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A novel kind of chiral phosphine-oxazoline ligands 3 with an axial-unfixed biphenyl backbone bearing different substituent on oxazoline ring and P phenyl ring was prepared. These ligands exist as a mixture of two diastereomers in equilibrium in solution. Upon coordinated to Pd(II), however, only one of the two possible kinds of diastereomer complexes with different axial chirality was formed. These compounds as chiral ligands were applied in Pd-catalyzed asymmetric allylic alkylation with high reaction activity and enantioselectivity. Meanwhile, the asymmetric catalytic behavior was affected obviously by the substituent at oxazoline ring and P phenyl ring. The best result, up to 92.3% ee and 99% yield, was obtained with the ligand 3c having two phenyl groups on P and a phenyl group on oxazoline ring in this asymmetric catalysis reaction.

The definitive version is available at www.blackwell-synergy.com., Article, JOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY. 20(11): 1726-1730 (2005)

A time-discontinuous Galerkin finite element method (DGFEM) for dynamics and wave propagation in non-linear solids and saturated porous media is presented. The main distinct characteristic of the proposed DGFEM is that the specific P3–P1 interpolation approximation, which uses piecewise cubic (Hermite's polynomial) and linear interpolations for both displacements and velocities, in the time domain is particularly proposed. Consequently, continuity of the displacement vector at each discrete time instant is exactly ensured, whereas discontinuity of the velocity vector at the discrete time levels still remains. The computational cost is then obviously saved, particularly in the materially non-linear problems, as compared with that required for the existing DGFEM. Both the implicit and explicit algorithms are developed to solve the derived formulations for linear and materially non-linear problems. Numerical results illustrate good performance of the present method in eliminating spurious numerical oscillations and in providing much more accurate solutions over the traditional Galerkin finite element method using the Newmark algorithm in the time domain. Copyright © 2003 John Wiley & Sons, Ltd.

The emergence and spread of bacteria carrying the bla NDM-1 gene has become a worldwide concern. Here, we report eight cases of Klebsiella pneumoniae with bla NDM-1 in the neonatal ward of a teaching hospital in mainland China. Multilocus sequence typing showed that seven isolates were clonally related and confirmed them as sequence type 17 (ST17). One isolate belonged to ST433. These findings suggest continuous spread of bla NDM-1 in mainland China and emphasize the need for intensive surveillance and precautions.

Brucellosis is far more frequent in a pasturing area in the northern part of our country and it has many clinical manifestations. It may cause multiple organ damage and its features lack specificity. It is rare in the south, so it is extremely easy to be misdiagnosed or overlooked. The retrospective analysis of a case with Brucellosis misdiagnosed as osteoarthrosis provides a guide for clinical doctors to understand Brucellosis, so that early diagnosis would be accessible, and prognosis could be improved.

HAuCl4 was reduced by sodium citrate to prepare 10 nm gold nanoparticles (AuNPs) that were modified by the bisphenol A aptamer (Apt) to obtain an aptamer-nanogold probe (Apt-AuNP) for bisphenol A (BPA). The probes were aggregated nonspecifically to form large clusters, which showed a strong resonance light scattering (RLS) peak at 520 nm, under preparation conditions (pH 7.6 Na2HPO4-NaH2PO4 buffer and ultrasonication). Upon addition of BPA, the probe reacted specifically to form dispersed BPA-Apt-AuNP conjugates that exhibited strong catalysis of the two particle reactions of glucose-Cu(II) and hydrazine hydrochloride-Cu(II) with a strong RLS peak at 360 nm and 510 nm respectively. When the BPA concentration increased, the RLS intensity at 360 nm and 510 nm increased respectively. Accordingly, two new and highly-sensitive RLS methods were established for the detection of BPA, using the Apt-AuNP catalytic amplification.

The title reaction provides an efficient access to chiral C3-mono substituted oxindoles with excellent conversion and up to 93% e.e.

Focal adhesion kinase (FAK) plays an essential role in the activation of hepatic stellate cells (HSC). The role of FAK on proliferation and apoptosis of fibronectin (FN)-stimulated HSC was investigated using short hairpin RNA (shRNA)-mediated gene silencing technology. FAK shRNA decreased the expressions of FAK, p-FAK (Tyr(397)), ERK(1), and p-ERK(1). FAK gene silencing also inhibited HSC proliferation by 11.08% at 12-h, 15.12% at 24-h, and 28.62% at 48-h post-transfection. Flow cytometric analysis (FACS) revealed that the apoptotic rate at 24 h was increased in the FAK shRNA plasmid group compared with the HK group (8.29 ± 0.79% vs 2.70 ± 0.31%, p0.01). TUNEL also confirmed the increase in the rate of apoptosis (19.00 ± 0.92% vs 7.63 ± 0.70%, p0.01), and studies showed that the caspase-3 expression was increased while the ratio of Bcl-2 to Bax was decreased. Together, these data show that FAK regulates HSC proliferation and induces the apoptosis of HSC via the caspase-3 and Bcl-2/Bax pathway.

By using the iridium complex of a phosphine-oxazoline ligand with an axis-unfixed biphenyl backbone, a highly enantioselective hydrogenation of the C=C bond of exocyclic α,β-unsaturated carbonyl compounds to afford α-chiral cyclic ketones, lactones and lactams was developed.

This paper studies and analyses the problems and deficiencies that are faced by clustering algorithm which is based on hierarchical scene tree, and proposes a clustering algorithm that is based on the best-first search strategy. The algorithm reduces the false-matching rate, and also alleviates the problem of network congestion to some extent, by designing a novel cost function. Both theoretical analysis and experiment reveal that the method of clustering based on best-first search strategy has better data processing capability, and it is more suitable for the application of large-scale virtual environments comparing to the original algorithm based on hierarchy scene tree.

To determine the relation between resistance of hypermutable Pseudomonas aeruginosa and beta-lactamases produced.The bacteria cultured were identified with API 20NE system. Susceptibilities of the bacteria were detected by disk diffusion method. The hypermutable strains were tested with broth dilution assays. The beta-lactamases produced by these strains were characterized by 3-dimensional test and 2-mercaptopropanoic acid inhibited assays.Altogether 120 strains were analyzed and 45 (37.5%) trains were hypermutable.The resistant rates of hypermutable strains were close to or above 60.0% for imipenem, meropenem, cefoperazone/sulbactam, piperacillin/ tazobactam, ceftazidime, cephfime, aztreonam, amikacin and ciprofloxacin.The 3-dimensional test showed that 18 (40.0%) strains produced extended spectrum beta-lactamases (ESBLs), 25 (55.6%) strains produced AmpC enzymes, and 6 (13.3%) strains produced metallo-beta-lactamases.The resistant rates of hypermutablce strains of Pseudomonas aeruginosa to routine antibiotics are high, which is one of the most important reasons for multi-drug resistance that the hypermutable strains produced ESBLs, AmpC enzymes, and metallo-beta-lactamases.

To investigate the association between catecholamine-beta-adrenoceptor (beta-AR)-adenosine 3', 5'-monophosphate (cAMP) system and long-term prognosis in patients with chronic heart failure (CHF).The study population comprised 73 patients with CHF (EF: 23% +/- 10%) with a mean follow-up of 3.8 +/- 1.9 years. Plasma levels of norepinephrine (NE) were measured using high performance lipid chromatography, beta-adrenergic receptor density (Bmax) and the content of cAMP in peripheral lymphocytes were calculated using 3H-dihydroalpneolo as ligand and competitive immunoassay, respectively. Deaths due to cardiovascular events within the follow-up period were registered.The total mortality was 64.7%, 57.4% of which was for cardiogenic (worsening heart failure: 32.4%; sudden death: 25.0%). In the cardiogenic death group, plasma levels of NE and epinephrine (E) (3.74 nmol/L +/- 0.09 nmol/L and 3.17 nmol/L +/- 1.0 nmol/L) and the contents of peripheral lymphocyte cAMP (3.64 pmol/mg protein +/- 1.4 pmol/mg protein) were significantly increased as compared with the survival group (2.68 nmol/L +/- 0.07 nmol/L, 2.41 nmol/L +/- 0.24 nmol/L and 2.73 pmol/mg protein +/- 0.9 pmol/mg protein, respectively, all P0.01). In the sudden death group, plasma levels of NE and E (5.01 nmol/L +/- 0.06 nmol/L and 4.13 nmol/L +/- 0.08 nmol/L) were significantly increased as compared with the worsening heart failure group (2.49 nmol/L +/- 0.07 nmol/L and 2.33 nmol/L +/- 0.8 nmol/L, all P0.001) and to the survival group (2.68 nmol/L +/- 0.07 nmol/L and 2.41 nmol/L +/- 0.14 nmol/L, all P0.01). The incidences of sudden death were 0%, 75%, and 100% (chi(2) = 16.018, P0.01) in patients with plasma NE2.5 nmol/L, NE 2.5 nmol/L - 4.5 nmol/L, and NE4.5 nmol/L, respectively. In the worsening heart failure group, the content of peripheral lymphocyte cAMP (4.46 pmol/mg protein +/- 0.18 pmol/mg protein) was significantly increased compared with the sudden death group (2.39 pmol/mg protein +/- 0.9 pmol/mg protein, P0.001) and to the survival group (2.73 pmol/mg protein +/- 1.1 pmol/mg protein, P0.001). The worsening heart failure death occurences were 5.0%, 72.2%, and 100% (chi(2) = 14.26, P0.01) in patients with a content of peripheral lymphocyte cAMP2.5 nmol/L, cAMP 2.5 nmol/L - 4.5 nmol/L, and cAMP4.5 nmol/L, respectively. Bmax in peripheral lymphocyte was not significantly different (P0.05) among the sudden death, worsening heart failure, and survival groups in CHF patients.Plasma levels of catecholamine increase significantly, and Bmax and the contents of cAMP in peripheral lymphocytes decrease significantly in patients with CHF. High plasma catecholamine levels may be associated with sudden death, and high intralymphocyte cAMP content may be associated with worsening heart failure in CHF patients.

To investigate the effects of ET-1 on isolated perfused rat liver and vascular rings at early and late stages of cirrhosis.Liver cirrhosis was induced by an intraperitoneal injection of 50% CCl(4) (0.3 ml/100 g, twice a week). In the 9th and 14th weekend after injecting CCl(4), the isolated perfused liver and vascular rings were performed to evaluate effects of four concentrations of ET-1 on early and late stages of cirrhosis.The Ppv of L-HC group at baseline was higher than that of E-HC group, both were higher than that of the controls. However, there showed no differences on Phv in these groups. With the concentration of ET-1 increasing, PVP was elevated accordingly in E-HC and L-HC group. L-HC group showed higher PVP compared with E-HC group, both were higher than the controls. While in isolated vascular rings, with the deteriorating of cirrhosis, the cumulative response curves showed right-shift. 0.1 nmol/L ET-1 showed mild relaxation on vascular rings in L-HC group.ET-1 can increase the PVP, especially with the deterioration of cirrhosis, there showed higher reaction compared with normal controls. The vascular rings showed low response on the contrary. So ET-1 plays an important role in the pathogenesis of portal hypertension. In view of its different roles on liver and vascular rings at early and late stages, administration of different selective antagonist of ET receptor at different stages of cirrhosis should be well considered.

Based on the catalytic effect of the bisphenol A aptamer-modified gold nanoparticle (Apt–GN) on the HAuCl4-vitamin C (VC) particle reaction and its resonance Rayleigh scattering effect at 370 nm, 3.33–333.3 ng mL−1 bisphenol A was detected, with a detection limit of 0.083 ng mL−1.

In the presence of sodium citrate as stabilizer, a gold-platinum nanoalloy (GP) in the mole ratio of 49∶1 was prepared by using NaBH4 as a reducing agent. The rabbit anti-human chorionic gonadotrophin antibody (RhCG) was labeled by the GP to obtain a stable immune GP probe (GP-RhCG) for the human chorionic gonadotrophin (hCG). In a pH 5.8 NaH2PO4-citric acid buffer solution and in the presence of KCl, the GP-RhCG probe was aggregated un-specifically to big particles that exhibited a resonance scattering (RS) peak at 590 nm. When the hCG was added, the GP-RhCG probe com- bined specifically with the hCG to form a dispersed GP-RhCG-hCG immunocomplex that resulted in the RS intensity de- creasing at 590 nm. The decreased RS intensity (ΔI590 nm) is linear with hCG concentration in the range of 6.67—86.7 ng/mL, with a detection limit of 3.7 ng/mL hCG. The immunocomplex exhibited a strong catalytic effect on the slow Cu2O particle reaction of glucose-Cu(II), and the particles appeared a RS peak at 610 nm. When the hCG concentration increased in the immune reaction system, the immunocomplex concentration increased, and the catalytic product of Cu2O particles increased, which caused the enhancement of RS intensity at 610 nm. The increased intensity (ΔI610 nm) is linear with the hCG concentra- tion in the range of 3.33—133 ng/mL, with a detection limit of 1.7 ng/mL hCG. In addition, the influence of foreign sub- stances on the determination of hCG was examined. The results show that 150 times of L-aspartic acid, urea, BSA, glycine, Ca(II) and Zn(II), 50 times of L-lysine and L-cysteine, 30 times of IgG and IgA, 40 times of IgM did not interfered with the determination of 80 ng/mL hCG. This indicates that this method has good selectivity. The hCG content in the serum sample was analyzed by the GP RS method and GP-catalytic RS method, the results are agreement with those of the chemilumines- cence experiments. Both RS methods are of some advantages including low-cost, simplicity, rapidity, high sensitivity and selectivity.