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Complexation of dysprosium(III) with the heterodonor chelating ligand o-vanillin picolinoylhydrazone (H2ovph) in the presence of a carbonato ligand affords two novel Dy6 and Dy8 clusters, namely, [Dy6(ovph)4(Hpvph)2Cl4(H2O)2(CO3)2]·CH3OH·H2O·CH3CN (2) and [Dy8(ovph)8(CO3)4(H2O)8]·12CH3CN·6H2O (3). Compound 2 is composed of three petals of the Dy2 units linked by two carbonato ligands, forming a triangular prism arrangement, while compound 3 possesses an octanuclear core with an unprecedented tub conformation, in which Dy(ovph) fragments are attached to the sides of the carbonato core. The static and dynamic magnetic properties are reported and discussed. In the Dy6 aggregate, three Dy2 "skeletons", having been well preserved (see the scheme), contribute to the single-molecule-magnet behavior with a relatively slow tunneling rate, while the Dy8 cluster only exhibits a rather small relaxation barrier [ABSTRACT FROM AUTHOR]

Complexation of dysprosium(III) with the heterodonor chelating ligand o-vanillin picolinoylhydrazone (H2ovph) in the presence of different bases affords three new dinuclear dysprosium(III) coordination compounds, namely, [Dy2(ovph)2(NO3)2(H2O)2]·2H2O (1), [Dy2(Hovph)(ovph)(NO3)2(H2O)4]·NO3·2CH3OH·3H2O (2), and Na[Dy2(Hovph)2(μ2-OH)(OH)(H2O)5]·3Cl·3H2O (3), where the aroylhydrazone ligand adopts different coordination modes in respective structures depending on the reaction conditions, as revealed by single-crystal X-ray analyses to be due to their tautomeric maneuver. The magnetic properties of 1-3 are drastically distinct. Compounds 1 and 2 show single-molecule-magnet behavior, while no out-of-phase alternating-current signal is noticed for 3. The structural differences induced by the different coordinate fashions of the ligand may influence the strength of the local crystal field, the magnetic interactions between metal centers, and the local tensor of anisotropy on each Dy site and their relative orientations, therefore generating dissimilar dynamic magnetic behavior. [ABSTRACT FROM AUTHOR]

A variety of chiral bisphosphoric acids derived from binaphthols have been evaluated for enantioselective 1,3dipolar cycloaddition reactions, revealing that the feature of the linker in the catalysts exerted great impact on the stereoselectivity. Among them, the oxygen-linked bisphosphoric acid la provided the highest level of stereoselectivity for the 1,3-dipolar cyclo addition reaction tolerating a wide range of substrates induding azomethine ylides, generated in situ from a broad scope of aldehydes and ct-amino esters, and various electrondeficient dipolarophiles such as maleates, fumarates, vinyl ketones, and esters. This reaction actually represents one of the most enantioselective catalytic approaches to access structurally diverse pyrrolidines with excellent optical purity. Theoretical calculations with 1.)~ I metnoa on me iormauon ui azunleuuIlc ylides and on the transition states of the 1,3-dipolar cycloaddition step showed that the dipole and dipolarophile were simultaneously activated by the bifunctional chiral bisphosphoric acids through the formation of hydrogen bonds. The effect of the bisphosphoric acids on reactivity and stereochemistry of the three-component 1,3-dipolar cycloaddition reaction was also theoretically rationalized. The bisphosphoric acid catalyst la may take on a half-moon shape with the two phosphoric acid groups forming two intramolecular hydrogen bonds. In the case of maleates, one phosphate acts as a base to activate the 1,3-dipole, and simultaneously, the two hydroxyl groups in the catalyst la may respectively form two hydrogen bonds with the two ester groups of maleate to make it more electronically deficient as a much stronger dipolarophile to participate in a concerted 1,3-dipolar cycloaddition with azomethine ylide. However, in the cases involving acrylate and fumarate dipolarophiles, only one hydroxyl group forms a hydrogen bond with the ester functional group to lower the LUMO of the C-C double bond and another one is remained to adjust the acidity and basicity of two phosphoric acids to activate the dipole and dipolarophile more effectively. [ABSTRACT FROM AUTHOR]

Palm-print image is often influenced by illumination and the arch of the palm-print results in a great deal of noise during the course of palm-print image acquisition. This article presents palm-print recognition based on cross-band fusion by energy weight and comprehensively takes into account the noisy properties of various sub-bands in single wavelet level and decomposition coefficient of the adjacent sub-band, thus the method of energy weight based on palm-print image is employed. Then two-dimensional principal component analysis (2DPCA) is employed for dimension reduction and decorrelated. Finally, a nearest neighbor classifier is used for palm-print recognition. Experimental results on Hong Kong PolyU palm-print database show that correct recognition rate can reach 100% by the method presented within this article. Correct recognition rate and recognition efficiency is higher than that of 2DPCA and WT + DCT + 2DPCA (Wavelet Transform, Discrete Cosine Transform and 2DPCA, WT + DCT + 2DPCA). © 2009 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 19, 350–355, 2009 [ABSTRACT FROM AUTHOR]

Organocatalytic enantioselective Biginelli and Biginelli-like reactions by chiral phosphoric acids derived from 3,3'-disubstituted binaphthols have been investigated. The size of 3,3'-substituents of the catalysts is able to control the stereochemistry of the Biginelli reaction. By tuning the 3,3'-disubstituents of the phosphoric acids, the stereochemistry of the Biginelli reaction can be reversed. This organocatalytic Biginelli reaction by Bronsted acids 12b and 13 is applicable to a wide range of aldehydes and various β-keto esters, providing a highly enantioselective method to access DHPMs. 3,3'-Di(triphenylsilyl) binaphthol-derived phosphoric acid afforded Biginelli-like reactions of a broad scope of aldehydes and enolizable ketones with benzylthiourea, giving structurally diverse dihydropyrimidinethiones with excellent optical purity. Theoretical calculations with the ONIOM method on the transition states of the stereogenic center forming step showed that the imine and enol were simultaneously activated by the bifunctional chiral phosphoric acid through formation of hydrogen bonds. The effect of the 3,3'-substituents in phosphoric acids on the stereochemistry of the Biginelli reaction was also theoretically rationalized. The current protocol has been applied to the synthesis of some pharmaceutically interesting compounds and intermediates, such as chiral thioureas, dihydropyrimidines, guanidines, and the precursor of (S)-L-771 688. [ABSTRACT FROM AUTHOR]

The privileged spiro[pyrrolidin-3,3′-oxindole] derivatives exhibit important biological activities. An enantioselective organocatalytic approach to the rapid synthesis of spiro[pyrrolidin-3,3′-oxindole] derivatives with high enantiopurity and structural diversity is described. The asymmetric catalytic three-component 1 ,3-dipolar cycloaddition of a broad range of methyleneindolinones with aldehydes and amino esters in the presence of chiral phosphoric acid provides spirooxindole derivatives in high yield with unusual regiochemistry and excellent stereoselectivities (up to 98% ee) under mild conditions. The straightforward construction of spirooxindole skeletons with high stereo- and regioselectivity suggests a new avenue to medicinal chemistry and diversity-oriented synthesis. Theoretical calculations disclosed that both the azomethine ylide and the methyleneindolinone are hydrogen-bonded with the phosphoric acid, which accounted for the high enantio- and regioselectivity and indicated that the unusual regioselectivity results from the stabilization stemming from the favorable π-π-v stacking interaction between the oxo-indole ring and the conjugated esters. [ABSTRACT FROM AUTHOR]

The article discusses the crystal structure of nickel and zinc complexes with a monodentate heterocycle and tridentate Schiff base ligands and the self-assembly of both metal-organic compounds to one- and two-dimensional supramolecular networks via morpholine hydrogen bonds. It describes the coordination of nickel ion via phenolate O1, carboxyl O4 and hydrazone N2 atoms forming chelating ring. It shows the probability displacement ellipsoids with atomic numbering consisting of binuclear entity and bridging of phenolate O atoms with zinc ions and bonds.

A chiral Brønsted acid catalyzed 1,3-dipolar cycloaddition reaction directly assembles aldehydes, amino esters, and anilines into synthetically useful chiral imidazolidines with high levels of stereoselectivity (up to 91/9 dr and 98% ee). [ABSTRACT FROM AUTHOR]

The genome of environmental Bacillus amyloliquefaciens FZB42 harbors numerous gene clusters involved in synthesis of antifungal and antibacterial acting secondary metabolites. Five gene clusters, srf, bmy, fen, nrs, dhb, covering altogether 137 kb, direct non-ribosomal synthesis of the cyclic lipopeptides surfactin, bacillomycin, fengycin, an unknown peptide, and the iron siderophore bacillibactin. Bacillomycin and fengycin were shown to act against phytopathogenic fungi in a synergistic manner. Three gene clusters, mln, bae, and dif, with a total length of 199 kb were shown to direct synthesis of the antibacterial acting polyketides macrolactin, bacillaene, and difficidin. Both, non-ribosomal synthesis of cyclic lipopeptides and synthesis of polyketides are dependent on the presence of a functional sfp gene product, 4′-phosphopantetheinyl transferase, as evidenced by knockout mutation of the sfp gene resulting in complete absence of all those eight compounds. In addition, here we present evidence that a gene cluster encoding enzymes involved in synthesis and export of the antibacterial acting dipeptide bacilysin is also functional in FZB42. In summary, environmental FZB42 devoted about 340 kb, corresponding to 8.5% of its total genetic capacity, to synthesis of secondary metabolites useful to cope with other competing microorganisms present in the plant rhizosphere. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Recent year some members of mammalian chitinases and chitinase-like proteins have been discovered, but rat counterpart of human and mouse chitotriosidase has not been identified. Moreover, the physiological functions of mammalian chitinases are not very clear. To facilitate the studies we cloned the cDNA encodes the rat chitotriosidase. The results revealed that it is differ from mouse and human chitotriosidase genes, it exist alternative splicing transcripts in several tissues we detected due to different transcriptional initiation sites and different exon usage, although all the open reading frame of these cDNAs predict a protein of 464 amino acids with a typical chitinase structure, including a signal peptide, a highly conserved catalytical domain and a chitin-binding structure. The predicted amino acid sequence is highly homologous to that of mouse and human chitotriosidase. Recombinant expression of the cloned cDNA demonstrated that the encoded protein is secreted extracellular and has chitinolytic activity. [ABSTRACT FROM AUTHOR]

The functionalization with formaldehyde via an electrophilic substitution reaction and graft with poly (acrylic acid) (PAA) by “grafting from” technology have been carried out for multiwalled carbon nanotubes (MWNTs) and MWNTs-PAA composites have been formed. The IR and TEM results show presence of covalent band and so-called “core-shell” structures for MWNTs-PAA. The MWNTs-PAA exhibits excellent suspendability in water, which is significant to explore the potential application of carbon nanotube in biological and medical systems. [ABSTRACT FROM AUTHOR]

Environmental strain Bacillus amyloliquefaciens FZB42 differs from the domesticated model organism of the same genus, Bacillus subtilis 168, in its ability to promote plant growth and suppress plant-pathogenic organisms present in the rhizosphere. This behavior is exerted mainly through the production of several nonribosomal cyclic lipopeptides and polyketides, which exhibit a broad range of action against phytopathogenic bacteria, fungi, and nematodes. Here, we provide evidence that the synthesis of the main antifungal agent of B. amyloliquefaciens FZB42, bacillomycin D, is regulated in multiple layers. Expression of the bacillomycin D operon (bmy) is dependent on a single σA-dependent promoter, Pbmy and is favored in its natural host by the small regulatory protein DegQ. The global regulators DegU and ComA are required for the full transcriptional activation of bmy. DegU retains a key role since it binds directly to two sites located upstream of the bacillomycin D promoter. Moreover, both DegU and a transmembrane protein of unknown function, YczE, act on a later level of gene expression, exerting their posttranscriptional effects in a hitherto-unknown manner. [ABSTRACT FROM AUTHOR]

Bacillus amyloliquefaciens FZB42 is a Gram-positive, plant-associated bacterium, which stimulates plant growth and produces secondary metabolites that suppress soil-borne plant pathogens. Its 3,918-kb genome, containing an estimated 3,693 protein-coding sequences, lacks extended phage insertions, which occur ubiquitously in the closely related Bacillus subtilis 168 genome. The B. amyloliquefaciens FZB42 genome reveals an unexpected potential to produce secondary metabolites, including the polyketides bacillaene and difficidin. More than 8.5% of the genome is devoted to synthesizing antibiotics and siderophores by pathways not involving ribosomes. Besides five gene clusters, known from B. subtilis to mediate nonribosomal synthesis of secondary metabolites, we identified four giant gene clusters absent in B. subtilis 168. The pks2 gene cluster encodes the components to synthesize the macrolactin core skeleton. [ABSTRACT FROM AUTHOR]

The Bacillus subtilis genome comprises two paralogous single-stranded DNA binding protein (SSB) genes, ssb and ywpH, which show distinct expression patterns. The main ssb gene is strongly expressed during exponential growth and is coregulated with genes encoding the ribosomal proteins S6 and S18. The gene organization rpsF-ssb-rpsR as observed in B. subtilis is found in many gram-positive as well as some gram-negative bacteria, but not in Escherichia coli. The ssb gene is essential for cell viability, and like other SSBs its expression is elevated during SOS response. In contrast, the paralogous ywpH gene is transcribed from its own promoter at the onset of stationary phase in minimal medium only. Its expression is ComK dependent and its gene product is required for optimal natural transformation. [ABSTRACT FROM AUTHOR]

There are two crystallographically independent mol­ecules in the asymmetric unit of the title compound, [Co(C15H12N2O3)(C5H7O2)(C3H7NO)]. The CoIII atom is coordinated by one phenolate O atom, one carbonyl O atom and one hydrazine N atom from the dianionic hydrazone ligand L2−, two O atoms from the acetyl­acetonate anion, and one O atom from the coordinated dimethyl­formamide mol­ecule, to form an elong­ated octa­hedron. The dianionic ligand L2− is not planar. [ABSTRACT FROM AUTHOR]

The article presents a study which showed the recognition of three-component 1,3-dipolar cycloaddition between aldehydes, amino esters, and electron-deficient olefins using the chiral Brønsted acid activated dipole for stereochemistry control. To validate their hypothesis, researchers conducted a three-component reaction of para-nitrobenzaldehyde (3a) and diethyl aminomalonate (4a) with dimethyl maleate before evaluating a number of phosphoric acids. Results of the study are offered.

The article discusses the organocatalytic highly enantioselective Biginelli reaction. The researchers cites that the optimal chiral phosphoric acid, gained from H8-binol, opened the reaction in high yields with outstanding enantioselectivities of up to 97% ee. Substrates, including aldehydes and ß-keto esters, can be tolerated. Such reaction can prevent contamination of transition metals in the fabrication of the medicinally relevant chiral 3,4-dihydropyrimidin-2-(1H)-ones.

The title compound [alternatively called ( E)-3-phenylprop-2-enal azine], C18H16N2, was synthesized by the reaction of hydrocinnamaldehyde with hydrazine hydrate. The nearly planar molecule is centrosymmetric, with the mid-point of the N—N bond lying at an inversion center. [ABSTRACT FROM AUTHOR]

Although bacterial polyketides are of considerable biomedical interest, the molecular biology of polyketide biosynthesis in Bacillus spp., one of the richest bacterial sources of bioactive natural products, remains largely unexplored. Here we assign for the first time complete polyketide synthase (PKS) gene clusters to Bacillus antibiotics. Three giant modular PKS systems of the trans-acyltransferase type were identified in Bacillus amyloliquefaciens FZB 42. One of them, pks1, is an ortholog of the pksX operon with a previously unknown function in the sequenced model strain Bacillus subtilis 168, while the pks2 and pks3 clusters are novel gene clusters. Cassette mutagenesis combined with advanced mass spectrometric techniques such as matrix-assisted laser desorption ionization-time of flight mass spectrometry and liquid chromatography-electrospray ionization mass spectrometry revealed that the pks1 (bae) and pks3 (dif) gene clusters encode the biosynthesis of the polyene antibiotics bacillaene and difficidin or oxydifficidin, respectively. In addition, B. subtilis OKB105 (pheA sfp0), a transformant of the B. subtilis 168 derivative JH642, was shown to produce bacillaene, demonstrating that the pksX gene cluster directs the synthesis of that polyketide. [ABSTRACT FROM AUTHOR]

Xylanases are crucial for lignocellulosic biomass deconstruction and generally contain noncatalytic carbohydrate-binding modules (CBMs) accessing recalcitrant polymers. Understanding how multimodular enzymes assemble can benefit protein engineering by aiming at accommodating various environmental conditions. Two multimodular xylanases, XynA and XynB, which belong to glycoside hydrolase families 11 (GH11) and GH10, respectively, have been identified from Caldicellulosiruptor sp. strain F32. In this study, both xylanases and their truncated mutants were overexpressed in Escherichia coli, purified, and characterized. GH11 XynATM1 lacking CBM exhibited a considerable improvement in specific activity (215.8 U nmol-1 versus 94.7 U nmol-1) and thermal stability (half-life of 48 h versus 5.5 h at 75°C) compared with those of XynA. However, GH10 XynB showed higher enzyme activity and thermostability than its truncated mutant without CBM. Site-directed mutagenesis of N-terminal amino acids resulted in a mutant, XynATM1-M, with 50% residual activity improvement at 75°C for 48 h, revealing that the disordered region influenced protein thermostability negatively. The thermal stability of both xylanases and their truncated mutants were consistent with their melting temperature (Tm), which was determined by using differential scanning calorimetry. Through homology modeling and cross-linking analysis, we demonstrated that for XynB, the resistance against thermoinactivation generally was enhanced through improving both domain properties and interdomain interactions, whereas for XynA, no interdomain interactions were observed. Optimized intramolecular interactions can accelerate thermostability, which provided microbes a powerful evolutionary strategy to assemble catalysts that are adapted to various ecological conditions. [ABSTRACT FROM AUTHOR]

A bisphosphoric acid-catalyzed 1,3-dipolar cycloaddition of buta-2,3-dienoates with azomethine ylides yields 3-methylenepyrrolidine derivatives with excellent enantioselectivity (up to 97% ee). [ABSTRACT FROM AUTHOR]

NYD-SP12 is a recently identified spermatogenesis-related gene with a pivotal role in human testis development. In this study, we analyzed between-species divergence and within-species variation of NYD-SP12 in seven representative primate species, four worldwide human populations, and 124 human clinical subjects. Our results indicate that NYD-SP12 evolves rapidly in both the human and the chimpanzee lineages, which is likely caused by Darwinian positive selection and/or sexual selection. We observed significant interpopulation divergence among human populations, which might be due to the varied demographic histories. In the association analysis, we demonstrated significant frequency discrepancy of a synonymous sequence polymorphism among the clinical groups with different sperm traits. [ABSTRACT FROM AUTHOR]

L-Proline amides derived from various chiral β-amino alcohols that bear substituents with various electron natures at their stereogenic centers are prepared and evaluated for catalyzing the direct Aldol reaction of 4-nitrobenzaldehyde with acetone. Catalysts with strong electron-withdrawing groups are found to exhibit higher catalytic activity and enantioselectivity than their analogues with electron-donating groups. The presence of 2 mol % catalyst 4g significantly catalyzes the direct Aldol reactions of a wide range of aldehydes with acetone and butanone, to give the β-hydroxy ketones with very high enantioselectivities ranging from 96% to >99% ee. High diastereoselectivity of 95/5 was observed for the anti Aldol product from the reaction of cyclohexanone, and excellent enantioselectivity of 93% ee was provided for anti Aldol product from the reaction of cyclopentanone. [ABSTRACT FROM AUTHOR]

The article presents a study which describes a novel protocol that directly converted 2-(2-propynyl)aniline derivatives into tetrahydroquinolines with high ee in one operation through consecutive hydroamination of alkynes/asymmetric transfer hydrogenation reactions. The generality of the protocol for 2-(2-propynyl)-aniline derivatives is investigated. An unprecedented protocol which directly transformed 2-(2-propylnyl)aniline derivatives into tetrahydroquinolines in one operation was developed.

Background: HBV-specific cytotoxic T lymphocyte (CTL) activity is believed to play a critical role in controlling HBV infection. The phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway manipulates cell fate decisions in many different cell types by regulating the activity of downstream effectors. We have previously testified that the fusion protein of CTP-HBcAg18-27--Tapasin could enter the cytoplasm of dendritic cells and efficiently induce robust specific CTL response in vitro. Objectives: In the present study, we evaluated specific CTL response and the level of apoptosis of CD8+ T cells induced by CTP-HBcAg18-27-Tapasin in HLA-A2 transgenic mice (H-2Kb). Meanwhile, we preliminary investigated PI3K, phosphorylation level of Akt, and mammalian target of rapamycin (mTOR) as positive regulator of the magnitude and effector function of the hepatitis B virus-specific cytotoxic T lymphocytes in HLA-A2 transgenic mice. Materials and Methods: HLA-A2 transgenic mice were immunized by intramuscular injection in the hind legs three times at one-week intervals with PBS, CTP-HBcAg18-27-Tapasin (50 μg), CTP-HBcAg18-27 (50 μg), HBcAg18-27-Tapasin (50 μg), and HBcAg18-27 (50 μg). One week after the last immunization, mice were sacrificed and splenocytes were harvested in strile condition. The specific CTL response was analyzed by flow cytometry and enzyme linked immunosorbent assay (ELISA); the expression of (PI3K)/Akt signaling was detected by RT-PCR and western blot. Results: The results showed that CTP-HBcAg18-27-Tapasin significantly increased the percentages of IFN-γ+ CD8α+ T cells, the numbers of these polyfunctional triple-cytokine-producing (IFN-γ, TNF-α, and IL-2) CD8+T cells, the secretion of cytokine IFN-γ, IL-2, and TNF-α, while in comparison to control group, it significantly decreased the percentage of apoptotic CD8+ T cells in HLA-A2 transgenic mice. Moreover, the expression of PI3K, P-Akt, and P-mTOR was significantly upregulated in CTP-HBcAg18-27-Tapasin group compared with control groups. Conclusions: In conclusion, CTP-HBcAg18-27-Tapasin could reduce apoptosis of CD8+ T cells, increase the percentages of IFN-γ+ CD8α+ T cells, and elicit cell-mediated immunity in HLA-A2 transgenic mice; these processes were associated with activation of the PI3K/Akt signaling pathway. [ABSTRACT FROM AUTHOR]

Background: Nine gene clusters dedicated to nonribosomal synthesis of secondary metabolites with possible antimicrobial action, including polymyxin and fusaricidin, were detected within the whole genome sequence of the plant growth-promoting rhizobacterium (PGPR) Paenibacillus polymyxa M-1. To survey the antimicrobial compounds expressed by M-1 we analyzed the active principle suppressing phytopathogenic Erwinia spp. Results: P. polymyxa M-1 suppressed the growth of phytopathogenic Erwinia amylovora Ea 273, and E. carotovora, the causative agents of fire blight and soft rot, respectively. By MALDI-TOF mass spectrometry and reversed-phase high-performance liquid chromatography (RP-HPLC), two antibacterial compounds bearing molecular masses of 1190.9 Da and 1176.9 Da were detected as being the two components of polymyxin P, polymyxin P1 and P2, respectively. The active principle acting against the two Erwinia strains was isolated from TLC plates and identified by postsource decay (PSD)-MALDI-TOF mass spectrometry as polymyxin P1 and polymyxin P2. These findings were corroborated by domain structure analysis of the polymyxin (pmx) gene cluster detected in the M-1 chromosome which revealed that corresponding to the chemical structure of polymyxin P, the gene cluster is encoding D-Phe in position 6 and L-Thr in position 7. Conclusions: Identical morphological changes in the cell wall of the bacterial phytopathogens treated with either crude polymyxin P or culture supernatant of M-1 corroborated that polymyxin P is the main component of the biocontrol effect exerted by strain M-1 against phytopathogenic Erwinia spp. [ABSTRACT FROM AUTHOR]

Background: Nearly 350 million persons worldwide are chronically infected with hepatitis B virus (HBV). Ubiquitin (Ub) is a highly conserved small regulatory protein, ubiquitous in eukaryotes, that usually serves as a signal for the target protein that is recognised and degraded in proteasomes . The Ub-mediated processing of antigens is rapid and efficient and stimulates cell-mediated immune responses. Accordingly, Ubmediated processing of antigens has been widely used in chronic-infection and cancer studies to improve immune response. Objectives: Many clinical trials have shown that DNA vaccine potency needs to be greatly enhanced. Here, we report a new strategy for designing an HBV DNA vaccine using the ubiquitin (Ub) sequence. The aim of this study was to investigate a novel DNA vaccination, based on the expression of HBV core antigen (HBcAg), fused to Ub to enhance DNA vaccine potency. Materials and Methods: Mouse ubiquitin fused to the HBcAg gene and cloned into the eukaryotic vector pcDNA3.1 (-). BALB/c mice were immunized with recombinant pUb- HBcAg or pHBcAg DNA vaccine. Lymphocyte proliferation assay, intracellular IFN-γ assay, CTL cytotoxicity assay, and antibody assay were performed to analyze the cellular and humoral immune responses to our DNA constructs. Results: HBcAg was expressed effectively in the COS-7 cells that were transiently transfected with pUb-HBcAg. Strong anti-HBc IgG responses were elicited in mice that were immunized with pUb-HBcAg. The endpoint titers of anti-HBc peaked at 1:656100 on the 42nd day after the third immunization. pUb-HBcAg stimulated greater lymphocyte proliferation and induced higher levels of IL-2 and IFN-γ and a greater percentage of HBcAg-specific CD8+ T cells in mice than pHBcAg. In the CTL assay, the specific lysis rate reached 56.5% at an effector:target ratio of 50:1 in mice that were immunized with pUb-HBcAg. Conclusions: pUb-HBcAg elicits specific anti-HBc responses and induces HBc-specific CTL responses in immunized BALB/c mice. Our results imply that Ub can be used as a molecular adjuvant that enhances the potency of DNA vaccines. [ABSTRACT FROM AUTHOR]

Three inorganic–organic compounds based on [MoxOy]n−chains, [Ag4(3-pttz)2Mo3O10] (1) (3-pttz = 5-(3-pyridyl) tetrazolate), [Ag4(2-pttz)2Mo4O13] (2) (2-pttz = 5-(2-pyridyl) tetrazolate), and [Ag4(pzttz)2Mo4O13] (3) (pzttz = 5-(pyrazinyl) tetrazolate), have been self-assembled, accompanied by in situformation processes of the 5-substituted tetrazolate ligands under hydrothermal condition. Compound 1features a 3D framework composed of [Mo3O10]2−chains cross-linked by [Ag4(3-pttz)2]2+belts. Compounds 2and 3reveal the 3D structures based on [Mo4O13]2−chains pillared by silver tetrazolate polymeric chains. The three title compounds represent the first three examples that the tetrazolate ligands are introduced into the backbones of the [MoxOy]n−anion chains. [ABSTRACT FROM AUTHOR]

In the presence of the heavy atom perturber Pb(Ac)2, fluorescein (HFin) can emit strong and stable room temperature phosphorescence (RTP) on the surface of a nitrocellulose membrane (NCM) at λex max/λem max = 480/648 nm. It can be spiked with the 1.5-generation polyamidoamine dendrimers (abbreviated: D-1.5) to emit stronger RTP. It was found that a quantitative specific affinity adsorption (AA) reaction between concanavalin agglutinin (abbreviated: Con A) labeled with D-1.5-HFin and N-acetylglucosamine (G) could be carried out on the surface of NCM. The product of the reaction (D-1.5-HFin- Con A-G) could emit strong and stable RTP, and the ΔIp was proportional to the content of G. According to the above facts, a new method for determination of G by affinity adsorption solid substrate-room temperature phosphorimetry (AA-SS-RTP) was established, based on Con A labeled with fluorescein using D-1.5 dendrimers molecules as sensitizer. The linear range of the sandwich method was 0.040–60 pg G spot−1 (corresponding concentration range: 0.10–150 ng mL−1; sample volume: 0.40 µL spot−1). The regression equation of the working curve was ΔIp = 6.880 + 5.610 mG pg spot−1, r = 0.9987. The working solutions containing 0.10 and 150 ng mL−1 G were determined repeatedly 11 times, respectively. The corresponding RSDs were 2.9 and 3.8%. The detection limit of this method calculated by 3Sb/k was 0.021 pg spot−1 (5.2 × 10−11 g mL−1). Compared with the direct method (detection limit: 0.078 pg spot−1, linear range: 0.40–40 pg G spot−1), the sensitivity was obviously improved and the linear range was wider. This method has been successfully applied to the determination of G in human plasma, as well as to the supervision and forecast of human diseases, for it is of good sensitivity, accuracy and precision. [ABSTRACT FROM AUTHOR]

Evaluates functional coupling between ‘R-type’ calcium[²+] channels and insulin secretion in the insulinoma cell line INS-1. Amplification of cDNA fragments; Use of peptide-specific antibodies for immunostaining; Effect of selective peptide antagonist on different splice variant.

The article describes the multi-dimensional metal-organic crystal structure of poly[diaqua(µ4-benzene-1,2-dicarboxylate)(isonicotinato-K2O,O')-gadolinium (Gd)III]. It shows the asymmetric unit of the compound consisting of GdIII) ion, benzenedicarboxylate, isonicotinate and aqua ligands. Also observed are the coordination of the GdIII with carboxylate oxygen atoms and terminal water molecules and the structure's adoption of a single bidentate chelating and a tretradentate bridging mode.