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In a dense plasma environment, the energy levels of an ion shift relative to the isolated ion values. This shift is reflected in the optical spectrum of the plasma and can be measured in, for example, emission experiments. In this work we use a recently developed method of modeling electronic states in warm dense matter to predict these level energies. In this model excited state energies are calculated directly by enforcing constrained one-electron occupation factors, thus allowing the calculation of specific transition and ionization energies. This model includes plasma effects self-consistently, so the effect of continuum lowering is included in an ab initio sense. We use the model to calculate the K-edge and K-alpha energies of solid density magnesium, aluminum, and silicon over a range of temperatures, finding close agreement with experimental results. We also calculate the ionization potential depression to compare to widely used models and investigate the effects of temperature on the lowering of the continuum.

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Accurate modeling of warm and hot dense matter is challenging in part due to the multitude of excited states that must be considered. Here, we present a variational framework that models these excited states. In this framework an excited state is defined by a set of effective one-electron occupation factors, and the corresponding energy is defined by the effective one-body energy with an exchange and correlation term. The variational framework is applied to an atom-in-plasma model (a generalization of the so-called average atom model). Comparisons with a density functional theory based average atom model generally reveal good agreement in the calculated pressure, but our model also gives access to the excitation energies and charge state distributions.

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An earlier proposed approach to molecular response functions based on the intermediate state representation (ISR) of polarization propagator and algebraic-diagrammatic construction (ADC) approximations is for the first time employed for calculations of nonlinear response properties. The two-photon absorption (TPA) spectra are considered. The hierarchy of the first- and second-order ADC∕ISR computational schemes, ADC(1), ADC(2), ADC(2)-x, and ADC(3/2), is tested in applications to H(2)O, HF, and C(2)H(4) (ethylene). The calculated TPA spectra are compared with the results of coupled cluster (CC) models and time-dependent density-functional theory (TDDFT) calculations, using the results of the CC3 model as benchmarks. As a more realistic example, the TPA spectrum of C(8)H(10) (octatetraene) is calculated using the ADC(2)-x and ADC(2) methods. The results are compared with the results of TDDFT method and earlier calculations, as well as to the available experimental data. A prominent feature of octatetraene and other polyene molecules is the existence of low-lying excited states with increased double excitation character. We demonstrate that the two-photon absorption involving such states can be adequately studied using the ADC(2)-x scheme, explicitly accounting for interaction of doubly excited configurations. Observed peaks in the experimental TPA spectrum of octatetraene are assigned based on our calculations.

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The biotransformation of dimethindene (CAS 5636-83-9, dimethindene maleate, CAS 3614-69-5) after oral administration was determined in urine using an HPLC gradient method. Besides the phase I metabolites the conjugates of the hydroxylated metabolites with glucuronic and/or sulfuric acid were quantitatively determined after enzymatic deconjugation. The cumulative excretion of 6-hydroxydimethindene and 6-hydroxy-N-demethyldimethindene in human urine after hydrolysis of the conjugates ranged from 18 to 23% of the administered dose, independent of the amount of the dose applied. The results indicate that conjugated 6-hydroxydimethindene is the main metabolite of dimethindene. Increasing doses of 5 to 20 mg dimethindene maleate did not affect the relative amount of the excreted metabolites but changed the ratio of 6-hydroxydimethindene to 6-hydroxy-N-demethyldimethindene from 3:1 to 1:1. In rats about 4 to 8% of the administered dose of dimethindene was excreted as dimethindene-N-oxide which is the main metabolite in rat urine. After administration of R-(-)-dimethindene the elimination of all metabolites was 2 to 3 fold higher compared to the administration of the S-(+)-enantiomer. By chiral HPLC, in 10 human volunteers a stereoselective elimination of N-demethyl-dimethindene after oral administration of racemic dimethindene with the predominant excretion of the R-(-)-enantiomer was observed.

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The effects of dimethindene maleate (CAS 3614-69-5) on the central nervous system-as sustained release pellets (Fenistil OAD; OAD = once a day) and sustained release tablets (Fenistil retard) with an immediate release fraction-were investigated by means of the oculodynamic test (ODT) and visual analogue scales and compared to loratadine (CAS 79794-75-5) and placebo. In the confirmatory part of the study 18 healthy volunteers were included in a single-blind, randomised, 3-way change-over design with Fenistil OAD, loratadine, and placebo. An additional, fourth exploratory arm with Fenistil retard was run in 6 (out of the 18) subjects after completing the main part of the study. The ODT includes electro-oculography, choice reaction task, and cardiologic parameters under workload. Visual analogue scales were used for subjective ratings on well-being and drug effects concerning wakefulness (sedation), excitation, dizziness, performance, effort, and dry mouth. The results show no relevant differences between either of the active drugs and placebo. Therefore it can be stated that after a single dose there is no sedating effect of dimethindene maleate compared to loratadine or placebo.

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Twelve asymptomatic subjects (4 female, 8 male), being allergic to grass pollen proved by positive anamnesis, positive Prick-test and positive nasal provocation test, were challenged under controlled conditions with purified airborne grass pollen of Dactylis glomerata in the Vienna Challenge Chamber (VCC), located at the Universitätsklinik für Hals-Nasen-Ohrenheilkunde, Allgemeines Krankenhaus (AKH), der Stadt Wien, Vienna (Austria) by means of a double-blind, randomised, cross-over design, with 2 weeks wash-out periods between. Efficacy and safety of 2 concentrations of dimethindene (dimethindene maleate; DMM, CAS 3614-69-5, Fenistil resp. Foristal) 0.025% DMM, 0.1% DMM) were tested vs placebo as negative control and vs 0.1% azelastine as positive control, as topical nasal sprays. The tested nasal sprays were applied as single doses in the morning (2 puffs = 0.28 ml of the respective solution) to each nostril 15 min before the start of the 4 h lasting provocation procedure in the VCC, thus representing a total daily dose of 0.14 mg resp. 0.56 mg DMM and 0.56 mg azelastine, respectively. Compared to placebo, the objective variables nasal flow (150 Pa., measured by active anterior rhinomanometry) and nasal secretion (g), showed similar onset of antiobstructive and antisecretory effects in the nose after 0.1% DMM and 0.1% azelastine, respectively. The same applied for the subjective nasal symptom complex and for nasal symptom scores, evaluated by Visual Analog Scale (VAS): Time curves showed statistically significant and clinically relevant superiority of 0.1% DMM and 0.1% azelastine vs placebo, during the 4 h lasting provocation period. 0.025% DMM was not significantly different from placebo. No systemic adverse events were reported after the 4 tested preparations. Only a total of 3 subjects reported very slight local irritations (1 subject after placebo, 1 subject after 0.025% DMM and 1 subject after 0.1% azelastine). However, after 0.1% DMM no local adverse events were reported. It is concluded from this study that 0.1% DMM as nasal spray, is an efficient and safe galenical formulation for nasal spray application for patients suffering from seasonal allergic rhinitis (SAR).

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The aim of this study was to investigate, if the the combined treatment of compression stockings and drug treatment with oxerutins (O-(beta-hydroxyethyl)-rutosides, Venoruton) provides additional benefit for patients with chronic venous insufficiency (CVI) compared to compression treatment alone. Oxerutins belong to the group of oedema protective agents and possess anti-exudative and membrane protective activity. A total of 133 female patients with CVI grade II participated in this double-blind, randomised, multi-centre, parallel-group study with two treatment groups. The whole study lasted for 19 weeks, and consisted of a one week placebo run-in phase, 12 weeks treatment phase, followed by a 6 weeks treatment-free follow-up period. All patients received a basis compression therapy that consisted of standard compression stockings. In order to standardise initial fitting of stockings in this multi-centre setting, stockings were fitted after one week of standard diuretics starting at baseline and then stockings were worn for the following 11 weeks. Patients were randomised to receive oxerutins (2 x 500 mg daily) or matching placebo. Leg volumes (water displacement) and associated subjective symptoms (visula analogue scale) were measured during a placebo run-in period at enrolment (week - 1) and half a week later (week - 1/2), at baseline week 0), at 4, 8, 12 weeks on treatment, and again after a 3- and 6-weeks treatment-free follow-up. The primary efficacy criterion, the area under the baseline from week 0 to week 18 (AUB0-18) of leg volume changes, as measurement of the global change of leg oedema during the study, resulted in a superior reduction of -5589 ml.d for the combined treatment with oxerutins compared to -2101 ml.d for placebo (p = 0.012). The mean change of leg volume compared to baseline after 12 weeks of treatment was -63.9 ml for stockings and oxerutins, and -32.9 ml for the patients who received stockings and placebo (p < 0.05). Oxerutins showed a prolonged effect in the follow-up phase compared to placebo, with mean AUB values for week 12 to week 18 of -1769 ml.d versus -133 ml.d (p < 0.01). The study demonstrated that the combined therapy of compression stockings and drug treatment with oxerutins is significantly superior in reducing leg oedema resulting from chronic venous insufficiency compared to compression treatment alone.

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Oxerutins (O-(beta-hydroxyethyl)rutosides, HR, Venoruton) and horse chestnut extract (HCE) are active principles of first priority for the pharmacological treatment of chronic venous insufficiency (CVI). The efficacies of both compounds were shown in numerous, double-blind, randomized, placebo controlled clinical trials. Besides the direct comparison of the two compounds the aim of the study was to investigate the initial dose/maintenance dose concept for HR. 137 female, postmenopausal patients with CVI II finished the study according to protocol. Following one week placebo run-in the patients were treated either with 1000 mg/d HR, 600 mg/d HCE or 1000 mg/d for 4 weeks and than with 500 mg/d HR within the initial dose/maintainance dose concept for 12 weeks and observed for further 6 weeks. A main confirmative criterion was the volume reduction of the leg. Subjective criteria were descriptively evaluated. HR (1000 mg/d) was proven to be equivalent or better, reducing the leg volume (AUB0-18) by -5273 +/- 11418 ml.d compared to -3187 +/- 10842 ml.d under HR (1000 mg/d and 500 mg/d), and -3004 +/- 7429 ml.d under HCE-treatment. Both compounds exhibit a substantial carry-over effect. The maintenance posology of HR is able to stabilize the therapeutic obtained under initial dose conditions.

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Oxerutins (O-(beta-hydroxyethyl)-rutosides, HR, Venoruton) are available in different releasing galenical formulations for the treatment of chronic venous insufficiency (CVI). In order to investigate the biopharmaceutical relevance of the releasing properties of the galenical forms the therapeutic efficacy between the commercially available forms was investigated (500 mg sustained release film tablets, 300 mg sustained release film tablets, 300 mg normally releasing capsules) in comparison to an aqueous solution and placebo. In total 100 female patients with CVI grade II participated. The study was carried out following a randomized, placebo controlled design with parallel treatment groups. Following a two-week run-in phase patients were treated for 12 weeks with different posologies of HR (2 x 1/d 500 mg, 3 x 1/d 300 mg, 1 x 1000 mg/d as aqueous solution). Main criterion was the reduction of leg volume following 12 weeks treatment. Subjective criteria were descriptively evaluated. All four HR treatments were significantly superior to placebo (p < 0.0008). The different posologies had no influence on the efficacy. The therapeutic efficacy is independent of the in vitro rate of release. The available forms are regarded as bioequivalent.

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The aim of the study was to develop a laboratory system to challenge mite allergic patients with physiological concentrations of Der p I in order to evaluate the efficacy of antiallergic drugs in mite allergic patients. A double-blind, placebo-controlled, cross-over study was designed with three consecutive sessions. Twelve patients with proven sensitivity to dust mite were treated with a single dose of dimethindene maleate in a FOAD formulation (4 and 8 mg vs. placebo) 12 h before a long-term challenge with mite allergen Der p I in the Vienna challenge chamber. Challenge was performed with a constant concentration of 40 ng Der p I per cubic meter of air for 4 h. Nasal parameters were recorded at 15 min intervals during long-term challenge. In comparison to placebo, dimethindene leads to a statistically significant reduction (p < 0.05) of the nasal response at both concentrations tested. The house-dust mite model in the Vienna challenge chamber thus proved to be a useful tool for drug investigations in mite allergies.

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Most antihistamines are assumed to possess a more or less pronounced sedative potential in addition to their antihistaminic properties. Therefore, a single-blind three-way crossover study was designed to assess the influence of single-dose dimethindene maleate (new "once a day formulation") on vigilance and performance vs. loratadine as reference and vs. placebo. Drug effects on performance were tested in 18 healthy volunteers by the oculodynamic test [ODT, i.e. choice reaction task (CRT), combined with recording of electrooculography (EOG) and cardiovascular parameters] and effects on subjective well-being by visual analogue scales (VAS). Main target parameters for evaluation of CNS-effects are latency and subjective perception of sedation (VAS). Neither statistically significant nor clinically relevant differences in all objective and subjective target variables (ODT and VAS) between active drugs and placebo, after single-dose administration were found. The same holds for accessory EOG, CRT and vital parameters under workload.

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The aim of the study was to evaluate the efficacy and duration of two doses of dimethindene, in a sustained release pellet formulation, with a standardized grass pollen provocation model (Vienna Challenge Chamber, VCC). The study of 12 grass pollen-allergic volunteers (verified by case history, skin prick test and RAST) was carried out in a placebo-controlled, double-blind, cross-over design. 12 h before a 4-hour continuous challenge with permanent 1,000 Dactylis grass pollen/m3 of air in the VCC, 4 or 8 mg of dimethindene (Fenistil pellets) or an identically appearing placebo was administered in three sessions. Nasal flow and resistance, nasal secretion and subjective symptoms were recorded at 15-min intervals during this long-term challenge under reproducible conditions. In comparison to placebo, dimethindene leads to a statistically significant reduction (p < 0.05) in nasal response and clinical symptoms for at least 16 h after treatment. The efficacy of 8 mg dimethindene was superior to that of 4 mg dimethindene; however, the differences between both active treatments were not statistically significant. Therefore 4 mg dimethindene once a day is adequate for usual pollinotic disease conditions.

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A sustained release form of dimetindene (dimethindene maleate, Fenistil, CAS 3614-69-5) was developed based on a micropellet technique. Aim of the study was to evaluate the efficacy and duration of two doses of dimetindene in a sustained release pellet formulation with a standardised grass pollen provacation model (Vienna Challenge Chamber; VCC). The study with 12 grass pollen allergic volunteers--verified by case history, skin prick test (SPT), and radio allergo sorbent test (RAST)--was carried out in a placebo controlled, double blind, cross-over design. 12 h before a 4-h-lasting continuous challenge with permanent 1000 dactylis grass pollen in the VCC, administration of dimetindene (Fenistil R Pellets) in doses of 4 mg, 8 mg or identically appearing placebo was scheduled in three sessions. Nasal flow and resistance, nasal secretion and subjective symptoms were recorded at 15-min intervals during this long-term challenge under reproducible conditions. In comparison to placebo, dimetindene leads to a statistically significant reduction (p < 0.05) of nasal response and clinical symptoms for at least 16 h after treatment. The efficacy of 8 mg dimetindene was pronounced over 4 mg, however, the differences between both active treatments were not statistically significant. Therefore 4 mg dimetindene once a day is the adequate treatment for usual pollinotic disease conditions.

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Oxerutins (Venoruton) and troxerutin (CAS 7085-55-4) are both mixtures of O-(beta-hydroxyethyl)-rutosides used for the treatment of chronic venous insufficiency. As di-O-(beta-hydroxyethyl)-rutosides and 7-mono-O-(beta-hydroxyethyl)-rutoside were found to be more active with regard to free radical scavenging compared to tri-O-(beta-hydroxyethyl)-rutoside the aim of this study was to compare oxerutins and troxerutin clinically. 12 female, post-menopausal patients with chronic venous insufficiency grade II participated in this double-blind study with random allocation to the treatment groups. They received 900 mg/day oxerutins or troxerutin for 12 weeks and were observed for 4 further weeks without treatment. Leg volumes (water displacement) and subjective symptoms (VAS, visual analogue scale) were evaluated before and following 2, 4, 8, 12 and 16 weeks. Both treatments were active in reducing leg volumes and in ameliorating subjective symptoms (mean volume reduction -167 +/- 157 ml x week). Volume reduction totalled to -261 +/- 154.2 ml x week for oxerutins and -73.2 +/- 97.1 ml x week for troxerutin. The difference is statistically significant (p = 0.04). The findings with subjective symptoms were in good accordance to the objective volume measurement. Oxerutins revealed a remarkable carry over effect.

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The aim of this study was to compare the efficacy of two posologies of hydroxyethylrutosides (HR) as maintenance dose for the reduction of leg oedema. The increase in leg volume induced by standing motionless for one hour was measured in 12 healthy young male volunteers by a highly sensitive water displacement method. The volume increase (approx. 87.8 units) was found to be very reproducible after a one-week placebo run-in period. The mean value after 3-weeks treatment at 1000 mg/day HR was reduced to 85.2 +/- 8.7 units. The subjects were then randomised to 3 groups and further measurements were made after additional 3, 5, 6 and 7 weeks. On placebo, the values returned to baseline within 5-6 weeks. On 500 mg/day, the values continued to oscillate around the values at randomisation (i.e., the effect was maintained). On continuing the dose unchanged at 1000 mg/day, the volume increases continued to fall progressively to 79.1 +/- 7.7 at the end of the further 7 weeks. After analysis of all mean volume changes relative to the values at time of randomisation, it was found that the 1000 mg/day dose showed a significant greater antioedematous effect than placebo (p = 0.0001) or 500 mg/day (p = 0.0028). Also the 500 mg/day dose was superior to placebo (p = 0.0328). We conclude that, after initial treatment for 3 weeks with 1000 mg/day, a dose of 500 mg/day is adequate to maintain the resultant anti-oedematous effect.(ABSTRACT TRUNCATED AT 250 WORDS)

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Dimetindene maleate (DMM, Fenistil, CAS 3614-69-5) a specific H1-receptor antagonist, is therapeutically used for the treatment of respiratory allergies, urticaria, itching dermatoses and generally pruritic sensations occurring with various diseases. As it exhibits local anaesthetic activity in the rabbit cornea and the local anaesthetic activity of a couple of H1-antagonists was found to be linearly correlated to the H1-potency represented by the pA2-values--and dimethindene maleate demonstrates a high pA2-value--it seemed worth investigating the local anaesthetic potency in man making use of an objective and well validated pain model, the Laser algesimetry. The study was carried out with 24 healthy volunteers in a double-blind placebo- and reference-controlled, randomized, cross-over design. Three different medications were applied with occlusive dressing: DMM, lidocaine, and placebo. Selective thermo-noxious stimulation of A-delta- and C-fibers was induced by a CO2-laser. Somato-sensory evoked vertex potentials (SEPs) were simultaneously recorded. Both verum treatments showed a remarkable analgesic potency compared to placebo. Effects were preferably concentrated on the peripheral N1-component of the SEPs. The overall means of the N1-amplitudes were suppressed compared to placebo by both active drugs, with the effects being more pronounced for DMM.

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Dimethindene, an antihistaminic drug, is the treatment of choice in dialysis patients suffering from skin itching. During hemodialysis procedures not only toxic metabolites, but also drugs are extracted from plasma. To answer the question if dimethindene is dialyzable from plasma, three healthy male volunteers received 4 mg of dimethindene solution intravenously. Ten minutes later 100 ml cubital vein blood was taken and 25,000 I.E. Liquemine was added. Plasma was separated and pumped through a cuprophan hollow fiber dialyzing module with an effective surface of 35 cm2. In periods of ten minutes samples of plasma and dialysate were taken to analyze their dimetindene concentrations. A mean clearance of 38 ml/min*m2, SD 10.2 and coefficient of variation [%] 26.8 was found. This is comparable to the well known clearance of theophylline, so it can be considered that dimethindene is eliminated from plasma during hemodialysis procedures.

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We have investigated the time-course of the flare inhibiting activity of dimethindene maleate in man and compared the resulting effect-kinetic data with those from pharmacokinetic investigations. The study was carried out in a double-blind, placebo-controlled cross-over design with randomly assigned healthy volunteers. Dimethindene maleate (4 mg) was orally applied, followed by intracutaneous histamine provocations (-1, 2, 5, 14, 17, 20, 23, 26, 29 h). The two cross-over periods were separated by a wash-out phase of 17 h. Flare areas were documented 5, 10, 20 and 30 min after provocation with histamine. A strong inhibition of the development of flares was observed. With regard to the time-course of the inhibiting effect, its maximum was observed at a provocation time of 5 h. The mean residence time of the inhibiting effect was calculated to be ca. 13 h. This is different from the mean residence time of ca. 8 h obtained from blood level data. Blood- and effect-levels are not linearly related under oral treatment conditions.

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O-(beta-hydroxyethyl)-rutosides (HR) is used for the treatment of disorders of the venous and microcirculatory systems. In order to evaluate the time course of its activity, the effect of HR on a provocation model of orthostatic oedema in healthy volunteers was used. After a 2 week placebo run-in period, 16 healthy volunteers were randomized to HR (2 tablets of 500 mg/day) of placebo for a further 3 weeks, in a double-blind parallel design. Oedema was provoked by standing motionless for 1 h, with measurement of leg volume before and afterwards. The procedure was undertaken at entry to the study and then weekly during the entire 5 week period. There were no significant differences in the extent of oedema produced by the orthostatic challenge during the 2 week run-in period or in the subjects who continued on placebo (approximately 90 arbitrary units i.e. approximately 48 ml). During the 3 week treatment with HR, however, there was a progressive reduction (-1.1, -5.9, and -7.6 arbitrary units after 1, 2, and 3 weeks, respectively) in the volume of induced oedema, which was significant after 2 and 3 weeks of treatment compared to the placebo group.

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