Concentrations of garenoxacin in plasma, bronchial mucosa, alveolar macrophages and epithelial lining fluid following a single oral 600 mg dose in healthy adult subjects

A microbiological assay was used to measure concentrations of garenoxacin (BMS-284756) in plasma, bronchial mucosa (BM), alveolar macrophages (AM) and epithelial lining fluid (ELF), following a single 600 mg oral dose. Twenty-four healthy subjects were allocated into four nominal time intervals after the dose, 2.5-3.5, 4.5-5.5, 10.5-11.5 and 23.5-24.5 h. Mean concentrations in plasma, BM, AM and ELF, respectively, for the four nominal time windows were for 2.5-3.5 h 10.0 mg/L (S.D. 2.8), 7.0 mg/kg (S.D. 1.3), 106.1 mg/L (S.D. 60.3) and 9.2 mg/L (S.D. 3.6); 4.5-5.5 h 8.7 mg/L (S.D. 2.2), 6.0 mg/kg (S.D. 1.9), 158.6 mg/L (S.D. 137.4) and 14.3 mg/L (S.D. 8.2); 10.5-11.5 h 6.1 mg/L (S.D. 1.9), 4.0 mg/kg (S.D. 1.4), 76.0 mg/L (S.D. 47.7) and 7.9 mg/L (S.D. 4.6); and 23.5-24.5 h 2.1 mg/L (S.D. 0.5), 1.7 mg/kg (S.D. 0.7), 30.7 mg/L (S.D. 12.9) and 3.3 mg/L (S.D. 2.3). Concentrations at all sites exceeded MIC(90)s for the common respiratory pathogens Haemophilus influenzae (0.03 mg/L), Moraxella catarrhalis (0.015 mg/L) and Streptococcus pneumoniae (0.06 mg/L). These data suggest that garenoxacin should be effective in the treatment of community-acquired pneumonia and chronic obstructive pulmonary disease.

Local and segmental dynamics in homopolymer and triblock copolymers with one semicrystalline block

Thermally stimulated depolarization currents, TSDC, experiments have been performed on a series of poly(styrene)-b-poly(butadiene)-b-poly(epsilon-caprolactone) triblock copolymers SBC with different proportions of the poly(epsilon-caprolactone) crystallizable block, PCL. The morphology of the segregated microphases varies with the PCL content and has been observed by transmission electron microscopy. The crystallinity of the PCL block is estimated by wide angle x-ray scattering, WAXS. The relaxation times distribution is extracted by a numerical decomposition of the TSDC spectra and it is shown that this distribution is not significantly changed on going from the homopolymer to the triblock copolymer with 16 wt % to 77 wt % of PCL in the original samples. Better segregation of the mesophase structure is reached when the samples are annealed at 413 K and important variations in the TSDC and WAXS spectra are observed as a result of the thermal treatment. For the S09B14C77 triblock copolymer the results obtained can be explained by postulating the existence of a rigid amorphous phase in the PCL block. Such rigid amorphous phase is located between the core-shell cylinders formed by the other blocks [with poly(styrene)(PS) as core and poly(butadiene)(PB) as shell] and is constrained by undulated lamellae of crystalline PCL material. In the case of S35B15C50 triblock copolymer, an important amount of diffuse PS-PCL interphase where the homopolymers are mixed must be present before annealing. The results for the material with the less abundant PCL block are explained as a result of the confinement in nanotubes of PCL surrounded by PB embedded in a vitreous PS matrix. Broadband dielectric experiments on these same materials confirm the results obtained by TSDC spectroscopy.

Inhibitory and facilitatory effects of cue onset and offset

The response speed to a visual target is modulated by the position of previous events (cues) even if their position is not predictive of the target position. The modulation has been considered biphasic, with an early facilitatory and a later inhibitory component. We conducted three experiments that investigated the importance of the onset and offset features of the cue for the facilitatory and inhibitory effects and estimated their separate and joint effects. The two possible target locations, one in the right and one in the left visual field, were indicated by two empty boxes, and the cue consisted of the onset and/or offset of an arrowhead located just under one of the two boxes. Different time intervals were used between cue and target. Subjects were instructed to ignore the cue and to respond to the target (a cross inside one of the two boxes). The data showed only consistent effects of inhibition (inhibition of return) with the long intervals, but the pattern was different depending on the cue type. The amount of inhibition was much greater when the onset of the cue was followed by its offset. Apparently, inhibition of return depended on the dynamic changes of the cue.

Calcium antagonist properties of the bisbenzylisoquinoline alkaloid cycleanine

The alkaloid cycleanine ([12aR-(12aR,24aR)]-2,3,12a,13,14,15,24,24a-octa hydro-5,6,17,18- tetramethoxy-1,13-dimethyl-8, 11:20,23-dietheno-1H,12H [1,10]dioxacyclooctadecino[2,3,4-ij:11,12,13-i'j']diisoquinolin e) was extracted from the bulbs of Stephania glabra (Roxb) Miers and its effects on cardiac and smooth muscle preparations were studied and compared to those of nifedipine (1,4-dihydro-2, 6-dimethyl-4-(2-nitrophenyl)-3,5-pyridine dicarboxylic acid dimethylesther). Cycleanine inhibited the KCl-induced contraction of rabbit aortic rings with higher potency than nifedipine. IC50s for cycleanine and nifedipine were 0.8 and 7.10(-9) M respectively. Cycleanine had minor effects on the norepinephrine-induced contraction of rabbit aortic rings. Cycleanine and nifedipine also depressed the contraction of rat ventricular preparations but with lower potency (IC50 = 3 and 0.03.10(-6) M respectively). Action potential duration of rat right ventricular strips was decreased by both compounds. L-type Ca-current (ICaL) of single rat ventricular cardiomyocytes was inhibited by cycleanine in a voltage- and frequency-dependent manner. With a higher potency nifedipine inhibited ICaL in a tonic and almost frequency-independent manner. The results suggest that cycleanine can act as a potent vascular selective Ca-antagonist.

Characterization of the atherosclerotic plaque in the internal mammary artery

The current study examines, at both structural and ultrastructural levels, representative segments of internal mammary arteries obtained from 15 male patients, ranging in age from 45 to 75 years, with signs or symptoms of coronary heart disease. These segments were obtained at the time of coronary bypass surgery. Of the 15 segments examined, only 2 were found to have atherosclerotic plaques. In other segments, only an intimal thickening similar to that observed during aging was found. There was evidence of endothelial cell loss and defects of internal elastic lamina in the present study; however, there was no evidence of lipid accumulation in the intimal region. This observation agrees with previous findings that indicate that lipid accumulation is not a necessary factor for the formation of atherosclerotic plaques. During the study microfilament bundles, the so-called "stress fibers," were also observed in the cytoplasm of the luminal side of endothelial cells. Stress fibers are known to be present in some endothelial cells in some pathologies such as regeneration after injury or hypertension. One of the features of the atherosclerotic plaques from an internal mammary artery was the presence of cells with contractile and synthetic phenotypes (contractile and synthetic smooth muscle cells), as well as cells with intermediate features. Cells with similar characteristics have also been observed during the development of the early stages of atherosclerosis, during embryological development of vessels, after experimental excimer laser treatment, and in primary cell culture. To our knowledge, this is the first report showing the ultrastructural features of the atherosclerotic plaques in the internal mammary artery.

A review of esthetic alternatives for the restoration of anterior teeth

PURPOSE

This article describes different options for the esthetic treatment of anterior teeth, starting with minimally invasive procedures, such as facial surface bleaching and bonding with composites.

METHODS

The importance of metal ceramic restorations, porcelain shoulder techniques, and metal free ceramics are also emphasized. The options are carefully demonstrated to identify advantages and limitations of each technique.

Metabolism of (-)-(S)-nicotine in the isolated perfused rabbit lung

The metabolism of (-)-(S)-nicotine has been investigated following intratracheal administration to the recirculating perfused rabbit lung model. The metabolic products present in the perfusate were identified by co-chromatography (HPLC and GC) with authentic standards and quantified by HPLC. After the 180 min perfusion period, nicotine was found to be metabolically transformed to cotinine (33.7%), 3-hydroxycotinine (10.4%), cotinine-1-N-oxide (3.4%) and nicotine-1'-N-oxide (14.4%). Norcotinine, nornicotine, 3-pyridyl-4-oxo-N-methylbutyramide and an uncharacterised metabolite were also detected in low amounts. Following the perfusion experiment, part of the lung tissue was homogenised in the presence of [14C]-sodium cyanide. Subsequent analysis of the homogenates indicated the formation of 2'-cyanonicotine, 1'-cyanomethylnornicotine and the diastereoisomeric 5'-cyanonicotines.