Field evaluation on the synergistic attractiveness of 2‐(1‐undecyloxy)‐1‐ethanol and ipsenol to Monochamus saltuarius

To develop an optimal attractant for Monochamus saltuarius (Gebler) (Coleoptera: Cerambycidae), the synergistic effects of a few potential attractants (ethanol and α‐pinene as host‐plant volatiles, and ipsenol and ipsdienol as bark beetle pheromones) were tested in a pine forest combined with 2‐(1‐undecyloxy)‐1‐ethanol (monochamol), the aggregation pheromone of Monochamus species, for two consecutive years, 2014 and 2015. Total number of catches was 65 and 33 in 2014 and 2015, respectively. Ethanol or ethanol + monochamol (a base blend) were not attractive to M. saltuarius with no difference from the control. Addition of α‐pinene and ipsdienol to the base blend did not significantly increase catches. However, ipsenol was significantly synergistic to the base blend in attracting M. saltuarius in 2014, and the blend (ipsenol + base blend) attracted meaningfully higher numbers of M. saltuarius in 2015. Our study illustrates the potential for monochamol and ipsenol baits for monitoring and trapping of M. saltuarius in the field.     

The evaluation of acute toxicity,antimicrobial activity of 1‐phenyl‐5‐p‐tolyl‐1H‐1, 2, 3‐triazole,and binding to human serum albumin

1‐Phenyl‐5‐p‐tolyl‐1H‐1, 2, 3‐triazole (PPTA) was a synthesized compound. The result of acute toxicities to mice of PPTA by intragastric administration indicated that PPTA did not produce any significant acute toxic effect on Kunming strain mice. It exhibited the various potent inhibitory activities against two kinds of bananas pathogenic bacteria, black sigatoka and freckle, when compared with that of control drugs and the inhibitory rates were up to 64.14% and 43.46%, respectively, with the same concentration of 7.06 mM. The interaction of PPTA with human serum albumin (HSA) was studied using fluorescence polarization, absorption spectra, 3D fluorescence, and synchronous spectra in combination with quantum chemistry and molecular modeling. Multiple modes of interaction between PPTA and HSA were suggested to stabilize the PPTA–HSA complex, based on thermodynamic data and molecular modeling. Binding of PPTA to HSA induced perturbation in the microenvironment around HSA as well as secondary structural changes in the protein.     

Synthesis and Biological Evaluation of Novel 1‐(4‐(Hydroxy(1‐oxo‐1,3‐dihydro‐2H‐inden‐2‐ylidene)methyl)phenyl)‐3‐phenylurea Derivatives

A series of novel phenylurea containing 2‐benzoylindan‐1‐one derivatives 3a  –  3j were synthesized from the reaction of phenylurea‐substituted acetophenones 1a  –  1j with phthalaldehyde 2 under mild reaction conditions in good yields. All synthesized compounds were characterized by spectroscopic methods. The obtained compounds ( 3a  –  3j ) were evaluated for anticancer activity against HeLa and C6 cell lines. Antiproliferative activity was determined by the BrdU proliferation ELISA assay, 3f and 3g were found to be most active compounds. The compounds were also screened for antimicrobial activity and all compounds showed remarkable activity against used microorganisms.     

Asymmetric Allylation of α‐Ketoester‐Derived N‐Benzoylhydrazones Promoted by Chiral Sulfoxides/N‐Oxides Lewis Bases: Highly Enantioselective Synthesis of Quaternary α‐Substituted α‐Allyl‐α‐Amino Acids

Chiral sulfoxides/N‐oxides (R)‐ 1 and (R,R)‐ 2 are effective chiral promoters in the enantioselective allylation of α‐keto ester N‐benzoylhydrazone derivatives 3a , 3b , 3c , 3d , 3e , 3f , 3g to generate the corresponding N‐benzoylhydrazine derivatives 4a , 4b , 4c , 4d , 4e , 4f , 4g , with enantiomeric excesses as high as 98%. Representative hydrazine derivatives 4a , 4b were subsequently treated with SmI₂, and the resulting amino esters 5a , 5b with LiOH to obtain quaternary α‐substituted α‐allyl α‐amino acids 6a , 6b , whose absolute configuration was assigned as (S), with fundament on chemical correlation and electronic circular dichroism (ECD) data. Chirality 25:529–540, 2013. © 2013 Wiley Periodicals, Inc.     

Spectrofluorimetric determination of aluminium using 2‐hydroxy‐1‐naphthylidene‐(8‐aminoquinoline)

A sensitive and selective spectrofluorimetric method has been developed for the rapid determination of aluminium. This method is based on the complex formation between aluminium and 2‐hydroxy‐1‐naphthylidene‐(8‐aminoquinoline) (HNAQ). The optimum conditions for the complex formation were a metal‐to‐ligand (M : L) stoichiometric ratio of 1:1, a pH of 5.5 and a 0.20 m acetate buffer. The fluorescence of the complex was monitored at an emission wavelength of 502 nm with excitation at 438 nm. Under these conditions, linear calibration curves were obtained in the ranges 0.05–1 and 1–5 ppm. The detection limit was 3.4 ppb for the former and 13.5 ppb for the latter. The maximum relative standard deviation of the method for an aluminium standard of 200 ppb was 1.5% (n = 5). This method was successfully applied for the determination of aluminium in drinking water, pharmaceutical antacid tablets and suspension samples. Copyright © 2010 John Wiley & Sons, Ltd.     

Thrombin stimulates RPE cell motility by PKC‐ζ‐ and NF‐κB‐dependent gene expression of MCP‐1 and CINC‐1/GRO chemokines

Retinal pigment epithelial cells (RPE) are the major cell type involved in the pathogenesis of proliferative vitreoretinopathy (PVR), which involves the epithelial‐mesenchymal transition, proliferation, and directional migration of transformed RPE cells to the vitreous upon RPE exposure to serum components, thrombin among them. Although the aqueous humor and vitreous of PVR patients contain high levels of chemokines, their possible involvement in PVR development has not been explored. We here analyzed the effect of thrombin on chemokine gene expression and its correlation with RPE cell migration using rat RPE cells in culture as a model system. We demonstrated that thrombin induces RPE cell migration through the dose‐dependent stimulation of MCP1 and GRO expression/release, and the autocrine activation of CXCR‐2 and CCR‐2 chemokine receptors. Whereas inhibition of CXCR2 by Sb‐225002 and of CCR2 by Rs‐504393 partially prevented hirudin‐sensitive cell migration, the joint inhibition of these receptors abolished thrombin effect, suggesting the contribution of distinct but coincident mechanisms. Thrombin effects were not modified by Ro‐32‐0432 inhibition of conventional/novel PKC isoenzymes or by the MAPkinase pathway inhibitor U0126. MCP1 and GRO expression/secretion, and cell migration were completely prevented by the inhibitory PKC‐ζ pseudosubstrate and by the nuclear factor‐kappa B (NF‐κB) inhibitor BAY11‐7082, but not by wortmannin inhibition of PI3K. Results show that signaling pathways leading to RPE cell migration differ from the MEK–ERK–PI3K‐mediated promotion RPE of cell proliferation, both of which concur at the activation of PKC‐ζ. J. Cell. Biochem. © 2010 Wiley‐Liss, Inc.     

Enzyme Kinetics of an Alternative Splicing Isoform of Mitochondrial 8‐Oxoguanine DNA Glycosylase,OGG1‐1b,and Compared with the Nuclear OGG1‐1a

Eight alternatively spliced isoforms of human 8‐oxoguanine DNA glycosylase (OGG1) (OGG1‐1a to ‐1c and ‐2a to ‐2e) are registered in the National Center for Biotechnology Information. OGG1(s) in mitochondria have not yet been fully characterized biochemically. In this study, we purified mitochondrial recombinant OGG1‐1b protein and compared its activity with nuclear OGG1‐1a protein. The reaction rate constant (k_g) of the 7,8‐dihydro‐8‐oxoguanine (8‐oxoG) glycosylase activity of OGG1‐1b was 8‐oxoG:C >> 8‐oxoG:T >> 8‐oxoG:G > 8‐oxoG:A (7.96, 0.805, 0.070, and 0.015 min^?1, respectively) and that of the N‐glycosylase/DNA lyase activity (k_gl) of OGG1‐1b was 8‐oxoG:C > 8‐oxoG:T ?8‐oxoG:G >> 8‐oxoG:A (0.286, 0.079, 0.040, and negligible min^?1, respectively). These reaction rate constants were similar to those of OGG1‐1a except for k_gl against 8‐oxoG:A. APEX nuclease 1 was required to promote DNA strand breakage by OGG1‐1b. These results suggest that OGG1‐1b is associated with 8‐oxoG cleavage in human mitochondria and that the mechanism of this repair is similar to that of nuclear OGG1‐1a.     

5α‐Androst‐16‐en‐3α‐ol β‐D‐Glucuronide,Precursor of 5α‐Androst‐16‐en‐3α‐ol in Human Sweat

5α‐Androst‐16‐en‐3α‐ol (α‐androstenol) is an important contributor to human axilla sweat odor. It is assumed that α‐andostenol is excreted from the apocrine glands via a H₂O‐soluble conjugate, and this precursor was formally characterized in this study for the first time in human sweat. The possible H₂O‐soluble precursors, sulfate and glucuronide derivatives, were synthesized as analytical standards, i.e., α‐androstenol, β‐androstenol sulfates, 5α‐androsta‐5,16‐dien‐3β‐ol (β‐androstadienol) sulfate, α‐androstenol β‐glucuronide, α‐androstenol α‐glucuronide, β‐androstadienol β‐glucuronide, and α‐androstenol β‐glucuronide furanose. The occurrence of α‐androstenol β‐glucuronide was established by ultra performance liquid chromatography (UPLC)/MS (heated electrospray ionization (HESI)) in negative‐ion mode in pooled human sweat, containing eccrine and apocrine secretions and collected from 25 female and 24 male underarms. Its concentration was of 79 ng/ml in female secretions and 241 ng/ml in male secretions. The release of α‐androstenol was observed after incubation of the sterile human sweat or α‐androstenol β‐glucuronide with a commercial glucuronidase enzyme, the urine‐isolated bacteria Streptococcus agalactiae, and the skin bacteria Staphylococcus warneri DSM 20316, Staphylococcus haemolyticus DSM 20263, and Propionibacterium acnes ATCC 6919, reported to have β‐glucuronidase activities. We demonstrated that if α‐ and β‐androstenols and androstadienol sulfates were present in human sweat, their concentrations would be too low to be considered as potential precursors of malodors; therefore, the H₂O‐soluble precursor of α‐androstenol in apocrine secretion should be a β‐glucuronide.     

Mutation in the gene encoding 1‐aminocyclopropane‐1‐carboxylate synthase 4 (CitACS4) led to andromonoecy in watermelon

Although it has been reported previously that ethylene plays a critical role in sex determination in cucurbit species, how the andromonoecy that carries both the male and hermaphroditic flowers is determined in watermelon is still unknown. Here we showed that the watermelon gene 1-aminocyclopropane-1-carboxylate synthase 4(Cit ACS4), expressed specifically in carpel primordia, determines the andromonoecy in watermelon. Among four single nucleotide polymorphism(SNPs) and one InDel identified in the coding region of Cit ACS4, the C364 W mutation located in the conserved box 6 was cosegregated with andromonoecy. Enzymatic analyses showed that the C364 W mutation caused a reduced activity in Cit ACS4. We believe that the reduced Cit ACS4 activity may hamper the programmed cell death in stamen primordia, leading to the formation of hermaphroditic flowers.     

Synthesis of 3‐Methylidene‐1‐tosyl‐2,3‐dihydroquinolin‐4(1H)‐ones as Potent Cytotoxic Agents

An efficient synthetic strategy to 3‐methylidene‐2,3‐dihydroquinolin‐4(1H)‐ones variously substituted in position 2 has been developed. The title compounds were synthesized in the reaction sequence involving reaction of diethyl methylphosphonate with methyl 2‐(tosylamino)benzoate, condensation of thus formed diethyl 2‐oxo‐2‐(2‐N‐tosylphenyl)ethylphosphonate with various aldehydes followed by successful application of the obtained 3‐(diethoxyphosphoryl)‐1,2‐dihydroquinolin‐4‐ols as Horner–Wadsworth–Emmons reagents for the olefination of formaldehyde. Also, enantioselective approach to the target compounds has been evaluated using 3‐dimenthoxyphosphoryl group as a chiral auxiliary. Single X‐ray crystal analysis of (2S)‐3‐(dimenthoxyphosphoryl)‐2‐phenyl‐1‐tosyldihydroquinolin‐4‐ol revealed the presence of strong resonance‐assisted hydrogen bond (RAHB). The obtained 3‐methylidene‐2,3‐dihydroquinolin‐4(1H)‐ones were then tested for their cytotoxic activity against two leukemia cell lines NALM‐6 and HL‐60 and a breast cancer MCF‐7 cell line. All compounds showed very high cytotoxic activity with the IC₅₀ values mostly below 1 μm in all three cancer cell lines. The selected analogs were also tested on human umbilical vein endothelial cells (HUVEC) and on human mammary gland/breast cells (MCF‐10A) to evaluate their influence on normal cells. Since one of the most serious problems in cancer chemotherapy is the development of drug resistance, the mRNA levels and activity of ABCB1 transporter considered to be the most important factor engaged in drug resistance, were evaluated in MCF‐7 cells treated with two selected analogs. Both compounds were strong ABCB1 transporter inhibitors that could prevent efflux of anticancer drugs from cancer cells.     

Drug‐binding energetics of human α‐1‐acid glycoprotein assessed by isothermal titration calorimetry and molecular docking simulations

This study utilizes sensitive, modern isothermal titration calorimetric methods to characterize the microscopic thermodynamic parameters that drive the binding of basic drugs to α‐1‐acid glycoprotein (AGP) and thereby rationalize the thermodynamic data in relation to docking models and crystallographic structures of the drug–AGP complexes. The binding of basic compounds from the tricyclic antidepressant series, together with miaserine, chlorpromazine, disopyramide and cimetidine, all displayed an exothermically driven binding interaction with AGP. The impact of protonation/deprotonation events, ionic strength, temperature and the individual selectivity of the A and F1*S AGP variants on drug‐binding thermodynamics was characterized. A correlation plot of the thermodynamic parameters for all of the test compounds revealed that an enthalpy–entropy compensation is in effect. The exothermic binding energetics of the test compounds were driven by a combination of favorable (negative) enthalpic (?Hº) and favorable (positive) entropic (?Sº) contributions to the Gibbs free energy (?Gº). Collectively, the data imply that the free energies that drive drug binding to AGP and its relationship to drug serum residency evolve from the complex interplay of enthalpic and entropic forces from interactions with explicit combinations of hydrophobic and polar side‐chain sub‐domains within the multi‐lobed AGP ligand binding cavity.Copyright © 2012 John Wiley & Sons, Ltd.     

Neuroprotective effects of 1‐O‐hexyl‐2,3,5‐trimethylhydroquinone on ischaemia/reperfusion‐induced neuronal injury by activating the Nrf2/HO‐1 pathway

1‐O‐Hexyl‐2,3,5‐trimethylhydroquinone (HTHQ), a lipophilic phenolic agent, has an antioxidant activity and reactive oxygen species (ROS) scavenging property. However, the role of HTHQ on cerebral ischaemic/reperfusion (I/R) injury and the underlying mechanisms remain poorly understood. In the present study, we demonstrated that HTHQ treatment ameliorated cerebral I/R injury in vivo, as demonstrated by the decreased infarct volume ration, neurological deficits, oxidative stress and neuronal apoptosis. HTHQ treatment increased the levels of nuclear factor erythroid 2–related factor 2 (Nrf2) and its downstream antioxidant protein, haeme oxygenase‐1 (HO‐1). In addition, HTHQ treatment decreases oxidative stress and neuronal apoptosis of PC12 cells following hypoxia and reperfusion (H/R) in vitro. Moreover, we provided evidence that PC12 cells were more vulnerable to H/R‐induced oxidative stress after si‐Nrf2 transfection, and the HTHQ‐mediated protection was lost in PC12 cells transfected with siNrf2. In conclusion, these results suggested that HTHQ possesses neuroprotective effects against oxidative stress and apoptosis after cerebral I/R injury via activation of the Nrf2/HO‐1 pathway.