs to a group of cancers with high mortality. In recent years, advances in our knowledge of the pathogenesis of melanoma and the discovery of new drugs has resulted in significant progress in the treatment of metastatic malignant melanoma patients. The development of resistance to these drugs, however, remains a challenge. One way how to avoid resistance, or at least delay it, is to administer combination therapy. OBSERVATION AND CONCLUSION This case study demonstrates that combination therapy with a BRAF and a MEK inhibitor can be used to successfully treat metastatic malignant melanoma patients and suggests they should be employed in therapeutic algorithms for patients with metastatic malignant melanoma and BRAF gene mutations.

The B-RAF kinase is among major targets of biological therapy of cancer. B-RAF acts in the MAP kinase pathway, being activated by any of the RAS G-proteins. Hyperactive B-RAF is typically detected in chemoresistant and radioresistant malignant metastatic melanoma. In this study, we focus on the reversible ATP-competitive inhibitor dabrafenib (GSK-2118436), which is now in phase III clinical trial for use in subjects with various cancers expressing hyperactive B-RAF. Dabrafenib is selective for B-RAFV600E and B-RAFV600K (less for B-RAFV600D) over wild-type B-RAF. Thus, similarly to vemurafenib (Zelboraf), suggested is mandatory pre-screening for activating B-RAF mutations in the cancer tissue of each subject. Dabrafenib inhibits neoplastic growth at concentrations 53.8 nM in plasma, which corresponds to 30 mg/kg qd p.o., or to --- 3 mg/kg qd i.v. Most of the cancers expressing hyperactive B-RAF respond to dabrafenib treatment, but the complete response is only rarely achieved. Toxic side effects include skin lesions, pyrexia, frequent fatigue, nausea and pain. Resistance to dabrafenib is frequently developed via de novo RAS mutations, leading to the disease relapse. The RAS G-protein is capable of signaling downstream not only through B-RAF, but also through closely related C-RAF, which circumvents the effects of the B-RAF inhibitor. Thus, dabrafenib should not be prescribed to subjects with neoplasias that are positive for activating RAS mutations. Since B-RAF mutations alone cause only the formation of benign naevi, since the tumors frequently and quickly acquire resistance to B-RAF inhibitors, and because the B-RAF-inhibitor-mediated treatment outcomes are severely affected by changes in the activity and expression of a number of signaling molecules (among them PI3K/mTOR, PTEN, AKT, MEK, PDGFRβ), it can be anticipated that dabrafenib treatment should be suggested only as a part of combined therapy targeting simultaneously the other pathways responsible for cancer onset and progression.

Reactivators of acetylcholinesterase inhibited by organophosphate inhibitors play an important role in organophosphate poisoning therapy. There are a large number of reactivators being tested for their ability of penetration through blood-brain barrier (BBB) nowadays. The main aim of this thesis is to test this ability in four well know reactivators {--} HI-6, K-027, K-074 and TO-032. The 5% lethal dose (LD50) {--} therapeutic dose - of each reactivator was i.m. (intramuscularly) applied to experimental animals (Wistar rats) into right posterior thighs. Then the animals were sacrificed and the blood (plasma) and brain were collected for HPLC analysis. Subsequently, brain and plasma were frozen at -80 °C and stored until the assay. The reactivator concentrations were measured in plasma and four parts of the brain {--} frontal cortex (FC), basal ganglia (BG), ponto-medullar part (PM) and cerebellum (Ce). There were five animals for each group used for the purpose of the experiment. The concentrations of reactivators in plasma and blood samples were measured using HPLC-UV/VIS methodology. HI-6 concentrations CFC were on the average 4.29% of Caverage in plasma, CBG were on the average 1.9% of Caverage in plasma, CPM were on the average 2.3% of Caverage in plasma, and CCe were on the average 1.85% of Caverage in plasma. These rates were counted from all concentrations within the scope of particular observed parts of the brain. All the other tested reactivators were not quantified in brain at all.

To present a review of a novel transdermal contraceptive patch containing norelgestromin (150 micrograms/d) and ethinylestradiol (20 micrograms/d).Review article.Department of Gynecology and Obstetric, 1st Medical Faculty and General Faculty Hospital, Prague.The contraceptive patch exhibits favourable pharmakokinetic profile, maintaining efficacious serum hormone concentrations under varying conditions and without peaks and through characteristic of oral dosing. Efficacy, cycle control, tolerability and side effect profile were comparable to an established oral contraceptive. Compliance with the weekly administered contraceptive patch was significantly better than with an oral contraceptive. The reliability of adhesion of the patch is very high and consistent even under varying conditions (heat, humidity, exercise).

The currently used antidotal treatment of intoxication with nerve agents, consisting of an anticholinergic drug and an acetylcholinesterase reactivator, is often completed with the anticonvulsive drug diazepam to prevent poisoned organisms from centrally mediated seizures and subsequent tonic-clonic convulsions. The aim of this study was to find out whether the complementation of the antidotal treatment with diazepam can influence antidotal treatment-induced elimination of acute lethal effects of the chosen nerve agent--soman.In experiments on mice, the values of medium lethal dose of soman in the case of 24 h surviving of soman-exposed mice, treated with the basic antidotes involving various types of anticholinergic drugs and acetylcholinesterase reactivators, were evaluated and compared to the values of medium lethal dose of soman in mice treated with antidotes completed with diazepam. Our findings confirm that diazepam is able to enhance the efficacy of basic antidotal treatment to eliminate acute lethal effects of soman if atropin is used as anticholinergic drug. On the other hand, no ability of diazepam to enhance soman-induced lethal effects was demonstrated if an anticholinergic drug with central effects such as benactyzine, biperiden or scopolamin was used. The ability of diazepam to influence the efficacy of antidotes to eliminate soman-induced acute lethal effects was only observed in the case of using the oxime HI-6 as acetycholinesterase reactivator.The most perspective antidotal mixture against soman, consisting of the oxime HI-6 and atropine, should be complemented by diazepam no only because of the prevention of poisoned organisms from centrally mediated seizures and subsequent tonic-clonic convulsions but also because of the increase in the ability of antidotal treatment to eliminate soman-induced acute lethal effects.

In experiments on male rats the paper investigated the effect of pharmacological prophylaxis with Panpal (pyridostigmine in combination with benactyzine and trihexyphenidyl) on the activity of acetylcholinesterase in the whole blood, diaphragm, and selected parts of the brain (frontal cortex, pontomedular region, hippocampus, cerebellum) at hour 1 and 3 of untreated and treated (oxime HI-6 with atropine) intoxication with the organophosphorous insecticide phosdrine. Whereas in the CNS Panpal did not produce statistically significant changes in the activity of acetylcholinesterase in the course of untreated and treated phosdrine intoxication, in the blood and diaphragm Panpal markedly intensified phosdrine-induced inhibition of the acetylcholinesterase activity and, in addition, decreased the reactivating effect of the oxime HI-6. The data give evidence of the importance of the combination of the prophylactically used reversible acetylcholinesterase inhibitor pyridostigmine with anticholinergics, which could eliminate the consequences of a pyridostigmine-induced decrease in the activity of the enzyme in the periphery.

The composition of the causal antidotal therapy of subjects, poisoned with organophosphorus insecticides, has not been satisfactorily solved till now in spite of the knowledge of the basic mechanism of action of these toxic substances. The purpose of this study is to evaluate which of currently used or perspective acetylcholinesterase reactivators seems to be the most efficacious to protect poisoned subjects.In experiments on white laboratory rats, the reactivating efficacy of selected acetylcholinesterase reactivators (oximes), administered at equimolar doses, was evaluated in target tissue of toxic effects of organophosphorus insecticides (diaphragm, brain) and compared with their therapeutic efficacy in the case of prophylactic administration with the help of the evaluation of mean efficacy dose of oximes, possible to protect rats exposed to supralethal dose of organophosphorus insecticide fosdrin for 24 hours. Our findings confirm that there are not statistically significant differences in reactivating and therapeutic efficacy of oximes tested against fosdrin in rats.The perspective acetylcholinesterase reactivators (H oximes) seem to be as suitable as currently used oximes for the therapy of acute poisonings with organophosphorus insecticides although they are not significantly more efficacious than currently used oximes as in the case of the treatment of poisoning with highly toxic organophosphorus compounds.

Acute poisoning with the highly toxic organophosphorus agent, soman, is not treated satisfactorily even by the most modern antidotes.In experiments on rats, the reactivating effect of a new asymmetric bispyridinium oxime BI-6 was compared with widely used oximes HI-6 and obidoxime by investigating the changes of soman-inhibited acetylcholinesterase activity in the diaphragm and various parts of the brain in rats up to three hours following soman challenge. Our findings confirm that the new oxime BI-6 is a more effective reactivator of soman-inhibited acetylcholinesterase than obidoxime but not as effective as the oxime HI-6 especially in the peripheral compartment.The new oxime BI-6 is not as effective as HI-6 which seems to have definite advantages over other oximes in the treatment of soman poisoning.

The therapeutic efficacy of the new asymmetric bispyridinium oxime BI-6 against acute toxicity of the highly toxic organophosphate soman and the organophosphorus insecticide fosdrin by means of affecting the LD50 values of these noxiores substances was compared with the effect of the hitherto most perspective oxime HI-6 and the classic obidoxime always in combination with the identical dose of atropine. At the equimolar level the effect of oxime BI-6 against fosdrin completely equals the effects of both oximes HI-6 and obidoxime. The effect of oxime BI-6 against soman is even more marked than the effect of HI-6 but this difference is not statistically significant. On the other hand, at the equi-effective level, the effect of oxime BI-6 against soman is statistically significantly lower than the effect of HI-6, and against fosdrin it is even lower than the effect of both remaining oximes. The effects of the new oxime BI-6 equal, or slightly exceed the therapeutic effect of HI-6 but at the equimolar level only. At the equi-effective level which respects the toxicity of the oxime and is therefore more important for practical use, it is a therapeutically weaker reactivator of acetylcholinesterase than HI-6.

The pharmacological prophylaxis protecting the organism against organophosphorus compounds could increase the effect of antidotal treatment of poisoning with organophosphates.The influence of the pharmacological prophylaxis with Panpal (pyridostigmine in combination with benaetyzine and trihexyphenidyle) on acetylcholinesterase activity in diaphragm and various parts of brain at 1 and 3 h following non-treated and treated (the oxime HI-6 in combination with atropine) soman poisoning was tested on male rats. While Panpal did not significantly influence the acetylcholinesterase activity in brain following non-treated as well as treated soman poisoning. Panpal increased so many-induced acetylcholinesterase inhibition following non-treated poisoning and decreased the reactivating effect of the oxime HI-6 following treated soman poisoning in diaphragm.Our data confirm the importance of the combination of reversible acetylcholinesterase inhibitor pyridostigmine with anticholinergic drugs in the pharmacological prophylaxis of soman poisoning because of the elimination of consequences of pyridostigmine-induced increasing in acetylcholinesterase inhibition in the peripheral compartment.

In experiments on male rats the reactivating effects of oxime HI-6 and obidoxime in combination with atropine on acetylcholinesterase, inhibited by the highly toxic organophoshate cyclosin, were compared in various parts of the brain (frontal cortex, pontomedullar region, hypothalamus, hippocampus, basal ganglia) and the diaphragm. After intramuscular administration of cyclosine in a sublethal dose, a medium-serious inhibition of the diaphragmatic acetylcholinesterase and a various inhibition of this enzyme in the brain with the maximum in the frontal cortex took place in the first hours of intoxication. The subsequent antidotal therapy resulted in variously high reactivation of cyclosin-inhibited acetylcholinesterase in dependence on the selection of oxime. Practically in all regions under study, a significantly more marked reactivation of the given enzyme in the therapy of intoxication with oxime HI-6 was recorded. For the therapy of acute intoxications with highly toxic cyclosin, oxime HI-6 seems to be a more suitable reactivator of acetylcholinesterase than the hitherto used obidoxime.

Causal antidotal therapy of acute intoxications with organophosphorus compounds involving administration of the parasympatholytic and cholineesterase reactivator (oxime) has not been resolved so far satisfactorily despite knowledge of the basic mechanism of action of these noxious substances.In experiments on mice the therapeutic effect of parasympatholytics atropine, benactyzine and biperidene (Akineton) combined with oxime HI-6 on the toxicity of highly toxic organophosphates soman and substance VX and the organophosphorus insecticide phosdrine was compared as regards their influence on the LD50 of these noxious substances during 24-hour survival of experimental animals. Two levels of antidotes were tested. These findings confirm that the LD50 value of untreated intoxication with all three organophosphorus compounds is most increased by oxime HI-6 combined with benactyzine regardless of the antidote dosage.Oxime HI-6 is the most effective against highly toxic organophosphates and organophosphorus insecticides when combined with the centrally acting parasympatholytic benactyzine.

In experiments on male mice, the effect of the cholinesterase reactivators obidoxime, methoxime and HI-6 in combination with atropine sulfate on the acute intoxication with the organophosphorous insecticide fosdrine was tested in dependence on the period of administration of drugs after intoxication and on the dose of oxime by influencing the LD50 value in 48-hour survival of experimental animals. It has been demonstrated that the rate of the therapeutic intervention is a much more important factor influencing the effect of oximes than the dose of oximes. A shortening of the period of drug administration from 2 minutes to 30 seconds substantially increases the effects of all three oximes. A comparison of the effects of all three reactivators has shown that the oxime HI-6 is significantly more effective than the remaining two reactivators in the case of therapy of intoxication 30 seconds after the application of the noxa. In the therapy of intoxication 2 minutes after the exposure of experimental animals to fosdrine, the effect of the antidotal therapy was relatively low regardless of the selected oxime.

In experiments on male rats, the effect of selected cholinolytic agents (atropine, benactyzine, G 3063) in combination with the reactivator of cholinesterases HI-6 on the cholinergic and non-cholinergic effects of GV substance in the course of acute sublethal intoxication was compared. The cholinergic affects of GV substance were examined by means of the changes in the activity of cholinesterases in whole blood, the CNS, diaphragm and liver, the noncholinergic stressogenic effects by means of the changes in the level of corticosterone in plasma and the activity of tyrosine amino transferase in the liver. It follows from the changes in the activity of cholinesterases that the cholinergic effects of GV substance are least influenced by atropine, whereas benactyzine and G 3063 exert an approximately similar effect. The difference in the effect is evident especially in the 24th hour of intoxication. Similarly stressogenic effects of GV substance are least influenced by an antidotal combination of atropine and HI-6. It means that the centrally acting cholinolytic agents benactyzine and G 3063 are more advantageous for the therapy of GV substance poisonings than the peripherally acting atropine.

The author presents an account of the development of scintigraphic methods in the detection of inflammatory processes of the musculoskeletal system. The original method used in vitro 111In labelled separated leucocytes. It was improved by the possibility to label leucocytes by means of HMPAO 99mTc. In vivo leucocytes can be labelled by means of monoclonal antibodies. Nanocolloid offers similar possibilities as regards use and gives a good yield. Its use is simple and the preparation is available. Scintigraphy with nanocolloid must be considered nowadays the first scintigraphic method used when an inflammatory process is suspected, in particular of the extremities. Scintigraphy with nanocolloid can differentiate in planned revision alloplasty septic and aseptic loosening. The mentioned finding can be used for planning, implementation and ensuring the operation. The author was able, in collaboration with the department of nuclear medicine, to test scintigraphy with nanocolloid in five patients with complains after alloplasty of obscure origin. Patients' data are listed in table a and two cases are discussed in more details.

The antibacterial efficacy of two novel beta-lactam antibiotics of the oxime type, VUFB 16265 and 16272, was evaluated by determining the minimal inhibitory concentration (MIC) in 47 clinical strains and 6 standard strains (Staphylococcus aureus, Streptococcus pyogenes and faecalis, E. coli, Enterobacter and Proteus spec., Pseudomonas aeruginosa), which were the most frequent causes of infectious complications. The results were compared with the MIC of cefalexin, cefoxitin, cefazolin, cefsulodin, and ampicillin. The antibacterial activity of both VUFB drugs was comparable with the efficacy of the antibiotics tested. Only in the strains of Pseudomonas aeruginosa the activity of all antibiotics under evaluation was low and only cefsulodin was effective.

Per os intoxication of sheep with O-ethyl S-(2-dimethylaminoethyl)methyl phosphonium thioate (EDMM) in the dose of 0.209 mg per kg of live weight, that means p.o. LD50 (2 h), can be therapeutically mastered by means of an antidotal mixture of the reactivator of cholinesterase (trimedoxim) and of the cholinolytic (atropine), which is commercially available in the SPOFA preparation TMB-4 compos. for human purposes, if the effective dose of the reactivator was 10.0 mg per kg of live weight and if it was applied intravenously, and if the dose of the cholinolytic consisted, per 1 kg of live weight, of 0.08 mm. The antidotal mixture was applied, when the degree of the muscarinic and nicotinic symptoms and the corresponding degree of the inhibition of erythrocytary and plasmatic cholinesterase were on such a level which, according to the classification criteria, we consider a severe grade of intoxication with a dubious diagnosis.

Sheep were studied for the possibility of treatment after parenteral (intramuscular) intoxication with EDMM (methylthiophosphorous acid O-ethyl-S-2-dimethylamino-ethylester) and with EDIM (methylthiophosphorous acid O-ethyl-S-2-diisopropyl-aminoethylester). In both cases of intoxication, the therapy was based on a system of an anticholinergic and cholinesterase reactivator administered singly at a time of the maximum development of the clinical signs of poisoning and maximum inhibition of both erythrocytic (AChE, E.C.3.1.1.7.) and plasma (BChE, E.C.3.1.1.8.) cholinesterase. The optimum therapeutic system requires the administration of 20.0 mg atropine s. c. pro toto and 10.0 mg trimedoxim per kg 1. w. i. v. In both cases of poisoning with doses = LD50 in i. m. administration, the mentioned system was actually positive. In a single administration irrespective of the doses of the used drugs, the system does not guarantee survival after ingestion of anticholinesterasic doses above LD50.

A single application of a mixture of cholinolytic and reactivator of cholinesterase (TMB-4 compos. SPOFA) administered intravenously in the dose of 10.0 mg of trimedoxim per kg of live weight to sheep for 60 minutes after an intramuscular intoxication with O-ethyl S-(2-dimethylaminoethyl) methyl phosphonothioate (EDMM) in the dose of 0.00835 mg per kg of live weight (i.m. LD50, 2h) produces an immediate clinical effect. The reactivation of the erythrocytary acetyl cholinesterase (AChE, E.C.3.1.1.7.) examined in 15 minutes after the administration of the antidotal mixture is almost 100 p.c., the reactivation of the plasmatic butyryl cholin esterase (ChE, E.C.3.1.1.8.) approx. from 70 to 80 p. c. Restitution ad integrum occurred not later than in 14 days after the intoxication.