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A protocol for large-scale propagation of Phragmites communisTrin. by somatic embryogenesis has been established. Plants were regenerated through somatic embryogenesis from stem segments of R5002-12, a salt-tolerant variant line of Phragmites communisTrin. Stem segment explants produced hard white callus on the semi-solid Murashige and Skoog (MS) medium supplemented with 9.05 μM 2,4-dichlorophenoxy acetic acid (2,4-D) for 4 weeks. The induction frequency was 36.7%. Then, the callus was transferred to MS medium supplemented with 4.52 μM 2,4-D. After 4 weeks in culture, yellow embryogenic callus with some nodular structures was formed. When the embryogenic callus was transferred to differentiation medium (MS supplemented with 0.45 μM 2,4-D), differentiation was initiated to form small green islands on the surface of the callus after 2 weeks in culture. Within 4 weeks, a large number of somatic embryos were formed with a frequency of 86.7%. Six weeks later, they developed into strong plantlets. When the plantlets (about 1 cm in length) were cultured on propagation medium (MS supplemented with 13.31 μM BA+5.37 μM NAA), a great number of regenerated plants were obtained. After the plants were cultured on liquid 1/2 MS medium with 2.69 μM NAA added 2.46 μM IBA roots developed. The rooted plants were transferred to soil with over 85% survival. Using this methodology, more than 20000 regenerated plants of salt tolerant variant line of Phragmites communisTrin. have been produced.

The study was designed to define the contribution of cytochrome p450 2C19 (CYP2C19) and cytochrome p450 3A4 (CYP3A4) to citalopram N-demethylation and to evaluate the relationship between the disposition of citalopram and CYP2C19 genotype. A single oral 40-mg dose of citalopram was administered to eight extensive metabolizers and five poor metabolizers recruited from 77 healthy Chinese volunteers whose genotypes and phenotypes were predetermined. The plasma concentrations of citalopram and desmethylcitalopram were determined by high-performance liquid chromatography. It was found that the genotype of CYP2C19 had a significant effect on the N-demethylation of citalopram. Poor metabolizers with m1 mutation had higher area under the plasma concentration versus time curve (AUC0--> infinity ) values than did extensive metabolizers. Terminal elimination half-life (t1/2) values of citalopram in poor metabolizers were significantly higher than the values in extensive metabolizers who were either homozygous or heterozygous with CYP2C19*1. The oral clearance (CLoral) of citalopram in poor metabolizers was significantly lower than that of extensive metabolizers. The AUC0--> infinity and maximum plasma concentration (Cmax) of desmethylcitalopram in poor metabolizers were significantly lower than the values of extensive metabolizers. The results show that CYP3A4 is not the major enzyme in the N-demethylation of citalopram among extensive metabolizers. The polymorphism of CYP2C19 plays an important role in the N- demethylation of citalopram in vivo. The extensive metabolizers and poor metabolizers of CYP2C19 had significant difference in disposition of citalopram in vivo.

Glycosylasparaginase (GA) is an amidase and belongs to a novel family of N-terminal nucleophile hydrolases that use a similar autoproteolytic processing mechanism to generate a mature/active enzyme from a single chain protein precursor. From bacteria to eukaryotes, GAs are conserved in primary sequences, tertiary structures, and activation of amidase activity by intramolecular autoproteolysis. An evolutionarily conserved His-Asp-Thr sequence is cleaved to generate a newly exposed N-terminal threonine, which plays a central role in both autoproteolysis and in its amidase activity. We have recently determined the crystal structure of the bacterial GA precursor at 1.9-A resolution, which reveals a highly distorted and energetically unfavorable conformation at the scissile peptide bond. A mechanism of autoproteolysis via an N-O acyl shift was proposed to relieve these conformational strains. However, it is not understood how the polypeptide chain distortion was generated and preserved during the folding of GA to trigger autoproteolysis. An obstacle to our understanding of GA autoproteolysis is the uncertainty concerning its quaternary structure in solution. Here we have revisited this question and show that GA forms dimers in solution. Mutants with alterations at the dimer interface cannot form dimers and are impaired in the autoproteolytic activation. This suggests that dimerization of GA plays an essential role in autoproteolysis to activate the amidase activity. Comparison of the melting temperatures of GA dimers before and after autoproteolysis suggests two states of dimerization in the process of enzyme maturation. A two-step dimerization mechanism to trigger autoproteolysis is proposed to accommodate the data presented here as well as those in the literature.

It was found that melatonin could be incorporated and accumulated on the surface of the glassy carbon electrode which was activated electrochemically by pretreatment in sodium hydroxide solution by means of cycling the potential well into the positive limit of the solvent. In Britton-Robinson buffer solution (pH 6.7), melatonin gave a sensitive oxidation wave at a potential of +0.65 V (vs.Ag/AgCl) by using Osteryoung square-wave stripping voltammetry (OSWSV). The oxidation process has been shown to be irreversible and adsorption-controlled at this electrode by means of cyclic voltammetry and linear sweep voltammetry. A chronocoulometric characterization of the adsorption characteristics of melatonin at this electrode is also presented. The factors affecting the peak current were optimized, and the dependence of peak currents on the concentration of melatonin was found to be linear in the range 8.0×10⁻⁷−1.0×10⁻⁵ mol L⁻¹. A detection limit of 5.0×10⁻⁸ mol L⁻¹ was obtained (signal-to-noise ratio of 3). This method was applied to the assay of melatonin in tablets and capsules with good recoveries (98–100%).

Most acute promyelocytic leukemia (APL) cases have t(15;17)(q22;q21) chromosomal translocation and PML-RARα chimeric gene which blocks granulocytic differentiation. The introduction of all-trans-retinoic acid (ATRA) and arsenic compounds, especially arsenic trioxide ( As2O3), has provided good models to study not only differentiation and/or apoptosis therapy but also molecular target-based cancer treatment. In vivo and in vitro investigations have shown that both agents are able to induce differentiation of APL cells: ATRA tends to induce terminal differentiation, while low-dose As2O3can induce partial differentiation. Significant progress has been made in understanding the molecular mechanisms of APL pathogenesis and differentiation therapy. Pharmacological concentrations (0.1~1μM) of ATRA derepresses transcription by releasing CoR from, and recruiting CoA to PML-RARα, whereas As2O3triggers a rapid degradation of PML-RARα. In fact, the two drugs act on the same oncoprotein through targeting different moieties and in distinct ways and thereby abrogate its dominant-negative effects on regulatory pathways necessary for granulocytic differentiation. As to apoptosis, it is clear that high-dose As2O3can induce mitochondria-mediated cell death pathway in a thiol-dependent manner, while the mechanism of ATRA-induced apoptosis needs further elucidation. Transcriptomic and proteomic analysis are also expected to find new molecular targets. It is the hope that what we have learnt from APL will benefit further developments of anti-leukemia therapy.

This paper holds that an anti-corruption campaign in the process of modernization in developing countries must be sustained and systematic, and conformed, and geared to the whole modernization drive and be reconciled with economic development, social stability, improvement of efficiency and perfection of the legal system, with safeguarding and promoting the overall development of modernization as its purpose. Based on analysis of the characteristics of corruption among government officials, the present paper puts forward five measures to fight it. Anti-corruption program in a political campaign is of so great importance that proper measures should be taken. The success of this campaign lies largely in the balance between the evil forces behind corruption and the combined force of all the good people in and outside the government, who are behind the anti-corruption campaign. With the spread of corruption, the campaign should not be confined to the government itself; the participation and support, of non-governmental democratic institutions and organizations should be sought.

Some important factors for designing a series hybrid active power filter (SHAPF) are presented in this paper for the case when the load is varied in a wide range and/or the source voltage is seriously distorted. Special design of passive filters, adaptive control of parameter and multi variant control are discussed in detail. The filter is stable, has good performance, and causes small capacitive reactive current. The simulation and experimental results accorded with the theoretical analysis results.

A novel topology for ripple-free input current circuit is put forward in the paper. Compared to traditional EMI (electromagnetic interference) filter consisting of choke and capacitor, the ripple-free topology can reduce the converter's ripple current with the use of smaller component. The new ripple-free topology proposed in this paper does not need elaborate adjustment of the coupling coefficient as required by conventional ripple-free techniques, and is ripple voltage cancellation or isolation mode, which can attenuate the ripple further if the line impedance is considered. The theoretical prediction is confirmed by experimental results.

ABSTRACT

This paper proposes a new structure of serial hybrid active power filter which can reduce the power rating of the active power filter dramatically, and has good performance for harmonic suppression. The principle and designing rules are analyzed. The proposed structure is rational and feasible for high kVA applications. Simulation results are presented too.

In Li-ion batteries, functional cosolvents could significantly improve the specific performance of the electrolyte, for example, the flame retardancy. In case the cosolvent shows strong Li+-coordinating ability, it could adversely influence the electrochemical Li+-intercalation reaction of the electrode. In this work, a noncoordinating functional cosolvent was proposed to enrich the functionality of the electrolyte while avoiding interference with the Li storage process. Hexafluorocyclotriphosphazene, an efficient flame-retardant agent with proper physicochemical properties, was chosen as a cosolvent for preparing functional electrolytes. The nonpolar phosphazene molecules with low electron-donating ability do not coordinate with Li+and thus are excluded from the primary solvation sheath. In graphite-anode-based Li-ion batteries, the phosphazene molecules do not cointercalate with Li+into the graphite lattice during the charging process, which helps to maintain integral anode structure and interface and contributes to stable cycling. The noncoordinating cosolvent was also applied to other types of electrode materials and batteries, paving a new way for high-performance electrochemical energy storage systems with customizable functions.

Glycosylasparaginase (GA) represents a novel group of proteins that are activated by self‐catalyzed peptide‐bond cleavage from a single‐chain precursor to yield the two subunits required for hydrolase activity. The wild‐type GA precursor autoproteolyzes spontaneously into α and β subunits. Strategies are reported here for purification to homogeneity of GA from Flavobacterium meningosepticumin both single‐chain precursor and mature (autoprocessed) forms. The recombinant proteins crystallize in different space groups: P1 and P21for the precursor and mature enzymes, respectively. The precursor crystals diffract to 1.9 Å resolution with laboratory X‐ray radiation.

Abstract:: Relativistic distorted-wave method was used to calculate the electron impact excitation collision strengths for transitions 2 s2 1 S0-2 s 2 p 3 P1 of Be-like isoelectronic ions. The target states were described, respectively, by 10-level, 46-level and 133-level MCDF configuration-expansion. The relativistic continuum orbitals were calculated in the potential field of frozen target-ion charge distribution with semi-classical exchange potential. The influence of the target states on this collision process along the isoelectronic sequence was investigated in the above three MCDF configuration-expansion modes. It was found that the configurations in the n =3 and the n =4 complexes have great influence on both the high and the low Z ions but the influence is relatively small for intermediate Z ions. The latter phenomenon was attributed to competition between opposing correlation and relativistic effects on the collision strengths.

Koro epidemics, characterized by panic due to fear of genital retraction, involving more than 2000 victims, mainly young men, occurred in Hainan Island and Leizhou Peninsula of Guangdong Province, China, in 1984–85 and 1987. A questionnaire survey of 214 victims of these epidemics was conducted in 1988. The survey focused on symptom manifestation, personality profile, life problems, and folk belief. The results of the “koro” group were compared with those of a “clinic” group with minor psychiatric disorder and a “control” group from the non-clinical, non-koro episode population in the epidemic area. The results revealed that the victims of the koro epidemics were characterized by low intellectual endowment and strong acceptance of koro-related folk beliefs. The results support the hypotheses that: a) a koro attack is a psychologically induced anxiety-panic condition; b) the presence of an intensive belief in the culturally related concept of koro makes the subject vulnerable to the attack; and c) social crisis or tension serves as a trigger for the occurrence of the epidemic.

When niechanically polished Ge, Si, GaAs, LiNbOj, Cd-Ga-garnet, fused quartz and glass surfaces are sputtered by low energy ion beam (from 300 to 1200 eV) at an incident angle of 45°, the surfaces are found to exhibit hillock-like features. The influence of ion beam incident angle, energy, dose and target rotation on surface topography have been investigated. The analysesof hillocks by SIMS and AES show that their formation may not be due to impurity contamination caused by redeposition. A mechanism for hillock formation is proposed. This can be expressed by aformula, through which all the results can be successfully explained.

Abstract: In this paper, the uniformly valid asymptotic solutions for the complex equation of the axial symmetrical problems of a/,r2>0 toroidal shells with constant thickness in bending theory are given.

Abstract: According to the classical shell theory based on the Love-Kirchhoff assumptions, the basic differential equations for the axial symmetrical problems of r>0 thin uniform circular toroidal shells in bending are derived, and the second order asymptotic solutions are given for r>0 thin uniform circular toroidal shells with a large parameter a2/R0h. In the resent paper, the second order asymptotic solutions of the edge problems far from the apex of toroidal shells are given, too. Their errors are within the margins allowed in the classical theory based on the Love-Kirchhoff assumptions.

The crystal structures of class I major histocompatibility complex (MHC) molecules complexed with antigenic peptides revealed a network of hydrogen bonds between the charged amino‐ and carboxyl‐termini of the peptides and conserved MHC residues at both ends of the peptide binding site. These interactions were shown to contribute substantially to the stability of class I MHC/peptide complexes by thermal denaturation studies using synthetic peptides in which either the amino‐ or carboxyl‐terminal group is substituted by a methyl group. Here we report crystal structures of HLA‐A*0201 complexed with these terminally modified synthetic peptides showing that they adopt the same bound conformation as antigenic peptides. A number of variations in peptide conformation were observed for the terminally modified peptides, including in one case, a large conformational difference in four central peptide residues that is apparently caused by the lattice contact. This is reminiscent of the way binding a T‐cell receptor changed the conformation of central residues of an MHC‐bound peptide. The structures determined identify which conserved hydrogen bonds are eliminated in terminally substituted peptides and suggest an increased energetic importance of the interactions at the peptide termini for MHC‐peptide stability. Proteins 33:97–106, 1998. © 1998 Wiley‐Liss, Inc.

Cross sections for excitation induced by electron collision between low-lying 1s22s22p5and 1s22s2p6states of F-like selenium and from these states to singly excited states with the excited electron occupying theMshell have been calculated by relativistic distorted-wave Born procedures. The GRASP2code was used for the atomic structure calculations. The continuum orbitals for the construction of continuum states were computed in the distorted-wave approximation, in which the distorted-wave potential used was the spherically averaged potential of the nucleus plus the potential of the bound electrons of the bound state. The cross sections for excitations were computed first by a 133-level multiconfiguration Dirac–Fock (MCDF) configuration expansion and then by a 279-level MCDF configuration expansion. The latter procedure, which also took into account contributions from all the participating singly excitedN-shell states, was found to be necessary for improved accuracy. The cross section data should be a useful reference in the development of x-ray lasers and other related fields involving highly stripped ions.

Abstract: By using calcium ion selective electrode (Ca ISE) as indicating electrode, saturated calomel electrode (SCE) as reference electrode and EGTA as titrant, calcium in seawater was determined by potentiometric titration in borate buffer solution. This method can reduce observation errors in the determination of the endpoint, and thus provide better analytical precision (<0.08%) than present complexometric titration.

The densities of 36 water samples from the Huanghe River estuary and Bohai Bay were determined by a magnetic float densimeter under three temperatures from 15°C to 25°C. All the measured densities of samples were greater than that of the values calculated from the International Equation of State of Seawater. The differences between the measured and calculated densities increased with the decrease of salinities. The differences appeared exponentially correlated with [Ca2+]/s, [Mg2+]/s and [SO42−]/s, and had “s” type curve relationship with the alkalinity in all salinity range. But in the salinity ranging from 25.72 to 31.57, the relationships were all linear. The density difference can be estimated from the equation Δρ(103kg · m−3). It was the high alkalinity and [Ca2+]/s that resulted in the measured densities of seawaters being higher than the calculated densities in the Huanghe estuary and Bohai Bay.

Glycosylasparaginase (GA) is a member of a novel family of N-terminal nucleophile hydrolases that catalytically use an N-terminal residue as both a polarizing base and a nucleophile. These enzymes are activated from a single chain precursor by intramolecular autoproteolysis to yield the N-terminal nucleophile. A deficiency of GA results in the human genetic disorder known as aspartylglycosaminuria. In this study, we report the crystal structure of recombinant GA fromFlavobacterium meningosepticum. Similar to the human structure, the bacterial GA forms an αββα sandwich. However, some significant differences are observed between theFlavobacteriumand human structures. The active site ofFlavobacteriumglycosylasparaginase is in an open conformation when compared with the human structure. We also describe the structure of a mutant wherein the N-terminal nucleophile Thr152is substituted by a cysteine. In the bacterial GA crystals, we observe a heterotetrameric structure similar to that found in the human structure, as well as that observed in solution for eukaryotic glycosylasparaginases. The results confirm the suitability of the bacterial enzyme as a model to study the consequences of mutations in aspartylglycosaminuria patients. They also suggest that further studies are necessary to understand the detail mechanism of this enzyme. The presence of the heterotetrameric structure in the crystals is significant because dimerization of precursors has been suggested in the human enzyme to be a prerequisite to trigger autoproteolysis.

The relativistic distorted-wave method was used to calculate electron impact excitation of B+. The target states were described by a 133-level MCDF configuration-expansion. The relativistic continuum orbitals were calculated in the potential field of the frozen target-ion charge distribution. The semiclassical and free-electron-gas approximations of Riley and Truhlar and the Dirac–Fock–Slater (DFS) approximation were used in the calculation of exchange distortion potentials. It is found that the exchange potentials have significant influence on collision strengths especially for spin-forbidden transitions. In particular, DFS potentials are less suitable compared with the other potentials.

In this single-center, randomized, open-label, 3-way crossover study, subjects received each of the following: a single dose of Tramadol Hydrochloride Injection (THI) 35 mg, a single dose of Promethazine Hydrochloride Injection (PHI) 45 mg, and single dose of Compound Tramadol Hydrochloride Injection (CTHI) 80mg. Blood was collected and plasma was analyzed for the pharmacokinetic parameters (maximum plasma concentration [Cmax], time to Cmax [Tmax], area under the plasma concentration-time curve, plasma elimination half-life, clearance, and apparent volume of distribution) of Tramadol and Promethazine. In general, several pharmacokinetic interactions were observed between Tramadol and Promethazine in the present study.

Insulin-regulated aminopeptidase (IRAP) in humans is a membrane bound enzyme that has multiple functions. It was first described as a companion protein of the insulin-responsive glucose transporter, Glut4, in specialized vesicles. The protein has subsequently been shown to be identical to the oxytocinase/aminopeptidase or the angiotensin IV (Ang IV) receptor (AT4receptor). Some AT4ligand peptides, such as Ang IV and LVV-hemorphin-7, have been shown to act as IRAP inhibitors that exert memory-enhancing properties. As such IRAP has been a target for developing cognitive enhancers. To facilitate detailed mechanistic studies of IRAP catalysis and inhibition, and to pave the way for biophysical and structural studies of IRAP in complex with peptide inhibitors, we report here an optimizedexpression and purification system using High Five insect cells. We also report biochemical characterizations of the purified recombinant IRAP with a standard aminopeptidase substrate and an optimized IRAP peptide inhibitor with a Ki of 98 nM.

To observe the clinical therapeutic effect of diabetic peripheral neuropathy (DPN) treated by needling combined with drug, 104 patients with DPN were randomly divided into acupuncture plus drug group and control group, and each group had 52 patients. After treatment of two months, the clinical effective rate in acupuncture plus drug group was 51.9%, and the total effective rate was 88.5%, both of them were better than those in control group (P<0.05). The needling method of nourishing the kidney and dredging the meridian combined with drug had good clinic effect in the treatment of DPN.

PurposeTo observe the effect of acupuncturing different points on unstable bladder.MethodFifty-one patients of unstable bladder were divided randomly into Shu-point group, Mu-point group, He-point group, observe the change of symptom score and urodynamics.ResultsPuncturing these points can improve the symptom score and urodynamics, but the different points can get different effect, and the effect of Shu-point and He-point is superior to that of Mu-point.ConclusionThe different points of bladder have different adjusting function and that function relates with nerves locating in points.

PurposeTo observe the curative effect of special acupuncture techniques on female urethral syndrome and its relationship with the course of treatment.MethodFour abdominal and four sacral empirical points were acupunctured with special techniques and electricity. A difference in curative effect was investigated between different numbers of treatments.ResultsThe clinical cure rate reached 15.2% just after ≤10 (7.3±1.3) treatments. The curative effect was significantly better after 20–40 (32.1±5.8) treatments than after ≤10 (7.3±1.3) treatments ({ie19-1},P<0.05). The clinical cure rate reached 43.5% in the former.ConclusionSpecial acupuncture techniques have a good clinical effect on female urethral syndrome. The curative effect improves with an increase in the number of treatments.

Three hundred and seventeen cases of facial paralysis were treated by acupuncture plus acupoint-injection, the results showed 313 cases were cured, 3 cases got significant effect and 1 case had effect, and the total effective rate was 100%. This method is perfect for treatment of facial paralysis and worthy of popularization.

The article presents a study which examines the difficulty in establishing a high level sports team in a particular university in China. It explores the extant condition of the sports team as well as the different factors that stimulate this condition including the ideological recognition, lack of athletes, and trainer. It projects that the issue will be addressed through students' recruitment initiative, financial support, increasing the competition opportunity and trainers' capacity level.