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Background Adenosine monophosphate (AMP) may reflect airway inflammation and hyperresponsiveness, but relationship between AMP and histamine (His, a conventional stimulus) bronchial provocation test (BPT) in asthma is not fully elucidated. Objectives To compare both BPTs and determine their utility in reflecting changes of asthmatic symptoms. Methods BPTs were performed in a cross-over fashion, at 2-4 day intervals. Cumulative doses eliciting 20% FEV1fall (PD20FEV1), diagnostic performance and adverse events (AEs) were compared. Patients with PD20FEV1 lower than geometric mean were defined as responders, otherwise poor responders. Patients with uncontrolled and partly controlled asthma, who maintained their original inhaled corticosteroids therapy, underwent reassessment of airway responsiveness and asthmatic symptoms 3 and 6 months after. Results Nineteen uncontrolled, 22 partly controlled and 19 controlled asthmatic patients and 24 healthy subjects were recruited. Lower PD20FEV1 geometric means were associated with poorer asthma control in His-BPT (0.424 μmol vs 1.684 μmol vs 3.757 μmol), but not AMP-BPT (11.810 μmol vs 7.781 μmol vs 10.220 μmol). Both BPTs yielded similar overall diagnostic performance in asthma (area under curve: 0.842 in AMP-BPT vs 0.850 in His-BPT). AEs, including wheezing and tachypnea, were similar and mild. Ten patients with uncontrolled and 10 partly controlled asthma were followed-up. At months 3 and 6, we documented an increase in PD20FEV1-AMP and PD20FEV1-His, which did not correlate with reduction asthmatic symptom scores. This overall applied in responders and poor responders of AMP-BPT and His-BPT. Conclusion Despite higher screening capacity of well-controlled asthma, AMP-BPT confers similar diagnostic performance and safety with His-BPT. AMP-BPT might not preferentially reflect changes asthmatic symptoms. [ABSTRACT FROM AUTHOR]

Introduction The convenient measure to predict efficacy of leukotriene receptor antagonist is lacking. Objectives To determine if leukotriene D4 inhalation challenge predicts short-term efficacy of montelukast in asthma. Methods In this open-labelled 28-day trial, 45 patients with asthma were allocated to leukotriene-sensitive and leukotriene-insensitive group to receive montelukast monotherapy (10 mg, once daily) based on the positive threshold of leukotriene D4 inhalation challenge test (4.800 nmol). Miscellaneous measurements comprised fractional exhaled nitric oxide, methacholine inhalation challenge, Asthma Control Test and Asthma Quality of Life Questionnaire. Peak expiratory flow was self-monitored throughout the treatment. End point assessments were performed 3 to 5 days after montelukast withdrawal. (Registration: ) Results Twenty-three patients in leukotriene-sensitive group and 10 leukotriene-insensitive group completed the study. Both groups differed neither in 28-day peak expiratory flow rate nor in maximal weekly peak expiratory flow (both P > 0.05). However, minimal weekly peak expiratory flow was significantly higher in leukotriene-insensitive group throughout the treatment course (all P < 0.05) except for week 1 ( P > 0.05). Both groups did not differ statistically in the post-treatment improvement in forced expiratory volume in 1 s ( FEV1) predicted% prior to inhalation challenge, fractional exhaled nitric oxide or the airway responsiveness to leukotriene D4 or methacholine (all P > 0.05). There was a marked increase in Asthma Control Test score and the symptom score of Asthma Quality of Life Questionnaire in both groups (both P < 0.05). The overall significance of Logistic regression model was unremarkable ( P = 0.467). Conclusion Responsiveness to inhaled leukotriene D4 alone might not be sufficient to predict the short-term efficacy of montelukast monotherapy in patients with asthma. [ABSTRACT FROM AUTHOR]

Background: Response-dose ratio (RDR) and cumulative provocative dosage (PD) are useful indices reflecting airway responsiveness in asthma. Objectives: To compare the diagnostic value of RDR and PD, by conducting leukotriene D (LTD-BPT) and methacholine bronchial provocation test (MCh-BPT), in different asthma control levels. Methods: Healthy subjects and asthmatic patients underwent LTD-BPT and MCh-BPT, at 2-14-day interval. This entailed assessment of the distribution characteristics, correlation, and diagnostic value of PD inducing 20 % fall in forced expiratory volume in one second (PDFEV) and the RDR, defined as FEV fall (%) at the final step divided by the corresponding provocative dosage. Results: Twenty uncontrolled, 22 partly controlled, 20 controlled asthmatics, and 21 healthy subjects were enrolled. LogRDR was positively correlated with logPDFEV in both BPTs (all P < 0.05). Poorer asthma control was associated with significantly lower PDFEV and higher RDR (both P < 0.05). The differences in PDFEV and RDR between partly controlled and controlled asthma were unremarkable (both P > 0.05). Compared with logPDFEV, the logRDR yielded similar diagnostic values in both BPTs. A lower percentile of RDR (≤25th percentile) was associated with higher baseline FEV ( P < 0.05) and an increased proportion of well-controlled asthmatic patients. The combination of RDR and PDFEV led to an increased diagnostic value compared with either parameter alone. Conclusions: RDR is a surrogate of PDFEV for BPTs in asthma. This finding was not modified by different asthma control levels or the types of bronchoprovocants. [ABSTRACT FROM AUTHOR]

Abstract: Using the first-principles density-functional theory within the generalized gradient approximation (GGA), we have investigated the structural, elastic, mechanical, electronic, and optical properties and phase transition of CuInO2. Structural parameters including lattice constants and internal parameter, pressure effects and phase transition pressure were calculated. We have obtained the elastic coefficients, bulk modulus, shear modulus, Young''s modulus and Poisson''s ratio. We find that two phases of CuInO2 are indirect band gap semiconductors (F–Γ and H–Γ for 3R and 2H, respectively). Optical properties, including the dielectric function, refractive index, extinction coefficient, reflectivity, absorption coefficient, loss function and optical conductivity have been obtained for radiations of up to 30eV. [Copyright &y& Elsevier]

Two three-dimensional (3D) Fe(II) porous metal–organicframeworks(MOFs) [Fe2(H0.67bdt)3]·13H2O (1·13H2O) and [Fe3(ox)(H0.67bdt)3(H2O)2]·solvent (2·solvent) (H2bdt =5,5′-(1,4-phenylene)bis(1H-tetrazole); H2ox = oxalicacid; solvent = 10H2O and 9CH3OH for 2·9MeOH and 6H2O and 5C4H9OHfor 2·5n-BuOH) were solvothermallysynthesized and characterized. The X-ray structure analysis revealsthat complex 1·13H2O is constructed fromone-dimensional (1D) {Fe(tz)3}n(tz = tetrazolate) chains which are linked through the phenyl tethersof the bdt ligands into a 3D microporous framework. In the case ofcomplex 2·solvent, the linear trinuclear [Fe3(tz)6] units are linked by ox2–bridges to form 1D {Fe3(tz)6(ox)}nchains, which are also extended into a 3D microporousframework linked by the bdt ligands. Their frameworks can be simplifiedas the same topological network (46,66,83)(42,63,8). The substructure of the1D {Fe(tz)3}nchain in 1·13H2O consists of spin-crossover (SCO) activeFe1 ions and low spin (LS) Fe2 ions alternately, while the trinuclearunit in 2·solvent contains a partial high spin (HS)Fe1 ion and two terminal HS Fe2 ions. Magnetic susceptibility measurementsreveal that complex 1·13H2O presentsan incomplete gradual SCO behavior. Although complex 2·solvent also has the SCO active Fe1 ions, the spin state changeis extremely small and the antiferromagnetic property is primarilyobserved. [ABSTRACT FROM AUTHOR]

From December 2007 to November 2008, an in situ experiment was conducted to study the effects of simulated nitrogen deposition on the soil respiration in a Neosinocalamus affinis plantation in Rainy Area of West China. Four treatments were installed, i.e., 0 (CK), 50, 150, and 300 kg N·hm-2·a-1, and soil respiration rate was measured by infrared gas analyzer. In the test plantation, soil respiration rate had a distinct seasonal fluctuation, with the highest (3.36±0.20 μmol·m-2·s-1) by the end of July and the lowest by the end of February (0.33±0.07 μmol·m-2·s-1). There was a significant exponential relationship (P<0.001) between soil respiration rate and soil temperature, and the temperature at 10 cm soil depth explained 91.6% of the seasonal change of soil respiration. However, less relationship was observed between soil respiration rate and soil moisture content (R2=0.0758). From June to November 2008, the contribution of root respiration to total soil respiration ranged from 46% to 59%. The annual release amount of CO2 in treatments 50, 150, and 300 kg·hm-2·a-1 was 23.6%, 46.7%, and 50.5% lower than that in CK (2.17×104 kg ·hm-2), and the Q10 value of soil respiration rate in treatments 0, 50, 150, and 300 kg·hm-2·a-1 was 3.72, 3.51, 2.95, and 2.71, respectively. [ABSTRACT FROM AUTHOR]

A pot experiment with controlled water supply was conducted to study the effects of drought stress (continuous drought for 0 d, 5 d, 10 d, … 45 d) on the photosynthetic characteristics and growth of Jatropha curcas seedlings under different nitrogen fertilization levels (N0, 0 kg N · hm-2; NL, 96 kg N · hm-2; NM, 288 kg N · hm-2; NH, 480 kg N · hm-2). With the enhancement of drought stress, the leaf relative water content (RWC1), height growth (Zh), basal diameter growth (Zd, leaf area (La), net photosynthetic rate ( Pn), transpiration rate (Tr), and stomatal conductance (Gs) decreased significantly (P < 0.01), irrespective of nitrogen fertilization level. The chlorophyll (Chl) content and water use efficiency (WUE) increased first and decreased then, while the intercellular CO2, concentration (Ci) had an increase after an initial decrease. Under adequate water condition, nitrogen fertilization promoted the photosynthesis and growth of J. curcas seedlings to different degrees, and the effect was increased with increasing nitrogen fertilization level. Under drought stress, the effects of nitrogen nutrition on the photosynthesis and growth were dependent on drought intensity and nitrogen fertilization level. Specifically, increasing nitrogen fertilization level could promote the photosynthesis and growth of J. curcas seedlings under mild drought, the promotion effect of NM was higher than that of NL and NH under moderate drought, and NL had the best promotion effect while NH weakened the effect or made it negative under severe drought. [ABSTRACT FROM AUTHOR]