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Constructing high-quality white organic light-emitting diodes (WOLEDs) remains a big challenge because of high demands on the electroluminescence (EL) performance including high efficiency, excellent spectral stability, and low roll-off simultaneously. To achieve effective energy transfer and trap-assisted recombination in the emissive layer, herein, four Ir(III) phosphors, namely

Triptolide (TP) from Tripterygium wilfordii has been demonstrated to possess anti-inflammatory, immunosuppressive, and anticancer activities. TP is specially used for the treatment of awkward rheumatoid arthritis, but its clinical application is confined by intense side effects. It is reported that licorice can obviously reduce the toxicity of TP, but the detailed mechanisms involved have not been comprehensively investigated. The current study aimed to explore metabolomics characteristics of the toxic reaction induced by TP and the intervention effect of licorice water extraction (LWE) against such toxicity. Obtained urine samples from control, TP and TP + LWE treated rats were analyzed by UPLC/ESI-QTOF-MS. The metabolic profiles of the control and the TP group were well differentiated by the principal component analysis and orthogonal partial least squares-discriminant analysis. The toxicity of TP was demonstrated to be evolving along with the exposure time of TP. Eight potential biomarkers related to TP toxicity were successfully identified in urine samples. Furthermore, LWE treatment could attenuate the change in six of the eight identified biomarkers. Functional pathway analysis revealed that the alterations in these metabolites were associated with tryptophan, pantothenic acid, and porphyrin metabolism. Therefore, it was concluded that LWE demonstrated interventional effects on TP toxicity through regulation of tryptophan, pantothenic acid, and porphyrin metabolism pathways, which provided novel insights into the possible mechanisms of TP toxicity as well as the potential therapeutic effects of LWE against such toxicity.

A newly prepared tetraphenylethylene-based (TPE-based) covalent organic polymer (COP) named COP-1 exhibits high selectivity for sensing Fe3+ and the limit of detection (LOD) for Fe3+ is 0.42 μM, which is lower than the reported metal-free porous polymers. Furthermore, a WLED is fabricated and the CIE coordinates are (0.32, 0.33), very close to pure white light. The COP-1 shows potential applications in biosensors of Fe3+ and preparation of WLEDs.

Ginsenoside F2(F2), a protopanaxdiol type of saponin, was reported to inhibit human gastric cancer cells SGC7901. To better understand the molecular mechanisms of F2, an iTRAQ-based proteomics approach was applied to define protein expression profiles in SGC7901 cells in response to lower dose (20 μM) and shorter duration (12 hour) of F2treatment, compared with previous study. 205 proteins were screened in terms of the change in their expression level which met our predefined criteria. Further bioinformatics and experiments demonstrated that F2treatment downregulated PRR5 and RPS15 and upregulated RPL26, which are implicated in ribosomal protein-p53 signaling pathway. F2also inhibited CISD2, Bcl-xl, and NLRX1, which are associated with autophagic pathway. Furthermore, it was demonstrated that F2treatment increased Atg5, Atg7, Atg10, and PUMA, the critical downstream effectors of ribosomal protein-p53 signaling pathway, and Beclin-1, UVRAG, and AMBRA-1, the important molecules in Bcl-xl/Beclin-1 pathway. The 6 differentially abundant proteins, PRR5, CISD2, Bcl-xl, NLRX1, RPS15, and RPL26, were confirmed by western blot. Taken together, ribosomal protein-p53 signaling pathway and Bcl-xl/Beclin-1 pathway might be the most significantly regulated biological process by F2treatment in SGC7901 cells, which provided valuable insights into the deep understanding of the molecular mechanisms of F2for gastric cancer treatment.

The effects of environmental factors on the electrochemical behaviors of the materials 52M and 316L taken from a dissimilar metal weld exposed to high temperature primary water of pressurized water reactor (PWR) nuclear power plants were studied experimentally, mainly on the effects of impurities chloride and sulfate in water, temperature and dissolved oxygen on the polarization curves, in order to provide fundamental data for relevant research and development. The results showed that doping chloride and sulfate into the water caused the rise of the tendency to pitting and general corrosion tendencies of both materials. With the rise of temperature from 160 °C to 290 °C, the tendencies to corrosion in anodic condition increased. The rise of the dissolved oxygen led to the rises of both the corrosion potentials and also the tendencies to corrosion.

In this paper, the chemical composition of vehicle damage brake drum occurred in the heavy traffic accident on the highway is analyzed, and analyzed the influence on the braking performance of vehicles, pointed out that the direct cause of the accident is due to the friction surface of the drum brake has a penetrating crack.

The mechanical behaviors of dissimilar metal weld SA508-52M-316L in several environments were investigated by using tensile tests with smooth specimens, focusing on the behavior of SA508-52M weld part during slow strain rates testing (SSRT) at 290°C in nitrogen gas and in simulated primary water at different electrode potentials. The mechanical properties at room temperature of main materials were obtained first. When tested at 290°C, the weld exhibited characteristics of dynamic strain ageing (DSA), which was more significant when strain rate was decreased from 1x10-6(1/s) to 3.1 x10-7(1/s). When tested in the water at the potentials from-720 to +200mV(SHE) , SA508-52M specimens showed the mechanical behaviors almost the same as that in nitrogen gas, with ductile failure happened in the 52M bulk weld metal. When the potential was raised to +300 and +400mV(SHE), brittle failure of stress corrosion cracking (SCC) took place around the interface, causing the significant drop of elongation and reduction in area.

In analyzing the factors of traffic accident, the most important reasons are the influence of people, vehicles, roads, and the environment for traffic accident. Learning how to handle traffic accident normatively and identify the traffic accident correctly, is the important lesson need to be solved urgently. however, the current safety performance technical expertise work for accidental vehicles lack of according with relevant laws and regulations, scientific, adaptable, and workable identification norms. To solve this problem stated previously, this paper studies the technical identification standard of accident vehicles, which mainly introduces the effect, basis, selection of identification items of accidental vehicles safety performance technical identification, the content and demand of the identification process.

When oil field entered into the high water content period, liquid production capacity of oil wells had large fluctuation and poor regularity, which leaded to the error of human reading and bottom water density in the measurement process, the difficulty of measuring oil wells is gradually increasing. Therefore, the measurement of low producing well has aroused extensive attention. How to research and establish a suitable measuring device for low producing well, improve measurement accuracy and management level of intermittent oil wells has become a serious problem in oil production. Using automatic oil measuring system can improve the accuracy of measurement, which achieved the automatic measurement for the fluid and gas production and moisture content of oil wells.

The effects of soil type of Shanghai and electrode potential from cathodic protection point on near-neutral pH stress corrosion cracking (SCC) behavior of pipeline steel X60 has been investigated for structural integrity assessment. The SCC behavior was evaluated through slow strain rate tests (SSRT) at various electrode potentials in three solutions containing different typical soils. Results showed that the SCC susceptibility generally increased with decreasing electrode potential in all the three environments, with quick increase happening in the range from-1500 to-700mV(SCE). It is suggested that hydrogen induced cracking should dominate the SCC at low potentials. In cathodic potential range, the rank of the SCC susceptibility for soil type was Near-city soil > Cyan-purple soil > Cyan-yellow soil. In anodic potential range, SCC susceptibility curves mixed each other in the three solutions.

In the modern automotive industry, diaphragm spring clutch is widely used in light-duty and mini cars. Its service life depends on the performance and quality of pressure element-diaphragm spring. Improving diaphragm spring fatigue life and reducing elastic force decay rate will extend service life of diaphragm spring clutch. By comparing the fatigue life through bench test, shot peening on diaphragm spring can observably improve working fatigue life.

In recent years, the population size of Taiwan yellow cattle has drastically declined, even become endangered. A preservation project, Taiwan Yellow Cattle Genetic Preservation Project (TYCGPP), was carried out at the Livestock Research Institute (LRI) Hengchun branch (1988-present). An analysis of intra- and inter- population variability was performed to be the first step to preserve this precious genetic resource. In this work, a total number of 140 individuals selected from the five Taiwan yellow cattle populations were analyzed using 12 microsatellite markers (loci). These markers determined the level of genetic variation within and among populations as well as the phylogenetic structure. The total number of alleles detected (122, 10.28 per locus) and the expected heterozygosity (0.712) indicated that these five populations had a high level of genetic variability. Bayesian cluster analysis showed that the most likely number of groups was 2 (K = 2). Genetic differentiation among clusters was moderate (F ST = 0.095). The result of AMOVA showed that yellow cattle in Taiwan had maintained a high level of within-population genetic differentiation (91%), the remainder being accounted for by differentiation among subpopulations (4%), and by differentiation among regions (5%). The results of STRUCTURE and principal component analysis (PCA) revealed two divergent clusters. The individual unrooted phylogenetic tree showed that some Kinmen yellow cattle in the Hengchun facility (KMHC individuals) were overlapped with Taiwan yellow cattle (TW) and Taiwan yellow cattle Hengchun (HC) populations. Also, they were overlapped with Kinmen × Taiwan (KT) and Kinmen yellow cattle (KM) populations. It is possible that KMHC kept similar phenotypic characteristics and analogous genotypes between TW and KM. A significant inbreeding coefficient (F IS = 0.185; P < 0.01) was detected, suggesting a medium level of inbreeding for yellow cattle in Taiwan. The hypothesis that yellow cattle in Taiwan were derived from two different clusters was also supported by the phylogenetic tree constructed by the UPGMA, indicating that the yellow cattle in Taiwan and in Kinmen should be treated as two different management units. This result will be applied to maintain a good level of genetic variability and rusticity (stress-resistance) and to avoid further inbreeding for yellow cattle population in Taiwan.

With the rapid development of the automobile industry and transport, the increasing traffic accidents have become the serious problems for the traffic management. The important issue that we how to deal with the traffic accidents scientifically and make an accurate identification about the traffic accidents is badly in need of solving. Based on the current situation and research methods of traffic accidents at home and abroad, this paper illustrates the research on accident vehicle safety performance technology identification from one of factors causing traffic accidents-vehicles, which makes the identification for the accident vehicles about the operation process. The selection and process of identification items and information record will be strictly controlled to make the work quality and efficiency improve greatly.

To acquire the digital model of axial compressors on the actual projects, a Reverse Engineering procedure of the blade was developed based on point cloud data acquired with the handy laser scanner. For meeting the requirements of geometric characteristics and aerodynamic optimization design and improving acquiring efficiency of point cloud data, the laser triangulation was employed and auxiliary plane and mark points were put on the inlet, outlet and tip of the blade. For solving the problem of low accuracy of fitting surface on the blade, an interactive dividing method of surface slices which based on the streamline, meridian line, contour and its extension line, was presented, it showed that reconstructed surface model can meet the actual projects needs. A completed set of RE technology for axial compressor blades has been developed, and it has been used in actual project combing with the maintenance of a large axial compressor blade.

Ginsenoside F2 (F2), a protopanaxdiol type of saponin, was reported to inhibit human gastric cancer cells SGC7901. To better understand the molecular mechanisms of F2, an iTRAQ-based proteomics approach was applied to define protein expression profiles in SGC7901 cells in response to lower dose (20 μM) and shorter duration (12 hour) of F2 treatment, compared with previous study. 205 proteins were screened in terms of the change in their expression level which met our predefined criteria. Further bioinformatics and experiments demonstrated that F2 treatment downregulated PRR5 and RPS15 and upregulated RPL26, which are implicated in ribosomal protein-p53 signaling pathway. F2 also inhibited CISD2, Bcl-xl, and NLRX1, which are associated with autophagic pathway. Furthermore, it was demonstrated that F2 treatment increased Atg5, Atg7, Atg10, and PUMA, the critical downstream effectors of ribosomal protein-p53 signaling pathway, and Beclin-1, UVRAG, and AMBRA-1, the important molecules in Bcl-xl/Beclin-1 pathway. The 6 differentially abundant proteins, PRR5, CISD2, Bcl-xl, NLRX1, RPS15, and RPL26, were confirmed by western blot. Taken together, ribosomal protein-p53 signaling pathway and Bcl-xl/Beclin-1 pathway might be the most significantly regulated biological process by F2 treatment in SGC7901 cells, which provided valuable insights into the deep understanding of the molecular mechanisms of F2 for gastric cancer treatment.

The microstructures and mechanical properties of a dissimilar metal weld A508/52M/316L used in the primary water system of pressurized water reactor (PWR) nuclear power plants were investigated. The weld exhibits complicated microstructures, with significant change around the interfaces A508/52M and 52M/316L. The variations of main elements in 52M weld metal are greater than those in the A508 and 316L, with significant changes in the zones closed to the interfaces. The bulk 52M weld metal has higher and more uneven hardness than both of the base metals A508 and 316L. The HAZ of A508 exhibits the highest hardness value in the weld. The area around the A508/52M interface is the most weak part for stress corrosion cracking (SCC) resistance of the weld in simulated PWR primary water at 290°C. SCC was only found in the specimens tested at +200mV(SHE) but not in those tested at both -780mV and Ecorr (about -500mV).

Stress corrosion cracking (SCC) behaviors of pipeline steel X70 in various near-neutral pH soil environments with characteristics of eastern China have been studied through electrochemical measurements and slow strain rate tests (SSRT) at various electrode potentials in four solutions containing different typical soils in eastern China as well as in NS-4 solution. The SCC susceptibility in the four soil solutions was generally higher than that in NS-4 solution. There was a general trend that SCC susceptibility increased with decreasing the potential, suggesting that hydrogen induced cracking probably plays a key role in the cracking at least at low potentials and the parameters of cathodic protection in engineering should be carefully optimized to avoid SCC.

A surface roughness intelligent prediction control system during grinding is built. The system is composed of fuzzy neural network prediction subsystem and fuzzy neural network controller. In the fuzzy neural network prediction subsystem, the vibration data are added to the inputs besides the grinding condition, such as feed and speed, so as to improve the dynamic performance of the prediction subsystem. The fuzzy neural network controller is able to adapt grinding parameters in process to improve the surface roughness of machined parts when the roughness is not meeting requirements. Experiment verifies that the developed prediction control system is feasible and has high prediction and control accuracy.

To better understand the interaction between Schistosoma japonicum and its murine host, we characterized the immune response of CD4+ T cells generated during an experimental S. japonicum infection based on different key aspects, from gene expression to cell behavior. Mouse oligonucleotide microarrays were used to compare gene expression profiles of CD4+ T cells from spleens of mice at 0, 3, 6 and 13 weeks post-infection. Flow cytometry analysis was used to determine type 1 and type 2 cytokine-secreting CD4+ T cells, to test apoptosis of CD4+ T cells and to count CD4+CD25+ T cells, a kind of regulatory subpopulation of CD4+ T cells. The percentage of interleukin-4-producing CD4+ T cells was found to be much higher than that of γ-interferon-producing cells, especially after stimulation with S. japonicum egg antigen, which was consistent with type 1 and type 2 cytokine gene expression in the genechip. Microarray data also showed that S. japonicum induced the increased expression of Th2 response-related genes, whereas some transcripts related to the Th1 responsive pathway were depressed. Flow cytometry analysis showed a marked increase in the apoptotic CD4+ T cells from 6 weeks post-infection and in the ratio of CD4+CD25+ to CD4+ T cells in infected mice after 13 weeks. We therefore concluded that experimental infection of mice with S. japonicum resulted in a Th2-skewed immune response, which was to a great extent monitored by the immune regulatory network, including cytokine cross-modulation, cell apoptosis and the subpopulation of regulatory cells. Edited by Ming-Hua XU

A size intelligent prediction control model during traverse grinding is constructed. The model is composed of the neural network prediction model, the deformation optimal adaptive control system and fuzzy control model. Dynamic Elman network is used in the prediction model. The first and the second derivative of the actual amount removed from the workpiece are added into the network input, which can greatly improve the prediction accuracy. The flexible factor is introduced to the fuzzy control model, which can self-adapt and adjust the quantification factor and scale factor in the fuzzy control. Simulation and experiment verify that the developed prediction control model is feasible and has high prediction and control precision.

During the process of plunge grinding, a test piece can be axially grooved with thermocouple embedded, thermo-electromotive force will be conducted through collecting ring and then after A/D converting, data will be digitally acquired and online test will be realized. Based on the thermal theories, this paper presents a simple model to calculate the workpiece’s contact zone temperature during plunge grinding process. This model can be used to predict and calculate the grinding temperature easily. An empirical formula calculating the temperature of the grinding contact surface had been obtained through multivariate linear regression analysis experiments. The thermometric system showed in this paper had solved the knotty problem that the grinding temperature was very difficult to measure for plunge grinding. Compared with traditional method, the testing method adopted by the author will give more accurate result and more closely represent the test piece situation. The results of the computer simulation and the experiments proved the exactitude of the thermal model and the feasibility of the thermometric system.

Effects of some environmental factors on stress corrosion cracking (SCC) of pipeline steel X-70 both in near-neutral pH environments, including NS4 solution and several solutions containing main types of soil in the eastern part of China, and in high pH solution were studied by means of electrochemical measurement and slow strain rate testing (SSRT). The anodic polarization curves showed different features in near-neutral pH and high pH solutions in terms of active-passive transition behavior. In near-neutral pH solutions, the cracking mode was transgranular with the feature of quasi-cleavage, the susceptibility to SCC increased with decreasing potential, pH and temperature as well as increasing CO2, indicating a dominant mechanism of hydrogen induced cracking (HIC). In high pH solutions, the cracking behavior was similar to that in near-neutral pH solutions when the specimens were polarized at cathodic potentials, but quite different at anodic potentials. A comparison of the electrochemical behavior with the SCC potential region indicated a dominant SCC mechanism associated with anodic dissolution (AD) of X70 in high pH solution at anodic potentials. A preliminary experimental potential (E)-pH-SCC diagram has been established for X70 in near-neutral pH environments.

The effects of cold working and heat treatment on caustic stress corrosion cracking (SCC) of mill annealed (MA) alloy 800M in boiling solution of 50%NaOH+0.3%SiO2+0.3%Na2S2O3 were investigated by means of microstructure examination, tensile test, X-ray stress analysis, SCC testing of C-rings, Auger electron spectroscopy (AES), scanning electron microscopy (SEM) and metallography. The microstructure of alloy 800M under tested conditions was austenite. With a train of 25% by cold working, the grains of alloy 800M became longer, yield strength (YS) and ultimate tensile strength (UTS) increased, elongation (δ ) decreased, residual stress and the susceptibility to SCC increased. With increasing temperature of heat treatment of alloy 800M with cold working, the grains became bigger , residual stress, YS and UTS decreased and δ increased, the susceptibility to SCC of alloy 800M decreased. In boiling caustic solution, SCC cracks on the surfaces of C-ring specimens polarized potentiostatically at –20mV/SCE initiated from pitting and propagated along grain boundaries. AES analysis indicated that the surface films on MA alloy 800M were enriched in nickel and depleted in iron and chromium.

Crack propagation of X-70 pipeline steel in near-neutral pH solution was studied under different modes of cyclic loading. A revised equation of crack growth rate vs. Δ K was obtained. Average crack growth rate increased with cycles under conditions of different R values. Linear shape notch specimen made cracks much easier to initiate and propagate than V-shaped notch specimen did. For different R values, the curves of crack growth rate with cycles were similar, but the platform propagation period and quick propagation period were different obviously. Crack growth rate at both periods increased and thus failure time decreased markedly with decrease of R value. The propagation directions of cracks were different under different cyclic loading conditions. Under mode I (single tensile stress) cyclic loading, cracks were straight and perpendicular to the tensile stress axis, while under mixed-mode I/III (tensile/shear stress) cyclic loading, cracks were sinuous and did not propagate in the direction perpendicular to the main tensile stress axis.

Th1-type cytokines produced by the stimulation of Th1-type epitopes derived from defined schistosome-associated antigens are correlated with the development of resistance to the parasite infection. Schistosoma mansoni 28 kDa glutathione-S-transferase (Sm28GST), a major detoxification enzyme, has been recognized as a vaccine candidate and a phase II clinical trial has been carried out. Sheep immunized with recombinant Schistosoma japonicum 28GST (Sj28GST) have shown immune protection against the parasite infection. In the present study, six candidate peptides (P1, P2, P3, P4, P7 and P8) from Sj28GST were predicted, using software, to be T cell epitopes, and peptides P5 and P6 were designed by extending five amino acids at the N-terminal and C-terminal of P1, respectively. The peptide 190-211 aa in Sj28GST corresponding to the Th1-type epitope (190-211 aa) identified from Sm28GST was selected and named P9. The nine candidate peptides were synthesized or produced as the fusion protein with thioredoxin in the pET32c(+)/BL21(DE3) system. Their capacity to induce a Th1-type response in vitro was measured using lymphocyte proliferation, cytokine detection experiments and flow cytometry. The results showed that P6 (73-86 aa) generated the strongest stimulation effect on T cells among the nine candidate peptides, and drove the highest level of IFN-gamma and IL-2. Therefore, P6 is a functional Th1-type T cell epitope that is different from that in Sm28GST, and will be useful for the development of effective vaccines which can trigger acquired immunity against S. japonicum. Moreover, our strategy of identifying the Th1-type epitope by a combination of software prediction and experimental confirmation provides a convenient and cost-saving alternative approach to previous methods.

To understand the natural history of immune responses centering CD4 + T cells at genetic level during experimental infection with Schistosoma japonicum ( S. japonicum ), the mRNA profiles of CD4 + T cells from spleens of mice at 0, 3, 6, and 13 weeks after the onset of the infection, were compared using mouse oliogonucleotide microarrays (Affymetrix GeneChip U74A). Of about 12,000 mouse probe sets in a microarray, nearly 10% encoded a variety of immune regulators, including many cytokine and chemokine genes, immunoglobulin-related genes, and genes related to apoptosis and the stress response. These changed in transcript representation as the schistosome infection progressed, and a key finding, which was validated by semi-quantitative PCR, was that a significant portion of the genes which were down-regulated as infection progressed coded for interferon (IFN)-inducible molecules, including GTPases, transcription factors and chemokines. The results thus showed that there is a characteristic change in IFN-inducible gene expression over the course of the schistosome infection, and it is suggested that the IFN-γ-regulated GTPase family may be involved in IFN-mediated resistance against S. japonicum .

To better understand the interaction between Schistosoma japonicum and its murine host, we characterized the immune response of CD4+ T cells generated during an experimental S. japonicum infection based on different key aspects, from gene expression to cell behavior. Mouse oligonucleotide microarrays were used to compare gene expression profiles of CD4+ T cells from spleens of mice at 0, 3, 6 and 13 weeks post-infection. Flow cytometry analysis was used to determine type 1 and type 2 cytokine-secreting CD4+ T cells, to test apoptosis of CD4+ T cells and to count CD4+CD25+ T cells, a kind of regulatory subpopulation of CD4+ T cells. The percentage of interleukin-4-producing CD4+ T cells was found to be much higher than that of gamma-interferon-producing cells, especially after stimulation with S. japonicum egg antigen, which was consistent with type 1 and type 2 cytokine gene expression in the genechip. Microarray data also showed that S. japonicum induced the increased expression of Th2 response-related genes, whereas some transcripts related to the Th1 responsive pathway were depressed. Flow cytometry analysis showed a marked increase in the apoptotic CD4+ T cells from 6 weeks post-infection and in the ratio of CD4+CD25+ to CD4+ T cells in infected mice after 13 weeks. We therefore concluded that experimental infection of mice with S. japonicum resulted in a Th2-skewed immune response, which was to a great extent monitored by the immune regulatory network, including cytokine cross-modulation, cell apoptosis and the subpopulation of regulatory cells.

To investigate the molecular characteristic of interferon-gamma mediating protective immunity against schistosomiasis japonica in mice.CD4+ T cells were isolated from spleens of mice infected with Schistosoma japonicum at different time-points. The cDNA microarray technique combined with RT-PCR was used to explore IFN-gamma inducible GTPase family gene expression profile of CD4+ T cell. IGTP, a representative IFN-gamma, inducible GTPase having vital anti-infection activity, was amplified from spleen of BALB/c mice using RT-PCR, then cloned into pGEM(r)-T easy vector for sequencing.IFN-gamma inducible GTPase family had the similar characteristic over the course of S. japonicum infection. The gene expression of these members were up-regulated or had little change at 3 wk post-infection, then down-modulated from 6 wk to 13 wk post-infection, which was also confirmed by RT-PCR. As for IGTP, two inserts were identified after sequencing. One was 142 bp shorter than another, but the fragment was lost due to low annealing temperature.There is a dramatic inhibition of IFN-gamma pathway and IFN-gamma-dependent anti-infective immunity during the infection of S. japonicum.

To predict T-cell epitopes of recombinant schistosoma japonicum 28 kDa glutathione-S-transferase(GST) with software and identify the Th1 type T-cell epitopes by experiments.T-cell epitopes of recombinant schistosoma japonicum 28kDa GST were predicted with software and several epitopic candidates were screened from them according to their scores. Some of the epitopic candidates were synthesized and the other epitope peptides fused with thioredoxin(Trx) were expressed in E.coli BL21(DE3) and purified by Ni(+) column affinity chromatography. C57BL/6 (H-2(b)) mice's were immunized via peritoneal infection with ultraviolet ray irradiated-cercariae and then boosted with recombinant schistosoma japonicum 28 kDa GST. The immunized mice splenocytes were prepared, cultured and stimulated with synthesized epitope peptides and epitope peptide fusion proteins, respectively. Stimulation activity of synthesized epitope peptides and epitope peptides fusion proteins were assayed by lymphocyte proliferation assay. Levels of IFN-gamma and IL-2 were measured by ELISA. CD4(+) T cells and T cells secreting IFN-gamma and IL-4 were detected by flow cytometry.Epitope P6(73-86aa) among 9 epitopic candidates could generate the strongest stimulation effect on splenocytes, stimulate secretion of higher levels of IFN-gamma and IL-2, and induce more IFN-gamma(+) and IL-4 (+) T cells.The recombinant 28 kDa GST possesses functional Th1 type T-cell epitope.

To identify the T cell epitopes on 22.6 kDa antigen of Schistosoma japonicum (Sj22.6).The primary structure of Sj22.6 molecule was analysed using various predictive algorithms and a panel of 4 peptides were acquired. Their oligonucleotides were designed, synthesized and inserted into the multiple cloning site of plasmid pET-32c(+). The recombinant plasmids were transformed into E. coli BL21 and identified by endonuclease digestion and sequencing. The positive clones containing the recombinant plasmids could express specific fusion proteins (trx-epitope, MW approximately 20 kDa) induced by IPTG. The fusion protein with 6 x His could be coupled with NTA resin specifically, and purified by elusion of the column with buffer containing imidazole. The purified fusion proteins were incubated with splenocytes of C3H mice and then, the proliferation of splenocytes was determined by 3H-TdR incorporation assay.The recombinant plasmids were constructed successfully and the positive clones containing the recombinant plasmids expressed specific fusion proteins. Three of the purified fusion proteins (P4, P5, P6) could stimulate the lymphocyte proliferation.Three T cell epitopes on Sj22.6 antigen were identified.

To observe the effect of intermittent parathyroid hormone (PTH) administration on bone histomorphology of relatively old ovariectomized rats.The 6-month-old female SD rats were randomly divided into 5 groups: (1) sham-operated for baseline (ShamB, n=5), (2)ovariectomized for baseline (OVXB, n=6), (3) Sham-operated for end point (ShamE, n=6), (4) ovariectomized for end point (OVXE, n=6), (5) ovariectomized for PTH treatment (OVXEP, n=6). ShamB and OVXB rats were sacrificed 3 months after operation, ShamE, OVXE and OVXEP rats were sacrificed 4.5 months after operation. During 3-4.5 months after operation, OVXEP rats received daily subcutaneous injection of rhPTH1-84, while ShamE and OVXE received vehicle injection. The proximal tibiae of all rats were processed without decalcification for quantitative bone histomorphometry.The percent trabecular area (TbAr) of OVXEP was significantly greater than that of OVXE (P0.05), and was similar to that of OVXB (P0.05), but was smaller than that of ShamE (P0.05); the trabecular thickness (TbTh) of OVXEP was thicker than any other group (all, P0.05); the trabecular number (TbN) of OVXEP was only slightly higher than that of OVXE; the percent labeled perimeter (LPm), mineral apposition rate (MAR) and bone formation rate with bone area as referent (BFR/BV) of OVXEP were all higher than those of ShamE and OVXE respectively (P0.01), whereas the osteoclast number (N of Oc) of OVXEP was similar to those of ShamE and OVXE (P0.05).Short-term intermittent injection of rhPTH1-84 can prevent further bone loss in 9-month-old rats 3 months after ovariectomy, the mechanisms of this therapy are that PTH could increase TbTh while not alter TbN, and promote bone-forming activity while not influence bone-resorptive activity.