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A nickel-catalyzed strategy for the synthesis of 1,3-diaryl-6H-pyrazino[2,1-b]quinazolin-6-one was developed. This method enabled us to access valuable pyrazino-fused quinazolinones with tolerance of many functional groups even at room temperature. The desired pyrazino-fused quinazolinones emit strongly in both solution and solid states. Furthermore, the thermally-activated delayed fluorescence (TADF) of 3a was investigated. This study provides an efficient synthetic route for the development of TADF-active pyrazino-fused quinazolinones, thus expanding the application range of this versatile molecular scaffold in optoelectronics. [ABSTRACT FROM AUTHOR]

Rabies is a lethal neurological disease caused by the neurotropic rabies virus (RABV). To investigate the innate immune response in the brain during rabies infection, key gene transcripts indicative of innate immunity in a mouse model system were measured using real-time RT-PCR. Mice were infected via the intracerebral or intramuscular route with either attenuated rabies virus (SRV9) or pathogenic rabies virus (BD06). Infection with SRV9 resulted in the early detection of viral replication and the rapid induction of innate immune response gene expression in the brain. BD06 infection elicited innate immune response gene expression during only the late stage of infection. We measured Na-fluorescein uptake to assess blood-brain barrier (BBB) permeability, which was enhanced during the early stage of SRV9 infection and significantly enhanced during the late stage of BD06 infection. Furthermore, early SRV9 replication increased the maturation and differentiation of dendritic cells (DCs) and B cells in the inguinal lymph nodes and initiated the generation of virus-neutralizing antibodies (VNAs), which cooperate with the innate immune response to eliminate virus from the CNS. However, BD06 infection did not stimulate VNA production; thus, the virus was able to evade the host immune response and cause encephalitis. The rabies virus phosphoprotein has been reported to counteract IFN activation. In an in vitro study of the relationship between IFN antagonism and RABV pathogenicity, we demonstrated that SRV9 more strongly antagonized IFN activity than did BD06. Therefore, there is no positive relationship between the IFN antagonist activity of the virus and its pathogenicity. [ABSTRACT FROM AUTHOR]

Indigoids have received much attention as the candidates of sustainable ambipolar organic semiconductor. However, the low charge carrier mobilities extremely limit their practical applications. Therefore, in-depth understanding of their electronic-structure properties and rational molecular modifications are urgently required. Here, we propose a promising strategy to design ambipolar organic semiconductors based on indigo fragments. Moreover, we predicted the organic crystal structures by evolutionary algorithm combined with DFT-D method. Charge transport properties have been significantly improved for the designed molecules, such as narrower energy gaps, higher electron affinity, larger transfer integrals as well as much smaller reorganization energies for hole and electron. Thusly, remarkable ambipolar charge transport behavior has been predicted, for example, the charge carrier mobilities are up to μ h / μ e = 7.71/5.42 cm 2 V −1 s −1 for NN-indigo-6,6′-2CN and μ h / μ e = 5.15/2.13 cm 2 V −1 s −1 for C 9 -NN-indigo-6,6′-2CN respectively. [ABSTRACT FROM AUTHOR]

Toll-like receptor 22 (TLR22) exists exclusively in aquatic animals and recognizes double stranded RNA (dsRNA). In the present study, a tlr22 gene and its 5′-flanking sequence were cloned from turbot, Scophthalmus maximus , its immune responsive expression was subsequently studied in vivo . The turbot ( sm ) tlr22 gene spans over 5.6 kb with a structure of 4 exon-3 intron and encodes 962 amino acids. The deduced protein shows the highest sequence identity (76.7%) to Japanese flounder Tlr22 and possesses a signal peptide sequence, a leucine-rich repeat (LRR) domain composed of 27 LRR motifs, a transmembrane region and a Toll/interleukin-1 receptor (TIR) domain. Phylogenetic analysis grouped it with other teleost Tlr22s. The interferon-stimulated response element (ISRE) and signal transducer and activator of transcription (STAT) binding site important for the basal transcriptional activity of TLR3 were predicted in the 5′-flanking sequence of smtlr22 gene. Quantitative real-time PCR (qPCR) analysis demonstrated the constitutive expression of smtlr22 mRNA in all examined tissues with higher levels in the head kidney, kidney and spleen. Further, smtlr22 expression was significantly up-regulated following challenge with polyinosinic: polycytidylic acid (poly I:C), lipopolysaccharide (LPS) or turbot reddish body iridovirus (TRBIV) in the gills, head kidney, spleen and muscle, with maximum increases ranging from 2.56 to 6.24 fold upon different immunostimulants and organs. These findings suggest a possible role of Smtlr22 in the immune responses to the infections of a broad range of pathogens that include DNA and RNA viruses and Gram-negative bacteria. [ABSTRACT FROM AUTHOR]

Abstract: The charge transport properties in a series of five-ring-fused thienoacenes are detailedly investigated here. With both high 3-D hole mobilities and good oxidative stability, the thiophene–benzene alternate structures in series B should be better than other two series as p-type organic semiconductors. In addition, a theoretical explanation for the difference between experimental hole mobilities in B-3 and B-3* is provided based on crystal structure prediction. The role of dynamic disorder in C-3 is also investigated here and the results indicate that dynamic disorder plays a crucial role both in the 1-D and 2-D carrier transporting process. [Copyright &y& Elsevier]

Molecules in the vicinity of extended systems, such as metal surfaces, behave in peculiar ways. Their energy levels are broadened, and their molecular properties are so profoundly enhanced that they hardly resemble the ones of the isolated molecule. This is due to dynamical interactions (i.e., interactions that couple excited electronic states) between the molecular, finite system and the extended, infinite system. Since the early days of quantum mechanics, Fermi golden rule has been employed to explain some of the dynamical interactions (such as the broadening of the energy levels). However, a fully quantum-mechanical and ab initio model of these systems remains elusive, in most part due to the computational complexity entailed in the simulations. In this work, we present subsystem time-dependent DFT (TDDFT) simulations of water and benzene molecules as they interact with surfaces of MoS2 monolayer and Au(111). A many-body expansion of the supersystem response function in terms of molecule and surface responses allows us to dissect and describe the dynamical interactions. Not only do we compute and clearly identify terms related to dissipation, broadening, and peak shift, but we also provide a connection between subsystem TDDFT and Fermi golden rule. This work sets the stage for subsystem TDDFT simulations of interfaces relevant to energy materials and nonadiabatic dynamics at such interfaces. [ABSTRACT FROM AUTHOR]

In contrast to many countries where rabies has been well controlled in humans and livestock, even in wildlife, rabies is still endemic in almost regions of China. In Northwest China, rabies transmitted by stray dogs and wild foxes has caused heavy economic losses to local herdsmen, as well as causing numbers of human cases. In this study, as part of an investigation of ways to prevent rabies epidemics in livestock, we report an analysis of domestic cattle and camel rabies cases in Ningxia Hui (NHAR) and Inner Mongolia Autonomous Region (IMAR) and the immune efficacy of canine inactivated rabies vaccines in these animals. We found that rabies viruses from these animals are closely related to dog-hosted China I and fox-associated China III lineages, respectively, indicating that the infections originated from two different sources (dogs and wild foxes). As well as the previously reported Arctic and Arctic-related China IV lineage in IMAR, at least three separate phylogenetic groups of rabies virus consistently exist and spread throughout Northwest China. Since there is no licensed oral vaccine for wild foxes and no inactivated vaccine for large livestock, local canine inactivated vaccine products were used for emergency immunization of beef and milk cattle and bactrian (two-humped) camels in local farms. Compared with a single injection with one (low-efficacy) or three doses (high-cost), a single injection of a double dose of canine vaccine provided low-price and convenience for local veterinarians while inducing levels of virus neutralizing antibodies indicative of protection against rabies for at least 1 year in the cattle and camels. However, licensed vaccines for wildlife and large domestic animals are still needed in China. [ABSTRACT FROM AUTHOR]

Quantum-chemistry methods are used to investigate the effect of phenylamine chromophore on the electronic structure, optical properties, and phosphorescence efficiencies of a series of fac -iridium(III) complexes, Ir-(g0) 3 (1) , meta-substituted Ir compounds [Ir-(g0) 2 -(g1) 1 ] (1a) , [Ir-(g0) 1 -(g1) 2 ] (1b) , [Ir-(g1) 3 ] (1c) and para-substituted Ir compounds [Ir-(g0) 2 -(g1′) 1 ] (2a) , [Ir-(g0) 1 -(g1′) 2 ] (2b) , [Ir-(g1′) 3 ] (2c) , where g0 = l -phenylisoquinolinato, g1 = 4-(isoquinolin-1-yl)- N , N -diphenylbenzenamine, g1′ = 3-(isoquinolin-1-yl)- N , N -diphenylbenzenamine. The calculations show that introduction of phenylamine chromophore at meta position of phenyl ring ( 1a – 1c ) slightly changes the ground-states geometries but largely increases the energy of HOMO and decreases IP values hence improves the ability of hole injection, which is consistent with the experimental report. The introduction of diphenylamine substitutions on the para position ( 2a – 2c ) is effective for extending the π-electron delocalization, which results in strengthening metal-ligand bond and dramatically increasing the HOMO energy. More important, the 2a – 2c have enhanced metal-to-ligand charge transfer 3 MLCT participation in the phosphorescent spectra, decreased the singlet-triplet splitting energy (Δ E S1–T1 ), as well as dramatically small energy differences between the highest occupied orbitals splitting (Δdd occ ) and large lowest unoccupied d-orbitals splitting (Δdd*) at the both S 0 and T 1 geometries, these account for the quantum yield and efficiency of phosphorescence. The calculated ionization potentials (IPs), electronic affinities (EAs), and reorganization energy ( λ ) confirm that the hole and electron injection and transfer ability were enhanced by importing the diphenylamine. Furthermore, based on the analyses of triple energy differences between host and guest, charge carrier mobility, optical overlap, it is found that these Ir complexes maybe good guest materials in CBP. Thus, the introduction of phenylamine at para position is effective approach to obtain highly efficient red phosphorescent emitters. [ABSTRACT FROM AUTHOR]

• The benzoimidazoisoindole derivatives were designed and synthesized. • Structural and spectral analysis of the prepared compounds were investigated. • The target compounds exhibited obvious dual-state emission (DSE) properties. • DFT was carried out to help understand the relationship between electronic structures and photophysical properties. Benzoimidazoisoindoles are key structural motifs, widely found in pharmaceutical drugs and functional materials. However, very few strategies have been developed for the synthesis of benzoimidazoisoindoles, which greatly limited their applications. Herein we report an efficient approach for synthesizing benzoimidazoisoindole derivatives via palladium-catalyzed tandem cyclization of 2-(2-bromophenyl)-1 H -benzo[ d ]imidazoles and isocyanides. Various benzoimidazoisoindoles were prepared in 63–86 % yields under air atmosphere at 100°C. The benzoimidazoisoindoles were characterized by UV–vis, photo-fluorescence, 1H and 13C NMR and HMRS. Furthermore, the single crystal structure of compound 3aa was determined to be of monoclinic system, space group I2/a, with α = 17.0080(4), b = 5.89820(10), c = 29.3286(7) Å, β = 102.948(2)°, V = 2867.34(11) Å3, D c = 1.276 g/cm3 , Z = 8, F(000) = 1168.0, μ (Cu Kα) = 0.599 mm−1, R = 0.0373 and w R = 0.0961. Photophysical property tests demonstrated that the designed benzoimidazoisoindoles exhibited typical dual-state emission (DSE) phenomenon. Density functional theory (DFT) calculation was also conducted to help understand the relationship between electronic structures and photophysical properties. Modified skeleton, the fused system includes benzoimidazoisoindole ring based on the structure–property relationship helps to design new, more effective types of dual-state emission materials. [ABSTRACT FROM AUTHOR]

Combining quantum-tunneling-effect-enabled hopping theory with kinetic Monte Carlo simulation and dynamic disorder effects, the charge transport properties of a series of N-hetero 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-PEN) derivatives with halogen substitutions were studied. Based on the single molecule and the theoretically predicted crystal structure, the electronic structures and nuclear dynamic disorder effects of halogen and aza systems and their impacts on the charge transport behaviors were expounded. On the one hand, this study revealed the regularity of carrier transport by substitution with one or two pyrazine rings from the external toward the internal for benzene rings in TIPS-PEN, suggesting the substitution of two internal pyrazine rings can sharply shrink the hole transport features. Meanwhile, internal pyrazine rings improve the electron transport performance mainly by enhancing air stability and compacting π-stacking. On the other hand, the investigation elaborated the delicate tuning effect of chlorination on two kinds of carrier transports based on aza-TIPS-PEN derivatives, indicating chlorination can effectively equilibrate the electron and hole reorganization energies and decrease the slip distances along the molecular long and short axes in favor of the similarity in the hole and electron transfer integral values, thereby yielding increasingly balanced ambipolar transport characteristic. The coordination of monopyrazine substitution and chlorination on the acene is an effective way to acquire ambipolar transport properties. In addition, the nuclear dynamic disorder effect affects the hole transfer integral more than the electron transfer integral. In the case of the comprehensive consideration of both ease of charge injection and intrinsic transport mobility, both 8,9,10,11-tetrafluoro-6,13-bis((triisopropylsilyl)ethynyl)naphtho[2,3-b]phenazine (2b) and tetrachloro-6,13-bis((triisopropylsilyl)ethynyl)quinoxalino[2,3-b]phenazine (3c) exhibited to be electron-dominant materials, while 8,9,10,11-tetrachloro-6,13-bis((triisopropylsilyl)ethynyl)naphtho[2,3-b]phenazine (2c) showed effective ambipolar transport characteristics with average hole/electron mobility of 3.64/2.21 cm2 V−1 s−1. [ABSTRACT FROM AUTHOR]

Rabies is a neglected zoonotic disease that is preventable in humans by appropriate post-exposure prophylaxis (PEP). However, current PEP relies on polyclonal immune globulin products purified from pooled human (HRIG) or equine (ERIG) plasma that are either in chronic shortage or in association with safety concerns. Here, we present the development of an antibody cocktail, SYN023, made of two novel monoclonal antibodies (MAb) CTB011 and CTB012 that could serve as safer and more cost-effective alternatives to the current RIG products. Both CTB011 and CTB012 are humanized MAbs that bind to non-overlapping epitopes on the rabies virus (RABV) glycoprotein (G) with sub-nanomolar affinities. Sequence analysis revealed that many of the critical residues in binding are highly conserved across different species of lyssaviruses. When combined at a 1:1 ratio, CTB011/CTB012 exhibited neutralization capabilities equivalent or superior to HRIG against 10 North American street RABV isolates in vitro and 15 prevalent Chinese RABV strains in animal models. Finally, SYN023, at a dosage of 0.03 mg/kg, was able to offer the same degree of protection as standard HRIG administration (20 IU/kg) in Syrian hamsters challenged with a highly virulent bat (Tadarida brasiliensis) RABV variant. Taken together, the high-potency and broad-spectrum neutralization demonstrated by SYN023 make it an effective candidate for human rabies PEP consideration. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is an obligate intracellular apicomplexan parasite which is able to infect almost all warm-blooded animals. There is no information about the prevalence and genetic characterization of T. gondii in badgers ( Melogale moschata ) in China. Here, a total of 367 badgers were captured from different cities in Jiangxi province, Southern China. Genomic DNA was extracted from brain tissues of each badgers, and 57 (15.45%) of them were positive for T. gondii by semi-nested PCR of the B1 gene. The positive DNA samples were typed at 11 genetic markers, including 10 nuclear loci (SAG1, 5′-SAG2 and 3′-SAG2, alternative SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1) and an apicoplast locus (Apico), with multilocus polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technology. Among them, 4 were completely typed at all loci, and 2 was genotyped for 9 loci, showing that they belong to ToxoDB#9. This is the first report of prevalence and genetic characterization of T. gondii isolates from badgers in China, which contributes to broader understanding of population structure of T. gondii in China. It is important for the prevention and control of T. gondii infection in wild animals. [ABSTRACT FROM AUTHOR]

Pseudorabies (PR, Aujeszky's disease) is an acute, highly contagious viral disease resulting in major economic losses to the swine industry. PR is endemic in wild and domestic animals, although its natural host is the pig. Here, we report an outbreak of PR in foxes on a fur-producing farm in Yuncheng county, Shandong, China, that were fed pig offal. The diagnosis of PR was based on nervous signs and standard PCR methods and by isolation of PRV from fox brain tissue in Vero cells. The diagnosis was confirmed by an indirect immunofluorescence assay and electron microscopy. Phylogenetic analysis of a partial (804 nt) viral glycoprotein gC gene sequence indicated that it was likely to be a field strain closely related to a cluster of PRV previously identified in China. [ABSTRACT FROM AUTHOR]

Mammalian orthoreoviruses (MRVs) are widespread and infect virtually all mammals. We report here the first case of a natural mutant and reassortant serotype 3 reovirus from mink in China, known as MRV3 SD-14. Whole-genome sequence analysis showed that the MRV3 SD-14 may have resulted from a reassortment involving MRVs that infected swine, humans and mink. Interestingly, the S1 segment, which encodes the viral attachment protein σ1, which influences viral virulence and cell tropism in the host, had a stop codon mutation at amino acid 246. Surveillance of the virulence and evolution of MRVs in humans and other animals deserves more attention. [ABSTRACT FROM AUTHOR]

We describe the isolation and complete genome sequence of a new calicivirus, FBCV-JX12, isolated from a ferret badger ( Melogale moschata). Comparison of FBCV-JX12 with other vesiviruses revealed that it shared the highest amino acid sequence identities of 71.6, 60.5, and 59.3 % in the nonstructural protein, VP1, and VP2, respectively, with MCV-DL2007 (mink calicivirus). Phylogenetic analysis of the whole genomic sequence showed that it clustered most closely with MCV-DL2007 of the genus Vesivirus, but with low nucleotide similarity in the three open reading frames (62.1-68.5 %). [ABSTRACT FROM AUTHOR]

Abstract: A family of N-heteropentacenes acted as promising candidates for organic semiconductor materials is of immense interest. It should be attributed to the following reasons that (1) the positions, numbers and valence-states of N atom in N-heteropentacenes can effectively tune their electronic structure, stability, solubility, and molecular stacking; (2) diverse intermolecular interaction and π-stacking motifs appear in their crystals. The effect of the position and number of the 6-π-pyrazine on their structures and charge-transport properties has been systematically investigated in our previous work (J. Phys. Chem. C 115 (2011) 21416). Therefore, in this work, the study on the role of 8-π-dihydropyrazine with another valence-state N atoms is our focus. Density functional theory, Marcus electron transfer theory and Brownian diffusion assumption coupled with kinetic Monte-Carlo simulation are applied into this investigation. Our theoretical results indicate that in contrast with pyrazine, dihydropyrazine introduced is more helpful for promoting p-type organic semiconductor materials. For molecule 4, hole mobility of its single crystal theoretically reach 0.71cm2 V−1 s−1, and coupled with its fine hole-injection ability, it should be a promising candidate for p-type organic semiconductor materials. Although the lowest triplet-state energies of the molecules studied are very small, introduction of dihydropyrazine is very helpful for increasing the energies. [Copyright &y& Elsevier]