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Nitrogen and sulfur co-doped carbon dots (N,S-CDs) have been widely studied with high quantum yield (QY). The experimental conditions of three different N,S-CDs were optimized. Emission peak position of three different N,S-CDs shown almost remains unchanged or obvious excitation-dependent PL properties, that was likely owed to size distribution. In order to discuss the N,S-CDs stability of photoluminescence property in environment, various experiments such as the photostability, different pH, ionic strengths and temperature were designed. To sum up, three different N,S-CDs exhibited discrepancy property. Molecular interaction of three different N,S-CDs were produced via vary carbon source with human serum albumins have been investigate by various methods. The quenching mechanism, thermodynamic and kinetic parameters, binding sites, electrochemical behavior of three different N,S-CDs with human serum albumins have some different, but conformational change of three different N,S-CDs with human serum albumins alike. The molecular docking had successful applied to study the N,S-CDs interaction with HSA. Different N,S-CDs possessed various characteristic that will have different quenching mechanism when they interaction with human serum albumin, study the mechanism of action at molecular level will help people to choose suitable CDs to apply in nanomedical.

Communicated by Ramaswamy H. Sarma.

Camptothecin (CPT) and 10-hydroxycamptothecin (HCPT) are two anti-tumor agents that cause the tumor cell death by inhibiting the degradation of the cleaved DNA strand. In the current study, we researched the interactions of CPT/HCPT and bovine serum albumin (BSA) with the multi-spectroscopy method, electrochemical method and molecular docking method. The inverse ratio of Ksv and Ka to temperature and the difference in UV–vis absorption indicated that there was a formed complex in both CPT-BSA system and HCPT-BSA system when they titrated into BSA solution, cyclic voltammetry and AC impedance experiments confirmed this phenomenon. The thermodynamic data demonstrated that hydrogen bonding as well as electrostatic interactions might be the leading force when they bound to BSA. The experiments of site competition and molecular docking showed that both CPT and HCPT bind to BSA on site I. Furthermore, the three-dimensional fluorescence, synchronous fluorescence and circular dichroism spectroscopy demonstrated that presence of CPT/HCPT changed the conformation of BSA.

In this study, fluorescence spectroscopy and molecular modeling approaches were employed to investigate the binding of methotrexate to human serum albumin (HSA) under physiological conditions. From the mechanism, it was demonstrated that fluorescence quenching of HSA by methotrexate results from the formation of a methotrexate/HSA complex. Binding parameters calculated using the Stern-Volmer method and the Scatchard method showed that methotrexate binds to HSA with binding affinities in the order 104 L·mol-1 . Thermodynamic parameter studies revealed that the binding reaction is spontaneous, and that hydrogen bonds and van der Waals interactions play a major role in the reaction. Site marker competitive displacement experiments and a molecular modeling approach demonstrated that methotrexate binds with appropriate affinity to site I (subdomain IIA) of HSA. Furthermore, we discuss some factors that influence methotrexate binding to HSA.

A novel bispyrazole, 2,6-bis(5-phenyl-1H-pyrazol-3-yl)-pyridine, was designed and synthesized. The bispyrazole showed extreme selectivity for Ni2+ over other metal ions such as Ag+, Al3+, Ba2+, Ca2+, Cd2+, Co2+, Cr3+, Cu2+, Fe3+, Hg2+, K+, Mg2+, Na+, Pb2+, and Zn2+ in MeOH–H2O solution. The sensing sensitivity and binding properties of the bispyrazole for nickel(II) ion were investigated by fluorescent spectroscopic techniques. It was found that the bispyrazole possessed high selectivity and sensitivity toward Ni2+ over other metal ions. The binding stoichiometry was confirmed as 1:1 (bispyrazole/Ni2+) by Job plot experiment and the linearity of the Benesi–Hildebrand plot. The binding constants K and thermodynamic parameters (ΔH, ΔG, and ΔS) at different temperatures were obtained. Meanwhile, the detection limit of the bispyrazole for Ni2+ was determined to be 3.25 × 10−7 mol L−1.

Six novel difluoroboron complexes with fluoroquinolones were prepared from fluoroquinolones via complexation with boron trifluoride etherate in DMF–CH2Cl2 solution. Their spectroscopic properties were investigated by UV–vis absorption, FTIR, 1H NMR and fluorescence spectroscopic techniques. The results showed that these difluoroboron complexes exhibited the intense fluorescence emission at 401–579 nm under UV visible illumination and possessed a relatively high quantum yield in DMSO solution and solid state. Especially, the difluoroboron complex of Levofloxacin displayed the strongest fluorescence and highest quantum yield (Φu = 0.63) in these difluoroboron complexes, due to its conjugated rigid plane system via four fused six-membered cyclic structures.

Considering the vital role of mitochondria in the anti-cancer mechanism of organic arsenical, the mitochondria-targeted precursor PDT-PAO-TPP was designed and synthesized. PDT-PAO-TPP, as a delocalization lipophilic cation (DLCs) which mainly accumulated in mitochondria, contributed to improve anti-cancer efficacy and selectivity towards NB4 cells. In detail, PDT-PAO-TPP inhibited the activity of PDHC resulting in the suppression of ATP synthesis and thermogenesis disorder. Additionally, the inhibition of respiratory chain complex I and IV by short-time incubation of PDT-PAO-TPP also accelerated the respiration dysfunction and continuous generation of ROS. These results led to the release of cytochrome c and activation of caspase family-dependent apoptosis. Different from the mechanism of PDT-PAO in HL-60 cells, it mainly induced the mitochondrial metabolic disturbance resulting in the intrinsic apoptosis via inhibiting the activity of PDHC in NB4 cells, which also implied that the efficacy exertion of organic arsenical was a complex process involved in many aspects of cellular function. This study systematically clarifies the anti-cancer mechanism of mitochondria-targeted organic arsenical PDT-PAO-TPP and confirms the new target PDHC of organic arsenicals, which further supports the organic arsenical as a promising anticancer drug.

A stepwise seeded growth route for the preparation of silver nanoparticles (AgNPs) is reported. In the process, silver nitrate was used as a precursor, with sodium borohydride as a reducing agent and trisodium citrate as both a reductant and stabilizer. The AgNPs were characterized using several methods, including UV–vis spectroscopy, X-ray diffraction and transmission electron microscopy. The prepared AgNPs were quasi-spherical and crystalline, with an average diameter of 21 nm. Interactions between the AgNPs and bovine serum albumin (BSA) were investigated using UV–vis, fluorescence spectroscopy and synchronous fluorescence spectroscopy (SFS). It was proved that the quenching mechanism is a static process. The binding constants and number of binding sites were calculated. The thermodynamic parameters implied that the binding process was spontaneous and the main driving force of the interaction was electrostatic. The results of the SFS indicated that the conformational change of BSA was induced by AgNPs. Copyright © 2016 John Wiley & Sons, Ltd.

The fluorinated β-diketone ligand, 4,4,4-trifluoro-1-(6-methoxy- naphthalen-2-yl)-butane-1,3-dione (HL), and its ternary europium (III) complexes using water (H2O), 2,2-dipyridine (Bipy), 1,10-phenanthroline (Phen) and 4′-phenyl-terpyridine (Phterpy) as the secondary ligand were synthesized and characterized by elemental analysis, FT-IR, 1H NMR, UV–vis absorption, ESI–MS and fluorescence spectroscopic techniques. All these europium complexes exhibited the characteristic emission bands that arise from the 5D0 → 7FJ (J = 0–4) transitions of the europium ion in solid state. Based on their emission spectra and lifetimes, the Judd–Ofelt intensity parameters (Ω2 and Ω4), the radiative decay rate Arad, the nonradiative rates Anrad, and the quantum efficiency (η) were determined and compared. The ternary complexes, EuL3·Bipy, EuL3·Phen and EuL3·Phterpy, exhibited much higher quantum efficiencies and lifetime values, which can be attributed to the displacement of water molecules from the coordination sphere by the heterocyclic nitrogen donors. Especially, the complex EuL3·Phen exhibited the longest lifetime τ (0.704 ms) and the highest luminescence quantum efficiency η (47.9%) among these complexes. Meanwhile, complexes EuL3·Bipy, EuL3·Phen and EuL3·Phterpy also displayed higher Ω2 values than the complex EuL3·2H2O, indicating their hypersensitive character of the 5D0 → 7F2 transition and a highly polarizable chemical environment around the europium(III) ion.

Naringenin (Nar) is a flavanone compound found in grapefruits that is endowed with diverse pharmacological and biological activities. Here, the interaction between Nar and human serum albumin (HSA) was investigated via various methods, including fluorescence spectroscopy, electrochemical methods and molecular docking. The Stern-Volmer quenching constants inversely correlated with temperature, demonstrating that the fluorescence quenching about HSA-Nar system is initiated by the formation of a compound, which has confirmed by electrochemical measurements. Three-dimensional fluorescence demonstrated that Nar induces the slight unfolding of the polypeptides of HSA. The calculated thermodynamic parameters suggesting that the binding of Nar to HSA is spontaneous, and the mainly force is electrostatic interactions. In addition, site marker competitive experiments indicated that Nar binds to HSA both on site I (subdomain IIA) and site II (subdomain IIIA), with higher affinity to the latter one, consistence with molecular docking. Furthermore, the fluorescence resonance energy transfer (FRET) experiment showed the binding distance (r) is 2.65 nm. And the effects of metal ions on the HSA-Nar system are also discussed.

Some novel difluoroboron bis-β-diketonates containing a pyridyl moiety were synthesized from diethyl 2,6-pyridinedicarboxylate via Claisen condensation with the corresponding aryl methyl ketones and followed by complexation with boron trifluoride etherate. Their spectroscopic behaviors were studied by FTIR, 1H NMR, UV–Vis, and fluorescence spectroscopic techniques. The results indicated that difluoroboron bis-β-diketonates exhibited violet or blue fluorescence emission at 428–454 nm under UV illumination in DMSO and possessed high extinction coefficients. It was found that the nature of the substituents at benzene ring in bis-β-diketone ligands had a significant impact on the photoluminescence behaviors of difluoroboron complexes. The complex 5b exhibited the strongest photoluminescence intensity and highest quantum yield (Φ u = 0.93), due to two strong electron-donating methoxyl moieties in molecule and the compound 4b displayed the lowest photoluminescence intensity and quantum yield, assigned to the heavy atom effect of the chlorine atom in its molecule. The photoluminescence intensity and quantum yield of these difluoroboron complexes decreased in the sequence, 5b > 2b > 1b > 3b > 4b.

Palmatine, an isoquinoline alkaloid, is an important medicinal herbal extract with diverse pharmacological and biological properties. In this work, spectroscopic and molecular modeling approaches were employed to reveal the interaction between palmatine and DNA isolated from herring sperm. The absorption spectra and iodide quenching results indicated that groove binding was the main binding mode of palmatine to DNA. Fluorescence studies indicated that the binding constant (K) of palmatine and DNA was ~ 10(4)L·mol(-1). The associated thermodynamic parameters, ΔG, ΔH, and ΔS, indicated that hydrogen bonds and van der Waals forces played major roles in the interaction. The effects of chemical denaturant, thermal denaturation and pH on the interaction were investigated and provided further support for the groove binding mode. In addition to experimental approaches, molecular modeling was conducted to verify binding pattern of palmatine-DNA.

“Authorized Shared Access” (ASA) is a spectrum management policy which enables the secondary system to opportunistically utilize the licensed spectrum of the primary systems. In the coexistence of LTE-A system with primary systems, one of the constituent cells of the CoMP cooperating set may be affected because it has to vacate the ASA frequency for it overlaps with the protected area of the primary system. As a result, the CoMP cooperating set will be changed, and the operation of the CoMP can’t be continued execution. In this case, the UE’s QoS can’t be guaranteed and even the UE experiences call drop when using the traditional method. In this paper, by utilizing a central controller, we propose an efficient method for managing CoMP cooperating set on the ASA spectrum. The change information about the affected cell is sent to the serving cell of the CoMP through the central controller in advance. Then, the serving cell may reselect a new CoMP cooperating set or determine CoMP information indicating whether the CoMP cooperating set will be continued based on this change information, which effectively ensures continued execution of CoMP and the UE’s QoS. Simulation results show that the proposed method can provide better performance compared with the traditional method.

Quercetin and naringenin are polyphenolic flavonoids obtained from plant sources. A comparative study of their structure–activity relationships (SAR) has been carried out by multiple methods. Spectroscopy experiments show that quercetin intercalates into the double helix of deoxyribonucleic acid (DNA), while naringenin displays a groove binding mode. Molecular docking studies visually display different binding modes, interaction forces and binding regions while electrochemistry experiments indicate the main factor that effects the DNA–drug interaction during the electrochemical process. Antioxidant assay was performed to find out the difference in their anti-oxidative ability. The results obtained from all these experimentations illustrate that the presence of a double bond in ring A of quercetin is very important to maintain its structural planarity, which influences its binding mode, the main interaction force and the control step in electrochemistry experiments. Quercetin showed better antioxidant properties as compared to naringenin which may be attributed to the presence of a greater number of hydroxyl groups. These findings give an understanding of their structure–activity relationships which may be helpful in the design of analogs of these flavonoids and their application in drug and food industries.

Coptisine, an isoquinoline alkaloid, is an important medicinal herbal extract with diverse pharmacological and biological activities. Based on these considerations, an explorative study of the interaction of coptisine with calf thymus DNA (ctDNA) was conducted using multispectroscopic, electrochemical and molecular modeling techniques under simulative physiological conditions. Absorption spectra and iodide quenching experiments indicated that intercalation was the main DNA binding mode for coptisine. Fluorescence studies revealed that this interaction process is predominantly a dynamic process. This was further confirmed in a difference absorption spectrum and in electrochemical studies. The apparent activation energy, Ea, remained largely constant at different temperatures. DNA chemical denaturation was used to further investigate the interaction and provided further support for the intercalation. Furthermore, CD spectroscopy confirmed that coptisine not only interacted with the ctDNA, but it also perturbed ctDNA structure. In addition to experimental approaches, molecular modeling was used as a tool to verify and expand the experimental outcomes.

Tremendous research efforts have been dedicated to fabricating high-quality Zn-doped CdTe quantum dots (QDs) for any potential biomedical applications. In particular, the correlation of issues regarding how QDs interact with DNA is of greatest importance. Herein, a pH-responsive study of the interactions between CdTe:Zn

The rare earth salts of heteropoly have been widely applied in many fields. In this study, the biological activity of rare earth tungstoarsenate heteropolyoxometalates K11[Ln(AsW11O39)2]·xH2O (abbr. LnW11, Ln = La (x = 24), Nd (x = 17), and Sm (x = 19)) were investigated by spectroscopic methods including fluorescence spectroscopy and UV-vis absorption spectroscopy at different temperatures. In the mechanism discussion, it was proved that the fluorescence quenching of bovine serum albumin (BSA) by LnW11 is initiated by complex formation. The thermodynamic parameters suggested that the binding of LnW11 to BSA is spontaneous, and the mainly force is electrostatic interactions. Site marker competitive experiments demonstrated that LaW11 binds with high affinity to site I (subdomain IIA) of BSA; but SmW11 and NdW11 bind with affinity to both site I (subdomain IIA) and site II (subdomain IIIA) of BSA. The results of synchronous fluorescence spectrum indicate that the secondary structure of BSA molecules was changed in the presence of LnW11. In addition, the binding parameters, binding site number, and effect of metal ions on LnW11-BSA were also discussed.

A new tris-β-diketone ligand, 2-[4,6-bis-(1-benzoyl-2-oxo-2-phenyl-ethyl)-[1,3,5]triazin-2-yl]-1,3-diphenyl-propane-1,3-dione ( H 3 L ), and its trinuclear europium complexes, Eu 3 (DBM) 6 L ( C1 ), Eu 3 (DBM) 6 (Bipy) 3 L ( C2 ) and Eu 3 (DBM) 6 (Phen) 3 L ( C3 ) were synthesized and their spectroscopic behaviors were studied by FT-IR, 1 H NMR, UV–vis and photoluminescence spectroscopic techniques. These europium complexes exhibited the characteristic emission bands that arise from the 5 D 0 → 7 F J ( J = 0–4) transitions of the europium ion in solid state. The Ω 2 and Ω 4 intensity parameters, lifetime ( τ ) and luminescence quantum yield ( η ) were calculated according to the emission spectra and luminescence decay curves in solid state. The results indicated that these trinuclear europium complexes displayed a longer lifetime ( τ ) and higher luminescence quantum efficiency ( η ), especially complexes C2 ( τ = 0.820 ms, η = 46.5%) and C3 ( τ = 0.804 ms, η = 47.4%), which due to the effect of two additional europium ion lumophors and the introduction of the third ligands, Bipy or Phen in trinuclear complexes. Their Ω 2 values demonstrated that the europium ion in these complexes is in a highly polarizable chemical environment.

Six new bis-β-diketones (RCOCH2CO-C7H7N-COCH2COR) were synthesized from 3,5-diacetyl-2,6-dimethylpyridine via Claisen condensation with the corresponding esters, and then reacted with boron trifluoride etherate to afford difluoroboron bis-β-diketonate derivatives. Their spectroscopic properties were investigated by UV–vis, FTIR, 1H NMR and fluorescence spectroscopic techniques. It was found that these boron complexes exhibited violet or blue fluorescence emission at 422–445 nm and possessed high extinction coefficients. The results indicate that the extending π-conjugation can increase the fluorescence intensity and quantum yield for these boron complexes. Especially, the compound 2b displayed the stronger fluorescence intensity and the highest fluorescence quantum yield (Φu = 0.94) in these boron compounds. However, compounds 2c and 2d had the lower fluorescence intensity and quantum yield as a result of the heavy atom effect of the chlorine atom in the molecules.

In order to enhance its interaction efficiency with biomacromolecules for the usage as a therapeutic agent, we have conjugated morin, an antioxidant activity and anti-tumor drug, with citrate-coated Au nanoparticles (M-C-AuNPs). M-C-AuNPs were prepared by reducing chloroauric acid using trisodium citrate in the boiling condition, and the resulted M-C-AuNPs were characterized by UV–vis absorption spectroscopy, Transmission Electron Microscopy (TEM), X-ray diffraction (XRD) and FTIR analysis. In this article, UV–vis absorption spectroscopy in combination with fluorescence spectroscopy, and circular dichroism (CD) spectroscopy were employed to investigate the interactions between M-C-AuNPs and bovine serum albumin (BSA), C-AuNPs and BSA in a phosphate buffer at pH 7.4. By comparing the quenching constant KSV, effective quenching constant Ka, binding constant Kb and the number of binding sites n, it is clearly suggested that M-C-AuNPs could enhance the binding force of morin with BSA, which would pave the way for the design of nanotherapeutic agents with improved functionality.

Tight junctions (TJs) are sealing complexes between adjacent epithelial cells, functioning by controlling paracellular passage and maintaining cell polarity. These functions of TJs are primarily based on structural integrity as well as dynamic regulatory balance, indicating plasticity of TJ in response to external stimuli. An indispensable role of TJs involved in pathogen infection has been widely demonstrated since disruption of TJs leads to a distinct increase in paracellular permeability and polarity defects which facilitate viral or bacterial entry and spread. In addition to pathological changes in TJ integrity, TJ proteins such as occludin and claudins can either function as receptors for pathogen entry or interact with viral/bacterial effector molecules as an essential step for characterizing an infective stage. This suggests a more complicated role for TJ itself and especially specific TJ components. Thus, this review surveys the role of the epithelial TJs involved in various pathogen infections, and extends TJ targeted therapeutic and pharmacological application prospects.

Three novel europium complexes with 1-(4-tert-butylphenyl)-3-(2-naphthyl)-propane-1,3-dione (TNPD) and 2,2-dipyridine (Bipy) or 1,10-phenan-throline (Phen) were synthesized and confirmed by FT-IR, 1H NMR, UV–vis absorption and elemental analysis. Photoluminescence behavior of complexes Eu(TNPD)3, Eu(TNPD)3⋅Bipy and Eu(TNPD)3⋅Phen were investigated in detail. Their emission spectra exhibited the characteristic emission bands that arise from the 5D0 → 7FJ (J = 0–4) transitions of the europium ion in solid state. Meanwhile, the results of their lifetime decay curves indicated that only one chemical environment existed around the europium ion. The intrinsic luminescence quantum efficiency (η) and the experimental intensity parameters (Ωt) of europium complexes were determined according to the emission spectra and luminescence decay curves in solid state. The complex Eu(TNPD)3⋅Phen showed much longer lifetime (τ) and higher luminescence quantum efficiency (η) than complexes Eu(TNPD)3 and Eu(TNPD)3⋅Bipy.

This paper exploring the site-selective binding of jatrorrhizine to human serum albumin (HSA) under physiological conditions (pH = 7.4). The investigation was carried out using fluorescence spectroscopy, UV–vis spectroscopy, and molecular modeling. The results of fluorescence quenching and UV–vis absorption spectra experiments indicated the formation of the complex of HSA–jatrorrhizine. Binding parameters calculating from Stern–Volmer method and Scatchard method were calculated at 298, 304 and 310 K, with the corresponding thermodynamic parameters ΔG, ΔH and ΔS as well. Binding parameters calculating from Stern–Volmer method and Scatchard method showed that jatrorrhizine bind to HSA with the binding affinities of the order 104 L mol−1. The thermodynamic parameters studies revealed that the binding was characterized by negative enthalpy and positive entropy changes and the electrostatic interactions play a major role for jatrorrhizine–HSA association. Site marker competitive displacement experiments and molecular modeling calculation demonstrating that jatrorrhizine is mainly located within the hydrophobic pocket of the subdomain IIIA of HSA. Furthermore, the synchronous fluorescence spectra suggested that the association between jatrorrhizine and HSA changed molecular conformation of HSA.

Five new difluoroboron complexes with 4-pyridyl-β-diketones were synthesized and their structures were confirmed by elemental analysis, IR, 1H NMR, ESI-MS and UV–vis spectroscopy. Their photoluminescence behavior was studied in DMF solution and solid state. The quantum yields (Φu) of complexes 2a–2e in DMF solution were measured relative to quinine sulfate and their lifetime values (τ) were calculated according to the luminescence decay curves in the solid state. From these data, the difluoroboron complexes exhibited the excellent photoluminescence properties. Especially, the complexes 2d and 2e displayed the stronger photoluminescence intensity, much higher quantum yield and longer lifetime value as compared to complexes 2a, 2b and 2c. The results indicate that the substituents at the 4-position on benzene ring have a significant impacts on the photoluminescence properties of the difluoroboron complexes.

Preparation and photoluminescence behavior of four new europium (III) ternary complexes with β-diketones (1-(6-methoxy-naphthalen-2-yl)-3-phenyl-propane-1,3-dione (MNPPD) and 1-(4-tert-butyl-phenyl)-3-(6-methoxy-naphthalen-2-yl)-propane-1,3-dione (BPMPD)) and 2,2-dipyridine (Bipy) or 1,10-phenanthroline (Phen) were reported, in the solid state. Complexes Eu(MPPD) 3 ·Bipy, Eu(BMPD) 3 ·Bipy, Eu(MPPD) 3 ·Phen and Eu(BMPD) 3 ·Phen were characterized by elemental analysis, FT-IR, 1 H NMR, UV–vis absorption. The emission spectra show narrow emission bands that arise from the 5 D 0 → 7 F J ( J = 0–4) transitions of the europium ion. Based on the emission spectra and luminescence decay curves in solid state, the intensity parameters ( Ω t ), lifetime ( τ ) and emission quantum efficiency ( η ) were determined. The Ω 2 values indicate that the Eu(III) ion in these complexes is in a highly polarizable chemical environment. Complexes Eu(MPPD) 3 ·Bipy and Eu(MPPD) 3 ·Phen showed a longer lifetime ( τ ) and a higher luminescence quantum efficiency ( η ), which indicated that the energy transfer to the europium ion from MNPPD ligand is more efficient than that from BPMPD ligand.

The member of the kinesin-14 subfamily, KIFC1, is a carboxyl-terminal motor protein that plays an important role in the elongation of nucleus and acrosome biogenesis during the spermiogenesis of mammals. Here, we had cloned and sequenced the cDNA of a mammalian KIFC1 homologue (termed ec-KIFC1) from the total RNA of the testis of the reptile Eumeces chinensis. The full-length sequence was 2,339 bp that contained a 216 bp 5'-untranslated region (5'UTR), a 194 bp 3'-untranslated region (3'UTR) and a 1,929 bp open reading frame that encoded a special protein of 643 amino acids (aa). The calculated molecular weight of the putative ec-KIFC1 was 71 kDa and its estimated isoelectric point was 9.47. The putative ec-KIFC1 protein owns a tail domain from 1 to 116 aa, a stalk domain from 117 to 291 aa and a conserved carboxyl motor domain from 292 to 642 aa. Protein alignment demonstrated that ec-KIFC1 had 45.6, 42.8, 44.6, 36.9, 43.7, 46.4, 45.1, 55.6 and 49.8 % identity with its homologues in Mus musculus, Salmo salar, Danio rerio, Eriocheir sinensis, Rattus norvegicus, Homo sapiens, Bos taurus, Gallus gallus and Xenopus laevis, respectively. Tissue expression analysis showed the presence of ovary, heart, liver, intestine, oviduct, testis and muscle. The phylogenetic tree revealed that ec-KIFC1 was more closely related to vertebrate KIFC1 than to invertebrate KIFC1. In situ hybridization showed that the ec-KIFC1 mRNA was localized in the periphery of the nuclear membrane and the center of the nucleus in early spermatids. In mid spermatids, the ec-KIFC1 had abundant expression in the center of nucleus, and was expressed in the tail and the anterior part of spermatids. In the late spermatid, the nucleus gradually became elongated, and the ec-KIFC1 mRNA signal was still centralized in the nucleus. In mature spermatids, the signal of the ec-KIFC1 gradually became weak, and was mainly located at the tail of spermatids. Therefore, the ec-KIFC1 probably plays a critical role in the spermatogenesis of E. chinensis.

In this paper, we propose a novel model of three points named TP for location estimation in wireless sensor networks (WSNs) with random deployment of anchor nodes. In this model, we select three anchor nodes which have the strongest received signal strength (RSS) for location estimation, the centroid algorithm and the method of intersection of judgment are used to estimate the location of unknown nodes. To further exploit three nearest intersection points in TP, the enhanced TP (ETP) is proposed. The simulation results show that the proposed models outperform MMSE and BML in terms of the localization accuracy for WSNs. Moreover, the localization accuracy of the proposed models in scenario 2 with random deployment of anchor nodes are better than in scenario 1 with planned deployment of anchor nodes. Additionally, compared with MMSE and BML, ETP and TP can reduce the environmental impact on location estimation.

Anchoring the external prestressing to the bridge end block is one of the key issues for strengthening of existing concrete bridges. This paper presents an innovative technique to fix steel brackets to the sides of the end block by two transverse pretensioned through-rods and three expansion bolts in both friction and shear pattern. In order to validate the technique, two steel reinforced concrete specimens (J1 and J2) fixed with experimental steel brackets are prepared and an experiment investigation has been carried out. Two sudden failures have been observed. The failure patterns of expansion bolts in J1 are pullout failure and shear failure, and two transverse pretensioned through-rods have large yield deformation. The failure patterns of expansion bolts in J2 are similar, but the failure patterns of two transverse pretensioned through-rods are shear fracture. The relationship of force and slip is linear but with two different slope when the load less than 2000kN in both J1 and J2.

In this paper, the Rapid Chloride Permeability Test (RCPT)-ASTM C1202-91 and Conductance test were employed to measure the effect of curing time on the chloride penetration resistance of concrete. The results indicate that the concrete specimens with longer curing time have higher chloride penetration resistance no matter the concrete with or without mineral admixtures, the concrete conductance has the similar variation trend and similar mathematical descriptions as the chloride diffusion coefficient D with the passage of curing time, and it is a very useful method to measure concrete conductance to estimate the chloride permeability variation at different curing or exposure time.

SummaryObjective To study the efficiency of letrozole, an aromatase inhibitor, in endometrial preparation for cryopreserved–thawed embryo transfer (FET) in women with polycystic ovarian syndrome (PCOS). Design Retrospective observational study. Patients One hundred and twenty patients with PCOS who met the inclusion criteria for the study. Measurements We assessed in vitro fertilization outcomes in one hundred and twenty patients with PCOS (148 cycles) who were prepared for and underwent FET between June 2011 and December 2012. Patients were prepared for FET using artificial hormone cycles induced with oestrogen and progesterone supplementation (n = 76), letrozole stimulation (n = 40) or hMG stimulation (n = 32). Results There were no differences in demographic characteristics between the groups, except that the letrozole group had a higher incidence of embryo transfer failure in the past. The letrozole stimulation group had a significantly higher maximal endometrial thickness and significantly higher rates of clinical pregnancy per transfer, ongoing pregnancy per transfer and implantation, compared with the artificial and hMG stimulation groups. Differences in these parameters between the artificial and hMG stimulation groups were not significant. Conclusion Using letrozole stimulation in endometrial preparation for cryopreserved–thawed embryo transfer in patients with PCOS may be associated with better outcomes than using hormonal manipulation or hMG stimulation.

Curcumin is a polyphenolic bioactive compound found in the spice turmeric endowed with diverse pharmacological and biological activities. In this study, fluorescence spectroscopy in combination with UV-Vis absorbance spectroscopy was employed to investigate the high affinity binding of curcumin to herring sperm DNA (hs-DNA). From the series of studies undertaken in the present program, for example, steady-state emission; absorption; the effect of denaturants; competition experiment; and anion (iodide) ion-induced fluorescence quenching; the mode of binding of curcumin into the DNA helix has been substantiated to be principally intercalative. Binding parameters calculating from Stern-Volmer method and Scatchard method showed that curcumin bind to hs-DNA with the binding affinities of the order 10(4 )L mol(-1). The effects of ionic strength, chemical denaturants, thermal denaturation and pH were studied to show the factors of the interaction, and provided further support for the intercalative binding mode. In addition, the methods and techniques used in the present work can also be exploited to study the interaction of curcumin with other biological, biomimicking assemblies and drug delivery vehicles, and so forth.

In this paper, the effect of pore structure on the chloride ions ingress into concrete was investigated. The most probable diameter was measured by Mercury intrusion porosimetry (MIP) and the total porosity was measured by evaporative water method (EWM). The results indicate that the most probable diameter by MIP has better linear relationship with chloride diffusion coefficient than the total porosity by EWM, the most probable diameter has significant influence on chloride diffusivity, and the smaller most probable diameter will lead to higher chloride penetration resistance.

Resveratrol (RSV), a natural polyphenolic antioxidant, has been considered an anticarcinogenic agent as it triggers tumor cell apoptosis through activation of the mitochondrial pathway. In our study, the effects of RSV on mitochondria, especially on the mitochondrial permeability transition (MPT) process, were investigated by multiple methods. We found that RSV induced a collapse of membrane potential and matrix swelling related to MPT. We further demonstrated that Ca²⁺ was necessary for this RSV-induced MPT opening. In addition, RSV induced the inner membrane permeabilization to H⁺ and K⁺, the depression of respiration and changes in membrane fluidity. The results suggested that RSV-induced MPT was accompanied by mitochondrial dysfunction. But the prohibition on lipid peroxidation and different effects of low- and high-dose RSV on membrane fluidity and respiration showed that the interaction of RSV and the mitochondria could not be the result of a single simple mechanism.

Process design grants the quality connotation to products. This paper was to investigate the correlation between changes of chemical fingerprints of Andrographis Herba preparation and its pharmacological activity, and set up the bridge between key process and quality attributes. By referring to the preparation process of Andrographis Herba. preparation (extracting-concentrating-drying-granulation), HPLC fingerprints were employed to determine the difference of the effective materials of the intermediate micro components. Cluster analysis results indicated that the extraction link had great influence on quality connotation variation of Andrographis Herba preparation. The pharmacological activity of various intermediates was continuously decreased in the models of DPPH antioxidant activity and LPS-induced anti-inflammatory activity in mice peritoneal macrophages. Traditional high temperature treatment process was detrimental to its clinical effect from the curve equation between the key process parameters and pharmacodynamic activity. Partial least square (PLS) was used to construct spectrum-efficiency model equation, and it was verified that this equation could accurately predict the relationship between fingerprints and pharmacological activity, which would facilitate the subsequent evaluation of quality attributes and provide scientific basis for further quality control of the whole process.

Aim: We conducted the present study to assess health-related quality of life (HRQoL) among bone cancer patients after surgical treatment in one large teaching hospitals in China, and assess the risk factors for improving the physical or mental HRQoL. Methods: 344 eligible adult patients who were admitted to the hospital with malignant bone tumors during the period of Jun. 2008 to Dec. 2011, and a reference group with 361 health cases was recruited in the same hospital during the same period. All 344 patients were followed up for one year. The HRQoL before treatment and after one year was evaluated with the Medical Outcome Short Form 36 (SF-36). Results: All 8 domains of HRQoL had the lowest scores greatly improved over the first year after discharge. However, the patients still had significantly lower scores in every domain than the reference group one year after discharge. Age and type of surgery were associated with HRQoL in the mental domain. Conclusion: The HRQoL of patients with malignant bone tumors greatly improved one year after the treatment. This study also highlighted the utility of HRQoL assessment for prognostic evaluation of patients after surgical treatment for bone cancer.

The interaction between morin and bovine serum albumin (BSA) was studied using molecular spectroscopic approach at different temperatures under imitated physiological conditions. Quenching of intrinsic tryptophanyl fluorescence of BSA with increasing morin concentration is the actuating tool in the analysis. The obtained quenching mechanisms, binding constants, binding sites and corresponding thermodynamic parameters at different temperatures indicate that the hydrophobic interaction play a major role in the morin-BSA association. Binding affinity between morin and BSA was determined using Scatchard equation and the modified Stern-Volmer equation, and the corresponding Structure-affinity relationships of flavonoids were discussed. Site marker competitive displacement experiments demonstrated that morin binds with high affinity to site II (subdomain IIIA) of BSA. Furthermore, the circular dichroism spectral results indicated that the conformation of BSA changed in the presence of morin. In addition, the effect of some common metal ions on the binding constant between morin and BSA was examined.

Aims: We performed this retrospective study to evaluate the value of clinicopathological factors and a novel molecular marker stathmin in predicting treatment response to neoadjuvant chemotherapy (NCT) with docetaxel-containing regimens in patients with locally advanced breast cancer. Methods: Fifty-four consecutive locally advanced patients receiving docetaxel-containing NCT between January 2006 and July 2010 in Zhejiang Cancer Hospital were included. The expression levels of estrogen receptor (ER), progesterone receptor (PgR), epidermal growth factor receptor-2 (HER-2), and p53 were detected by immunohistochemistry, while expression of stathmin mRNA was measured by Quanti-Gene assay. Results: The overall clinical objective response (cOR) rate was 75.9% (41/54) in breast. A total of 34 patients (63.0%) experienced pathological OR (pOR), with pathological complete remission (pCR) rate of 20.4% (11/54) in breast and 16.7% (9/54) in both breast and axilla. In univariate analysis, there were associations of pOR in both breast and axilla with age (p=0.054), ER status (p=0.059), subtypes (p=0.062), p53 (p=0.030), and stathmin expression (three terciles) (p=0.039). Mean expression of stathmin in pOR group was 0.410, compared with that in no response group of 0.556 (p=0.051 by Student's t-test). Similarly, a lower expression of stathmin might represent a higher pCR rate (p=0.061). Moreover, the LOWESS smoothing plot showed the same trend, that is, that tumor with a lower level of stathmin expression had a higher probability of response to docetaxel-containing NCT. After multivariate adjustment, both ER and stathmin remained significant with hazard ratio of 4.58 (95% CI: 1.11–18.94, p=0.036) and 2.94 (95% CI: 1.26–6.86, p=0.012), respectively. Conclusions: In conclusion, ER and stathmin were independent predictive factors for NCT with docetaxel-containing regimens.

The presented study mainly focused on investigating detailed engineering properties of municipal solid waste incineration residues as road construction materials with different application classes. Also, the leachability of heavy metals and salts in the residues as a function of the ratio of liquid and solid was tested. The Chinese specifications about road construction materials were employed to evaluate the application capacity of the waste incineration residues. The obtained results indicate that bottom ash basically complies with the technical requirements for road base and sub-base materials with exception of the low compataclity and high organic content of the fine fraction. The toxicity test showed that bottom ash can satisfy the limit values of heavy metals and salts that was established by Chinese specification for hazard solid waste. For the application of the ash in road base, it should be mixed with other materials to improve the compataclity. Pretreatment of fine fraction of bottom ash to remove organic matter is necessary.

Wind as a renewable energy, is typical of clean energy, and wind power generation has good social and environmental benefits, which has developed rapidly in worldwide. In this paper, the problems of China's wind power industry and the world wind power industry experience are discussed. The distribution of resources for wind energy, wind energy resource assessment, monitoring and forecasting system, wind industry, policy influencing factors are detailed analysis, and based on China conditions for its development were discussed.

In this study, plain and mineral admixture (slag, fly ash and silica fume) modified concrete prisms were made with three water-to-binder ratios (w/b), and four test methods (Rapid Chloride Permeability Test-ASTM C1202-91, AC Conductance Test, 150-days Ponding Test, Alternate Wetting and Drying Test by cyclic loading with salt solution and drying) were employed to measure the concrete prisms’ chloride penetrability. The effects of mineral admixtures on the concrete chloride permeability were discussed, and the correlation of results separately obtained from the four test methods were analyzed. The experiment results indicate that blending concrete is beneficial with regard to the resistance against chloride ion penetration, and good linear ralationship between charge passed and innitial current, charge passed and conductance, charge passed and chloride diffusion coefficients by 150-days Ponding Test, charge passed and diffusion coefficients by Alternate Wetting and Drying Test were obtained.

The aim of this study was to detect the pretreatment serum protein profiles of breast cancer patients by mass spectrometry (MS) to screen candidate tumor biomarkers, which will supply a simple, accurate, and minimally invasive method to predict the axillary lymph node metastasis of breast cancer. We used magnetic bead-based weak cation-exchange chromatography followed by matrix-assisted laser desorption and ionization time-of-flight MS to detect proteins in the sera of 54 cases of axillary node-negative breast cancer, 47 cases of axillary node-positive breast cancer, and 101 healthy controls. The protein profiles were analyzed to screen tumor biomarkers and lymph node metastasis-associated proteins to establish and verify a diagnostic model. Comparison of the protein profiles between the two cancer groups resulted in a total of 111 discriminate m/z peaks that were associated with breast cancer. Furthermore, 40 discriminate m/z peaks were detected between breast cancer patients with and without axillary node metastases. Four protein m/z peaks at 5,643, 4,651, 2,377, and 2,240 were used to construct a diagnosis model, and cross-validation indicated that breast cancer with and without axillary node metastasis was identified with 87.04% sensitivity (47/54), 87.23% specificity (41/47), and 87.13% accuracy (88/101). These proteins could potentially be used as predictive biomarkers to distinguish between breast cancer patients with or without lymph node metastasis.

The binding of rifampicin (RFP), an anti-tuberculosis agent, to bovine serum albumin (BSA) was studied at physiological conditions (pH=7.40) by a spectroscopic approach. In the discussion of the quenching mechanism, it was proved that the fluorescence quenching of BSA by RFP is a result of the formation of a RFP–BSA complex. Binding parameters were determined using the modified Stern-Volmer equation and Scatchard’s equation to provide a measure of the binding affinity between RFP and BSA. The resulting thermodynamic parameters ΔG, ΔH, and ΔS at different temperatures indicate that electrostatic interactions play a major role in RFP–BSA association. Site marker competitive displacement experiments demonstrate that RFP binds with high affinity to the site I (subdomain IIA) of BSA. Furthermore, the effect of metal ions on the RFP–BSA system was studied, and the specific binding distance r (3.38 nm) between donor and acceptor (RFP) was obtained according to the fluorescence resonance energy transfer (FRET).

In this study, concrete prisms were made with three mineral admixtures: fly ash, blast furnace slag or silica fume and with three water-to-binder ratios(w/b). Chloride penetration was measured by the rapid chloride permeability test (RCPT)-ASTM C1202, 150-days ponding test and alternate wetting and drying test by cyclic loading with salt solution and oven drying, and the results by the three test methods were compared. This paper discussed the effects of mineral admixtures and w/b on the concrete chloride permeability. Blending concrete with blast furnace slag, fly ash or silica fume was beneficial with regard to the resistance against chloride ion penetration. Concrete specimens with lower w/b showed lower chloride permeability.

Chlorogenic acid (CGA) is one of the most abundant polyphenol compounds in human diet. It is also an active component in traditional Chinese medicines which are used to treat various diseases. In this study, fluorescence spectroscopy in combination with UV-Vis absorption spectroscopy was employed to investigate the specific binding of CGA to human serum albumin (HSA) under the physiological conditions. In the mechanism discussion, it was proved that the fluorescence quenching of HSA by CGA is a result of the formation of CGA-HSA complex. Binding parameters calculating from Stern-Volmer method and Scatchard method showed that CGA bind to HSA with the binding affinities of the order 10(4) l mol(-1). The thermodynamic parameters studies revealed that the binding was characterized by negative enthalpy and positive entropy changes and the electrostatic interactions play a major role for CGA-HSA association. Site marker competitive displacement experiments demonstrated that CGA specific bind to site I (subdomain IIA) of HSA. The binding distance r (3.10 nm) between donor (Trp-214) and acceptor (CGA) was obtained according to fluorescence resonance energy transfer. Furthermore, the effect of metal ions on CGA-HSA system was studied.

The interaction of caffeine with bovine serum albumin (BSA) under physiological condition was investigated by fluorescence, UV-vis absorption and circular dichroism (CD) spectroscopy. Fluorescence data revealed that the fluorescence quenching of BSA by caffeine was a result of the formation of BSA-caffeine complex. The binding constants Ka at different temperatures and corresponding thermodynamic parameters ΔH, ΔG and ΔS were calculated. The spectroscopic measurements and the thermodynamic parameters suggested that van der Waals interaction and hydrogen bonds were the predominant intermolecular forces to stabilize the complex. The conformational change of BSA induced by caffeine has been analyzed by means of CD and synchronous fluorescence spectroscopy. Furthermore, it is observed from the probe of competitive experiments that the binding location of caffeine with BSA could be the same as warfarin binding site I of BSA, which was also revealed by fluorescence anisotropy.

Naringenin, a flavanone compound highly enriched in grapefruits, has been identified as a possible inhibitor of cell proliferation; and thus has the potential to act as an antitumorigenic agent. In this study, the binding of naringenin to bovine serum albumin (BSA) was studied at the physiological conditions (pH=7.40) by fluorescence and UV–vis spectroscopy. Naringenin strongly quenches the intrinsic fluorescence of BSA, and a decrease in the fluorescence quenching constant was observed together with an increase in temperature, which indicates that the fluorescence quenching of BSA by naringenin is a result of the formation of naringenin–BSA complex. Binding parameters calculating from Stern-Volmer method and Scatchard method showed that naringenin bind to BSA with the binding affinities of the order 104 L mol−1. Thermodynamic parameters such as ΔG, ΔH and ΔS, were calculated at different temperatures, showing that electrostatic interactions were mostly responsible for the binding of naringenin to BSA. Site marker competitive displacement experiments demonstrating that naringenin bind with high affinity to site I (subdomain IIA) of BSA. Furthermore, the effect of metal ions to naringenin–BSA system was studied, and the specific binding distance r (3.30 nm) between donor (Trp-212) and acceptor (naringenin) was obtained according to fluorescence resonance energy transfer (FRET).

This paper proposes an attack algorithm for digital image watermarking based on independent component analysis (ICA). The paper gives a briefly introduction about ICA algorithm, and expatiates on the attack algorithm which we proposed. The algorithm uses an auxiliary image to remove the watermark signal from the host image based on blind signal separation technology. The paper also does some experiment to attack the watermark algorithm proposed by I J. Cox. The results show that this attack algorithm not only removes most of the digital watermark information, but also has little effect on the image’s peak signal to noise ratio. The paper also discusses the attack algorithm for different watermark signals and different auxiliary images; the effect of this attack algorithm is feasible.

Ofloxacin is an antibacterial compound that belongs to the fluoroquinolone family. In this paper, the interaction between ofloxacin and bovine serum albumin (BSA) was investigated by fluorescence spectroscopy and UV-Vis absorbtion spectroscopy under approximately the human physiological conditions. The thermodynamic parameters were calculated according to the dependence of enthalpy change on the temperature as follows: ΔH has a small negative value (−9.96 kJ⋅mol−1), whereas ΔS has a positive value (54.77 J⋅mol−1⋅K−1). In this work, it was proved that the fluorescence quenching of BSA by ofloxacin is a result of the formation of an ofloxacin–BSA complex. Binding studies concerning the number of binding sites (n=1.14) and apparent binding constant were performed by Scatchard’s procedure. The binding distance r between donor (BSA) and acceptor (ofloxacin) was obtained according to the fluorescence resonance energy transfer (FRET) method.

Heteropolyoxometalate complexes have been widely applied in many fields. In this paper, the interaction between a series of novel rare earth molybdotungstosilicate heteropolyoxometalates, K(10)H(3)[Ln(SiMo(6)W(5)O(39))(2)].xH(2)O (abbr. LnW(5), Ln = Pr (x = 30), Gd (x = 29), Dy (x = 28), and Yb (x = 31)), and bovine serum albumin (BSA) was investigated by spectroscopic approach under the physiological conditions. In the mechanism discussion, it was proved that the fluorescence quenching of BSA by LnW(5) is a result of the formation of LnW(5)-BSA complex. Fluorescence quenching constants were determined using the Stern-Volmer equation to provide a measure of the binding affinity between LnW(5) and BSA. The binding affinity ranked in the order GdW(5) > DyW(5) > PrW(5) > YbW(5). The results of thermodynamic parameters DeltaG, DeltaH, and DeltaS at different temperatures indicate that van der Waals interactions and hydrogen bonds play a major role for LnW(5)-BSA association. Furthermore, the distance r between donor (BSA) and acceptor (LnW(5)) was obtained according to fluorescence resonance energy transfer.