The effect of topical anesthesia on vocal fold motion

The objective of this study was to determine if topical anesthesia to the larynx and pharynx affects vocal fold motion during dynamic voice evaluation with transnasal flexible endoscopy. Transnasal dynamic laryngeal examinations of 10 patients with no voice complaints were evaluated by five blinded fellowship-trained laryngologists. Each patient was examined before and after application of topical anesthetic. Reviewers rated briskness of right and left vocal fold movement and longitudinal tension on a visual analogue scale. Statistical comparisons were made between individual subject scores before and after anesthetic application. Inter-rater reliability was also assessed. No statistical difference was observed between subject scores before and after anesthetic application. Average intraclass correlation coefficients were 0.643 and 0.591 for pre- and postanesthesia scores, respectively. Application of topical anesthesia to the larynx and pharynx does not affect vocal fold motion.     

Synthesis of some nitrogen heterocycles and in vitro evaluation of their antimicrobial and antitumor activity

Treatment of ethyl β-aryl-α-cyanoacrylate (2a, b) with thiourea, guanidine hydrochloride, and thiosemicarbazide in presence of anhydrous potassium carbonate in methanol led to formation of pyrimidine derivatives 3 and 5 and thiosemicarbazone derivative 9. Thiazole derivative 10 was prepared via cyclization of thiosemicarbazone derivative 9 with 4-methoxy phenacyl bromide. Acetylation of 3a, 5, and 10 with acetic anhydride yielded the acetoxy and N-acetyl derivatives 4, 6, and 11. The mass-spectral fragmentation patterns of nitrogen heterocycles were investigated to elucidate the structure of the prepared compounds. Biological studies of nitrogen heterocycles were carried out to investigate their antimicrobial and anticancer activities; it was found that compounds 5, 10, and 11 were highly active against bacteria and fungi, and compounds 3a and 3b were also active against bacteria and fungi.     

A new flavone glucoside from Stachys aegyptiaca

In addition to 5,7,3′-trihydroxy-6,4′-dimethoxyflavone, 5,7,3′-trihydroxy-6,8,4′-trimethoxyflavone, isoscutellarein, luteolin, and luteolin-7-O-glucoside, the methanol extract of the aerial parts of Stachys aegyptiaca yielded a new flavone identified as luteolin 3′,4′-dimethylether-7-O-β-D-glucoside on the basis of chemical and spectroscopic methods. Published in Khimiya Prirodnykh Soedinenii, No. 5, pp. 444–445, September–October, 2007.     

Design and synthesis of new thiobarbituric acid metal complexes as potent protease inhibitors: spectral characterization,thermal analysis and DFT calculations

Five novel metal complexes of thiobarbituric acid (TBAH) have been prepared with the general formulae: [Ti(TBA)₂(H₂O)₂]Cl₂·2H₂O, [Pd(TBA)₂]·4H₂O, Na[Ag(TBA)₂(H₂O)₂]·4H₂O, [Hg(TBA)₂(H₂O)₂] and [Ce(TBA)₂(H₂O)₃]SO₄·H₂O. The complexes have been fully characterized employing physicochemical and diverse spectroscopic techniques (IR, UV–Vis, mass and ¹H NMR) as well as thermal analysis. Elemental analyses and spectroscopic data have showed that the stoichiometries of all complexes were 1:2. Thermal analysis measurements indicated that the complexes have good thermal stability. Density functional theory calculations were carried out at the B3LYP levels of theory with a double basis set, LANL2DZ basis set for titanium, palladium, cerium atoms, or LANL2MB basis set for silver, mercury atoms and 6-31+G(d,p) basis set for the other atoms. The optimized geometry of the ligand and its complexes was obtained based on the optimized structures. The ligand and its metal complexes act as protease inhibitors and repressed their enzymatic activity significantly.     

Electrochemical determination of muscle relaxant drug tetrazepam in bulk form,pharmaceutical formulation,and human serum

Tetrazepam dissolved in the Britton-Robinson universal buffer of various pH values (2.5–11.5) containing 10 vol. % of ethanol was reduced at the mercury electrode in a single 2-electron irreversible step due to reduction of the 4,5 C=N double bond of the seven-membered ring. Differential pulse polarography (DPP) and adsorptive cathodic stripping voltammetry (AdCSV) techniques (Linear sweep LS, differential pulse DP and square-wave SW modes) for quantification of tetrazepam in bulk form and in myolastan tablets are presented. Moreover, the described linear sweep, differential pulse, and square-wave adsorptive cathodic stripping voltammetry was successfully applied in quantification of tetrazepam in spiked human serum without any prior extraction of the drug. The obtained results showed an increased sensitivity of the described electro-analytical procedures for the quantification of tetrazepam in the following order DPP, DP-AdCSV, LS-AdCSV, and SW-AdCSV, since the observed limits of tetrazepam quantitation by these electroanalytical techniques were 5 × 10⁻⁶ mol L⁻¹, 3 × 10⁻⁷ mol L⁻¹, 1 × 10⁻⁸ mol L⁻¹, and 3 × 10⁻⁹ mol L⁻¹, respectively.     

Trace determination of vardenafil hydrochloride in commercial formulation and human serum by adsorptive anodic stripping voltammetry at a carbon paste electrode

The electrochemical behavior of vardenafil HCl (VRL) at a carbon paste electrode (CPE) was investigated by cyclic voltammetry, and the mechanism of its oxidation was suggested and discussed. A simple Nujol-based CPE in combination with a sensitive square-wave adsorption anodic stripping voltammetry method was described for trace determination of VRL. The described method showed excellent performance for trace determination of VRL in its formulation “Levitra® tablets” without interference from excipients. The results were statistically compared with those obtained with an established HPLC method; nonsignificant differences were found between the described voltammetric and HPLC methods. The described stripping voltammetric method is highly sensitive (limit of detection?=?3?×?10^?10?mol?L^?1 and limit of quantitation?=?1?×?10^?9?mol?L^?1). It was successfully applied for the determination of VRL in spiked human serum without the necessity for pretreatment and/or time-consuming extraction steps prior to the analysis.     

A short range many-body potential for modelling bcc metals

The problem considered is the fitting of a many-body interaction potential to bulk crystal data. A parameterisation of the potential is assumed which is based on physical considerations. The free parameters are determined by using global optimization to perform a least squares fit, to a large number of crystal properties. This has been achieved for body centered cubic (bcc) materials. The approach adopted here fits the bcc crystal structure, as the preferred minimum energy configuration for tungsten, and also fits the dimer energetics and the elastic properties of crystalline tungsten.     

Electrodimerization of cyano-substituted derivatives of anthracene and naphthalene

The electrochemistry of cyano-substituted derivatives of naphthalene and anthracene was studied at different temperatures (298–233 K) using slow and fast scan voltammetry with a maximum scan rate of 500 V s⁻¹. All experimental evidence indicates the formation of a dimer by an E_revC_2rev process at the monoanion level. Rate constants for dimerization process were evaluated in six different polar solvents using theoretical working curves for an E_revC_2rev mechanism. Digital simulation was used to verify the accuracy of these rate constants. The results show that the polarity of the solvent influences the rate of dimerization reactions and that radical anions of the studied compounds dimerize under diffusion control.     

Effect of Sulfur Addition on the Redox State of Iron in Iron Phosphate Glasses

Hyperfine Interactions - Mössbauer, IR, and electrical conductivity were investigated in iron phosphate glasses, 40Fe2O3–60P2O5 (in mol%), containing sulfur ranging from 0 to 2, 4, 6,...     

Ion plated indium oxide : infrared and optical study

The high optical transparency of ion plated indium oxide combined with their mechanical hardness and good environmental stability have opened up numerous applications in the line of sophisticated optoelectronic devices. Indium is evaporated at a low oxygen pressure on to an ordinary glass substrate mounted under the cathode and biased by a r.f. generator at 13,6 M Hz. Infrared spectra are recorded in the range 5000–200 cm^?1 by A.T.R. and reflexion-absorption spectroscopy, and show between 800 and 200 cm^?1 bands due to stretching and bending modes predicted by a factor group analysis. A tentative assignment is made of the highest frequency. Last U.V. and visible spectra are discussed.