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Using five-laser resonance excitation, we observe the p Rydberg series with n from 39 to 92. The energy levels calculated using the self-consistent-field method and quantum defect theory are in good agreement with the experimental results.

How to design and implement the effective vibration on-line monitoring system is the key problem to carry out the condition monitoring of power transformer for its safe and stable operation. When considered the feasibility and sensitivity of vibration analysis method to monitor the operation condition of power transformer, vibration on-line monitoring system is designed and implemented based on LabVIEW/CompactRIO hardware platform of NI company, according to the actual construction requirements of condition monitoring system of transmission and transformation equipments. The transmission module based on IEC61850 is developed to transmit the voltage, current and vibration signal to the condition evaluation center far away from the power transformer. The developed system has been put into practice on a 500kV power transformer in China and has operated well for about half a year, which is of great guiding significance to the larger application of on-line vibration monitoring system of power transformer.

The authors describe the investigation of the autoionizing states of lutetium atoms by exciting the states 2D3/2o, 2D5/2o, 4D3/2o and 4D5/2o with tunable dye lasers by means of a resonance ionization time-of-flight mass spectrometer. Twenty eight autoionizing transitions were measured and 12 autoionizing states were found. Their Shore-Fano profile parameters were determined by a nonlinear fitting program. The ionization probability for different schemes and some ionization cross sections were compared. On the basis of this, the authors have given the optimal schemes of lutetium atom photoionization through autoionizing states. In addition, the relation between ion signal and the laser pulse energy was discussed.

To study the molecular mechanism of aloe-emodin (AE) in inhibiting smooth muscle cells' (SMC) proliferation.Deendothelialization was performed in abdominal aorta of Japanese white ear rabbits by using 3F Fogarty arterial embolectomy catheter. The media of abdominal aorta was isolated 48 hrs later for performing primary SMC culture. Cells were synchronized with G0/G1 phase by serum starvation, the AE was then added to the culture medium of experimental group, at a concentration of 20 micrograms/ml, and to the control group, equal volume of culture solution was added instead. The c-myc mRNA and protein expressions were examined 3 hrs later by using techniques of Northern blotting, Western blotting and immunocytochemistry respectively.In comparing with the control group, neither the expression of c-myc mRNA nor the expression of c-myc protein was changed after addition of AE.The inhibition of AE on SMC might not be due to influencing c-myc expression, but via other pathway.

The VH and VL genes from a hybridoma cell line producing mouse McAb against alpha-toxin of Clostridium perfringens type A were amplified by RT-PCR. The VH and VL genes were connected thought a flexible linker (Gly4Ser)3 and the VH-linker-VL (ScFv) gene was cloned into a vector pGEM-T. The ScFv gene consists of 726 bp encoding 242 amino acid residues. Both VH and VL genes were confirmed as functionally rearranged mouse immunoglobulin variable region. According to kabat classed method, the VH and VL gene segments belong to mouse Ig heavy chain subgroup II (B) and kappa light chain subgroup III respectively. The ScFv gene was amplified inserted the expression vector pHOG21 and transformed into E coli XL1-BLUE. The ScFv protein was highly expressed in recombinant strain XL1-BLUE (pHOG-2E3) and the expression level of the ScFv was about 25% of total bacteria protein by SDS-PAGE. The neutralization assay showed that the expressed ScFv protein could neutralize the phospholipase C activities of alpha-toxin.

Endothelin-1 (ET-1), a 21 amino acid peptide exerts a wide range of biological activities including vasoconstriction, mitogenesis and inotropic effects on the heart. In this study, we examined whether endocardial endothelial cells express ET-1 and evaluated its functional properties. Using immunofluorescence localization method, we demonstrated cytoplasmic staining of ET-1 in the human endocardial endothelial cells from the right atrium and left ventricle. Employing reverse transcriptase polymerase chain reaction (RT-PCR) expression of ET-1 mRNA and its receptors ET(A) and ET(B) mRNAs were found in human myocardial as well as in endocardial endothelial cells. Biological activity of endocardial endothelial cells derived ET-1 was established as the conditioned media obtained from cultured porcine endocardial endothelial cells induced a slowly developing, strong and long-lasting contraction of circular rat aortic segments, with similar characteristics to that obtained with exogenous ET-1. Furthermore, the selective endothelin-A receptor antagonist, FR 139317, blocked the conditioned media induced contractions. Our results suggest that endocardial endothelial cells express and release biologically active ET-1 which could play a pivotal role in the regulation of myocardial contractility as well as a circulatory peptide may further act in other peripheral target organs.

High-performance carbon nanotubes-supported Pt catalysts ( Pt /CNTs) catalysts were prepared on the basis of Pt precursors reduced by hydrogen plasma ( Pt /CNTs-HP) generated by microwave. The other two Pt /CNTs catalysts prepared by hydrogen ( Pt /CNTs- H ) and NaBH 4 ( Pt /CNTs- N ) reduction were also involved for comparison. The practical composition of the catalysts was characterized with energy dispersive analysis of X-ray (EDAX). It was shown from transmission electron microscopy (TEM) and X-ray diffraction (XRD) that the Pt nanoparticles in Pt /CNTs-HP were uniformly dispersed on CNTs with smaller particle size around 2 nm and narrower size distribution as compared with the other two catalysts. Additionally, X-ray photoelectron spectrum (XPS) analysis indicated higher amount of zero-valence states of Pt in Pt /CNTs-HP caused by hydrogen plasma treatment. The electrooxidation of liquid methanol on these catalysts was investigated by cyclic voltammetry (CV), linear sweep voltammetry (LSV) and chronoamperometry. The long-time durability is very comparable to all the three catalysts. Remarkably, the Pt /CNTs-HP possessed the highest electrocatalytic activity, suggesting that the hydrogen plasma reduction approach can be a promising reduction method for preparing high-performance Pt -based electrocatalysts.

The highly excited states of Lanthanum are studied by means of laser resonance ionization time-of-flight spectrometer. Based on the two-step laser resonance excitation with intermediate state 5d2(3F)6p 2D5/20, three new Rydberg state (RS) series (5d2(a3F2)ns, 5d2(a3F3)nd and 5d2(a1D2)ns) and a number of autoionizing states (AIS) are obtained. Theoretical calculation leads the quantum defects of ns and nd series to the value δs=4.35 and δd=2.80 respectively, which are very close to the experimental results. The Rydberg state series 5d2(a3F2)ns gives the first ionization limit to be 44979.8±0.3 cm−1, which is an order more accurate than ever.

Using five dye lasers excitation, the Yb+ Rydberg series of np1/2, np3/2 have been achieved. And abnormal branching ratios of np1/2:np3/2 excited from Yb+ 7s1/2 are found. In the relativistic central-field independent-particle approximation, oscillator-strength distributions of Yb+ are calculated. The calculated results are in good agreement with our experiment on Yb+. We have found that the abnormal branching ratios are owing to the appearance of Cooper minima.

We have studied the autoionization distribution of penetrating double Rydberg (DR) states NLnl(N

We report here the first study of the Yb double‐Rydberg states based on a new time‐of‐flight mass spectroscopy system with five‐lasers resonance excitation. The first quantitative measurement of relative excitation strength for various core states was worked out. The atomic Rydberg states, the autoionizing Rydberg states and ionic Rydberg states were also investigated.

Glutathione transferases play an important role in the detoxification of many different endogeneous and exogenous compounds such as metabolites of polycyclic aromatic hydrocarbons (PAH) of cigarette tar. There is evidence that PAH may be atherogenic. The glutathione transferase activity towards trans-stilbene oxide (GST-tSBO) can be separated in blood in GST-positive and GST-negative phenotypes. We have previously suggested that the GST-negative phenotype may be associated with a higher morbidity in intermittent claudication among middle aged smokers. In the present study, GST-tSBO could easily be measured in human, rabbit and bovine arterial smooth muscle cells (SMC) in culture. The level of GST-tSBO was higher in rabbit than in bovine SMC. It was stable in bovine SMC during 5 cell passages and it could be induced twofold by long-time incubation with dimethylsulfoxide-soluble particulate matter from cigarette smoke or 3,4-benzo(a)pyrene. There was a positive correlation between the level of GST-tSBO in blood and in "healthy" arterial and venous tissue from individuals operated with coronary bypass. The enzyme levels in arterial tissue were lower than in venous tissue. GST-tSBO in atherosclerotic segments of human arteries was lower than in "healthy" segments from the same artery. These findings suggest that the arterial wall may have a low defense against toxic compounds that may decrease further as atherosclerosis proceeds. It is concluded that SMC are suitable for the study of the effects of PAH in relation to GST-tSBO and that the enzyme activity in blood will reflect the individual GST-tSBO phenotype also in vascular tissues.

The excimer-laser (XeC1) operating at 308 nm, ablates by means of photochemical mechanisms with minimal thermal injury. Two male patients, 53 years and 67 years, with symptomatic peripheral vascular disease underwent percutaneous transluminal excimer-laser angioplasty (PTPELA). Both of them experienced claudication at a short walking distance and had superficial femoral or initial segmental femoral occlusions from 4 cm to 7 cm in length. The laser emitted 120ns pulses at 20 Hz with delivering 16-18 mJ by 7F and 9F catheter, energy density was about 4mJ/mm. The irradiation time was 157 seconds and 185 seconds respectively. Successful recanalization occurred in our two cases, the residual stenosis were less than 20%. The acute outcome was good without any complications.

The specific IgA antibody responses to the protective recombinant Schistosoma mansoni 28-kDa glutathione-S-transferase (Sm28GST) Ag and to derived synthetic peptides have been evaluated before and 6 mo after chemotherapy in S. mansoni-infected patients from Kenya. These studies revealed a parallelism between the age-dependent evolution of IgA antibody levels to Sm28GST and to one synthetic peptide (115-131) and the acquisition of resistance to reinfection. Functional analysis revealed that IgA antibodies to Sm28GST displayed a potent neutralizing effect on the enzymatic properties of the molecule, and also markedly impaired schistosome fecundity, by limiting both the egg laying of mature worms and the hatching capacity of schistosome eggs into viable miracidia. These results suggest that, in addition to IgE, IgA antibodies might participate in the protective immune response against schistosomiasis.

The hypothesis that cells of the arterial wall might modify the consequences of arterial injury was tested. Bovine aortic endothelial cells (EC) or smooth muscle cells (SMC) were exposed to the two toxic stimuli 3,4-benzo(a)pyrene (BP) and dimethylsulfoxide-soluble particulate matter from cigarette smoke (DSP) or factors released from platelets. The modification of the injury caused by these substances on arterial cells was studied by using a conditioned medium from arterial cells or an EC-SMC co-culture model. Direct addition of BP or DSP to the EC or SMC cultures induced toxic effects on the cells. DSP caused a decreased release of prostacyclin by EC. Conditioned medium from EC and SMC modified these toxic effects, which resulted in a reduced cell death and a further decreased cell proliferation, while conditioned medium from SMC increased the release of prostacyclin by EC injured by DSP. In EC-SMC co-culture the same modifications were obtained. The modification of cell injury was not linked to cell proliferation but instead the results suggested that the effects were mediated by multiple substances released from arterial cells. It is concluded that interactions between different cells in the arterial wall, in the non-injured as well as in the injured state, could be modified by endogeneous substances. This might be of relevance for atherogenesis.

The release of prostacyclin by endothelial cells (EC) in culture was studied after exposure to two toxic stimuli (UV light or dimethylsulfoxide-soluble smoke particles (DSP)) or to medium conditioned by smooth muscle cells (SMC), basically or after injury to the SMC. An activity stimulating the release of prostacyclin was found together with growth inhibiting activity from arterial SMC, but dissociated from growth stimulating activity. The prostacyclin stimulating activity was increased when SMC were exposed to UV light, while DSP caused a decrease. EC directly exposed to UV light or DSP generally released more prostacyclin than controls. One exception was very low concentrations of DSP. UV light induced a burst of release in contrast to DSP where a continuous release after a two hours lag period was seen. It is concluded that EC will increase the release of prostacyclin in response to injury but the release pattern will depend on the kind and doses of the stimulus. SMC release prostacyclin stimulating activity for EC, which can be modified by exposure to toxic stimuli. The results might have applications for atherogenesis.

Polycyclic aromatic hydrocarbons of cigarette smoke have been suggested to be involved in atherogenesis. After being converted to epoxides by monooxidases in the arterial wall the hydrocarbons may exert toxic or mutagenic effects on the smooth muscle cells (SMC). In a previous study we found that dimethylbenzanthracene (DMBA), an inducer of arylhydrocarbonhydroxylase (AHH), increased SMC proliferation and viability. In the present work we intended to study whether these effects were mediated by AHH. Alpha-naphtoflavone (ANF), a non specific AHH inhibitor, decreased SMC proliferation. The effects of ANF were totally counteracted by serum, partially by albumin and not at all by platelet derived growth factor. AHH activity was not detectable nor basally nor after induction in SMC, and this made us conclude that the effects of DMBA and ANF on SMC proliferation were not mediated by AHH. On the other hand the activity of ornithine decarboxylase was influenced by DMBA and ANF in parallel to proliferation, suggesting the involvement of this enzyme in the described DMBA effects on SMC proliferation. This mechanism might be of relevance for the pathogenesis of atherosclerosis especially in relation to cigarette smoking.

The balance of growth stimulating and growth inhibiting factors in the arterial wall might be of importance in the pathogenesis of atherosclerosis. A method using different dialysis steps was used to allow the simultaneous study of micromolecular (dialysable) and macromolecular (non-dialysable) substances in conditioned media from bovine and human arterial endothelial cells and smooth muscle cells in culture. Micromolecular substances inhibited the proliferation of aortic smooth muscle cells and endothelial cells, while the macromolecular substances were growth stimulating. The effect of the micromolecular and macromolecular factors was dose dependent, but only the micromoleculars were affected by conditioning time. The micromoleculars were heat stable. The effect of macromoleculars was completely abolished by heating to 100 degrees C for 5 minutes. Confluent cells released relatively more growth inhibiting and less growth stimulating activity while the balance was changed in subconfluent cells showing an increased release of growth stimulating activity per cell. A co-culture model for endothelial and smooth muscle cells demonstrated that the confluent aortic endothelial cells released relatively more growth inhibiting activity. These models seem suitable for the study of interactions of growth inhibition and stimulation between arterial cells in vitro in the normal or pathological state.

Context Glucose-insulin-potassium (GIK) infusion is a widely applicable, low-cost therapy that has been postulated to improve mortality in patients with acute ST-segment elevation myocardial infarction (STEMI). Given the potential global importance of GIK infusion, a large, adequately powered randomized trial is required to determine the effect of GIK on mortality in patients with STEMI. Objective To determine the effect of high-dose GIK infusion on mortality in patients with STEMI. Design, setting, and participants Randomized controlled trial conducted in 470 centers worldwide among 20,201 patients with STEMI who presented within 12 hours of symptom onset. The mean age of patients was 58.6 years, and evidence-based therapies were commonly used. Intervention Patients were randomly assigned to receive GIK intravenous infusion for 24 hours plus usual care (n = 10,091) or to receive usual care alone (controls; n = 10,110). Main outcome measures Mortality, cardiac arrest, cardiogenic shock, and reinfarction at 30 days after randomization. Results At 30 days, 976 control patients (9.7%) and 1004 GIK infusion patients (10.0%) died (hazard ratio [HR], 1.03; 95% confidence interval [CI], 0.95-1.13; P = .45). There were no significant differences in the rates of cardiac arrest (1.5% [151/10 107] in control and 1.4% [139/10,088] in GIK infusion; HR, 0.93; 95% CI, 0.74-1.17; P = .51), cardiogenic shock (6.3% [640/10 107] vs 6.6% [667/10 088]; HR, 1.05; 95% CI, 0.94-1.17; P = .38), or reinfarction (2.4% [246/10,107] vs 2.3% [236/10,088]; HR, 0.98; 95% CI, 0.82-1.17; P = .81). The rates of heart failure at 7 days after randomization were also similar between the groups (16.9% [1711/10,107] vs 17.1% [1721/10,088]; HR, 1.01; 95% CI, 0.95-1.08; P = .72). The lack of benefit of GIK infusion on mortality was consistent in prespecified subgroups, including in those with and without diabetes, in those presenting with and without heart failure, in those presenting early and later after symptom onset, and in those receiving and not receiving reperfusion therapy (thrombolysis or primary percutaneous coronary intervention). Conclusion In this large, international randomized trial, high-dose GIK infusion had a neutral effect on mortality, cardiac arrest, and cardiogenic shock in patients with acute STEMI.