Enantioseparation and a comprehensive spectroscopic analysis of novel synthetic cathinones laterally substituted with a trifluoromethyl group.

Recently, the number of structural modifications of synthetic cathinones has been growing making them the second largest group of new psychoactive substances in Europe. Although they are abused because of their various psychoactive effects, some compounds from this group also serve as pharmaceuticals. Since synthetic cathinones are chiral molecules with one chiral center, their biological, toxicological, and pharmacological properties may significantly differ according to their absolute configuration and enantiomeric excess. In this study, we have synthesized two substances bearing a pharmacologically interesting trifluoromethyl group and developed a chiral liquid chromatography method using a polysaccharide chiral stationary phase to separate the corresponding enantiomers of both these drugs. Subsequently, we utilized molecular spectroscopic methods including chiroptical (electronic circular dichroism and vibrational circular dichroism) and non-polarizable (infrared and ultraviolet absorption) spectroscopies. In combination with density functional theory calculations, we have obtained stable conformers of selected enantiomers in solution and their relative abundances, which we used to simulate their spectra. The experimental and calculated data have been used to elucidate the 3D structure of the enantiomerically pure compounds and assign the absolute configuration of all prepared compounds.

Indazole-derived synthetic cannabinoids: Absolute configuration determination and structure characterization by circular dichroism and DFT calculations.

An increasing number of products containing synthetic cannabinoids pose a growing crisis to public health worldwide. Recently, a rising number of cases of serious adverse health effects, intoxications, and death cases associated with synthetic cannabinoids were reported. The current study represents the comprehensive structural analysis of three new synthetic cannabinoids (AB-, ADB- and AMB-FUBINACA) in solution investigated by electronic and vibrational circular dichroism together with the conventional methods of infrared and ultraviolet absorption spectroscopy, all supported by the density functional theory (DFT) calculations. The best level of theory to reproduce the experimental wavenumbers and wavelengths was found to be the B3PW91 method with a 6-311++G(d,p) basis set including the implicit solvent effect simulation. Very good agreement between the experimental and simulated spectra allowed us to determine the absolute configuration and a detailed interpretation of the IR absorption, VCD, ECD and UV spectra of AB-, ADB- and AMB-FUBINACA. In addition, the HOMO and LUMO electronic transitions were calculated.

A single inhalation of vapor from dried toad secretion containing 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) in a naturalistic setting is related to sustained enhancement of satisfaction with life, mindfulness-related capacities, and a decrement of psychopathological symptoms.

BACKGROUND: 5-methoxy-N,N-dimethyltryptamine (hereinafter referred to as 5-MeO-DMT) is a psychedelic substance found in the secretion from the parotoid glands of the Bufo alvarius toad. Inhalation of vapor from toad secretion containing 5-MeO-DMT has become popular in naturalistic settings as a treatment of mental health problems or as a means for spiritual exploration. However, knowledge of the effects of 5-MeO-DMT in humans is limited. AIMS: The first objective of this study was to assess sub-acute and long-term effects of inhaling vapor from dried toad secretion containing 5-MeO-DMT on affect and cognition. The second objective was to assess whether any changes were associated with the psychedelic experience. METHODS: Assessments at baseline, within 24 h and 4 weeks following intake, were made in 42 individuals who inhaled vapor from dried toad secretion at several European locations. RESULTS: Relative to baseline, ratings of satisfaction with life and convergent thinking significantly increased right after intake and were maintained at follow-up 4 weeks later. Ratings of mindfulness also increased over time and reached statistical significance at 4 weeks. Ratings of depression, anxiety, and stress decreased after the session, and reached significance at 4 weeks. Participants that experienced high levels of ego dissolution or oceanic boundlessness during the session displayed higher ratings of satisfaction with life and lower ratings of depression and stress. CONCLUSION: A single inhalation of vapor from dried toad secretion containing 5-MeO-DMT produces sub-acute and long-term changes in affect and cognition in volunteers. These results warrant exploratory research into therapeutic applications of 5-MeO-DMT.

Individual prolactin reactivity modulates response of nucleus accumbens to erotic stimuli during acute cannabis intoxication: an fMRI pilot study.

RATIONALE: Self-report studies indicate that cannabis could increase sexual desire in some users. We hypothesized that intoxication increases activation of brain areas responsive to visual erotica, which could be useful in the treatment of hypoactive sexual desire disorder, a condition marked by a lack of sexual desire. OBJECTIVES: The aim of this study is to assess the aphrodisiacal properties of cannabis. METHODS: We conducted an open-randomized study with 21 heterosexual casual cannabis users. A 3T MRI was used to measure brain activation in response to erotic pictures. Blood samples were collected to determine the serum levels of cannabinoids, cortisol and prolactin. Participants were grouped according to whether they had ever experienced any aphrodisiacal effects during intoxication (Group A) or not (Group non-A). RESULTS: Intoxication was found to significantly increase activation in the right nucleus accumbens in the Group A while significantly decreasing activation in the Group non-A. There was also a significant interaction between the group and intoxication, with elevated prolactin in the Group non-A during intoxication. No intoxication-related differences in subjective picture evaluations were found. CONCLUSION: Cannabis intoxication increases activation of the right nucleus accumbens to erotic stimuli. This effect is limited to users whose prolactin is not elevated in response to intoxication. This effect may be useful in the treatment of low sexual desire.

Immediate revision in patients with bilateral recurrent laryngeal nerve palsy after thyroid and parathyroid surgery. How worthy is it?

The aim of the present study was to determine whether immediate revision surgery has benefits for patients with iatrogenic bilateral recurrent laryngeal nerve (RLN) palsy. From January 1, 2004 to January 30, 2011, 29 consecutive patients underwent immediate revision after total thyroidectomy. The cohort comprised 29 patients, 2 males and 27 females, aged 23 to 76 years (median 52 years). Identification of the type and extent of injury of each branch was reported in the protocol, and reconstruction was performed whenever possible. A complete transection of the nerve or one of its branches was found in 14 and 5 nerves, respectively. In three patients, the nerve was completely or partially transected on both sides. Seven anatomically intact nerves were injured by loaded ligature, in one case there was a sign of thermal damage and four nerves showed signs of excessive manipulation (thinning of the nerve trunk). Primary end-to-end anastomosis was performed in seven completely transected RLN and four transected anterior branches of RLN. None of the reconstructed nerve trunks or its branches regained function, although good muscle tone was observed. 23 of 38 intact nerves (61%) regained function, and normal vocalcord mobility on both sides was restored in only four patients. In all cases with regained vocal-cord mobility, functional recovery occurred within 3 months after primary surgery. In conclusion, immediate revision after thyroidectomy may help to indicate the type of RLN damage, which is a predictor of functional recovery and one of major factors influencing future therapeutic management.

The influence of leukotriene receptors' antagonists on experimentally induced ulcer in rats.

AIM: Gastric mucosal cells synthesize a large number of eicosanoids (including leukotrienes) which are distinctively involved in ulcerogenesis. This experimental study investigated the effect of 4 leukotriene receptors' antagonists on indomethacin(IND)-induced ulcer in rats. MATERIAL AND METHODS: Animals were divided into six groups (of 8 rats each) which received as follows: group I (control)--saline; group II--IND 20 mg/kg p.o.; group III--montelukast sodium 10 mg/kg p.o. and IND 20 mg/kg p.o.; group IV-- a quinolinic derivative (19363) 20 rM/kg p.o. and IND 20 mg/kg p.o.; group V--a phenethylamido derivative (20599) 20 microM/kg p.o. and IND 20 mg/ kg p.o.; group VI--a resatophenone derivative (19072) 20 microM/kg p.o. and IND 20 mg/kg p.o. Animals were sacrificed eight hours after the last administration. The gastric index (UI), gastric pH and histopathological exam were performed on the removed stomachs. RESULTS: UI was 25.8 +/- 6.3 in group II, 10.20 +/- 2.3 in group III (p < 0.05), 21.60 +/- 2.8 in group IV, 13.40 +/- 2.4 in group V (p < 0.05) and 20.80 +/- 3.9 in group VI. pH values were 2.2 +/- 0.3 in group II, 3.4 +/- 0.9 in group III (p < 0.05), 2.6 +/- 0.8 in group IV, 2.9 +/- 0.7 in group V and 2.5 +/- 0.6 in group VI. The histopathological exam revealed: (i) typical lesions for ulcer in groups II, IV and VI, the most severe being in group II; (ii) only superficial non-hemorrhagic erosions in group V; (iii) small erosion areas alternating with large zones of normal mucosa in group III. The obtained data demonstrated different degrees of gastro-protective activity for the studied leukotriene receptor antagonists. CONCLUSION: Especially montelukast but also phenethylamido derivative (20599) exhibited a partial gastro-protective effect on IND-induced ulcer in rats.

Magnetic resonance imaging of the rat brain after epileptic seizures--preliminary results.

The magnetic resonance imaging (MRI) of the rat brain after the epilepsy seizures has been performed. As a first step, the model of the kainic acid (KA) induced seizures has been conducted to examine the possibilities of magnetic resonance imaging system kept in disposition. Seven Wistar albino rats, weighing about 300 g, were used in this study. We administered six of them with intraperitoneal injection of 10 mg/kg of KA. The control animal received corresponding volume of the saline. Every animal was examined under systemic anaesthesia induced by an intraperitoneal injection of thiopental sodium approximately 15 minutes before scanning. Diffusion-weighted imaging (DWI) has been used to acquire the coronary scans of the rat brain. The progress of hyper intense signal at the cerebral cortex and amygdale has been observed. Marked asymmetry of the signal intensity between hemispheres has been discovered. Subsequently the experimental model of audiogenic epilepsy will be conducted.

Results of peripheral nerve reconstruction by autograft.

OBJECTIVES: This paper presents the results achieved in microtechnique surgeries performed during a 15-year-long period (1985-1999). By performing surgeries on 60 patients, 63 nerves were treated. MATERIAL AND METHODS: In 42 patients with injuries of peripheral nerves of upper extremities, 45 nerves were reconstructed by autografts. 14 patients were subjected to reconstructive surgeries on peripheral nerves of lower extremities. In 4 patients we reconstructed the facial nerve by means of autograft. The analysis of surgical effects has been made in dependence on indicators as follows: period elapsed from injury to surgery, age of patient, nature of injury, length of autograft, location of injury, kind of nerve inflicted. RESULTS: When assessing the results of reconstructive surgeries of peripheral nerves of lower and upper extremities we observed a big difference on the behalf of upper extremities. High efficiency can be seen in tibial nerve surgeries of lower extremities. In general we achieved good results in facial nerve reconstructions. CONCLUSION: The crucial factor that has an impact on the result of surgery is that of the time which elapsed from injury to reconstructive surgery. The factor is especially marked in younger patients. (Tab. 7, Ref. 15.).

New insights on disintegrin-receptor interactions: eristostatin and melanoma cells.

Viper venom disintegrins have been used frequently to study the cellular receptors which characterize various types of cells, including platelets, endothelial cells and cancer cells. While the majority of such analyses have pointed to involvement of integrin receptors alphavbeta3, alpha5beta1 or alphaIIbbeta3, this may not always be so. Eristostatin, from Eristocophis macmahoni, is a potent inhibitor of ADP-induced platelet aggregation as well as of human and murine melanoma metastases in mouse model systems. This disintegrin requires an RGDW motif, as well as an intact C-terminus, in order to interact with both platelets and four different types of melanoma cells. Eristostatin causes nonmetastatic SBc12 melanoma cells to show higher susceptibility to specific killing by NK-like TALL-104 cells. While it is known that eristostatin binds to alphaIIbbeta3 on platelets, the receptor with which eristostatin binds to the melanoma cells has not yet been identified.

Surgical treatment of injuries of nervus fibularis.

STARTING POINT: In this retrospective study, we present the results of 40 surgeries of 40 patients that within the period of 15 years, i.e. from 1985 to 1999 were provided the treatment of 40 lesions of n. fibularis, historically treated as problematic in terms of successful healing. The work provides the fundamental lines of their surgery treatment. MATERIAL AND METHODS: From the total number of 40, external neurolysis was performed to 20 patients. The remaining 20 patients were provided with reconstruction surgeries of the injured nerves, while 8 surgeries was done by suture of peripheral nerve and 12 surgeries were performed by nerve graft, in cases of complete and persisting neurological deficit and absence of action potential at EMG. The mechanism of lesion included the damages of nerve from elongation, with or without fracture, "sharp" or "blunt" lesions, lesions of shooting, compressions and iatrogenic injuries. If the spontaneous adjustment did not occur within the period of 2-6 months after the lesion, the patients underwent surgery. We performed the analysis of the efficiency of the surgical intervention depending on the following parameters: period of surgery from the lesion, patient's age, nature of lesion, degree of lesion, type of surgery intervention. RESULTS: With 27 of 40 an effective adjustment was achieved preventing the sagging of the foot trace and with 25 of 40 protective sensitivity appeared. After neurolysis with 18 of 20 patients (90%) we achieved effective degree of adjustment in spite of heavy pre-surgical motor deficit. With 8 patients an "end to end" suture was performed and with 6 (75%) the degree of adjustment was 3 or higher. 12 patients requested reconstruction surgeries with the help of nerve grafts, the length of grafts varied from 4 to 20 cm. The grafts were shorter than 5 cm with 2 patients, 1 with cut lesion and 1 patient with iatrogenic lesion. With both patients the function was adjusted to the degree M4. With 1 of 4 patients (25%) with the graft of 6 to 12 cm and with none of 6 with the grafts from 13 to 20 cm the adjustment of the degree 3 or higher was not achieved. In this cases, however, we noticed partial adjustment of trophic and tonus, however at the absence of motor adjustment. CONCLUSION: The pre-surgical and persurgical examinations are indispensable conditions for obtaining optimal results. It is worth of mentioning that surgical treatment proximal lesins of n. fibularis yielded better results than treatment of more distal lesions in the area of knee. (Tab. 5, Ref. 20.)

Stereoselective pharmacokinetics of flobufen in rats.

Stereoselectivity of the pharmacokinetics of the nonsteroidal anti-inflammatory drug flobufen, 4-(2', 4'-difluorobiphenyl-4-yl)-2-methyl-4-oxobutanoic acid, was studied in male Wistar rats after intravenous administration. Pharmacokinetic parameters and chiral inversion of flobufen enantiomers were studied after a bolus injection of the racemate and individual enantiomers (5 mg/kg). Determinations of the enantiomers in rat plasma were performed using chiral HPLC (terguride column). After i.v. administration of flobufen racemate, plasma levels of R-enantiomer decreased more rapidly. The S-/R-enantiomer ratio of AUCs after rac-flobufen was 13.3. The total plasma clearance value of S-flobufen was more than 10-fold lower than R-flobufen. The other pharmacokinetic parameters of the enantiomers were also significantly different. While only traces of R-enantiomer (less than 1%) were detected in rat plasma after S-flobufen administration, considerable conversion to the S-enantiomer was found after injection of R-flobufen (R-enantiomer AUC/S-enantiomer AUC = 0.52). The results indicate substantial stereoselectivity in the disposition of flobufen enantiomers in the rat, which is, at least in part, attributed to chiral bioconversion.

Metabolic pathways of flobufen-a new antirheumatic and antiarthritic drug. Interspecies comparison.

Metabolic transformations of flobufen, [4-(2',4'-difluoro-biphenyl-4-y1)-4-oxo-2-methylbutanoic acid], a non-steroid antiinflammatory agent, were studied in vitro using the following biological models and species: rat and mouse liver homogenates and liver subcellular fractions (5 000 g and 100 000 g supernatant, mitochondria); rat, mouse, rabbit, guinea-pig and mini-pig liver microsomes; isolated rat hepatocytes; perfused rat liver and 5000 g rat muscle tissue supernatant. Reduced flobufen [4-(2',4'-difluorobiphenyl-4-yl)-4-hydroxy-2-methylbutanoic acid] is the major metabolite generated by the subcellular fractions (in the mild acidic extraction conditions during subsequent laboratory processing is converted to its lactone form). It was detected upon the incubation of flobufen with liver microsomes isolated from all the animals tested. Maximum yield of reduced flobufen in experiments with rat and mouse liver microsomes was found after anaerobic incubation with NADPH. This finding combined with the knowledge of subcellular distribution of enzymes suggest that metabolite formation depends on the activity of microsomal reductases and, probably, also on the activity of the important microsomal reductase, cytochrome P-450. Another flobufen metabolite, arylacetic acid [(2',4'-difluorobiphenyl-4-yl)ethanoic acid], is generated from the reduced metabolite by the cleavage of its side chain, and was detected in isolated hepatocytes - it was the only metabolite found in urine and faeces upon oral administration of the drug. All these metabolites were identified and quantified.

[Substituted benzo[b]thiophenes with anti-leukotriene activity]. / Substituované benzo[b]thiofeny s antileukotrienovou aktivitou.

The cyclizing reaction of cinnamic acid (Ia) with thionyl chloride was optimized and a series of 3-chloro-6-subst.benzo[b]thiophene-2-carbonyl chlorides Va-Vn was prepared. Chloride Va was transformed into a series of N-aryl-3-subst. (Cl, OCH3, OH) benzo[b]thiophene-2-carboxamides VII, IX, X. The drugs were subjected to an evaluation of selected antileucotriene activities in vitro and of the anti-inflammatory effect in vivo. In agreement with the assumed mechanism, inhibition of the ear inflammation is conditioned by the antileucotriene activity, whereas inhibition of the carrageen oedema is not due to this mechanism alone.

[The present status of research and development of original drugs]. / Soucasný stav výzkumu a vývoje originálních léciv.

The objective of the article is to make readers familiar with contemporary methods of research and development of original drugs and elucidate economic aspects of pharmaceutical research. The contemporary strategy of research and development in the Research Institute for Pharmacy and Biochemistry is discussed in relation to general trends. Pharmaceutical research and development are characterized by high costs which vary in the majority of pharmaceutical companies engaged in the development of new drugs between 12-16% of the total turnover. The author discusses problems associated with the return rate of these investments in conjunction with patent protection and the time taken to develop original drugs. Expedient use of the large financial funds calls for rational management of research and development. The author therefore pays attention to an analysis of rational methods of management of research and development which are applied in the selection of a research programme and of research projects, to modern methods of research and to the organization of research and development. The author deals subsequently in more detail with contemporary methods of research focused on the detection of leading structures, where molecular modelling and technology of combinatorial chemistry are used. By their combination with optimization procedures using statistical data analysis rational design of molecules is made possible.

Pharmacological profile of the novel potent antirheumatic 4-(2',4'-difluorobiphenyl-4-yl)-2-methyl-4-oxobutanoic acid.

On the basis of basic screening for novel, more potent antiarthritics VUFB-16066 (4-(2',4'-difluorobiphenyl-4-yl)-2-methyl-4-oxobutanoic acid, CAS 112344-S2-2) was chosen as a compound with pronounced anti-inflammatory and immunomodulatory effects, with good gastric tolerance and relatively low toxicity. VUFB-16066 is a dual cyclooxygenase and 5-lipoxygenase inhibitor, and it suppresses alloantigen-driven cellular immune response and phagocytosis of stimulated peritoneal cells. VUFB-16066 exhibits prolonged pharmacological activity connected with its major metabolite having a very long half-life. In the model of adjuvant arthritis VUFB-16066 improves most of disease symptoms including immunopathological disturbances, which indicates possible disease-modifying activity of the drug. The beneficial antiarthritic effect of VUFB-16066 has been also confirmed in patients with rheumatoid arthritis.

Changes of motor evoked potential amplitudes following magnetic stimulation after hyperventilation.

The influence of hyperventilation on amplitudes of motor evoked potentials (MEP) following cortical and root magnetic stimulations was tested in ten healthy volunteers. Hyperventilation significantly increased MEP amplitude following cortical stimulation (p < 0.01) but failed to change MEP amplitude following root stimulation. This finding is compatible with the concept of hyperventilation as a promoter of greater excitability at the level of cortical structures. The provoking method applied during magnetic cortical stimulation might be a useful procedure in studying some functional affections associated with hyperventilation, such as hyperventilation tetany or panic disorder.

[Strategies for pharmaceutical research and development. II. Generic drugs]. / Strategie farmaceutického výzkumu a vývoje. II. Generická léciva.

When the patent protection is terminated, the original registered-mark preparation becomes a generic drug, which results in a decrease in its price as compared with the original pharmaceutical. The effects of changes in price relation are discussed from the viewpoint of the generic firms and the manufacturers of original preparations. The differences in the insurance system and legislative regulations of the registration of generic preparations can markedly the size influence of the share of generic drugs in the total consumption of drugs. The future development of generic drugs from a general viewpoint is discussed in relation to the contemporary extensive expiration of patent protection of drugs. The hitherto results are summed up and the topics for the present strategy of the development of generic drugs in the Research Institute for Pharmacy and Biochemistry, or in the Czech Republic, respectively are discussed.

[The strategy for pharmaceutical research and development. I. Original drugs]. / Strategie farmaceutického výzkumu a vývoje. I. Originální léciva.

Pharmaceutical research and development are characterized by high costs, which in the countries with developed pharmaceutical industry range from 12 to 16% of the total turnover. Purposeful use of considerable financial resources requires rational management of research and development. The principal criteria of rational research can be stated as follows: (a) profitable measure of risk, (b) strategy of research and development, (c) use of financial resources, (d) organization and methods of research. These aspects of rational management are discussed and the prospects and limits of this research in the Czech Republic in relation to general regularities are formulated. Attention is paid to the Research Institute for Pharmacy and Biochemistry which has obtained the position of the only institute for comprehensive research and development of human medicaments in the country. The hitherto results are summed up and the contemporary strategy of research and development in the Institute is discussed.

Late responses after transcranial magnetic stimulation in stroke.

In addition to early responses after transcranial magnetic stimulation, usually designated as Motor Evoked Potentials (MEP), several late responses have been reported in intervals up to 500 ms following stimulus. Our attention in this work was focused on the response in interval 150-300 ms after stimulus output, which is also designated as S > 150 response. We monitored longitudinally late S > 150 response in group of 19 stroke patient with verified hemispherical ischemic lesion. Our results have shown that the presence of late S > 150 response on the first day after stroke predicts an excellent improvement of clinical deficit and that late S > 150 response is more sensitive to hemispheric lesion than early MEPs. From this point of view, recording of late responses can supplement early MEP recording. Our study demonstrated that supratentorial structures are involved in the origin of the S > 150 response. According to the observation that in some patients a normal early response was present and an S > 150 response was absent on the hemiparetic side, and both responses were present on the unaffected side, we hypothesize that cortical structures play an important role in S > 150 response.