Imperatorin Influences Depressive-like Behaviors: A Preclinical Study on Behavioral and Neurochemical Sex Differences

Imperatorin, a naturally derived furanocoumarin, exerts promising neuropharmacological properties. Therefore, it might be applicable in the treatment of brain diseases such as depression. In the present project, we aimed to investigate the sex-dependent effects of imperatorin (1, 5, and 10 mg/kg) on behavior and neurochemistry associated with antidepressant effects. The depressive-like behaviors of male and female Swiss mice were investigated in a forced swim test (FST). Subsequently, High-Performance Liquid Chromatography (HPLC) was used to evaluate the level of serotonin, its metabolite, 5-HIAA, and noradrenaline, in mouse brains. The study revealed that only males responded to imperatorin (1 and 5 mg/kg) treatment and caused an antidepressant effect, such as with respect to depressive-like behaviors, lowering immobility time and increasing immobility latency. The HPLC analysis demonstrated that serotonin levels in the prefrontal cortex of females decreased with the middle dose of imperatorin (5 mg/kg), while in the male prefrontal cortex, the lower dose (1 mg/kg) boosted serotonin levels. There were no evident changes observed with respect to noradrenaline and serotonin metabolite levels in the male hippocampus. To conclude, we propose that imperatorin has antidepressant potential, seemingly only in males, influencing brain serotonin level, but the direct mechanism of action requires further investigation.     

Optically active dimethylsiloxane copolymers with nucleophilic chiral sulfur groups pendant to the polysiloxane chain

Polydimethylsiloxanes with part of the siloxane units bearing an optically active sulfoxide group were synthesized. These copolymers had chiral sulfur centres connected to the siloxane chain by a dimethylene bridge. They were obtained mostly by the kinetically controlled anionic ring-opening polymerization of 1-(2-organothioethyl)1,3,3,5,5-pentamethylcyclotrisiloxanes, followed by stereoselective oxidation of prochiral groups to yield partially enantiomeric sulfoxide groups. Sulfoxides bearing cyclic monomers were also used. Polymers were characterized by spectroscopy and polarimetry. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 879–888, 1997     

Molecular dynamics of poly(ethylene terephthalate)/poly(phenylene sulfide) nanocomposites with barium titanate

The relaxation processes and the properties of polymer/ceramic nanocomposites have been studied by the ¹H nuclear magnetic resonance methods. Nanocomposites of poly(ethylene terephthalate) PET and poly(phenylene sulfide) PPS with 0.25, 2.5 and 5% wt. barium titanate BT were prepared using a twin screw extruder and injection moulding machine. The spin-lattice relaxation time T₁, second moment M₂ and the motional parameters as e.g. the activation energies in the nanocomposites were investigated.     

Soil stress and deformation determination under a landing airplane on an unsurfaced airfield

This paper presents a multidisciplinary approach to a problem of soil–wheel interaction during the landing of an airplane on a grass airfield, with terramechanical analysis of the forces acting between a wheel and the surface. The experiment on stress and deformation state in soil under a wheel on touchdown was performed in the field. The soil stress state (major stress S1, minor stresses S2 and S3, stress invariant in an octahedral system, MNS and OCTSS) was determined with the use of an SST (stress state transducer), which was installed at 15 cm depth. Soil deformation was determined with an inertial measuring system, integrated with the SST. These soil data were captured exactly at the moment touchdown. In the experiment, a four-passenger, STOL multirole airplane was used and pilots performed two landing patterns: normal landing and emergency landing (without propeller thrust).     

GC/MS analysis of thermally degraded neuromelanin from the human substantia nigra

Neuromelanin (NM) is a complex polymer pigment found in catecholaminergic neurons of the human brain. The structure, formation pathway, and physiological function of NM have not yet been clarified, but interest in this polymer has been sparked by the suggestion that NM is involved in cell death in Parkinson's disease. In the current study, pyrolysis-gas chromatography/mass spectrometry analysis was applied for structural investigation of NM isolated from the human substantia nigra, using synthetic eumelanin and pheomelanin-type pigments as reference materials. None of the heterocyclic, sulfur-containing compounds being characteristic thermal degradation products of cysteinyldopamine-derived units of synthetic pheomelanin standard was detected in the pyrolysates of natural NM. The results suggest that nigral pigment isolated from normal brain tissue does not contain benzothiazine-type monomer units. Pyrolytic experiments in the presence of a derivatizing agent allowed identification of high levels of saturated and monounsaturated straight-chain C14-C18 fatty acids and led to the conclusion that a part of a lipid component is chemically bound to the NM macromolecule. The nigral pigment was also shown to be tightly associated with an isoprenoid-type compound.     

The Conjugate Addition-Cyclization of 3-Oxoacid Thioanilides to β-Nitrostyrenes. An Efficient Synthesis of Functionalized Thiophenes and their Transformation to Pyrroles

Summary. A new and simple method for synthesis of 2-, 3-, and 4-pyridylcarbonyl-2-aryliminothiophene derivatives based on the conjugate addition-cyclization of 3-oxoacid thioamides to β-nitrostyrenes was developed. Thiophene derivatives in acidic medium undergo ring transformation yielding corresponding pyrroles.     

The thermal transformations in Zn(No3)2-H2O (1:6) system

Using thermal analysis as well as isothermal gravimetric measurements, the thermal stability of the zinc nitrate(V) hexahydrate has been determined. Some intermediate products are the results of melting, evaporation, hydrolysis, polycondensation and decomposition processes occurring in the salt - water system up to 300°C. Solid phases were characterized by means of chemical analyses and X-ray powder diffraction method. This revised version was published online in July 2006 with corrections to the Cover Date.     

Measurement of Small One-Bond Proton–Carbon Residual Dipolar Coupling Constants in Partially Oriented C Natural Abundance Oligosaccharide Samples: Analysis of Heteronuclear JCH-Modulated Spectra with the BIRD Inversion Pulse

Two 2D J-modulated HSQC-based experiments were designed for precise determination of small residual dipolar one-bond carbon–proton coupling constants in ¹³C natural abundance carbohydrates. Crucial to the precision of a few hundredths of Hz achieved by these methods was the use of long modulation intervals and BIRD pulses, which acted as semiselective inversion pulses. The BIRD pulses eliminated effective evolution of all but ¹J_CH couplings, resulting in signal modulation that can be described by simple modulation functions. A thorough analysis of such modulation functions for a typical four-spin carbohydrate spin system was performed for both experiments. The results showed that the evolution of the ¹H–¹H and long-range ¹H–¹³C couplings during the BIRD pulses did not necessitate the introduction of more complicated modulation functions. The effects of pulse imperfections were also inspected. While weakly coupled spin systems can be analyzed by simple fitting of cross peak intensities, in strongly coupled spin systems the evolution of the density matrix needs to be considered in order to analyse data accurately. However, if strong coupling effects are modest the errors in coupling constants determined by the “weak coupling” analysis are of similar magnitudes in oriented and isotropic samples and are partially cancelled during dipolar coupling calculation. Simple criteria have been established as to when the strong coupling treatment needs to be invoked.