[To test or not to test--that is the question: no definite indication for testing in our opinion].
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Biomedical subjects
Publications and source records attributed to M Svoboda.
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The effects of Gila monster venom on dispersed rat pancreatic acini were compared with those of secretin and VIP. The efficacy of the venom in terms of amylase release was much higher (a 24-fold increase over basal secretion) than that of secretin (a 4-fold increase) and VIP (+ 40% only). On the other hand, cyclic AMP levels increased 12-fold with the venom, as compared to 18-fold with secretin and 16-fold with VIP. The venom, VIP and secretin all displaced 125I-VIP and the competition curve with the venom was steeper, suggesting that all VIP-recognizing receptors bound the venom with the same affinity. VIP receptors were, however, not responsible for the release of amylase provoked by the venom since VIP (and secretin) did not inhibit the secretory action of the venom. The venom exerted no effect on 45Ca efflux and its secretory effect did not depend on the presence of external calcium. Besides, the effect of CCK-8 on amylase release was additive with the effect of the venom. A first exposure to the venom induced a refractoriness to itself with respect to amylase release but not in terms of cyclic AMP increase. In conclusion, Gila monster venom may contain one component binding to VIP/secretin receptors with resulting cyclic AMP elevation. A second venom component may be responsible for the high secretory efficacy, without involving cyclic AMP or calcium efflux.
A fast analytical approach for the simultaneous quantitative screening for illicit drugs in serum and urine without tedious chromatographic separation steps was developed by combining solid-phase extraction (SPE) followed by flow-injection analysis (FIA) with ionspray-ionization and tandem mass spectrometry (MS-MS) detection using a PE Sciex API 300 triple-quadrupole MS. MS-MS analysis was performed by sequentially isolating the precursor ions of the analytes and their deuterated standards with subsequent fragmentation and monitoring of one fragment ion for each substance. A multiple-reaction monitoring experiment was set up for morphine (MO), codeine (COD), amphetamine (AMP), benzoylecgonine (BZE), and their deuterated analogues. For method evaluation, serum samples spiked with 2-1000 ng of each drug and deuterated standards were extracted by mixed-mode SPE, redissolved in CH3CN-NH4OAc-buffer, and directly injected by flow injection into the ionspray source. The specificity of this new method was demonstrated by testing compounds with similar chemical structure for interferences from the analytes of interest (e.g., dihydromorphone, morphine glucuronide, and 6-monoacetylmorphine with MO; dihydrocodeine and hydrocodone with COD; cocaine [COC] and ecgonine methylester with BZE; methamphetamine with AMP). The possibility of interferences of such compounds with the FIA-ionspray-MS-MS screening method is discussed. Spiked serum samples and serum and urine samples from drug addicts and victims of drug abuse were analyzed with FIA-MS-MS and, after derivatization, with gas chromatography-mass spectrometry (GC-MS). Comparable quantitative results were obtained with both methods; no interferences with metabolites or other compounds were found. The FIA-ionspray-MS-MS method is a fast, quantitative, sensitive, and highly specific alternative method to drug-screening by immunoassays, high-performance liquid chromatography, and GC-MS. It can be used for the simultaneous detection of different drugs and metabolites such as opiates, COC, AMP derivatives, and many other drugs.
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The article includes a review of literature and own studies about hypnosis considered from the point of view of the subject's alertness or non-alertness, his activity or passivity in the hypnotic state. Activity is considered as a construct describing behavioral and experiential dynamics. This includes the general reactivity and the level of spontaneousness and initiative. The author's studies refer to the influence of hypnotic behavior on the dimension alert-non alert. The following factors were found to be important subject's preconception of hypnosis, the kind of hypnotic procedure used, subject's hypnotic susceptibility, subject's personality traits, implicite demand characteristics of particular suggestions, specific explicit suggestions and subject's training.