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Surgical resection remains the preferred approach for some patients with glioblastoma (GBM), and eradication of the residual tumour niche after surgical resection is very helpful for prolonging patient survival. However, complete surgical resection of invasive GBM is difficult because of its ambiguous boundary. Herein, a novel targeting material, c(RGDyk)-poloxamer-188, was synthesized by modifying carboxyl-terminated poloxamer-188 with a glioma-targeting cyclopeptide, c(RGDyk). Quantum dots (QDs) as fluorescent probe were encapsulated into the self-assembled c(RGDyk)-poloxamer-188 polymer nanoparticles (NPs) to construct glioma-targeted QDs-c(RGDyk)NP for imaging-guided surgical resection of GBM. QDs-c(RGDyk)NP exhibited a moderate hydrodynamic diameter of 212.4 nm, a negative zeta potential of –10.1 mV and good stability. QDs-c(RGDyk)NP exhibited significantly lower toxicity against PC12 and C6 cells and HUVECs than free QDs. Moreover, in vitro cellular uptake experiments demonstrated that QDs-c(RGDyk)NP specifically targeted C6 cells, making them display strong fluorescence. Combined with ultrasound-targeted microbubble destruction (UTMD), QDs-c(RGDyk)NP specifically accumulated in glioma tissue in orthotropic tumour rats after intravenous administration, evidenced by ex vivo NIR fluorescence imaging of bulk brain and glioma tissue sections. Furthermore, fluorescence imaging with QDs-c(RGDyk)NP guided accurate surgical resection of glioma. Finally, the safety of QDs-c(RGDyk)NP was verified using pathological HE staining. In conclusion, QDs-c(RGDyk)NP may be a potential imaging probe for imaging-guided surgery.

Metal-free carbon nanomaterials have rapidly grown in using as the cathodic oxygen reduction reaction (ORR) catalyst due to their low cost, high electrical conductivity, and great stability. Recent progresses have...

Defects can greatly promote the catalytic activity of a carbon-based electrocatalyst due to charge redistribution of its electroneutral π-conjugated structure. However, it is still a huge challenge to introduce enough defects into carbon-based materials to improve their catalytic activity. Herein, we report a new method for defect generation by the pyrolysis of the sulfur-nitrogen-containing coordination polymer [Zn(ptt)

Controlling interface gas adsorption properties of carbon materials is a prerequisite for exploiting efficient metal-free electrocatalysts but it is usually ignored. Herein, we fabricate a hierarchical porous carbon electrocatalyst with defect (DHPC) by carbon thermal reaction, which shows good CO2RR selectivity and stability. The experimental results indicated that the carbon defect might be the active center for efficient CO2RR performance because it can serve as a Lewis base center and provide an appropriate CO2-chemisorption energy. Moreover, X-ray absorption spectroscopy (XAS) results demonstrated that the carbon defect can induce a reversible carbon–carbon interface with CO2 gas molecule, which would be further strengthened under an applied bias. Besides, the 13CO2 isotope labelling experiment and density functional theory calculations further confirmed that the high CO2RR performance of DHPC comes from its intrinsic defect sites. This study not only provides a new avenue and concept to design CO2RR electrocatalysts but also, to some extent, indicates a possible catalytic mechanism for carbon defect-based electrocatalysts.

The “shuttle effect” of long-chain polysulfides and the low conductivity of elemental sulfur lead to the inferior cycling stability of lithium–sulfur batteries and imped their practical applications. Herein, Co3O4 nanoflakes with uniform macro pores distribution were synthesized via facile oil bath and calcination methods. Coupled with super P and coated on common polypropylene separators, they were expected to hinder the migration of lithium polysulfides (LiPSs) and accelerate the redox kinetics of polysulfides. Coin cells assembled with the Co3O4–super P interlayer exhibited a capacity of 760 mA h g−1 at 1 C, maintained 598 mA h g−1 after 350 cycles, and the decay rate of discharge capacity was only about 0.062% per cycle. Such high performance can be attributed to the synergistic effects between polar Co3O4 and conductive super P. The facile fabrication method and high performance make the Co3O4-super P interlayer a feasible material to apply in lithium-sulfur batteries.

The research of high-performance flexible supercapacitors is urgent due to the rapid development of wearable and portable electronics. The key challenge is the preparation of flexible electrodes with high areal capacitance since electrodes are the most important part of supercapacitors. Compared to those conventional electrodes loading with typical flexible substrates such as textile, PET, paper et al, free-standing electrodes have many advantages such as more efficient capacity contribution, solidly embedded active materials and thinner thickness. Herein, we have successfully fabricated a novel sandwich-like structure free-standing MoO3-rGO (reduced graphene oxide) composite film electrode for flexible supercapacitors using simple vacuum filtration method followed by HI reduction process. The obtained MoO3-rGO composite film electrode shows excellent electrochemical performance, whose areal specific capacitance reaches 8972 mF·cm-2 (1.5 mA·cm-2). Here, MoO3 provides pseudocapacitance and rGO provides double-layer capacitance. After cycling for 2000 cycles, the capacity retention is 86.7%, showing good cycle stability. Besides, the as-prepared composite film has good flexibility and will not break easily during following bending, rolling, folding or twisting steps. This study has been approved to be an important step for the high-performance electrode design for free-standing flexible supercapacitors.

Oxygen vacancy-enriched MoO3−x nanobelts with oxygen vacancies up to 20% (equal to MoO2.4) were synthesized and demonstrated fast reaction kinetics. An asymmetric supercapacitor was assembled with active carbon (AC) as the anode and the as-prepared MoO3−x nanobelts as the cathode. A new aqueous electrolyte of H2SO4/ethylene glycol (EG) was investigated and found to work appropriately at low temperatures, even at −25 °C. The MoO3−x nanobelts electrode possesses excellent specific capacitance, rate capacity (1230 F g−1 and 1220 F g−1 at 5 A g−1 and 50 A g−1, respectively) and cycle performance (100% after 38 000 cycles). Its energy and power densities reached 111 W h kg−1 and 803 W kg−1 or 50 W h kg−1 and 27 321 W kg−1 and maintained 80 W h kg−1 and 794 W kg−1 or 17 W h kg−1 and 23 565 W kg−1 at −25 °C. It is hypothesized that the coexistence of oxygen vacancies and low valence Mo ions enhanced both mass and charge transport kinetics and catalyzed the redox reactions.

In this study, we have proposed an in situ ion regulation strategy to assemble a white-light-emitting material with high stability and efficiency. A fluorescence tunable hybrid material was first fabricated by a “ship around the bottle” method in which the fluorescent dyes, disodium 2-naphthol-3,6-disulfonate (R) and ZnO Quantum Dots (QDs), were embedded into metal–organic frameworks (MOFs) in proportion. Then, the competition coordination of aluminium ions over zinc ions to R were utilized to subtly adjust the intensity of blue fluorescence, leading to an ideal white light with Commission Internationale de l'Eclairage (CIE) coordinates of (0.30, 0.33) and a high Color-Rendering Index (CRI) value of 93%. Compared with the material fabricated by the ratio tuning of the R salt and ZnO QDs directly, the in situ ions regulation strategy enabled the final product to have a higher quantum efficiency and light stability. Moreover, this strategy also settled the non-tunable problem of fluorescence due to the competition coordination effects of aluminium ions and zinc ions in the same synthetic system. This synthetic strategy and our new findings can provide more ideas for designing new white-light-emitting materials.

MoO3−x nanobelts with different concentrations of oxygen vacancies were synthesized by a one-step hydrothermal process. XPS test results show that oxygen vacancies are distributed from the exterior to the interior of the MoO3−x nanobelts. As an anode material for lithium-ion batteries, MoO3−x-10 releases excellent rate capacitance. It can maintain a high specific capacitance of about 500 mA h·g−1 at a high current density of 1000 mA·g−1. In the aspect of cycling stability, MoO3−x-10 can retain a high specific capacity of 641 mA h·g−1 after cycling for 50 times at 100 mA·g−1 and 420 mA h·g−1 after cycling for 100 times at 500 mA·g−1. The coexistence of oxygen vacancies and low-valence Mo ions is conducive to the intercalation/de-intercalation of Li ions and to promoting redox reactions. It has been proved to be a significantly effective way in which oxygen vacancies can improve the integrated performance of MoO3−x nanobelts as anode materials.

3D-networked CNT–Ni3S2–CNT-A supported by Ni foam was rationally designed and synthesized via a multistep transformation approach. The intriguing and individual nanostructures endow the hybrid composites with outstanding electrochemical performance with an areal specific capacitance of 13 400 mF cm−2 at the current density of 10 mA cm−2 and an excellent rate capacity of 96.04% at 50 mA cm−2. The corresponding asymmetric supercapacitor assembled with CNT–Ni3S2–CNT-A (positive electrode) and active carbon (negative electrode) delivered a high energy density of 75.2 W h kg−1 at the power density of 2416 W kg−1, an excellent areal capacitance (425 mF cm−2 at 3 mA cm−2) and electrochemical cycling stability (90.6% retention after 10 000 cycles). The dual function of CNTs is responsible for the impressive electrochemical performance; the inner CNT provides more electrodeposition sites for higher capacitance while the outer high electrical conductivity CNT acts as highways for faster electron transportation. The rational design concept of this work is versatile and scalable for combining transition-metal sulfides with carbon materials for high performance supercapacitors.

To investigate the effects of different crystallinities on the electrochemical performance of V2O5 as an anode material for lithium ion batteries, spherical V2O5 with variable crystallinities was prepared via a solvothermal method and changing the calcination temperature. The results confirmed that V2O5 with lower crystallinity showed a better lithium ion storage performance because of its loose structure, lower polarization, and the convenient diffusion of lithium ions. The reversible specific capacity of V2O5 obtained at 250 °C (1092.1 mA h g−1) with lower crystallinity was much higher than that of the others prepared at 350 °C (645.9 mA h g−1), 450 °C (526 mA h g−1), and 550 °C (498.9 mA h g−1) at 100 mA g−1 after 200 cycles. Also, it maintained a specific capacity of 584.6 mA h g−1 even at 1 A g−1 after 500 cycles. V2O5 prepared at 350 °C exhibited an excellent rate performance with a specific capacity of 131.1 mA h g−1 at a current density of 5 A g−1. The aim of this study was to propose an effective direction and strategy to design traditional metal oxide electrode materials with lower crystallinity to enhance the cycle and rate performance of lithium ion batteries in the future.

The report is about a 49-year-old man with rheumatic heart disease and atrial fibrillation. He underwent mitral valve replacement, tricuspid valvuloplasty, and atrial fibrillation radiofrequency ablation in the hospital. He vomited blood on the 2nd postoperative day, and the bleeding gradually worsened thereafter. He had to have repeated drainage of large amounts of blood from his right thoracic cavity and digestive tract. He died suddenly after undergoing an oesophageal endoscopy on the 24th postoperative day. The autopsy revealed an atrial-oesophageal-thoracic fistula. By excluding the possibility of the fistula being caused by complications from nasoenteric feeding, tracheal intubation, and a foreign body ingestion, we determined that the atrial-oesophageal-thoracic fistula was a complication after radiofrequency ablation according to the finding of coagulation necrosis of the myocardial cells at the left atrium fistula. In addition, we also performed an elemental analysis on the radiofrequency ablation area and other cardiac tissues by scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) and found five metal elements, Cr, Cu, Zn, Mn, and Ti, which specifically existed in the radiofrequency ablation area. This finding has the potential to serve as new evidence for radiofrequency ablation and is a worthy direction of research.

MoO

Chemical-looping combustion (CLC) has been recognized as an energy-efficient method for CO 2 capture. For calcium sulfate (CaSO 4 ) oxygen carrier, the rapid fall in the mechanical strength and reactivity limits its application in CLC. In this study, Taguchi robust design method with L 9 orthogonal array was implemented to optimize extrusion condition for the preparation of binder-supported CaSO 4 oxygen carriers. The orthogonal experiment results showed the addition of SB powder enhanced both mechanical strength and conversion of CaSO 4 , and the optimal extrusion condition was 30 g CaSO 4 , 12 g SB powder, 2.5 mL acetic acid, and 15 mL water. The favorable oxygen carriers were comprehensively studied in a fixed bed reactor. The results of reduction test showed the mass-based reaction rates of the binder-supported CaSO 4 were significantly increased, because the fresh samples had the higher surface area which was evidenced by pore structure analysis. Moreover, the favorable performance of binder-supported CaSO 4 was explained by formation of CaAl 2 O 4 which had excellent thermal stability and provided a stable nanosized framework between the crystal grains observed by field emission scanning electron microscope (FESEM).

Multi-cyclic CaO carbonation/calcination is an attractive method for CO 2 capture during coal combustion. However, the capture capacity of CaO sharply decreases with increasing carbonation/calcination cycles. In order to improve the stability of CO 2 capture capacity of CaO during carbonation/calcination cycles, synthetic CaO/Al 2 O 3 sorbents were synthesized by two methods: wet chemistry and sol–gel-combustion-synthesis (SGCS) to make a further comparison. The results indicate that the SGCS-made CaO/Al 2 O 3 = 80:20 wt% sorbent provides a competitive performance of a capture capacity of 0.43 g-CO 2 /g-sorbent after 20 cycles.

In this study chemical-looping combustion of methane with compound CaSO 4 oxygen carrier prepared by impregnation method was investigated in a fixed bed reactor. The effects of reaction temperature, CH 4 percent, particle size and sample mass on reduction were discussed and an appropriate condition was determined by contrastive experiments. The results show that Ni-Fe mixed additive greatly improves the reactivity of CaSO 4 , and the suitable reaction temperature is around 925°C. Carbon deposition is inhibited and higher gas conversion is obtained by lower CH 4 percent and more sample mass. However, the sample particle size has a little effect on the reduction. The long-time reduction-oxidation test demonstrates that compound CaSO 4 oxygen carrier has a higher conversion. X-ray diffraction analysis reveals that CaSO 4 could be fully reduced into CaS which is also almost oxidized into CaSO 4 .

The calcium looping cycles method has been identified as an attractive method for CO2 capture during coal combustion and gasification processes. However, it is well-known that the capture capacity of CaO undergoes a rapid decrease after mutiple cycles. In order to improve the stability of CO2 capture capacity in CaO, this paper focuses on the development and performance of the synthetic CaO/La2O3 sorbents for calcium looping cycles.The sorbents were synthesized by three different methods: dry physical mixing, wet chemistry, and sol−gel combustion synthesis (SGCS). Their multicyclic CO2 capture capacity and the effect of the additive La2O3 were investigated in a fixed bed reactor system. The results indicate that the additive of La2O3 plays a positive role in the carbonation/calcination reactions, and the SGCS-made synthetic sorbent is composed of ultrafine well-dispersed hollow structured particles which are beneficial to the gas-phase diffusion on the surface area and can prevent small CaO particles from...

Pregnancy-associated plasma protein-A (PAPP-A) is a metalloprotease that cleaves insulin-like growth factor-binding proteins (IGFBPs) to release bioactive levels of free insulin-like growth factor. Specific and potent inhibitors of PAPP-A may further elucidate the biological functions of this protease and could prove to be of therapeutic value. Phage display was used to discover fully human antibody inhibitors of PAPP-A activity towards IGFBP4 cleavage. Estimates of the inhibition constants for these antibodies were subsequently determined using a novel continuous assay of PAPP-A protease activity that uses an internally quenched synthetic peptide substrate (DX-1655). DX-1655 was hydrolyzed by PAPP-A with a K m of 33 μM and a k cat of 0.3 s-1 (k cat/K m=9.1×103 M-1 s-1). PAPP-A activity towards DX-1655 displays a bell-shaped pH profile, with pK a values of 8.2 and 10.8 and a maximum rate at approximately pH 9.5. Using this continuous assay, we measured apparent K i values of 1.7±0.2 and 7.4±1.5 nM for the F2 and D9 antibodies, respectively.

Linking magnetically frustrated triangular FeO units by divalent metal ions (M(II) = Fe(II) for 1, Mn(II) for 2) gives isostructural 1D spin chains. Strong antiferromagnetic interactions were found in these complexes with significant frustrations but very interesting ferrimagnetic like transition and metamagnetism were found in mixed valence 1. By comparing the magnetic behaviours with isostructural complex 3 (with M(II) = Mg(II)), it is proposed that the spins of Fe(II) ions and Mn(II) ions have ferromagnetic and antiferromagnetic contributions respectively.

The extracytoplasmic function (ECF) sigma factors constitute a diverse group of alternative sigma factors that have been demonstrated to regulate gene expression in response to environmental conditions in several bacterial species. Genes encoding an ECF sigma factor of Mycobacterium tuberculosis, Mycobacterium avium, and Mycobacterium smegmatis, designated sigE, were cloned and analyzed. Southern blot analysis demonstrated the presence of a single copy of this gene in these species and in Mycobacterium bovis BCG, Mycobacterium leprae, and Mycobacterium fortuitum. Sequence analysis showed the sigE gene to be highly conserved among M. tuberculosis, M. avium, M. smegmatis, and M. leprae. Recombinant M. tuberculosis SigE, when combined with core RNA polymerase from M. smegmatis, reconstituted specific RNA polymerase activity on sigE in vitro, demonstrating that this gene encodes a functional sigma factor. Two in vivo transcription start sites for sigE were also identified in M. smegmatis and M. bovis BCG. Comparison of wild-type M. smegmatis with a sigE mutant strain demonstrated decreased survival of the mutant under conditions of high-temperature heat shock, acidic pH, exposure to detergent, and oxidative stress. An inducible protective response to oxidative stress present in the wild type was absent in the mutant. The mycobacterial SigE protein, although nonessential for viability in vitro, appears to play a role in the ability of these organisms to withstand a variety of stresses.

The recognition of lysosomal enzymes by UDP-GlcNAc: lysosomal-enzyme GlcNAc-1-phosphotransferase (phosphotransferase) is mediated by a protein structure on lysosomal enzymes. It has been previously demonstrated that lysine residues are required for phosphorylation of procathepsin L and are a common feature of the site on many lysosomal proteins. In this work, the procathepsin L recognition structure was further defined by identification of the region of the protein containing the structure and the critical lysine residues involved. Removal of the cathepsin L propeptide by low pH-induced autocatalytic processing abolished phosphorylation. The addition of either the purified propeptide or a glutathione S-transferase-propeptide fusion protein to the processed protein restored phosphorylation. Mutagenesis of individual lysine residues demonstrated that two propeptide lysine residues (Lys-54 and Lys-99) were required for efficient phosphorylation of procathepsin L. By comparison of the phosphorylation rates of procathepsin L, lysine-modified procathepsin L, and the procathepsin L oligosaccharide, lysine residues were shown to account for most, if not all, of the protein-dependent interaction. On this basis, it is concluded that the proregion lysine residues are the major elements of the procathepsin L recognition site. In addition, lysine residues in cathepsin D were shown to be as important for phosphorylation as those in procathepsin L, supporting a general model of the recognition site as a specific three-dimensional arrangement of lysine residues exposed on the surface of lysosomal proteins.

Troponin T (TpnT), an essential component of the Ca(2+)-regulatory troponin complex, is involved in protein-protein interactions with other thin-filament proteins during muscle contraction in vertebrate striated muscle (VSM). The isoforms of TpnT are encoded by members of a multigene family which, by alternate splicing, produces a complex pattern of isoproteins in VSM. The functional domains of TpnT are only tentatively identified and structure-function analysis on this protein is limited due to the heterogeneity of the multiple isoforms. We reasoned that the overproduction and purification of a single TpnT species in Escherichia coli would provide an insight into these studies, besides being useful in crystallizing the protein. We cloned the human fast skeletal beta TpnT-encoding cDNA (beta TpnTf) in three expression vectors. Overexpression was achieved in an E. coli BL21 (DE3) lysogen using a T7 RNA polymerase promoter-based vector, pET17b. The unfused recombinant protein was purified by a simple and rapid procedure in a biologically active and immunoreactive form. This is the first successful synthesis of a complete beta TpnTf polypeptide from any species using an in vitro expression system. Purified human beta TpnTf, a predominant fetal form, was less Ca(2+)-sensitive and exhibited considerably reduced affinity for troponin C and tropomyosin, as compared to the rabbit fast skeletal alpha TpnT, a predominant adult isoform. These results provide a biochemical correlate to the age-related differences in Ca2+ sensitivity of tension development in vertebrate fast skeletal muscles.

To investigate the role of the proregion in the biosynthesis and trafficking of mouse cathepsin L, cathepsin L cDNAs encoding proteins with altered proregions were constructed and their expression in COS cells was examined, As in transformed cells, normal mouse cathepsin L was secreted by COS-cells. In contrast, two altered proregion cathepsin L proteins, one in which the proregion was deleted and a second in which the proregion was replaced with that of a homologous protein (aleurain), were retained within the cell and degraded over a period of 2-6 h. Immunofluorescence localization and the lack. of effect of NH4Cl and brefeldin A on the turnover of the altered cathepsin L proteins indicated that their degradation occurred in the endoplasmic reticulum (ER). By using brefeldin A to induce colocalization of the UDPGlcNAc: lysosomal enzyme N-acetylglucosamine-1-phosphotransferase with the cathepsin L proteins in the ER, it was shown that the altered proteins were not susceptible to mannose phosphorylation as they exist in the ER. Trypsin sensitivity assays indicated that altered proregion proteins synthesized in COS cells or in vitro are misfolded. Taken together, these results indicate that the proregion plays an essential role in proper folding of cathepsin L. ER retention, decreased stability, and lack of mannose phosphorylation of the altered proteins are most likely secondary effects resulting from improper folding.

A cDNA encoding human fast skeletal beta troponin T (beta TnTf) has been isolated and characterized from a fetal skeletal muscle library. The cDNA insert is 1,000 bp in length and contains the entire coding region of 777 bp and 5' and 3' untranslated (UT) segments of 12 and 211 bp, respectively. The 3' UT segment shows the predicted stem-loop structure typical of eukaryotic mRNAs. The cDNA-derived amino acid sequence is the first available sequence for human beta TnTf protein. It is encoded by a single-copy gene that is expressed in a tissue-specific manner in fetal and adult fast skeletal muscles. Although the human beta TnTf represents the major fetal isoform, the sequence information indicates that this cDNA and the coded protein are quite distinct from the fetal and neonatal TnTf isoforms reported in other mammalian fetal muscles. The hydropathy plot indicates that human beta TnTf is highly hydrophilic along its entire length. The protein has an extremely high degree of predicted alpha-helical content involving the entire molecule except the carboxy-terminal 30 residues. Comparative sequence analysis reveals that the human beta TnTf shares a high level of sequence similarity in the coding region with other vertebrate TnTf and considerably reduced similarity with slow skeletal and cardiac TnT cDNAs. The TnT isoforms have a large central region consisting of amino acid residues 46-204 which shows a high sequence conservation both at the nucleotide and amino acid levels. This conserved region is flanked by the variable carboxy-terminal and an extremely variable amino-terminal segment. The tropomyosin-binding peptide of TnT, which is represented by amino acid residues 47-151 and also includes a part of troponin I binding region, is an important domain of this central segment. It is suggested that this conserved segment is encoded by an ancestral gene. The variable regions of vertebrate striated TnT isoforms reflect the subsequent addition and modification of genomic sequences to give rise to members of the TnT multigene family.

A method was developed to rapidly identify high-affinity human antibodies from phage display library selection outputs. It combines high-throughput Fab fragment expression and purification with surface plasmon resonance (SPR) microarrays to determine kinetic constants (kon and koff) for 96 different Fab fragments in a single experiment. Fabs against human tissue kallikrein 1 (hK1, KLK1 gene product) were discovered by phage display, expressed in Escherichia coli in batches of 96, and purified using protein A PhyTip columns. Kinetic constants were obtained for 191 unique anti-hK1 Fabs using the Flexchip SPR microarray device. The highest affinity Fabs discovered had dissociation constants of less than 1 nM. The described SPR method was also used to categorize Fabs according to their ability to recognize an apparent active site epitope. The ability to rapidly determine the affinities of hundreds of antibodies significantly accelerates the discovery of high-affinity antibody leads.

To explore the correlation of the ultrasound indices of liver and spleen in schistosomiasis japonica and with infection frequency, infection time and EPG.The canonical correlation was applied to analyze the correlation of the hepatosplenic ultrasound indices in schistosomiasis japonica, and the correlation of the ultrasound indices with infection frequency, infection time and EPG. The proportions of variation related to each other in liver and spleen were analyzed by the redundancy analysis.The correlation coefficients of the first pair correlation canonical variable were 0.7842, 0.5483 and 0.5800, 0.4220, respectively, in males and females without infection, males and females with infection history (P0.01). The correlation coefficients of the first pair correlation canonical variable were 0.6063, 0.5215 and 0.6595, 0.3849, respectively, in male negatives and female negatives, male positives and female positives (P0.01). In groups of males and females without infection, the variations of liver ultrasound indices related with the variation of spleen ultrasound indices were 43.5% and 17.5% respectively, and in groups infection history, they were 22.1% and 11.4% respectively. In male and female negative groups, the variations of liver ultrasound indices related with the variation of spleen ultrasound indices were 26.8% and 16.8% respectively, and in positive groups, they were 27.6% and 10.7% respectively. The infection frequency, infection time and EPG in the stool-positive groups were not significantly related with the canonical variables of liver and spleen ultrasound indices (P0.05).There is a significant canonical correlation between the liver and spleen ultrasound indices in schistosomiasis japonica, especially in males. In groups with infection history, the infection frequency, infection time and EPG of those stool-positives are not relevant to the canonical variables of liver and spleen ultrasound indices.

Polypeptides for use in affinity chromatography of factor VIII were identified using phage display technology. Phage libraries were designed to express polypeptide fusions containing five to seven residues flanked by two cysteines that form a disulfide bond. Individual bacteriophage were selected for the ability of these polypeptides to bind factor VIII, and then release the protein under mild elution conditions. Strong consensus sequences were observed that appear to be necessary for this reversible interaction. Chemically synthesized ligands identified by this screening were immobilized onto a chromatographic support and used for affinity purification of factor VIII from a complex feedstream. A chromatographic step was developed that provided a 10000-fold reduction in host cell proteins and DNA, while providing exceptional product recovery.

To explore the synthetical index for diagnosing schistosomiasis with ultrasound and to assess the prevalence rate with the index.Ultrasound indexes of schistosomiasis Japonicum were analyzed by principal component analysis, and the synthetical indexes were assessed by ROC curve.Among the abnormal rates of the 6 indexes, the lowest was 1.6% comparing with the highest of 59.5%. Significant difference was noficed among the abnormal rates (chi(2) = 631.1, P0.01). The individual correlation of the six indexes to each other as will as with age distribution was significant (P0.05). The three principal components reflected the degree of pathological changes on liver and spleen. The first principal component was the factor reflecting the degree of liver pathological changes, and the second and third principal components reflected the degree of pathological changes on spleen. The synthetical index D(1) = 0.047X(1) + 0.428X(2) + 1.247X(3) + 0.095X(4) + 0.002X(5) + 0.213X(6) - 12.837 was found by adding the three weight principal components, and it's area under the ROC curve was 0.957. When -1.70 was taken as the critical value, the abnormal rate of population was 66.3%, close to the resident's actual prevalence rate 66.9%.Ultrasonography was considered as a method which could rapidly assessing the resident's prevalence rate in the endemic areas of schisitosomiasis Japonicum, and could also provide powerful information for development of strategy on chemotherapy.

Extracytoplasmic function (ECF) sigma factors are a heterogeneous group of alternative sigma factors that regulate gene expression in response to a variety of conditions, including stress. We previously characterized a mycobacterial ECF sigma factor, SigE, that contributes to survival following several distinct stresses. A gene encoding a closely related sigma factor, sigH , was cloned from Mycobacterium tuberculosis and Mycobacterium smegmatis . A single copy of this gene is present in these and other fast- and slow-growing mycobacteria, including M. fortuitum and M. avium . While the M. tuberculosis and M. smegmatis sigH genes encode highly similar proteins, there are multiple differences in adjacent genes. The single in vivo transcriptional start site identified in M. smegmatis and one of two identified in M. bovis BCG were found to have −35 promoter sequences that match the ECF-dependent −35 promoter consensus. Expression from these promoters was strongly induced by 50°C heat shock. In comparison to the wild type, an M. smegmatis sigH mutant was found to be more susceptible to cumene hydroperoxide stress but to be similar in logarithmic growth, stationary-phase survival, and survival following several other stresses. Survival of an M. smegmatis sigH sigE double mutant was found to be markedly decreased following 53°C heat shock and following exposure to cumene hydroperoxide. Expression of the second gene in the sigH operon is required for complementation of the sigH stress phenotypes. SigH is an alternative sigma factor that plays a role in the mycobacterial stress response.

Oxygen sensitivity of the nifLA promoter of Klebsiella pneumoniae has been demonstrated. Studies on the oxygen regulation of nifB-lacZ and nifH-lacZ fusions in the presence of the nifLA operon, which contains either an intact or a deleted nifL gene, indicate that possibly both the nifL promoter and the nifL product are responsible for nif repression by oxygen.

An open reading frame upstream from nifHDK operon of Klebsiella pneumoniae had been described. The orientation of this open reading frame is opposite to that of nifHDK and sequence homology was found between the open reading frame promoter and the promoter of nifHDK operon. A recombinant plasmid carrying the promoter region of the open reading frame fused to the beta-galactosidase gene was constructed. Strains of E.coli were transformed with the plasmid containing this open reading frame promoter-lacZ fusion or co-transformed with it and a plasmid carrying the nifA gene. An appreciable activity of beta-galactosidase was found in strains which received both plasmids, indicating that the promoter of the open reading frame can be activated by the product of nifA gene. Thus, the open reading frame found between nifHDK operon and nifJ behaves just like other nif genes of K.pneumoniae in requiring the product of nifA as the positive effector for expression.