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Peroxisome proliferator activated receptor gamma (PPAR-γ) agonists are involved in the regulation of inflammatory responses and recent studies suggest that PPAR-γ ligands may have potential for the treatment of allergic airway disease. This study investigated the effect of the PPAR-γ agonist, rosiglitazone, on nasal mucous allergic inflammation and galectin-3 gene expression in a murine model of allergic rhinitis (AR mice). Rosiglitazone resulted in a statistically significant attenuation of the increased numbers of inflammatory cells and Th2 cytokine levels in nasal cavity lavage fluid of AR mice. Furthermore, the expression of galectin-3 in the nasal mucosa of AR mice was statistically significantly increased. Over-expression of galectin-3 was markedly suppressed by rosiglitazone treatment. These data suggest that the PPAR-γ agonist, rosiglitazone, may have potential in the development of therapies for allergic rhinitis.

Context. PG 1159-035, a pre-white dwarf with Teff ≃ 140000 K, is the prototype of both two classes: the PG 1159 spectroscopic class and the DOV pulsating class. Previous studies of PG 1159-035 photometric data obtained with the Whole Earth Telescope (WET) showed a rich frequency spectrum allowing the identification of 122 pulsation modes. Analyzing the periods of pulsation, it is possible to measure the stellar mass, the rotational period and the inclination of the rotation axis, to estimate an upper limit for the magnetic field, and even to obtain information about the inner stratification of the star. Aims. We have three principal aims: to increase the number of detected and identified pulsation modes in PG 1159-035, study trapping of the star's pulsation modes, and to improve or constrain the determination of stellar parameters. Methods. We used all available WET photometric data from 1983, 1985, 1989. 1993 and 2002 to identify the pulsation periods. Results. We identified 76 additional pulsation modes, increasing to 198 the number of known pulsation modes in PG 1159-035, the largest number of modes detected in any star besides the Sun. From the period spacing we estimated a mass M/M⊙= 0.59 ±0.02 for PG 1159-035, with the uncertainty dominated by the models, not the observation. Deviations in the regular period spacing suggest that some of the pulsation modes are trapped, even though the star is a pre-white dwarf and the gravitational settling is ongoing. The position of the transition zone that causes the mode trapping was calculated at rc/R* = 0.83 ± 0.05. From the multiplet splitting, we calculated the rotational period Prot = 1.3920 ± 0.0008 days and an upper limit for the magnetic field, B < 2000 G. The total power of the pulsation modes at the stellar surface changed less than 30% for ℓ = 1 modes and less than 50% for ℓ = 2 modes. We find no evidence of linear combinations between the 198 pulsation mode frequencies. PG 1159-035 models have not significative convection zones, supporting the hypothesis that nonlinearity arises in the convection zones in cooler pulsating white dwarf stars., La lista completa de autores que integran el documento puede consultarse en el archivo., Facultad de Ciencias Astronómicas y Geofísicas, Instituto de Astrofísica de La Plata

PG 0014+067 is one of the most promising pulsating subdwarf B stars for seismic analysis, as it has a rich pulsation spectrum. The richness of its pulsations, however, poses a fundamental challenge to understanding the pulsations of these stars, as the mode density is too complex to be explained only with radial and nonradial low degree (l < 3) p-modes without rotational splittings. One proposed solution, for the case of PG 0014+067 in particular, assigns some modes with high degree (l=3). On the other hand, theoretical models of sdB stars suggest that they may retain rapidly rotating cores, and so the high mode density may result from the presence of a few rotationally-split triplet (l=1), quintuplet (l=2) modes, along with radial (l=0) p-modes. To examine alternative theoretical models for these stars, we need better frequency resolution and denser longitude coverage. Therefore, we observed this star with the Whole Earth Telescope for two weeks in October 2004. In this paper we report the results of Whole Earth Telescope observations of the pulsating subdwarf B star PG 0014+067. We find that the frequencies seen in PG 0014+067 do not appear to fit any theoretical model currently available; however, we find a simple empirical relation that is able to match all of the well-determined frequencies in this star., 19 pages, preprint of paper accepted for publication in The Astrophysical Journal

BPM 37093 is the only hydrogen-atmosphere white dwarf currently known which has sufficient mass (~ 1.1 M_sun) to theoretically crystallize while still inside the ZZ Ceti instability strip (T_eff ~ 12,000 K). As a consequence, this star represents our first opportunity to test crystallization theory directly. If the core is substantially crystallized, then the inner boundary for each pulsation mode will be located at the top of the solid core rather than at the center of the star, affecting mainly the average period spacing. This is distinct from the "mode trapping" caused by the stratified surface layers, which modifies the pulsation periods more selectively. In this paper we report on Whole Earth Telescope observations of BPM 37093 obtained in 1998 and 1999. Based on a simple analysis of the average period spacing we conclude that a large fraction of the total stellar mass is likely to be crystallized., Comment: 7 pages, 3 figures, 3 tables, accepted for Astronomy & Astrophysics

Experimental data have suggested that BM-cell implantation can improve infarcted cardiac function. However, the number of implanted cells that survive is still unknown. The present study was performed to investigate whether implantation of autologous BM mononuclear cells (BM-MNCs) transfected with phVEGF165 can increase the number of surviving implanted cells, and enhance functional improvement of infarcted hearts in rabbits.Acute myocardial infarction (AMI) in rabbits was replicated by ligating the left anterior descending coronary artery, and animals were randomly divided into the following three groups: I AMI control group (n=7); II BM-MNCs transfected with phVEGF165 implantation group (n=7); III BM-MNCs implantation group (n=7). In addition, sham-operated (n=5) rabbits were randomly selected to serve as a non-infarction control group (VI). Animals for cell implantation received intramyocardial injections of autologous BM-MNCs 14 days after AMI. Echocardiography and hemodynamic studies were performed to evaluate cardiac structure and function 28 days after implantation. The implanted sites were examined using immunofluorescence to identify the phenotypes and number of the labelled cells. Reverse transcriptase (RT)-PCR and Western blot analysis were performed to detect the expression of hVEGF165 gene and VEGF165 protein respectively.Failed cardiac function produced by AMI was significantly improved in Groups II and III 28 days after cell implantation. BM-MNCs transfected with phVEGF165 implantation conferred a further improvement of cardiac function, with significant changes of all assessed parameters when compared with BM-MNCs implantation alone (all P0.05). The implanted cells demonstrated myogenic differentiation with the expression of Troponin T and organized contractile proteins. The positive staining for Factor VIII-related Ag indicated the induction of angiogenesis in the infarct area. The percentage of Brdu-positive myocyte, endothelial cells was 75+/-%, 34.1+/-4.6% in Group II, significantly higher than that in Group III(51+/-7%, 11.3+/-2.5% respectively, P0.05). RT-PCR analysis demonstrated exclusive expression of hVEGF165 gene in Group II, and Western blot showed the expression of VEGF165 protein was significantly higher in Group II than in Group III (P0.05).Implantation of BM-MNCs transfected with phVEGF165 can increase the number of implanted cells surviving, and enhance the impaired cardiac function after AMI.

Development plan and some progress have been made for amplifier of SGIII laser facility. According to this plan, a single-segment amplifier has been designed and experimented to test key units and correct simulating code in National Laboratory of Laser Fusion of China. The preliminary design for 4 X 2 X 3 amplifier prototypes, including amplifier modules, pulsed power, assembly equipment, and optics for SGIII will be finished.

A stretchable patch antenna (SPA) whose frequency is tuned by a planar dielectric elastomer actuator (DEA) is presented in this paper. This mechanically reconfigurable antenna system has a configuration resembling a pre-stretched silicone belt. Part of the belt is embedded with a layer of conductive liquid metal to form the patch antenna. Part of the belt is sandwiched between conductive electrodes to form the DEA. Electrical activation of the DEA results in a contraction of the patch antenna, and as a result, in a variation of its resonance frequency. Design and fabrication steps of this system are presented. Measurement results for deformation, resonance frequency variation and efficiency of the patch antenna are also presented.

The tensile properties and fracture characteristics of two kinds of Ag-containing Al-Li-Cu-Mg-Zr alloys with different aging conditions have been studied from 290 to 77 K. The results show that the tensile strength and ductility of the alloys improved significantly with a decrease in test temperature from 153 to 77 K, except for the elongation of some alloys in certain aging conditions. Planar slip behavior is the predominant deformation mode for the natural-, under-, and peak-aged samples when tested at room temperature, but the slip distribution is fairly homogeneous as the test temperature is reduced to 77 K. The different modes of tensile fracture are closely associated with the aging time and test temperatures. The improvement in cryogenic ductility of the alloys can be attributed to an increase in deformation homogeneity. The tensile fracture behavior of the alloys at ambient and cryogenic temperatures are discussed.

The effects of various Sc contents on the microstructure, tensile properties, and fracture behavior of Al-Li-Cu-Mg-Zr alloy in the natural- and artificial-aged conditions have been investigated. The temperature dependence of the tensile properties of these alloys was determined in the rolling direction from 290 to 77 K. As the temperature decreased, the strength and ductility of the Sc-containing alloys increased. In all the alloys, δ′ (A13Li) and S′ (Al2CuMg) are the main strengthening phases, and in the Sc-containing alloys, A13Li/A13Sc particles also were effective in improving the strength. The variation of positron annihilation parameters with test temperature was also measured.

We observed the Leonid meteor storm in 1998 and 1999. The light curves extracted from the 2-dimensional images of the bright Leonid meteors clearly show the sub-structures, which are consistent with the generally accepted dustball meteor model (Hawkes & Jones, 1975).

The microstructure and cryogenic tensile properties of an Al-Li-Zn-Zr alloy in different aging conditions have been studied. The temperature dependence of the tensile properties of the alloy were evaluated from ambient to liquid nitrogen temperature in the long transverse direction. The results show that the tensile strength and elongation of the alloy are much increased with the decrease of test temperature. The variation in tensile fracture mode and deformation behavior are proved to depend on the aging conditions and test temperature closely. The effect of microstructure on tensile deformation and fracture behavior of the alloy at room and cryogenic temperatures have been discussed. δ′ particles are the major fractor to the improvement of ductility for the alloy at low temperatures.

Under defined conditions E. coli were subjected to repeated chlorine disinfections 10 times. The survival E. coli at 30 s (A10), and the survival E. coli at 10 min (B10) had no difference in resistance to chlorine to their original strain (A0). However, the compound E. coli (C10) survived at various contact time showed an increased resistance than their original strain (A10), the degree of increased resistance varying with different conditions of disinfection. E. coli C1(0) lost its increased resistance after it has been passaged 10 times on nutrient agar.

Two novel diterpendoids, pseudolaric acids A and B (PA, PB) first isolated from the root of Pseudolarix kaempferi Gorden in China, have been reported to possess significant antifertile activities in rats, hamsters, rabbits, and dogs. The present study demonstrated that neither PA nor PB had estrogenic and antiestrogenic activities, they also did not inhibit deciduous formation. When an effective dose of PB 30 mg.kg-1 was given on d 6 of pregnancy and the hormonal determinations were done on d 8 and d 12 of pregnancy, the progesterone, estradiol and prostaglandins E, F levels in plasma and the uterine prostaglandin E, F levels were not significantly reduced vs those of the control rats. The human uterus was used as the experimental material in vitro. PA and PB 200 micrograms.ml-1 cultural medium (McCoy's 5a medium) damaged only a part of the decidual and trophoblast cells. In partially depolarized isolated uterine smooth muscles of early pregnant rats, PA and PB caused a decline in the contractile tension. A low dose of PB 2 mg.kg-1.d-1 was given ig on d 6-12 of pregnancy in rats caused the body weight and the length of fetuses and the placental weight value significantly lower than those of the control. Thus, ischemia due to the vasoconstrictor effect is probably of great, and sometimes of supreme, importance.

Under defined conditions, E. coli bacteriophage f2 was subject to repeated disinfection by chlorine 10 times. The survival bacteriophage f2 was compared with its original strain in resistance to chlorine. Experimental results showed that bacteriophage f2 increased its resistance after chlorine disinfection. The increased resistance varied under different conditions. The higher the pH, the greater the increased resistance. The survival bacteriophage f2 maintained its increased resistance though it was passaged 10 times in nutrient broth. The reason for the increased resistance of bacteriophage f2 after chlorine disinfection was probably the chlorine-induced mutation or spontaneous chlorine-resistant mutation.

We present the data and initial results from a combined Hubble Space Telescope (HST)/IUE/ground-based spectroscopic monitoring campaign on the Seyfert 1 galaxy NGC 5548 that was undertaken in order to address questions that require both higher temporal resolution and higher signal-to-noise ratios than were obtained in our previous multiwavelength monitoring of this galaxy in 1988-1989. IUE spectra were obtained once every 2 days for a period of 74 days beginning on 1993 March 14. During the last 39 days of this campaign, spectroscopic observations were also made with the HST Faint Object Spectrograph (FOS) on a daily basis. Ground-based observations, consisting of 165 optical spectra and 77 photometric observations (both CCD imaging and aperture photometry), are reported for the period 1992 October-1993 September, although many of the data are concentrated around the time of the satellite-based program. These data constitute a fifth year of intensive optical monitoring of this galaxy. In this contribution we describe the acquisition and reduction of all of the satellite and ground-based data obtained in this program. We describe in detail various photometric problems with the FOS and explain how we identified and corrected for various anomalies.

Progesterone concentrations in peripheral plasma were determined by competitive protein binding assay during normal human menstrual cycles and in pregnancy. In addition, to investigate the mode of action of anordrin (a postcoital pill) and AF-75 (an effective antifertility nonsteroid in animals) and to evaluate their clinical efficacy, the effects of these 2 chemicals on plasma progesterone levels were also studied. 33 women with normal menstrual cycle and fertility gave blood samples on various days before and after ovulation, according to basal body temperature changes. During the follicular phase, the plasma progesterone level was less than 1 ng/ml (mean .39). After ovulation, the progesterone levels rose gradually, reaching maximal values of 7-15 ng/ml 6-9 days before menstruation. Then the concentrations fell off gradually to below 2 ng/ml on the day before or on the first day of menses. 77 pregnant women at various stages of pregnancy gave blood samples. Plasma progesterone levels during early pregnancy were similar to those of luteal phase. The concentrations gradually rose to a peak in late pregnancy, with the maximal figure being over 130 ng/ml, although there were individual variations. 10 women of child-bearing age were given 7.5 mg of anordrin daily 1-5 days before ovulation, 5 times. Plasma progesterone levels on various days after ovulation were assayed and compared with untreated control cycles. Ovulation did occur in every medicated cycle, but the maximal progesterone values in luteal phase were lower than those of untreated cycles (P .01), and luteal periods were shortened (P .05). Administration of AF-75 showed no conspicuous effect on ovulation or development of corpus luteum in normal women.

Naturally occurring nucleosides of pyrrolo [2,3-d] pyrimidine, tubercidin, sangivamycin and toyocamycin were known as antibodies not only for their potent antitumor activity but also for their significant antiviral effects. However, none of them was developed to be a useful drug due to their high toxicity. In order to reduce the toxicity of this kind of compounds and reveal the relationship between structure and biological activity, a series of acyclic analogues of tubercidin with varied 4-substituted amino groups were synthesized. 4-chlor-pyrrolo (2,3-d) pyrimidin was used as starting material which reacted with 1,3-dibenzyloxy-glycerol-2-chloro-methylether by direct sodium salt glycosylation procedure provided the key intermediate (IX). After hydrogenation, amination of compound IX gave the final free hydroxy products. All the compounds were tested in vitro against HSV-1 and Cox B6. Only three of them (XI6, XI7, XI9) showed certain activities against Cox B6.

Since pulsating subdwarf B (sdBV or EC14026) stars were first discovered (Kilkenny et al, 1997), observational efforts have tried to realize their potential for constraining the interior physics of extreme horizontal branch (EHB) stars. Difficulties encountered along the way include uncertain mode identifications and a lack of stable pulsation mode properties. Here we report on Feige 48, an sdBV star for which follow-up observations have been obtained spanning more than four years, which shows some stable pulsation modes. We resolve the temporal spectrum into five stable pulsation periods in the range 340 to 380 seconds with amplitudes less than 1%, and two additional periods that appear in one dataset each. The three largest amplitude periodicities are nearly equally spaced, and we explore the consequences of identifying them as a rotationally split l=1 triplet by consulting with a representative stellar model. The general stability of the pulsation amplitudes and phases allows us to use the pulsation phases to constrain the timescale of evolution for this sdBV star. Additionally, we are able to place interesting limits on any stellar or planetary companion to Feige 48., accepted for publication in MNRAS