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A layer silicate-like zinc(II) benzimidazolate polymer {[Zn2(Bim)3(OH)(H2O)]·(DMF)(H2O)3}∞ (1) was synthesized at room temperature and characterized with X-ray single-crystallography: Monoclinic, space group C2/m (No.12), a = 10.423(3) A, b = 17.416(6) A, c = 16.583(5) A, β = 92.698(4), V = 3006.8(17) A3.

Spatiotemporal control of singlet oxygen ((1)O2) release is a major challenge for photodynamic therapy (PDT) against cancer with high therapeutic efficacy and minimum side effects. Here a selenium-rubyrin (NMe2Se4N2)-loaded nanoparticle functionalized with folate (FA) was designed and synthesized as an acidic pH-activatable targeted photosensitizer. The nanoparticles could specifically recognize cancer cells via the FA-FA receptor binding and were selectively taken up by cancer cells via receptor-mediated endocytosis to enter lysosomes, in which NMe2Se4N2 was activated to produce (1)O2. The pH-controllable release of (1)O2 specially damaged the lysosomes and thus killed cancer cells in a lysosome-associated pathway. The introduction of selenium into the rubyrin core enhanced the (1)O2 generation efficiency due to the heavy atom effect, and the substitution of dimethylaminophenyl moiety at meso-position led to the pH-controllable activation of NMe2Se4N2. Under near-infrared (NIR) irradiation, NMe2Se4N2 possessed high singlet oxygen quantum yield (ΦΔ) at an acidic pH (ΦΔ = 0.69 at pH 5.0 at 635 nm) and could be deactivated at physiological pH (ΦΔ = 0.06 at pH 7.4 at 635 nm). The subcellular location-confined pH-activatable photosensitization at NIR region and the cancer cell-targeting feature led to excellent capability to selectively kill cancer cells and prevent the damage to normal cells, which greatly lowered the side effects. Through intravenous injection of FA-NMe2Se4N2 nanoparticles in tumor-bearing mice, tumor elimination was observed after NIR irradiation. This work presents a new paradigm for specific PDT against cancer and provides a new avenue for preparation of highly efficient photosensitizers.

A binuclear Zn(II) complex: Na[Zn2(pbdiim)Cl5] · 1.5H2O (pbdiim = 2-(2-pyridyl)benzo[1,2-d;4,5-d′]diimidazole) (1) has been prepared and the crystal structure determined by single-crystal X-ray diffraction. The pbdiim ligand coordinates to two zinc ions in which each zinc ion adopts a distorted tetrahedral geometry. Complex 1 has a more planar structure and displays strong blue fluorescence at room temperature than the pbdiim molecule.

A 2D grid-shaped bimetallic imidazolate polymer [CoIICuI2(Im)4];∞ (1) was solvothermally synthesized and characterized with single crystal X-ray analysis: tetragonal space group P21/c (No.114), a = b = 10.9513(15) A, c = 6.3063(13) A, V = 756.3(2) A3. This is the first cobalt(II) imidazolate polymer hybridized with other transition metals.

Flightin was initially identified in Drosophila melanogaster. Previous work has shown that Drosophila flightin plays a key role in indirect flight muscle (IFM) function and has limited expression in the IFM. In this study, we demonstrated that flightin is conserved across the Pancrustacea species, including winged insects, non-winged insects, non-insect hexapods and several crustaceans. The brown planthopper (BPH), Nilaparvata lugens (Stal) (Hemiptera: Delphacidae), a long-distance migration insect with wing dimorphism, is the most destructive rice pest in Asia. We showed that flightin was one of the most differentially expressed genes in macropterous and brachypterous BPH adults. In female BPHs, flightin was expressed in the IFM of macropterous adults, no expression was detected in brachypterous ones; while in male BPHs, flightin was not only expressed in the IFM of macropterous adults, but also in the dorsal longitudinal muscle (DLM) in the basal two abdominal segments of both macropterous and brachypterous ones. RNAi and transmission electron microscopy results showed that flightin played key roles in maintaining IFM and male DLM structure, which drive wing movements in macropterous adults and the vibration of the male-specific tymbal, respectively. Using Daphnia magna as an example of a crustacean species, we observed that flightin was expressed in juvenile instars and adults, and was localized in the antenna muscles. These results illustrate the functional variations of flightin in insects and other arthropod species and provide clues as to how insects with flight apparatuses evolved from ancient pancrustaceans.

ZnO-nanofilm/Si-micropillar p-n nanoheterostructure arrays were prepared by growing n-type ZnO onto a p-type nanoporous Si pillar array. Its current-voltage characteristics of nanoheterostructure showed good rectifying behavior with onset voltage of ~1.5 V, forward current density of ~28.7 mA/cm(2) at 2.5 V, leakage current density of ~0.15 mA/cm(2) and rectifying ratio of ~121 at ± 2.5 V. The electron transport across nanohetreostructure obeys the trap-charge-limit current model. Moreover, strong white light electroluminescence from ZnO-nanofilm/Si-micropillar light-emitting diode (LED) has been achieved, which could open up possibilities to build new ZnO/Si-based highly efficient solid-state lighting devices.

Two novel coordination polymers [Mn3(EPDA)2(H2O)8·(ENA)·(ClO4)·0.5(HClO4)·(CH3OH)·2(H2O)]n (1) and[Zn(EPDA)(H2O)]n (2) (EPDA = 5-ethylpyridine-2, 3-dicarboxylic acid, ENA = 5-ethylnicotinate acid) were synthesized and characterized by IR and UV/Vis spectroscopy, elemental analysis, PXRD, TGA, photoluminescence, and single-crystal X-ray diffraction. Organic EPDA2– and ENA– anions, the decomposition products of ENA-Pmmi by removing the –Pmmi group under in situ solvothermal conditions, were obtained by performing the reactions of ENA-Pmmi with MnII or ZnII perchlorate. In complex 1, the MnII ions were bridged by μ4-EPDA2– anions to give a 2D positively charged layer, and the free ENA– anion and solvent molecules are filled into the gap between the layers through hydrogen bonding interactions to form a sandwich structure. In compound 2, the μ3-EPDA2– anions bridge divalent Zn2+ ions to form a 1D chain, and the ENA– anions are not involved in stacking interactions but left in the residual solution. In addition, the ENA-Imoi instead of ENA-Pmmi, was selected to further investigate this reaction (ENA-Pmmi and ENA-Imoi are imazethapyr homologues), and the same experimental results could be obtained.

Template-assembled synthetic G-quartet (TASQ) has been reported recently as a G-quadruplex ligand interacting with DNA according to an unprecedented, nature-inspired ‘like likes like’ approach, based on the association between two G-quartets, one being native (quadruplex) and the other one artificial (ligand). Herein, a novel TASQ-based ligand is designed, synthesized and its quadruplex-recognition properties are evaluated in vitro: PorphySQ (for porphyrin-templated synthetic G-quartet) displays enhanced quadruplex recognition properties as compared to the very first reported prototype (DOTASQ, for DOTA-templated synthetic G-quartet), since the porphyrin template insures a more stable intramolecular G-quartet fold due to self-stabilizing interactions that may take place intramolecularly between the porphyrin ring and the formed G-quartet.

Oxygen reduction catalyzed by cofacial metalloporphyrins at the 1,2-dichlorobenzene−water interface was studied with two lipophilic electron donors of similar driving force, 1,1'-dimethylferrocene (DMFc) and tetrathiafulvalene (TTF). The reaction produces mainly water and some hydrogen peroxide, but the mediator has a significant effect on the selectivity, as DMFc and the porphyrins themselves catalyze the decomposition and the further reduction of hydrogen peroxide. Density functional theory calculations indicate that the biscobaltporphyr- in, 4,5-bis(5-(2,8,13,17-tetraethyl-3,7,12,18-tetramethylporphyrinyl))-9,9-dimethylxanthene, Co2(DPX), actually catalyzes oxygen reduction to hydrogen peroxide when oxygen is bound on the "exo" side ("dock-on") of the catalyst, while four-electron reduction takes place with oxygen bound on the "endo" side ("dock-in") of the molecule. These results can be explained by a "dock-on/dock-in" mechanism. The next step for improving bioinspired oxygen reduction catalysts would be blocking the "dock- on" path to achieve selective four-electron reduction of molecular oxygen.

DSC1 and BSC1 are two founding members of a novel family of invertebrate voltage-gated cation channels with close structural and evolutionary relationships to voltage-gated sodium and calcium channels. In this study, we searched the published genome sequences for DSC1 orthologs. DSC1 orthologs were found in all 48 insect species, and in other invertebrate species belonging to phyla Mollusca, Cnidaria, Hemichordata and Echinodermata. However, DSC1 orthologs were not found in four arachnid species, Ixodes scapularis, Rhipicephalus microplus, Tetranychus urticae and Varroa destructor, two species in Annelida or any vertebrate species. We then cloned and sequenced NlSC1 and BmSC1 full-length cDNAs from the brown planthopper (Nilaparvata lugens) and the silkworm (Bombyx mori), respectively. NlSC1 and BmSC1 share about 50% identity with DSC1, and the expression of NlSC1 and BmSC1 transcripts was most abundant in the head and antenna in adults. All DSC1 orthologs contain a unique and conserved DEEA motif, instead of the EEEE or EEDD motif in classical calcium channels or the DEKA motif in sodium channels. Phylogenetic analyses revealed that DSC1 and its orthologs form a separate group distinct from the classical voltage-gated sodium and calcium channels and constitute a unique family of cation channels. The DSC1/BSC1-family channels could be potential targets of new and safe insecticides for pest control.

Cyclic dimeric GMP (c-di-GMP) is a bacterial second messenger that modulates many biological processes. Although its role in bacterial pathogenesis during mammalian infection has been documented, the role of c-di-GMP in a pathogen's life cycle within a vector host is less understood. The enzootic cycle of the Lyme disease pathogen Borrelia burgdorferi involves both a mammalian host and an Ixodes tick vector. The B. burgdorferi genome encodes a single copy of the diguanylate cyclase gene (rrp1), which is responsible for c-di-GMP synthesis. To determine the role of c-di-GMP in the life cycle of B. burgdorferi, an Rrp1-deficient B. burgdorferi strain was generated. The rrp1 mutant remains infectious in the mammalian host but cannot survive in the tick vector. Microarray analyses revealed that expression of a four-gene operon involved in glycerol transport and metabolism, bb0240-bb0243, was significantly downregulated by abrogation of Rrp1. In vitro, the rrp1 mutant is impaired in growth in the media containing glycerol as the carbon source (BSK-glycerol). To determine the contribution of the glycerol metabolic pathway to the rrp1 mutant phenotype, a glp mutant, in which the entire bb0240-bb0243 operon is not expressed, was generated. Similar to the rrp1 mutant, the glp mutant has a growth defect in BSK-glycerol medium. In vivo, the glp mutant is also infectious in mice but has reduced survival in ticks. Constitutive expression of the bb0240-bb0243 operon in the rrp1 mutant fully rescues the growth defect in BSK-glycerol medium and partially restores survival of the rrp1 mutant in ticks. Thus, c-di-GMP appears to govern a catabolic switch in B. burgdorferi and plays a vital role in the tick part of the spirochetal enzootic cycle. This work provides the first evidence that c-di-GMP is essential for a pathogen's survival in its vector host., Author Summary The Lyme disease pathogen Borrelia burgdorferi has two sets of two-component systems, Hk1-Rrp1 and Hk2-Rrp2. The Hk2-Rrp2 signaling system has been shown to modulate differential expression of numerous surface lipoprotein genes and to play an essential role in spirochete transformation from a tick colonizer to a mammalian host-adapted state. In this study, we show that Rrp1, the only diguanylate cyclase in B. burgdorferi, is not required for mammalian infection but is essential for spirochete survival in the tick vector. We identify over 39 genes whose expression is influenced by this c-di-GMP signaling system. We further demonstrate that one set of the Rrp1-dependent genes, the glp operon for glycerol transport and metabolism, plays an important role in the spirochete adaptation to tick environment and partially accounts for the essentiality of c-di-GMP for B. burgdorferi survival in ticks.

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The seventh author's name was spelled incorrectly. The correct name is: Frank Gherardini. The affiliation for the third author was incorrect. Tao Lin is not affiliated with #4 but with #5 Department of Pathology and Laboratory Medicine, University of Texas Medical School at Houston, Houston, Texas, United States of America.

Background The brown planthopper (BPH) Nilaparvata lugens (Stal) is one of the most serious insect pests of rice in Asia. However, little is known about the mechanisms responsible for the development, wing dimorphism and sex difference in this species. Genomic information for BPH is currently unavailable, and, therefore, transcriptome and expression profiling data for this species are needed as an important resource to better understand the biological mechanisms of BPH. Methodology/Principal Findings In this study, we performed de novo transcriptome assembly and gene expression analysis using short-read sequencing technology (Illumina) combined with a tag-based digital gene expression (DGE) system. The transcriptome analysis assembles the gene information for different developmental stages, sexes and wing forms of BPH. In addition, we constructed six DGE libraries: eggs, second instar nymphs, fifth instar nymphs, brachypterous female adults, macropterous female adults and macropterous male adults. Illumina sequencing revealed 85,526 unigenes, including 13,102 clusters and 72,424 singletons. Transcriptome sequences larger than 350 bp were subjected to Gene Orthology (GO) and KEGG Orthology (KO) annotations. To analyze the DGE profiling, we mainly compared the gene expression variations between eggs and second instar nymphs; second and fifth instar nymphs; fifth instar nymphs and three types of adults; brachypterous and macropterous female adults as well as macropterous female and male adults. Thousands of genes showed significantly different expression levels based on the various comparisons. And we randomly selected some genes to confirm their altered expression levels by quantitative real-time PCR (qRT-PCR). Conclusions/Significance The obtained BPH transcriptome and DGE profiling data provide comprehensive gene expression information at the transcriptional level that could facilitate our understanding of the molecular mechanisms from various physiological aspects including development, wing dimorphism and sex difference in BPH.

The successful synthesis of tetraphenyltetraphenanthroporphyrin (TPTPhenP; 5a) in 2006 under modified Rothemund-Lindsey conditions yielded a tetraphenyl porphyrinoid with a B band redshifted to an unprecedented 576 nm. Radially symmetric fused-ring expansion of tetraphenylporphyrin with phenanthrene moieties results in very deep saddling due to steric crowding and very marked redshifts of the Q and B (or Soret) porphyrinoid absorption bands. The extent to which the TPTPhenP structure can be further modified is explored, and the optical properties of TPTPhenPs are analyzed based on a perimeter model approach that makes use of time-dependent DFT calculations and magnetic circular dichroism spectroscopy and also based on a detailed analysis of the fluorescence emission. Attempts to introduce substituents at the ortho and meta positions of the meso-phenyl groups and to insert a central metal proved unsuccessful. The synthesis of a series of TPTPhenPs with strong electron-withdrawing (-CN, -NO(2)) and -donating (-CH(3), -N(CH(3))(2)) substituents at the para positions of the meso-phenyl rings is reported. Marked redshifts of the main spectral bands were consistently observed. The most pronounced spectral changes were observed with -N(CH(3))(2) groups (5i) due to a marked destabilization of the HOMO, which has large MO coefficients on the meso-carbon atoms. Protonation of 5i at both the ligand core and at the -N(CH(3))(2) groups resulted in unprecedented Q(00) band absorption at wavelengths greater than 1200 nm.

Using the magnetron sputtering technology, high quality Al2O3-based textured ZnO thin films (Al2O3/ZnO) which can be applied to solar cells' light trapping effect were fabricated by controlling the preparation parameters properly. X-ray diffraction (XRD) and Scanning electron microscopy (SEM) results show that O2 /(Ar+O2) flow ratio has great influence on Al2O3/ZnO films surface morphology during Al2O3 layer growth, the Al2O3/ZnO films with pyramid structure morphology were easily prepared as O2 /(Ar+O2) flow ratio is in the range of 16.7%~50%. According to the measurement results of Al2O3/ZnO films' resistivity and UV-Visible transmission spectra, the lowest resistivity of 0.0048Ωcm and optical transmission of larger than 80% were obtained for these Al2O3/ZnO films in this paper. After treated up to 720h under harsh environmental condition with relative humidity of 85°C and temperature of 80°C, these samples conductivity degradation is in the range of 12%~14% for Al2O3/ZnO films, which indicates that the Al2O3/ZnO films have better stability compared to ZnO films.

Borrelia burgdorferi , the Lyme disease pathogen, dramatically alters its protein profile when it is transmitted between ticks and mammals. Several differentially expressed proteins have been shown to be critical for the enzootic cycle of B. burgdorferi . In this study, we demonstrated that expression of the surface lipoprotein-encoding gene bba07 is induced by an elevated temperature and a reduced pH during in vitro cultivation, as well as during nymphal tick feeding. Expression of bba07 is regulated by the Rrp2-RpoN-RpoS pathway, a central regulatory network that is activated during nymphal feeding. By generating a bba07 mutant of an infectious strain of B. burgdorferi , we demonstrated that although BBA07-deficient spirochetes were capable of infecting mice via needle inoculation and surviving in ticks, they were defective in infection of mammals via tick transmission. Complementation of the bba07 mutant with a wild-type copy of bba07 partially restored the transmission defect of the bba07 mutant. Based on these findings, we concluded that the surface lipoprotein BBA07 is produced during tick feeding and facilitates optimal transmission of B. burgdorferi from the tick vector to a mammalian host.

Borrelia burgdorferi, the Lyme disease spirochete, dramatically alters its transcriptome and proteome as it cycles between the arthropod vector and mammalian host. During this enzootic cycle, a novel regulatory network, the Rrp2-RpoN-RpoS pathway (also known as the σ54–σS sigma factor cascade), plays a central role in modulating the differential expression of more than 10% of all B. burgdorferi genes, including the major virulence genes ospA and ospC. However, the mechanism(s) by which the upstream activator and response regulator Rrp2 is activated remains unclear. Here, we show that none of the histidine kinases present in the B. burgdorferi genome are required for the activation of Rrp2. Instead, we present biochemical and genetic evidence that supports the hypothesis that activation of the Rrp2-RpoN-RpoS pathway occurs via the small, high-energy, phosphoryl-donor acetyl phosphate (acetyl∼P), the intermediate of the Ack-Pta (acetate kinase-phosphate acetyltransferase) pathway that converts acetate to acetyl-CoA. Supplementation of the growth medium with acetate induced activation of the Rrp2-RpoN-RpoS pathway in a dose-dependent manner. Conversely, the overexpression of Pta virtually abolished acetate-induced activation of this pathway, suggesting that acetate works through acetyl∼P. Overexpression of Pta also greatly inhibited temperature and cell density-induced activation of RpoS and OspC, suggesting that these environmental cues affect the Rrp2-RpoN-RpoS pathway by influencing acetyl∼P. Finally, overexpression of Pta partially reduced infectivity of B. burgdorferi in mice. Taken together, these findings suggest that acetyl∼P is one of the key activating molecule for the activation of the Rrp2-RpoN-RpoS pathway and support the emerging concept that acetyl∼P can serve as a global signal in bacterial pathogenesis., Author Summary Borrelia burgdorferi, the causative agent of Lyme disease, is maintained in nature in a complex enzootic cycle involving Ixodes ticks and mammals. A novel regulatory network, the Rrp2-RpoN-RpoS pathway, which governs differential expression of numerous genes of B. burgdorferi, is essential for this complex life cycle. In this study, we provide evidence showing that the activation of the Rrp2-RpoN-RpoS pathway is modulated, not by the predicted histidine kinase for Rrp2, but rather by acetyl phosphate (acetyl∼P), the intermediate of the Ack-Pta (acetate kinase-phosphate acetyltransferase) metabolic pathway. Based on our findings, we propose that during the enzootic cycle of B. burgdorferi, changes in environmental cues and nutrient conditions lead to an increase in the intracellular acetyl∼P pool in B. burgdorferi, which in turn modulates the activation of the Rrp2-RpoN-RpoS pathway.

In the title compound, C9H14N+·Br−, an intramolecular N—H...Br interaction links the anion to the cation. In the crystal structure, intermolecular N—H...Br interactions link the molecules into a three-dimensional network.

I appreciate the mechanism underlying the role of lactate in lipid metabolism proposed by Liu et al. (1). They found that lactate suppresses lipolysis in adipose tissue through a direct activation of GPR81. However, the argument that lactate suppresses lipolysis might be worthy of further consideration. Several studies have shown that there exists a substrate cycle or futile cycle in skeletal muscle as well as in adipose tissue, which dissipates redundant energy as heat via the cycle of synthesis, hydrolysis, and oxidation of triglyceride (2, 3). Furthermore, Hagstrom-Toft et al. (4) found that hypoglycemia increases both lipid and lactate mobilization in skeletal muscle and adipose tissues. It is well known that hypoglycemia will promote lipid hydrolysis to release fatty acids for providing energy by oxidation. I also found that lactate concentration was positively correlated with glycerol concentration in skeletal muscle and adipose tissues (unpublished data). Therefore, it is possible that lactate produced by anaerobic glycolysis might relieve the inhibition of glucose aerobic oxidation on fatty acid oxidation or adjust intracellular redox state via lactate shuttle in skeletal muscle and adipose tissues and thus promote fatty acid oxidation.

The asymmetric unit of the title compound, C8H6N8·2H2O, contains one half-molecule, with the benzene ring on a centre of symmetry, and two uncoordinated water molecules. The benzene ring is oriented at a dihedral angle of 34.43 (12)° with respect to the tetrazole ring. Strong O—H...N hydrogen bonds link the water molecules to the N atoms of the tetrazole ring. In the crystal structure, strong intermolecular O—H...O and O—H...N hydrogen bonds link the molecules into a network. One of the water H atoms is disordered over two positions and was refined with occupancies of 0.50.

In the title compound, (C12H11N3)[SbCl5]·H2O, the SbIIIcentre is surrounded by five Cl atoms and displays a distorted square-pyramidal coordination geometry. The dihedral angle formed by the plane of the imidazole ring system with the pyridine ring is 4.380 (15)°. The crystal structure is stabilized by N—H...Cl, O—H...Cl and N—H...O hydrogen bonds, forming a three-dimensional network.

The molecule of the title Schiff base, C16H15N3, is non-planar and displays a trans configuration with respect to the C=N double bond. The two benzene rings make a dihedral angle of 49.24 (3)°.

Rrp2 is the sole σ 54 -dependent transcriptional activator present in the Borrelia burgdorferi genome. We showed that recombinant Rrp2 binds to DNA in a sequence-nonspecific manner. During infection, Rrp2 activates σ 54 -dependent rpoS expression without an apparent upstream enhancer element commonly associated with other σ 54 -dependent transcriptional activators.

To investigate the method and the outcome of the acetabular reconstruction in the Crowe III dysplastic hip.From January 2001 to June 2007, 43 cases (54 hips) were diagnosed osteoarthritis secondary to Crowe III dysplastic hip. Total hip arthroplasty was performed in all cases. The Harris score was 39 pre-operation. The method of the acetabular reconstruction included acetabular deepening (group A), medial-wall osteotomy (group B), femoral head bone grafting (group C). Radiography data and Harris score were taken to evaluate the clinical outcome.The method of the acetabular reconstruction included acetabular deepening in 27 cases (34 hips), medial-wall osteotomy in 12 cases (15 hips), femoral head bone grafting in 4 cases (5 hips). Forty cases were followed up by the mean time of 29 months. The bone union time of the osteotomy and bone grafting were 4 - 5 months postoperation. In the three groups the obliquity angle of the cup were (41.0 +/- 7.5) degrees , (46.0 +/- 7.7) degrees , (39.0 +/- 11.0) degrees ; the anteversion angle of the cup were (10.0 +/- 2.8) degrees , (9.0 +/- 2.5) degrees , (4.0 +/- 1.9) degrees ; the rotation center of the hip was shift superiorly (8.4 +/- 3.6) mm, (7.3 +/- 2.6) mm, (1.2 +/- 0.5) mm; the rotation center of the hip were shift internally (7.0 +/- 1.5) mm, (9.9 +/- 1.7) mm, (-2.7 +/- 1.2) mm, and the Harris score were 89, 91, 86 at the follow up. The complication included deep venous thrombosis in 2 cases, pulmonary embolism in 2 cases, sciatic nerve palsy in 4 cases.Acetabular deepening, medial-wall osteotomy, femoral head bone grafting can be used in reconstruction of the acetabular in the Crowe III dysplastic hip.

The availability of microbial genome information has provided a fruitful opportunity for studying regulatory networks in a variety of pathogenic bacteria. In an initial effort to elucidate regulatory networks potentially involved in differential gene expression by the Lyme disease pathogen Borrelia burgdorferi , we have been investigating the functions and regulation of putative transcriptional regulatory factors predicted to be encoded within the B. burgdorferi genome. Herein we report the regulation of one of the predicted transcriptional regulators, LtpA (BB0355), which is homologous to the transcriptional regulator CarD from Myxococcus xanthus . LtpA expression was assessed in response to various environmental stimuli. Immunoblot and quantitative reverse transcription-PCR analyses revealed that unlike many well-characterized differentially regulated Borrelia genes whose expression is induced by elevated temperature, the expression of LtpA was significantly downregulated when spirochetes were grown at an elevated temperature (37°C), as well as when the bacteria were cultivated in a mammalian host-adapted environment. In contrast, LtpA was induced at a lower culture temperature (23°C). Further analyses indicated that the downregulation of LtpA was not dependent on the Rrp2-RpoN-RpoS regulatory pathway, which is involved in the downregulation of OspA when B. burgdorferi is grown in a mammalian host-adapted environment. LtpA protein levels in B. burgdorferi were unaltered in response to changes in the pH in the borrelial cultures. Multiple attempts to generate an LtpA-deficient mutant were unsuccessful, which has hampered the elucidation of its role in pathogenesis. Given that LtpA is exclusively expressed during borrelial cultivation at a lower temperature, a parameter that has been widely used as a surrogate condition to mimic B. burgdorferi in unfed (flat) ticks, and because LtpA is homologous to a known transcriptional regulator, we postulate that LtpA functions as a regulator modulating the expression of genes important to B. burgdorferi 's survival within its arthropod vector.

In the title compound, C13H15BF2N2, the two pyrrole rings are almost coplanar, with a dihedral angle of 3.08 (10)°. The BF2 plane is almost perpendicular to the boron–dipyrromethene ring plane, with a dihedral angle of 89.99 (7)°.

Bombyx mori nucleopolyhedrovirus (BmNPV) ORF118 (bm118) is homologous to Autographa californica nucleopolyhedrovirus (AcMNPV) ORF142, one of the core genes existing in all baculovirus genomes sequenced to date, suggesting that Bm118 plays a critical role in viral infection. In this study, the primary role of Bm118 was investigated by using homologous recombination in Escherichia coli to generate a bm118 knockout bacmid containing the BmNPV genome. In addition, the bm118 rescue bacmid was constructed by transposing a bm118 gene cassette into the polh locus of the bm118 knockout bacmid. Transfection assays demonstrated that the bm118 knockout bacmid was incapable of producing budded virion (BV). Nevertheless, this defect could be partially recovered by a rescue bacmid. Electron microscopy analysis revealed that the bm118 knockout produced aberrant capsids characterized by translucent, elongated nucleocapsids present as bundles within the nuclei. This construct also produced polyhedra lacking virions. These results reveal that Bm118 is essential for BV production and nucelocapsid maturation.

In the title compound, [Mn(C(8)H(2)NO(6))(H(2)O)(2)](n), each pyridine-2,4,6-tricarboxyl-ate (tpc) ligand bridges two Mn(II) ions with the formation of polymeric chains located on a twofold rotation axis. Each Mn(II) ion is coordinated by two O and one N atoms from one tpc ligand, two O atoms from another ligand and two water mol-ecules in a distorted penta-gonal-bipyramidal geometry. The Mn-N [2.243 (2) Å] and Mn-O [2.206 (2)-2.3123 (16) Å] bond lengths are normal. The coordinated water mol-ecules link neighbouring polymeric chains via O-H⋯O hydrogen bonds into a two-dimensional framework parallel to the bc plane.

The tea looper caterpillar, Ectropis obliqua, is one of the major pests of tea bushes. E. obliqua single-nucleocapsid nucleopolyhedrovirus (EcobSNPV) has been used as a commercial pesticide for biocontrol of this insect. However only limited genetic analysis for this important virus has been done up to now. EcobSNPV was characterized in this study. Electron microscopy analysis of the occlusion body showed polyhedra of 0.7 to 1.7 mum in diameter containing a single nucleocapsid per envelope of the virion. A 15.5 kb genomic fragment containing EcoRI-L, EcoRI-N and HindIII-F fragments, was sequenced. Analysis of the sequence revealed that the fragment contained eleven potential open reading frames (ORFs): lef-1, egt, 38.7k, rr1, polyhedrin, orf1629, pk-1, hoar and homologues to Spodoptera exigua multicapsid NPV (SeMNPV) ORFs 15, 28, and 29. Gene arrangement and phylogeny analysis suggest that EcobSNPV is closely related to the previously described Group II NPV. Bioassays on lethal concentration (LC(50) and LC(90)) and lethal time (LT(50) and LT(90)) were conducted to test the susceptibility of E. obliqua larvae to the virus.

Homologues of Helicoverpa armigera nucleopolyhedrovirus (HearSNPV) orf33 are found in all 22 completely sequenced members of the lepidopteran nucleopolyhedroviruses and granuloviruses, but so far their functions are unknown. In this report, we describe the characterization of HearSNPV orf33 (ha33). Northern blot analysis showed a single transcript of ha33 of approximately 0.7 kb was transcribed beginning at 3 h post-infection in infected Helicoverpa zea cells (HzAM1) and the gene product could be detected as early as 6 h post-infection by western blot analysis using a rabbit derived polyclonal antibody, suggesting it was an early gene. Western blot analysis also demonstrated the ha33 protein in infected cells was a 31 kDa protein, larger than the theoretical size of 28.4 kDa, and located in the envelope fraction of budded virions (BVs). The results suggested that HearSNPV ha33 gene is a functional gene that encodes a novel structural protein of baculovirus BVs, BV-e31.

A cDNA encoding melittin in Apis cerana cerana was obtained by PCR from the recombinant plasmid and cloned into the GST fusion expression vector pGEX-4T-2 for expression of the protein. The expressed protein of about 29 kDa was detected by Western blot and triple antibody sandwich ELISA, indicating that the recombinant protein is the fusion protein of GST-AccM. The expression conditions of GST-AccM fusion protein for Escherichia coli BL21 transformant were optimized. Thin layer scanning on the SDS-PAGE profiles of GST-AccM showed that the expressed protein accumulated up to about 15.2% of total protein of bacterial cells under the optimized expression condition. Purified and recovered recombinant melittin of A. cerana cerana showed bioactivity in activating rabbit platelets to aggregate.

Nanoporous gold film (NPGF) composed of gold nanoparticles was used to cover a large Si nanowire array (SiNWA) by simple metal-assisted chemical etching and metal reduction processes. Three-dimensional SiNWA/NPGF was employed as an active substrate for surface-enhanced Raman scattering (SERS). The results show that the detection limit for crystal violet was as low as 10−12M, and the Raman enhancement factor was as large as 107 with a relative standard deviation of less than 20%. After calibrating the Raman peak intensities of crystal violet and thiram could be quantitatively detected. More importantly, the SERS substrates are recyclable and can be used for many gold surface adsorbates such as p-aminothiophenol, crystal violet, Rhodamine 6G, and methyl orange, which can all be rapidly and completely removed from the NPGF surface. Our findings are an important advance in SERS substrates and will allow the quantitative and recyclable detection of trace organic contaminants.

Dendritic silver nanostructures coated with silica nanofilm are synthesized via hydrothermal etching using silver nitrate, hydrofluoric acid, and hydrogen peroxide and controlling the reagent concentration, reaction time, and temperature. The silver dendritic nanostructures are employed as substrates for surface-enhanced Raman scattering (SERS) and exhibit high sensitivity and excellent stability. Calibration of the Raman peak intensities of rhodamine 6G and thiram allowed quantitative detection of these organic molecules. Our findings are a significant advance in developing robust SERS substrates for fast detection of trace organic contaminants.

In the title compound, C13H9N5, the dihedral angle between the pyridyl and benzodi­imidazole rings is 17.76 (7)°. The mol­ecules form a two-dimensional layer structure via N—H⋯N and C—H⋯N intermolecular hydrogen bonds. The layers lie parallel to the ab plane and are stacked along the c axis.

Large scale and highly ordered flowerlike ZnO/Si nanostructures are successfully prepared by combining two common techniques, viz. hydrothermally etch fabrication of nanoporous Si pillar array (NSPA) and self-catalytic chemical vapor transport growth of ZnO nanowires. Au nanoparticles are decorated onto the ZnO/Si nanoflowers by the hydrothermal method. The formed Au/ZnO/NSPA array is evaluated as a surface-enhanced Raman scattering SERS-active substrate, which exhibits very high sensitivity and good stability and reproducibility. The excellent SERS enhancement is mainly attributed to the strong local electromagnetic effect which is associated with the unique flowerlike nanostructures of Au/ZnO/NSPA and the formed metal-induced gap states at the Au/ZnO interfaces. The results indicated that Au/ZnO/NSPA might be employed as a promising SERS substrate for the fast detection of low-concentration biomolecules.

A large scale heterostructure array of ZnO nanowires/silicon nanoporous pillar array (Si-NPA) was prepared by a self-catalytic thermal evaporation and vapor-phase transport method, and an ultrahigh field emission current density of 1.55 mA cm−2 was obtained under an operating electric field of 4.0 V μm−1, with a low turn-on field of 1.65 V μm−1. The enhancement factor calculated according to the Fowler–Nordheim theory was ∼3141. The excellent field emission performance was attributed to the unique structure of ZnO/Si-NPA, especially the formation of ZnO nanowires on regular Si pillar array. Our work indicated that ZnO/Si-NPA might be an ideal candidate cathode of potential applications in flat panel displays and high brightness electron sources.

A silicon nanoporous pillar array (Si-NPA) is a silicon hierarchical structure with regularly patterned surface morphology. Through a heterogeneous reaction process, the nanocrystallites of zinc sulfide (nc-ZnS) were grown onto the Si-NPA and a uniquely patterned core/shell nanoheterostructure array (ZnS/Si-NPA) was obtained. The pillars of the ZnS/Si-NPA were constructed by an outermost shell of a nc-ZnS membrane, an innermost core of a nanoporous silicon pillar and an interface with nc-ZnS embedded into an amorphous SiO2 matrix. The photoluminescence (PL) spectrum of the ZnS/Si-NPA showed that in addition to the two blue PL bands peaked at ~412 and ~491 nm observed in the Si-NPA, a green PL band at ~537 nm was observed in the ZnS/Si-NPA when it was excited by 300 nm ultraviolet light. Based on these experimental results, the two blue PL bands of the ZnS/Si-NPA came from a Si-NPA substrate, while the green PL band was attributed to the emission from the surface states of sulfur vacancies of nc-ZnS. The broad PL from blue to red in the visible region realized in the ZnS/Si-NPA might be applied in solid-state lighting devices with white light emission.

In the title compound, C9H12NO2+·Cl2PO2−, the molecular skeleton of the cation is nearly planar with an r.m.s. deviation of 0.0336 Å. In the crystal structure, intermolecular O—H...O hydrogen bonds link cations and anions into chains running along [1overline{1}0].

In the title mononuclear copper(II) complex, [Cu(C14H9N2O)2], the CuII atom, situated on an inversion centre, shows a slightly distorted square-planar geometry and is coordinated by the N and O atoms from two deprotonated symmetry-related Schiff base ligands. The Cu—N and Cu—O bond lengths are 2.009 (2) and 1.888 (2) Å, respectively. The dihedral angle between the cyanophenyl rings and phenolate rings is 42.28 (13)°.

A CdS/Si nanoheterostructure was prepared by growing CdS nanocrystallites onto silicon nanoporous pillar array. A rectification effect with an onset voltage of ∼1 V, a forward current density of ∼170 mA cm−2 at 4.5 V, a leakage current density of ∼8×10−2 mA cm−2, and a reverse breakdown voltage of ∼8 V was observed. The rectifying ratio was evaluated to be ∼215 at ±4.5 V. The electron transport across the nanoheterostructure was found to be mainly controlled by sulfur vacancies and obey the trap-limited model. These results indicate that CdS/Si nanoporous pillar array might be a promising material in fabricating photoelectronic nanodevices.

The asymmetric unit of the title molecule, C9H10N2O, contains two molecules. The fused benzene and imidazole rings are nearly coplanar, the largest deviations from the mean plane being 0.025 (3) Å at the non-bridgehead imidazole C atom of one molecule and 0.018 (3) Å at one of the bridgehead C atoms in the other molecule. Intermolecular O—H...N and N—H...O hydrogen bonds result in the formation of a sheet parallel to the (010) plane.

The mol-ecule of the title compound, C(14)H(10)N(2)O, displays a trans configuration with respect to the C=N double bond. The mol-ecule is roughly planar; the two aromatic rings make a dihedral angle of 9.3 (3)°. Such a planar conformation is induced by the strong intra-molecular O-H⋯N hydrogen bond between the imine and hydroxyl groups.

In the title molecule, C14H10N2O, an intramolecular O—H...N hydrogen bond contributes to the essential coplanarity of the two benzene rings, which form a dihedral angle of 6.04 (18)°.

A silicon hierarchical structure, silicon nanoporous pillar array (Si-NPA), was prepared by a hydrothermal etching method. The architecture of Si-NPA was characterized to be a regular array of micron-sized, quasi-identical and nanoporous silicon pillars with an additional porous layer beneath the array. The pore walls were proved to be consisted of a SiO(x) matrix and dispersive silicon nanocrystallites. An integral reflectivity below 4% was achieved in the wavelength range of 240-2400 nm. Three photoluminescence bands, one blue and two red, were observed at room temperature and attributed to the recombination processes through band-to-band transition and luminescent centers, respectively. The structural and physical properties indicate that Si-NPA might be as both a functional silicon nanostructure and a template for assembling silicon-based nanocomposites in fabricating optoelectronic nanodevices.

In the title compound, [Mn(C8H2NO6)(H2O)2]n, each pyridine-2,4,6-tricarboxyl­ate (tpc) ligand bridges two MnII ions with the formation of polymeric chains located on a twofold rotation axis. Each MnII ion is coordinated by two O and one N atoms from one tpc ligand, two O atoms from another ligand and two water mol­ecules in a distorted penta­gonal–bipyramidal geometry. The Mn—N [2.243 (2) A] and Mn—O [2.206 (2)–2.3123 (16) A] bond lengths are normal. The coordinated water mol­ecules link neighbouring polymeric chains via O—H⋯O hydrogen bonds into a two-dimensional framework parallel to the bc plane.