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The autoionization mechanisms of dense nP3/2 (n = 20–97) Rydberg gases of 87Rb atoms in the spontaneous evolution were investigated for the first time. By observing the characteristic time of the electrons generated through autoionization process, the dependence of autoionization mechanisms (black‐body radiation, electron–Rydberg collision, and Penning ionization) on the principal quantum number n of initial nP states was demonstrated. The dependence on the number n in nP Rydberg atoms is similar to those in nD Rydberg atoms. [ABSTRACT FROM AUTHOR]

Comparative pharmacokinetic profiles of diaveridine following single intravenous and oral dose of 10 mg/kg body weight in healthy pigs and chickens were investigated, respectively. Concentrations of diaveridine in plasma samples were determined using a validated high-performance liquid chromatography-ultraviolet ( HPLC- UV) method. The concentration-time data were subjected to noncompartmental kinetic analysis by WinNonlin program. The corresponding pharmacokinetic parameters in pigs or chickens after single intravenous administration were as follows, respectively: t1/2 β (elimination half-life) 0.74 ± 0.28 and 3.44 ± 1.07 h; V d (apparent volume of distribution) 2.70 ± 0.99 and 3.86 ± 0.92 L/kg; ClB (body clearance) 2.59 ± 0.62 and 0.80 ± 0.14 L/h/kg; and AUC0-∞ (area under the blood concentration vs. time curve) 4.11 ± 1.13 and 12.87 ± 2.60 μg∙h/mL. The corresponding pharmacokinetic parameters in pigs or chickens after oral administration were as follows, respectively: t1/2 β 1.78 ± 0.41 and 2.91 ± 0.57 h; Cmax (maximum concentration) 0.43 ± 0.24 and 1.45 ± 0.57 μg/ mL; Tmax (time to reach Cmax) 1.04 ± 0.67 and 3.25 ± 0.71 h; and AUC0-∞1.33 ± 0.55 and 9.28 ± 2.69 μg∙h/ mL. The oral bioavailability (F) of diaveridine in pigs or chickens was determined to be 34.6% and 72.2%, respectively. There were significant differences between the pharmacokinetics profiles in these two species. [ABSTRACT FROM AUTHOR]

The Changsha region was an important place in China during the heyday of lacquerwares, from the Warring States Period to the Western Han Dynasty (476 bc - ad 9), when lacquerwares were used with varied styles and beautiful ornamentations. However, the process used to make lacquerware was previously unknown. By analysing samples of fragments of lacquerware found in the Changsha region dating back to between the Mid-Warring States Period and the Mid-Western Han Dynasty (390-87 bc), this paper demonstrates the varied constitution of the ground layer by analysing the features of the technique using non-destructive methods. It also shows that the use of potassium alum, gypsum, carbon and brochantite as fillers in the ground layer can be dated back to the Mid-Warring States Period. Furthermore, a comparison of techniques for ground layers from the Changsha region and other areas in China during this period is proposed on this basis. [ABSTRACT FROM AUTHOR]

Sensitivity to azoxystrobin and kresoxim-methyl of 80 single-spore isolates of Magnaporthe oryzae was determined. The EC50 values for azoxystrobin and kresoxim-methyl in inhibiting mycelial growth of the 80 M. oryzae isolates were 0.006-0.056 and 0.024-0.287 µg mL−1, respectively. The EC50 values for azoxystrobin and kresoxim-methyl in inhibiting conidial germination of the M. oryzae populations were 0.004-0.051 and 0.012-0.105 µg mL−1, respectively. There was significant difference in sensitivity to azoxystrobin or kresoxim-methyl between the tested isolates representing differential sensitivity to carbendazim ( MBC) and kitazin P ( IBP); however, there was no correlation between this difference in sensitivity to azoxystrobin or kresoxim-methyl and sensitivity to MBC or IBP, indicating that there was no cross-resistance between azoxystrobin or kresoxim-methyl and MBC or IBP. In the protective and curative experiments, kresoxim-methyl exhibited higher protective and curative activity than azoxystrobin when applied at 150 and 250 µg mL−1 accordingly, while azoxystrobin exhibited stronger inhibitory activity against M. oryzae isolates than that of kresoxim-methyl in the in vitro test. The results of field experiments also suggested that both azoxystrobin and kresoxim-methyl at 187.5 g.a.i. ha−1 gave over 73% control efficacy in both sites, exhibiting excellent activity against rice blast. Taken together, azoxystrobin and kresoxim-methyl could be a good substitute for MBC or IBP for controlling rice blast in China, but should be carefully used as they were both at-risk. [ABSTRACT FROM AUTHOR]

To analyze the pathogenesis of persistent and refractory haematospermia and to evaluate the aetiological diagnostic value of magnetic resonance imaging ( MRI) for this type of haematospermia. Clinical data from 102 patients with persistent and refractory haematospermia was retrospectively analysed. Data collected included history, symptoms, as well as ultrasound and MRI of the morphological features of the bilateral seminal vesicles ( SV) and ejaculatory duct ( ED) areas. Criteria for inclusion were haematospermia symptoms that occurred more than six times, that lasted more than 6 months, and that did not improve after >1 month of conservative treatment. Patients underwent seminal vesiculoscopy with a post-surgery follow-up of 3-48 months [average (18.1 ± 10.3) months]. Of the 102 patients that underwent MRI examination, data from 88 patients (86.3%) showed typical and characteristic changes in the ED area, including the signal intensity changes in 60 (58.8%), SV volume changes in 32(31.4%), the formation of cysts such as prostatic utricular cysts in 27 (26.5%), Müllerian cysts in 4 (3.9%), ED cysts in 5 (4.9%) and a SV cyst in 1(1.0%). The MRI findings were confirmed by seminal vesiculoscopy and all patients received appropriate treatment. In 14 patients (13.7%), no obvious abnormal changes were observed with MRIs, however, these patients were diagnosed and successfully managed using seminal vesiculoscopy. Some degrees of ED obstruction was usually found during surgery. The symptoms of haematospermia disappeared 1-2 months after surgery in all patients. Two patients had a recurrence of haematospermia, underwent the same treatment, and recovered during the follow-up period. The aetiology of the most cases of the refractory haematospermia can be distinguished using the three-dimensional MRI. Typical abnormalities observed on MR images are signal intensity, SV volume changes and cyst formation. MRI has significant etiological diagnostic value and provides reliable information for the subsequent treatment of patients with persistent and refractory haematospermia. [ABSTRACT FROM AUTHOR]

. Portal hypertension and splenomegaly are common in patients with cirrhosis. However, there is limited previous in vivo research on the correlation between spleen stiffness and stages of liver fibrosis. This study aimed to evaluate the diagnostic value of spleen stiffness measurement (SSM), using acoustic radiation force impulse (ARFI) technology, for liver fibrosis assessment. Eligible patients with chronic hepatitis B or C ( n = 163) underwent concurrent liver stiffness measurement (LSM), SSM and percutaneous liver biopsy. Receiver operating characteristic curves estimated the diagnostic performance of SSM, with multiple linear regression models for LSM and SSM determining the significance of explanatory factors. Results indicated significant correlation between LSM and SSM ( R2 = 0.574, P < 0.0001). Using SSM to classify METAVIR fibrosis (METAVIR F) scores, the areas under curves were 0.839 (95% CI: 0.780-0.898) for METAVIR F1 vs F2-4, 0.936 (95% CI: 0.898-0.975) for F1-2 vs F3-4 and 0.932 (95% CI: 0.893-0.971) for F1-3 vs F4, all P < 0.001. Multiple linear regression models identified BMI, spleen stiffness, METAVIR F3 and F4, serum alanine aminotransferase, international normalized ratio of prothrombin time, sodium and platelet count as significant independent explanatory factors for liver stiffness (adjusted R2 = 0.724, P < 0.001). Male gender, liver stiffness, METAVIR F2, F3 and F4 also significantly and independently explained spleen stiffness (adjusted R2 = 0.647, P < 0.001). ARFI SSM is potentially useful as a single or adjunct predictor of stages of liver fibrosis. [ABSTRACT FROM AUTHOR]

Summary Background The roles remain unclear of early on-treatment quantitative serum HBsAg and hepatitis B virus (HBV) DNA levels in the prediction of a sustained response (SR) to peginterferon alfa-2a therapy in HBeAg-negative chronic hepatitis B (CHB) patients infected with genotype B or C. Aims To determine their roles in HBeAg-negative CHB patients infected with genotype B or C. Methods Sixty-one patients were treated with peginterferon alfa-2a for 48 weeks. Serum HBsAg levels were quantified using the Abbott Architect HBsAg QT assay throughout treatment. Multiple regression analyses were performed to identify independent predictors of SR. Results Nineteen patients (31%) achieved SR with serum HBV DNA levels <312 copies/mL at 24 weeks post-treatment. Serum HBsAg levels at 12 (OR 31.9; 95% CI 4.8-209.6; P = 0.0003) and 24 weeks of therapy (OR 8.8; 95% CI 2.0-38.0; P = 0.0035), and HBV DNA levels at baseline (OR 7.0; 95% CI 1.3-36.2; P = 0.0203), 12 (OR 7.9; 95% CI 1.2-48.4; P = 0.0249) and 24 weeks of therapy (OR 22.3; 95% CI 2.2-224.0; P = 0.0083) were early independent predictors of SR. A serum HBsAg cut-off of 150 IU/mL at week 12 had an AUC, sensitivity, specificity and positive and negative predictive values of 0.75, 63%, 95%, 86% and 85% with respect to predicting SR respectively. Conclusions A quantitative serum HBsAg level at 12 weeks of therapy can be used for the early prediction of SR to peginterferon therapy in HBeAg-negative CHB patients infected with genotype B or C. [ABSTRACT FROM AUTHOR]

Salidroside, a novel effective adaptogenic drug extracted from the medicinal plant Rhodiola sachalinensis A. Bor, can be derived from phenylalanine or tyrosine. Due to the scarcity of R. sachalinensis and its low yield of salidroside, there is great interest in enhancing production of salidroside by the plant. In this study, a cDNA clone encoding phenylalanine ammonia-lyase (PAL) was isolated from R. sachalinensis using rapid amplification of cDNA ends. The resulting cDNA was designated PALrs1. It is 2407-bp long and encodes 710 deduced amino acid residues. Southern blot analysis of genomic DNA indicated that the PAL gene family is composed of three to five genes in the R. sachalinensis genome. Northern blot analysis revealed that transcripts of PALrs1 were present in calli, leaves and stems, but expression in roots was very low. The PALrs1 under the 35S promoter with double-enhancer sequences from CaMV-Ω and TMV-Ω fragments was transferred into R. sachalinensis via Agrobacterium tumefaciens. PCR and PCR–Southern blot confirmed that the PALrs1 gene had been integrated into the genome of transgenic plants. Northern blot analysis revealed that the PALrs1 gene had been expressed at the transcriptional level. High-performance liquid chromatography indicated that overexpression of the PALrs1 gene resulted in a 3.3-fold increase in p-coumaric acid content, as expected. In contrast, levels of tyrosol and salidroside were 4.7-fold and 7.7-fold, respectively, lower in PALrs1 transgenic plants than in controls. Furthermore, overexpression of the PALrs1 gene resulted in a 2.6-fold decrease in tyrosine content. These data suggest that overexpression of the PALrs1 gene and accumulation of p-coumaric acid did not facilitate tyrosol biosynthesis; tyrosol, as a phenylethanoid derivative, is not derived from phenylalanine; and reduced availability of tyrosine most likely resulted in a large reduction in tyrosol biosynthesis and accumulation of salidroside. [ABSTRACT FROM AUTHOR]

Fragments within S1 genes ( poly100S1) of infectious bronchitis virus (IBV) strains ZJ971, M41 and SC021202 (SC) were subcloned into a prokaryotic expression vector and expressed in Escherichia coli. Monoclonal antibodies (mAbs) against the recombinant poly100S1 proteins were produced, characterized and used to analyse epitopes on the S1 subunit of IBV. Nine mAbs raising from the three poly100S1 proteins recognized five different epitopes of the S1 subunit, designated as S1-A, B, C, D and E. Epitopes S1-C and S1-D are common for the three IBV strains, while S1-A and S1-B exist on ZJ971 and M41 strains, and S1-E was a strain-specific epitope for SC strain. Immunocytochemistry indicated that all the mAbs to the poly100S1 proteins can react with the homologous S1 glycoprotein expressed in Vero cells. Moreover neutralization test demonstrated that only mAbs 6E2, 4F9 and 6G4 had neutralization activity for the homologous IBV. These mAbs to poly100S1 protein were potential candidates for detecting and distinguishing IBV strains, and also used to examine antigenic variation of the S1 protein. [ABSTRACT FROM AUTHOR]

Abstract Aim: There is a characteristic neurohumoral activation in heart failure (HF). However, few studies have been performed to examine the role of the central nervous system in the activation of sympathetic outflow during HF. In this paper we review some of our studies, with particular emphasis on examining the role of the paraventricular nucleus (PVN) in the exaggerated sympathetic outflow commonly observed in HF. Results: Our studies have revealed that the inhibitory mechanisms regulating sympathetic outflow are mediated by nitric oxide (NO) and γ -aminobutyric acid (GABA) within the PVN and are attenuated in HF. These alterations are associated with elevated sympathetic activity. Furthermore, these studies have indicated that the interactions among excitatory (angiotensin II and glutamate) and inhibitory (NO and GABA) neurotransmitters/mediators within the PVN significantly influence sympathetic outflow. Conclusion: Reduced inhibitory actions of NO and/or GABA within the PVN may exaggerate an increase in the actions of excitatory neurotransmitters such as glutamate and angiotensin II within the PVN and this may contribute to the overall sympatho-excitation commonly observed in HF. [ABSTRACT FROM AUTHOR]

The article discusses a research study on evaluating the renal function of dairy cows diagnosed with subclinical ketosis. Observed were venous blood of 55 subclinically affected with ketosis cows and 55 healthy cows in early lactation for the examination of differences in &beta-hydroxybutyrate (BHB), non-esterified fatty acids (NEFA) and total protein (TP). Comparison of results showed that serum BHB and NEFA concentrations in healthy cows are higher significantly than those of cows with subclinical ketosis but with no difference in TP concentrations.

Methylaspartate ammonia lyase (MAL) catalyses the reversible α,β-elimination of ammonia from L-threo-(2S,3S)-3-methylaspartic acid to give mesaconic acid. Crystals of Citrobacter amalonaticus MAL have been obtained by the hanging-drop method of vapour diffusion using ammonium sulfate as the precipitant. Three crystal forms were obtained from identical crystallization conditions, two of which (forms A and B) diffract to high resolution, whilst the third form diffracted poorly. Crystals of form A diffract to beyond 2.1 Å and have been characterized as belonging to one of the enantiomorphic space groups P4122 or P4322, with unit-cell parameters a = b = 66.0, c = 233.1 Å, α = β = γ = 90° and a monomer in the asymmetric unit. Crystals of form B diffract to beyond 1.5 Å and belong to space group C222, with unit-cell parameters a = 128.3, b = 237.4, c = 65.8 A, a = = y = 900 and a dimer in the asymmetric unit. Determination of the structure of MAL will be an important step in resolving current conflicts concerning the enzyme mechanism which differ between one which places MAL as a member of the superfamily of ammonia lyases whose catalytic activity requires a cofactor formed by post-translational modification of the enzyme and another which links MAL to the enolase superfamily. [ABSTRACT FROM AUTHOR]

Vertical atmospheric layering is included in a previously described,zonally averaged global multimedia distribution model. This model isused to simulate the fate of alpha -hexachlorocyclohexane (alpha -HCH), the main ingredient of the technical HCH pesticide mixture, for the 50 years of its large-scale use (1947-1997). Worldwide historic emission estimates are compiled, assigned to 10 climate zones, and usedas input in model calculations. The performance of the model is evaluated by comparing calculated and measured concentrations in the atmosphere and seawater. A major focus is on the arctic and northern temperate environment, and emphasis is also placed on absolute levels, time trends, latitudinal profiles, and air-water exchange. In general, simulated and observed concentrations agree within one order of magnitude. Deviations are explained by the zonal averaging characteristicsof the model and uncertainties associated with the environmental degradation rates of alpha -HCH. In both model results and observations,the dramatic decrease in the global emission of alpha -HCH is reflected in rapidly decreasing concentrations in the atmosphere and seawater, except in the Arctic Ocean, which apparently is the last refuge for alpha -HCH in the global environment. The model thus provides an illustration of the response characteristics of the global system to the reduced emissions of alpha -HCH. Its application to other chemicals with reduced emission is discussed. [ABSTRACT FROM AUTHOR]

A carrier containing primary amine groups was synthesized by the reaction between nitrilon fibre and diethylenetriamine, and papain was immobilized on this kind of carrier by using glutaraldehyde as a coupling agent. The factors involved with the activity recovery of the immobilized papain and the enzymic properties of the resulting immobilized papain were studied in comparison with free papain, for which casein was chosen as a substrate. The results show that the activity recovery of immobilized papain can reach 47.3%, and that the immobilized papain exhibits better environmental adaptability and reusability than free papain.