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Our study revealed for the first time that the zidovudine-amikacin combination shows a significant bactericidal effect against amikacin-resistant MDR, XDR, and PDR Enterobacteriales . Second, using in vitro and in vivo approaches, our study showed that zidovudine strongly synergized with amikacin against amikacin-resistant MDR Enterobacteriales isolates.

Based on 15N tracer technique, absorption of different concentrations of ammonium nitrogen (N-NH4+), nitrate nitrogen (N-NO3-) and glycine (N-Gly) by root of six species of alpine forage (Puccinellia tenuiflora, Poa crymophila, Festuca sinensis, Elymus nutans, Elymus sibiricus and Bromus inermis) was studied in a hydroponic culture. The uptake kinetic parameter was analyzed according to Michaelis-Menten equation. The Michaelis-Menten equation represents the velocity equation for the relationship between the initial rate of an enzymatic reaction and the substrate concentration. The result showed that the absorption range of ammonium nitrogen, nitrate nitrogen and glycine by root of six species of alpine plant were 1.1–20.9 μmol·g–1·h–1, 0.4–3.4 μmol·g–1·h–1 and 0.1–3.7 μmol·g–1·h–1, which accounts for 68.8%-74.7%, 12.0%-27.0% and 4.3%-13.4% of total absorptivity, respectively. The six kinds of P. tenuiflora, P. crymophila, F. sinensis, E. nutans, E. sibiricus and B. inermis showed significant difference in nitrogen absorption. At the same concentration, the absorption of nitrogen in different forms of the same herbage is different. The absorptive amount of ammonium nitrogen was the highest among them, then the glycine, the nitrate nitrogen was least absorbed. The results could provide a theoretical basis for nitrogen utilization in alpine forages. For example, P. tenuiflora showed a much higher ability of absorbing nitrogen nutrition in a high salt environment and could be a more suitable herbage to be planted in saline-alkali soil in the Qinghai-Tibet Plateau as compared with E. nutans.

Tunicosaponins are natural products extracted from Psammosilene tunicoides, which is an important ingredient of Yunnan Baiyao Powder, an ancient and famous Asian herbal medicine. The representative aglycones of tunicosaponins are the oleanane-type triterpenoids of gypsogenin and quillaic acid, which were found to manipulate a broad range of virus-host fusion via wrapping the heptad repeat-2 (HR2) domain prevalent in viral envelopes. However, the unknown biosynthetic pathway and difficulty in chemical synthesis hinder the therapeutic use of tunicosaponins. Here, two novel cytochrome P450-dependent monooxygenases that take part in the biosynthesis of tunicosaponins, CYP716A262 (CYP091) and CYP72A567 (CYP099), were identified from P. tunicoides. In addition, the whole biosynthesis pathway of the tunicosaponin aglycones was reconstituted in yeast by transforming the platform strain BY-bAS with the CYP716A262 and CYP716A567 genes, the resulting strain could produce 146.84 and 314.01 mg/L of gypsogenin and quillaic acid, respectively. This synthetic biology platform for complicated metabolic pathways elucidation and microbial cell factories construction can provide alternative sources of important natural products, helping conserve natural plant resources.

Numerous studies have shown that zinc oxide nanoparticles (nZnO) have an inhibitory effect on wastewater biotreatment, where doses exceeding ambient concentrations are used. However, the effect of ambient concentrations of ZnO (1 mg/L) on anaerobic digestion processes is not clear. Herein, this study comprehensively explored the impact of nZnO on the denitrification performance and core microbial community of activated sludge under ambient concentrations. Results showed that only 0.075 mg/L nZnO had shown a beneficial effect on nitrogen removal by activated sludge. When nZnO concentration reached 0.75 mg/L, significant enhancement of nitrate reduction and mitigation of nitrite accumulation were observed, indicating a remarkable stimulatory effect on nitrogen removal. Simultaneously, nZnO could weaken the sludge surface charge and improve the secretion of extracellular polymeric substances, thus enhancing sludge flocculation for denitrification. Microbial community analysis revealed that nZnO exposure increased the relative abundance of denitrifying bacteria, which could contribute to the reinforcement of traditional denitrification. Furthermore, exogenous addition of NH

The spread of antibiotic resistance genes (ARGs) in the environment has aroused growing concern for human health and ecological safety. Recent studies have confirmed that engineered nanomaterials can increase the environmental risk of ARG dissemination mediated by conjugation and transformation. However, whether nanomaterials can mediate the transductive transfer of ARGs by phage infection has not been reported. In this work, the effect of nano-TiO2 on the horizontal transfer of ARGs to E. coli TG1 through transduction by constructed phage gM13 was investigated. Our results showed that nano-TiO2 concentration, particle size, mating time and the ratio of gM13/TG1 could influence the transductive transfer of ARGs. Further studies revealed that nano-TiO2 could promote bacteriophage attachment on cell surfaces, which contributed to gM13 infection. Meanwhile, increasing membrane permeability induced by nano-TiO2 could alleviate transmembrane resistance, which facilitated the infectious entry of phage gM13 into periplasmic space. The expressions of pilus-related genes were improved when E. coli TG1 was exposed to nano-TiO2. Thus, this work is beneficial for gaining a better understanding about the multiple environmental effects of increasingly released nanomaterials and is useful for the control of ARG dissemination in the environment.

Photocatalytic catalysis is widely used for pollutant degradation. Since some pollutants with oxidative nature are readily reduced rather than oxidized and reductive reaction caused by photogenerated electrons is limited in the presence of oxygen, photocatalytic reduction process is more applicable for the degradation of pollutants with oxidative nature than oxidation. In this work, a novel bio-photoelectric reductive degradation system (BPRDS), composed of an electrochemically active bacterium Shewanella oneidensis MR-1 and a visible-light photocatalyst Ag3PO4, was established under anaerobic conditions and its photodegradation performance was evaluated through degrading rhodamine B (RhB), a typical organic pollutant. The as-synthesized Ag3PO4 nanoparticles exhibited absorption in the entire visible spectral range of 400–800 nm. RhB could be degraded in BPRDS with visible light irradiation under anaerobic conditions, but not be decomposed in the absence of Shewanella cells. Block of Mtr respiratory pathway, a transmembrane electron transport chain, resulted in a reduction in degradation rate of RHB in BPRDS. Dose of riboflavin also substantially decreased the RhB degradation. These results suggest that the electrons released by Shewanella were involved in the RhB photodegradation, which was achieved via a stepwise N-deethylation process. In BPRDS, RhB was degraded by photoreduction, rather than photooxidation. This work is useful to develop integrated physico-chemical-microbial systems for pollutant degradation, facilitate better understanding about the biophotoelectric reductive degradation mechanisms and beneficial to their applications for environmental remediation. Keywords: Shewanella oneidensis MR-1, Anaerobic degradation, Microbial electron transfer, Nanomaterial, Photoreduction

Although the ecological safety of nanomaterials is of widespread concern, their current ambient concentrations are not yet sufficient to cause serious toxic effects. Thus, the nontoxic bioimpact of nanomaterials in wastewater treatment has attracted increasing attention. In this study, the effect of nano zinc oxide (nZnO), one of the most widely used nanomaterials, on the anaerobic biodegradation of methyl orange (MO) by Shewanella oneidensis MR-1 was comprehensively investigated. High-dosage nZnO (0.5 mg/L) caused severe toxic stress on S. oneidensis MR-1, resulting in the decrease in decolorization efficiency. However, nZnO at ambient concentrations could act as nanostimulants and promote the anaerobic removal of MO by S. oneidensis MR-1, which should be attributed to the improvement of decolorization efficiency rather than cell proliferation. The dissolved Zn

Environmental pollution caused by antibiotic resistance genes (ARGs) has attracted wide concerns, and various approaches have been proposed to control ARGs dissemination. TiO

Recently, paradoxical combinations of colistin with anti-Gram-positive bacterial agents were introduced as a treatment alternative for multidrug-resistant Acinetobacter baumannii (MDRAB) infection. We assessed the therapeutic efficacy of the colistin–linezolid combination regimen in vitro and in a murine model of Acinetobacter baumannii pneumonia. A multidrug-resistant clinical strain (MDRAB31) and an extensively drug-resistant clinical strain (XDRAB78) were used in this study. The survival rates of mice and bacterial counts in lung tissue were used to assess the effects of colistin–linezolid combination. The survival rates of colistin–linezolid combination groups significantly increased compared with colistin groups for MDRAB31 (72% versus 32%, P = 0.03) and for XDRAB78 (92% versus 68%, P = 0.031). The colistin–linezolid combination groups significantly reduced the bacterial counts in lung tissue compared with colistin groups for MDRAB31 and for XDRAB78 (P

Coronary artery disease (CAD) is a leading cause of death, and microRNAs (miRNAs) are widely involved in physiological and pathological processes of CAD. We chose the targetscore method calculated via the variational Bayesian Gaussian mixture model (VB-GMM) as the prediction method of target genes. By observing the density overlap, we selected the thresholds of miRNA-1 and miRNA-155. In total, 18 target genes of miRNA-1, and 19 target genes of miRNA-155 were identified. The threshold of miRNA-146a was selected using the |logFC| value, and 16 target genes were screened out. In this study, our major contribution was to predict the target messenger RNAs (mRNAs) of the chosen miRNAs with the gene expression profiles, which can effectively reduce the workload of screening. Although the validated genes constituted only a small part in the final prediction results, it is a good sign for research in the future. It means that we could provide new research aims for future studies focusing on miRNA regulatory mechanisms.

C-2α hydroxylated triterpenoids are a large class of plant secondary metabolites. These compounds, such as maslinic, corosolic and alphitolic acid, have important biological activities against HIV, cancer and diabetes. However, the biosynthesis pathways of these compounds have not been completely elucidated. Specifically, the cytochrome P450 (CYP) enzyme responsible for C-2α hydroxylation was unknown. In this study, a novel CYP enzyme that catalyzes C-2α hydroxylation was identified in Crataegus pinnatifida (Hawthorn) using a metabolic engineering platform. It is a multifunctional enzyme with C-2α oxidase activity on oleanane-, ursane- and lupane-type pentacyclic triterpenoids. In addition, the complete biosynthesis pathways of these three triterpenoids were reconstituted in yeast, resulting in the production of 384, 141 and 23 mg/L of maslinic, corosolic and alphitolic acid, respectively. This metabolic engineering platform for functional gene identification and strain engineering can serve as the basis for creating alternative pathways for the microbial production of important natural products.

This paper represents a novel less conservative stability criterion for time-delay systems with nonlinear disturbances. The main purpose is to obtain larger upper bound of the time-varying delay. A suitable Lyapunov- Krasovskii functional (LKF) with triple integral terms is constructed. Then, two new generalized double integral (GDI) inequalities are proposed which encompass Wirtinger-based double inequality as a special case. A simple case of the proposed GDI inequality is utilized to estimate double integral terms in the time derivative of the constructed LKF. Further, an improved delay-dependent stability criterion is derived in the form of linear matrix inequalities (LMIs). Finally, some numerical examples are given to illustrate the improvement of the proposed criteria.

The poor survival of mesenchymal stem cells (MSCs) compromises the efficacy of stem cell therapy. Growth factor deprivation is one of the important factors that have challenged the survival of donor MSCs in cell therapy. In this study, the aim was to evaluate the effect of serum deprivation on the cell death of MSCs and to investigate the underlying mechanisms. Apoptosis of MSCs was evaluated with Hoechst 33342/PI staining. Signaling pathways involved in serum-deprivation induced apoptosis were analyzed using Western blotting. The results revealed that serum deprivation induced apoptosis in MSCs within 72 h of treatment. Serum deprivation was shown to lead to protein expression alterations in Bax, Bcl-2, casepase-3, casepase-8, GRP78, and CHOP during experiments. The data suggested that the mitochondria death pathway, the extrinsic apoptotic pathway and the endoplastic reticulum(ER) stress pathway were all involved in MSCs apoptosis. The increase in expression of CHOP and the simultaneous decrease in Bcl-2 expression suggest a synergistic effect in apoptosis induction in both the mitochondrion and the ER.

Organic molecular sensors have the advantage of being used through easy, fast, economical and reliable optical methods for detecting toxic metal ions in the environment. In the present work, a simple but specific organic ligand N , N -(3,3′-dimethyl biphenyl)-bis(4-diethylaminosalicyladimine) ( Q2 ) was designed and synthesized according to the excited state intramolecular proton transfer (ESIPT). Q2 can be regarded as a colorimetric and fluorescent sensor for relay recognition of Cu 2+ and H 2 PO 4 − in DMSO/H 2 O (8:2, v/v) HEPES buffer solutions. Moreover, sensor Q2 showed a highly sensitive and selective response towards Cu 2+ and H 2 PO 4 − over other metal ions and anions. Particularly, the fluorescence “ON–OFF–ON” responding circle could be repeated over 4 times by the sequential addition of Cu 2+ and H 2 PO 4 − . Notably, the actual usage of sensor Q2 was further demonstrated by test kits and silica gel plates. The fluorescence changes of Q2 upon the addition of Cu 2+ and H 2 PO 4 − were utilized as an INHIBIT logic gate at the molecular level, using Cu 2+ and H 2 PO 4 − as chemical inputs and the fluorescence intensity signal as the output.

Through the Cooperative Study of the Kuroshio and Adjacent Regions (CSK) program during 1965–1979, the capacities of current member states (MSs) of the Sub-Commission for the Western Pacific (WESTPAC) of the Intergovernmental Oceanographic Commission (IOC) were enhanced with regard to regional ocean science and data management. Following the termination of the CSK in 1979, each MS continued the work to advance ocean science. The results of scientific studies of the Kuroshio and its adjacent regions have been published by various experts including many from the MSs of the WESTPAC; however, to-date, there has been no systematic approach to the research of the Kuroshio and its adjacent regions. This review considered the Kuroshio from the regional perspective of experts of the MSs, that is, from the perspectives of MSs, science, and the future prospects. Experts from each MS reviewed past activities and contributions and reviewed the knowledge gaps in the fields of physical, biological, and biogeochemical science. Many scientific questions remain regarding the path of the Kuroshio from south to north, as well as associated phenomena, including mesoscale eddies and fronts, the important roles of ocean variations in adjacent regions, and the different roles and mechanisms of air–sea interactions in low- and mid-latitude areas. Despite considerable effort by many biologists, substantial gaps remain in our biological knowledge of the region. The Kuroshio and its adjacent regions comprise one of the areas of the world with high biodiversity; however, there has been insufficient research into what is the cause of this high biodiversity. From a biogeochemical aspect, high-resolution spatiotemporal observations will be required to understand interactions with physical processes both in the Kuroshio region and in the marginal seas. It has been highlighted that long-term fixed-location observations will be needed to understand the key mechanisms of biogeochemical processes, particularly in relation to climate change. Finally, the report summarized the future perspectives. Based on recognition of the current circumstances and with acknowledgment of the potential short-term future capabilities of MSs, the possible uses of new technologies and frameworks were discussed. Since the implementation of the United Nations Convention on the Law of the Sea, which came into force in 1994, it has been difficult to conduct observations in the exclusive economic zone (EEZ) of other regional states. Thus, new frameworks and/or technologies will be needed to ensure the success of future studies of the Kuroshio.

Environmental pollution caused by antibiotic resistance genes (ARGs) has attracted wide concerns, and various approaches have been proposed to control ARGs dissemination. TiO2 photoexcitation under UV irradiation has been used for such a purpose. But the actual UV intensity is insufficient to trigger the production of reactive oxygen species (ROS) in the aqueous environment. Thus, it is interesting to know how mild photoexcitation of TiO2 with low-intensity UV affects the horizontal transfer of ARGs. In this work, the impact of TiO2 photoexcitation on the transductant efficiency of constructed filamentous phage gM13 to its host Escherichia coli TG1 was investigated. Although individual treatment with nano-TiO2 and UV irradiation both improved the phage infection, TiO2 photoexcitation exhibited a clear synergistic promotion effect. However, excessive UV irradiation resulted in a decrease in transductant formation, implying severe oxidative damage to the phage and bacterial cells. Extracellular ROS produced by moderate photoexcitation of TiO2 could increase the outer membrane permeability, which facilitated phage infection. The increase in pili synthesis induced by intracellular ROS provided more sites for phage recognition and invasion in the presence of TiO2 photoexcitation, which contributed to the transduction process. Our work provides a novel insight into the impact of TiO2 photoexcitation on ARGs diffusion and is helpful for better understanding non-toxic environmental effect of nanomaterials.

Electrochemically active bacteria (EAB) are effective for the bioreduction of nitroaromatic compounds (NACs), but the exact reduction mechanisms are unclear yet. Therefore, 3-nitrobenzenesulfonate (NBS) was used to explore the biodegradation mechanism of NACs by EAB. Results show that NBS could be anaerobically degraded by Shewanella oneidensis MR-1. The generation of aminoaromatic compounds was accompanied with the NBS reduction, indicating that NBS was biodegraded via reductive approach by S. oneidensis MR-1. The impacts of NBS concentration and cell density on the NBS reduction were evaluated. The removal of NBS depends mainly on the transmembrane electron transfer of S. oneidensis MR-1. Impairment of Mtr respiratory pathway was found to mitigate the reduction of NBS, suggesting that the anaerobic biodegradation of NBS occurred extracellularly. Knocking out cymA severely impaired the extracellular reduction ability of S. oneidensis MR-1. However, the phenotype of ΔcymA mutant could be compensated by the exogenous electron mediators, implying the trans-outer membrane diffusion of mediators into the periplasmic space. This work provides a new insight into the anaerobic reduction of aromatic contaminants by EAB.

The overuse of antibiotics has resulted in contamination of antibiotics and genes encoding multidrug resistance in some water sources in China. Antibiotics and the antibiotic resistance genes may cause severe hazards to human health via drinking water. Cultivable bacteria in one of the water supply systems in Shanghai were isolated and identified. The multidrug resistance in drinking water for cultivable bacteria and their change and mechanism in water supply system was analyzed using ampicillin (Amp), kanamycin (Kan), rifampicin (Rif), chloramphenicol (Cm) and streptomycin (Str). The results showed that, the isolated microorganisms mainly belonged to 16 genera.

Hederagenin is an effective constituent of many medical plants, such as Clematidis Radix, and has a wide range of applications in anti-tumor, anti-inflammatory, antidepressant, hepatoprotective antibacterial, et al. In order to obtain the efficient production of yeast cells for hederagenin,we successfully cloned and screened out a P450 gene MdMA02 from Malus×domestica which can catalyze oleanolic acid C-23 oxidation with our developed plug and play platform. Its amino acid homology is only 32% as compared to characterized CYP72A68v2. By transforming MdMA02 to the oleanolic acid-producing strain BY-OA, a hederagenin-producing strain was constructed and hederagenin's titer could achieve 101 mg·L⁻¹ using high cell density fermentation, which was 337 times higher than in shake flasks culturing. This study provides a basis for further research on promoting the creation of oleanane-type pentacyclic triterpenoids biosynthetic pathway analysis and relative cell factories construction.

Nerolidol is an important constituent of terpenoid essential oil and has excellent anti-tumor, anti-bacterial, and anti-oxidative properties. For realizing heterogenous production of nerolidol, our research firstly integrated the codon-optimized Actinidia sinensis nerolidol synthase gene (NES) into the terpenoid chassis strain FPP-001, and obtained NES-001 that could produce 2.71 mg•L⁻¹ nerolidol. Then, the N-terminal of the NES was fused with FPS by linker peptide GGGS. With this strategy, nerolidol production improved by 59.80-fold, reaching 162.07 mg•L⁻¹. Finally, by introduction of auxotrophic marker TRP1 in NES-002, the resulting strain NES-003 could produce 1 711.53 mg•L⁻¹ by high cell density fermentation method. This study provides the basis for the fermentative production of nerolidol and other sesquiterpenoids.

Electrochemically active bacteria (EAB) have attracted great attention in the pollutant biodegradation due to its unique extracellular reduction capacity. But the reduction ability of biogenic electron is insufficient to achieve degradation of many pollutants. Thus, in the present study, Shewanella oneidensis MR-1 was firstly employed to biofabricate visible light-responsive CdS nanocrystals. A bio-photoelectric reductive degradation system (BPRDS) which established by combining S. oneidensis MR-1 and self-synthesized CdS achieved efficient degradation of trypan blue under photoexcitation. Chemical analyses revealed that the cleavage of azo bonds resulted in the decolorization. Blocking of transmembrane electron transfer significantly decreased the decolorization efficiency of BPRDS. After incubating for 5 h, the removal of trypan blue in BPRDS inoculated with ΔmtrA, ΔmtrB, ΔmtrC/omcA, or ΔcymA mutants reduced by 16.46 %, 27.88 %, 25.03 %, and 57.9 %, respectively, compared with wild-type strain inoculated, which indicated that biogenic electron produced by anaerobic respiratory of S. oneidensis MR-1 acted as a hole scavenger and maintained the anaerobic photoexcitation of CdS in BPRDS. Photoexcitation was essential for the BPRDS. This work may provide a new strategy for anaerobic remediation of organic contaminants and be beneficial for the better understanding about anaerobic photodegradation mechanism.

In this paper, Firstly, the follower jamming and the jamming ellipse are introduced; After studying the jamming ellipse and combining the mathematical model of FH signal, the mathematical model of follower jamming is built; the performance of FH communication under the follower jamming is analyzed; Finally, the anti-jamming measures of follower jamming are proposed, In the future research, these can supply the foundation for the feature extraction of the follower jamming identification.

This paper introduces the development of hot-line live working manipulators and gives a new configuration manipulator driven by hydraulic actuator firstly. Then, its forward kinematics equations are derived with homogenous transformation method. Finally, the analytical solutions of its inverse kinematics are solved under the condition that the posture of the end-effector is known and given with z-y-z Euler angles.

The aging and shear rejuvenation behavior of a commercial printing ink have been studied experimentally using creep and oscillation modes. We observed that the printing ink has typical rheological characteristics: time-dependent, reversible and shear-thinning viscosity. Meanwhile, these properties are very strongly influenced by shear history, thus employing pre-shearing to obtain a standard test state is of vital importance. After pre-shearing, the quiescent ink undergoes structural evolution, i.e., aging, including a sol-gel (liquid-solid) transition on the early stage at room temperatures, the higher the temperature, the earlier the sol-gel transition occurs. The degree of aging and shear rejuvenation can be characterized by the waiting time after pre-shearing and the stress dependence of the power-law index. Finally, we use a time-stress superposition to obtain a universal master curve which is able to describe the aging behaviors of the printing ink. This study shows that the aging processes of printing ink for different waiting times are self similar, variation of waiting time just change the time scale and elastic modulus.

The single-layer porous silicon is prepared by electrochemistry etching method, which is used as an immunosensor for determining recombinant mouse zona pellucida 3 fusion protein (r-mZP3) by Raman spectroscopy analysis at room temperature. The molecule binding increases the effective optical thickness (EOT), and thus the Raman spectrum intensity decreases. The concentration and variation of Raman intensity show a good linear quantitative relation. The excellent sensing performance could open the way to a new family of optical sensors for biological standardization.

A series of poly(acrylonitrile-butadiene-styrene) (ABS) grafting modifiers were synthesized by emulsion grafting poly(acrylonitrile-styrene) (SAN) copolymer onto polybutadiene (PB) latex rubber particles. The chain transfer reagent tert-dodecyl mercaptan (TDDM) was used to regulate the grafting degree of ABS and the molecular weight of SAN copolymers. By blending these ABS modifiers with Chlorinated polyvinyl chloride (CPVC) resin, a series of CPVC/ABS blends were obtained. The morphology, compatibility, and the mechanical properties of CPVC/ABS blends were investigated. The scanning electron microscope (SEM) studies showed that the ABS domain all uniformly dispersed in CPVC matrix. Dynamic mechanical analyses (DMA) results showed that the compatibility between CPVC and SAN became enhanced with the TDDM content. From the mechanical properties study of the CPVC/ABS blends, it was revealed that the impact strength first increases and then decreases with the TDDM content, which means that the compatibility between CPVC and the SAN was not the only requirement for maximizing toughness. The decreasing of tensile strength and the elongations might attribute to the lower entanglement between chains of CPVC and SAN. POLYM. ENG. SCI., 52:820-825, 2011. (C) 2011 Society of Plastics Engineers

To clone and express recombinant calpain of Schistosoma japonicum (Sjcalpain), observe the distribution of Sjcalpain in S. japonicum cercariae and analyze its role in skin invasion.The primers were designed according to the full-length sequence of calpain (GenBank accession No. AB016726). The genes encoding catalytic domain and Ca2+ binding domain of Sjcalpain were amplified by PCR, and the target fragments were subcloned into pET-28a. The recombinant proteins were expressed in E. coli BL21 (DE3) and purified by Ni-NTA resin. The rabbit polyclonal antibodies were prepared with the two purified recombinant proteins by immunizing New Zealand white rabbits. ELISA was used to detect the titer of rabbit antiserum. Immunolocalization was used to investigate the distribution of Sjcalpain in S. japonicum cercariae. Cercariae were incubated with specific inhibitor before infection of mice and the worm reduction rate was calculated.The recombinant expression vector Sjcalpain catalytic domain/pET28a and Sjcalpain Ca2+ binding domain/pET28a were constructed and the recombinant proteins were successfully expressed in E. coli BL21 (DE3) (about M(r) 43 000 and M(r) 39 000, respectively). The two target proteins were expressed as inclusion bodies. The purified target proteins were obtained through Ni-NTA affinity purification. ELISA result showed that the titer of prepared rabbit polyclonal antibodies was higher than 1 : 80 000. Immunolocalization study demonstrated that Sjcalpain protein was mainly expressed in the head of cercariae. Inhibition assays suggested that the average number of adult worms in calpain inhibitor-incubation group and control group was 19 and 23, respectively, with a worm reduction rate of 17.4%.Sjcalpain is mainly expressed in the head of S. japonicum cercariae. Inhibition of Sjcalpain could reduce the number of invading cercariae in infected mice, which suggest that Sjcalpain may play a role in skin invasion by cercariae.

To enhance the immunocontraceptive effect of Lagurus lagurus zona pellucida 3 DNA vaccine, and to achieve the prospect of application through the pVAX1-sig-LTB-lZP3-C3d3 different immunity pathway.Two adjuvant molecules were constructed into the recombinant plasmid pVAX1-sig-LTB-lZP3-C3d3 as DNA vaccine which contains Escherichia coli heat-labile enterotoxin B subunit and the molecular adjuvant 3 copies of C3d. The results of RT-PCR and western blot showed that the DNA vaccine was expressed in mRNA and protein level. The female C57BL/6 mice were immunized by three ways: intramuscular injection, intranasal or oral route.Antibody levels and types were detected by ELISA.ELISA results showed that recombinant plasmid pVAX1-sig-LTB-lZP3-C3d3 immunization induced specific IgG, IgA levels were significantly different comparing with control (P0.01). Antifertility experiment showed that the experimental group reduced the average fertility significantly different compared with the control group (P0.01).Restriction analysis, RT-PCR and Western blot showed that the recombinant plasmid constructed correctly and can be the expression of mRNA and protein levels.It resulted that the recombinant plasmid pVAX1-sig-LTB-lZP3-C3d3 can induce the specific immune response efficiently and enhance the immunocontraceptive effects.

Compatibility, morphology structure, and mechanical properties of CPVC/ABS (Chlorinated polyvinyl chloride/acrylonitrile-butadiene-styrene) blends were studied. The core-shell ratios of ABS were set at 40/60 and 70/30. The interface interactions between ABS and CPVC were changed by modifying the acrylonitrile (AN) content of the shell. The compatibility of CPVC with the shell of ABS was studied by the blends of CPVC/SAN with different AN content in SAN. Dynamic mechanical analysis results of CPVC/SAN were in accordance with the morphological properties of CPVC/ABS. The mechanical properties of CPVC/ABS blends in which the polybutadiene content was set to 15 wt % To were studied. Results showed, with the change of AN content, the impact strength followed different way for CPVC/ABS blends with different core-shell ratios of ABS because of the influence of the compatibility. When the core-shell ratio was 40/60, the CPVC/ABS blends were much ductile in more widely AN range than the blends, whereas the core-shell ratio of ABS was 70/30. The differences also showed in the SEM micrographs by the investigation of toughening mechanism. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 116: 3448-3454, 2010

To investigate the effects of CO(2) pneumoperitoneum on blood flow volume of abdominal organs of rabbits with controlled hemorrhagic shock model and liver impact injuries.After controlled hemorrhagic shock and liver impact injuries, the rabbit model was established. Eighteen rabbits subjected to hemorrhagic shock and liver impact injuries were divided into 3 groups randomly according to the volume of lost blood: light hemorrhagic shock (blood loss volume was 10%, 6 ml/kg), moderate hemorrhagic shock (20%, 12 ml/kg) and severe hemorrhagic shock (40%, 22 ml/kg). Intraabdominal pressures of CO(2) pneumoperitoneum was 10 mmHg. Color-labeled microspheres were used to measure the blood flow volume of the liver, kidney and stomach before pneumoperitoneum at 30 minutes and 2 hours after pneumoperitoneum and 30 minutes after deflation. And the mortality and hepatic traumatic condition of rabbits were recorded.Of the 18 rabbits, there were 9 with liver impact injuries at Grade I , 8 at Grade II and 1 at Grade III (according to AIS-2005). The mortality rate in light hemorrhagic shock group was 33.33%, and that in moderate or severe hemorrhagic shock group was 100% within 30 minutes and 2 hours after pneumoperitoneum, respectively. The blood flow volume in the organs detected decreased at 30 minutes under pneumoperitoneum in light and moderate hemorrhagic shock groups. At the same time, the blood flow volume of the liver in moderate hemorrhagic shock group decreased more significantly than that in light hemorrhagic shock group.The blood flow volume of abdominal organs in rabbits is decreased obviously under CO(2) pneumoperitoneum, with fairly high mortality rate. It is believed that CO(2) pneumoperitoneum should cautiously be used in abdominal injury accompanied with hemorrhagic shock, especially under non-resuscitation conditions.

To explore the effects of impact injury of liver on myocardial systolic function and arterial blood gases in rabbits.A model of hepatic impact injury was reproduced in rabbits by hitting the xiphoid area with two falling steel balls. Myocardial systolic function and arterial blood gases were measured respectively before injury, immediately and 0.5, 1, 2 hours after injury, and before the death.After injury, heart rate (HR), left ventricular systolic pressure (LVSP), the maximum change rate of left ventricular pressure rise and fall (+/-dp/dt max) descended significantly, while left ventricular end-diastolic pressure (LVEDP) showed no statistically significant change. At the same time, blood pH and HCO(3)(-) fell gradually, and negative base excess (BEecf) showed a significant increase, indicating metabolic acidosis gradually developed. There was no obvious significant difference in partial pressure of carbon dioxide in artery (PaCO(2)) between the values before and after injury. Partial pressure of oxygen in artery (PaO(2)) decreased gradually, but no significant differences were found between the values of 0.5 hour and 1 hour after injury and that before injury.After hepatic impact injury, myocardial systolic function deteriorates, metabolic acidosis appears.

To summarize the experience of the treatment of traumatic hepatorrhexis.The clinical data of 209 cases of liver trauma treated in the three affiliated hospitals of the Third Military Medical University from 1989 to 1999 were retrospectively analyzed. Among the 209 patients, 108 (51.7%) had Grade III or more severe liver injury. Operative treatment was performed in 186 cases and preservative treatment in 23.In the operated group, 169 patients were cured. The complications occurred in 18 patients and 17 of them died. In the non-operated group, the complications occurred in 22 patients and only 1 of them died.Severe injury and delayed treatment are two major factors leading to death from liver injuries. Surgical intervention is still the principal measure to treat traumatic hepatorrhexis. The indications for non-operative treatment should be carefully selected.

To investigate the role and clinical value of radionuclide imaging in hepatic impact injuries in rabbits.Rabbits were experimentally impacted on the liver with BIM-IV bio-impact machine. Liver imaging was performed with 99mTc labeled sodium phytate. Liver blood pool imaging was performed with 99mTc-stannous pyrophosphate labeled red blood cells. The results of radionuclide imaging were compared with the anatomic results.There was significant difference between the images of the injured liver and the control. Radio diminution and defect were shown in the injured liver areas. Various sorts of abnormal radioactivity distribution were observed with hepatic blood pool imaging. The results of the liver imaging and liver blood pool imaging were accorded with the results of the anatomic findings.Radionuclide imaging may well display the changes of hepatocellular structures and functions after injury, which is valuable in locating the concrete injured position and differentiating the injured degrees of liver.

To investigate the clinical effect of vacuum sealing in treatment of traumatic soft tissue defect.From 1998. 8 to 2001. 2, 49 patients with 55 traumatic soft tissue defects were treated by vacuum sealing after debridement. Among them, there were 39 males and 10 females with mean age 38. 4 years. The wound area varied from 10 cm x 10 cm to 30 cm x 30 cm. In the experimental group, the wound surfaces or cavities were filled with polyvinyl alcohol foams with embedded drainage tubes connected with vacuum bottle (negative pressure of 50-60 kPa). Wound closure was performed with secondary suturing, or skin transplantation, or local flap grafting after 5-7 days. Besides, 126 patients were managed by traditional dressing as the control group.Out of 51 traumatic soft tissue defects (45 patients), the wound closure was performed with a free flap in 4, with local flap in 8, with skin grafting in 27, with secondary suturing in 6, and with vacuum sealing directly in the other 6 defects. Forty-five patients recovered and no complications (systemic and located) occurred. There were significant differences in time of secondary suturing, times of dressing, wound shrink and total therapeutic cost between two groups (P0.01).Vacuum sealing can protect the wound against contamination, evacuate the wound exudates completely, stimulate the growth of granulation tissue, and facilitate the wound healing; so vacuum sealing is a simple and effective method in treatment of traumatic soft tissue defect.