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ATF6 has two isoforms, ATF6α and ATF6β, which are ubiquitously expressed type II transmembrane glycoproteins in the endoplasmic reticulum (ER). While the regulatory mechanisms and transcriptional roles of ATF6α in response to ER stress have been well-studied, those of its paralogue ATF6β are less understood. Moreover, there is no specific cell-based reporter assay to monitor ATF6β activation. Here, we developed a new cell-based reporter system that can monitor activation of endogenous ATF6β. This system expresses a chimeric protein containing a synthetic transcription factor followed by the transmembrane domain and C-terminal luminal domain of ATF6β. Under ER stress conditions, the chimeric protein was cleaved by regulated intramembrane proteolysis (RIP) to liberate the N-terminal synthetic transcription factor, which induced luciferase expression in the HeLa Luciferase Reporter cell line. This new stable reporter cell line will be an innovative tool to investigate RIP of ATF6β.

Although the spread of plasmid-mediated antibiotic-resistant bacteria is a public health concern, food contamination with plasmid-mediated antibiotic-resistant Escherichia coli has not been well investigated in Vietnam. The aim of this study was to describe the prevalence of colistin-resistant, carbapenem-resistant and endemic blaCTX−M in extended-spectrum β-lactamase (ESBL)-producing E. coli isolates. Colistin- and carbapenem-resistant ESBL-producing E. coli were isolated from chickens in Vietnam and Japan. The results showed that 52% and 93% of Vietnamese chicken was isolated with colistin-resistant and AmpC/ESBL-producing E. coli, respectively, while 52.7% of Japanese chickens were isolated with AmpC/ESBL-producing E. coli. Carbapenem-resistant E. coli has not been isolated in Vietnam or Japan. Genotyping revealed that colistin-resistant E. coli harboured mcr-1, and most of the AmpC/ESBL-related genes were blaCTX−M−55 and blaCTX−M−65 together with blaTEM in Vietnamese chickens, and blaCMY−2 in Japanese chickens. Multidrug resistance analysis showed that ESBL-producing E. coli isolates were more resistant to quinolones, streptomycin, and chloramphenicol compared with colistin-resistant E. coli isolates from Vietnam, suggesting selection in ESBL-producing E. coli for multiple antibiotic resistance genes. In conclusion, colistin-resistant E. coli was detected in about half of the chicken meat samples, the majority of which were found to harbour mcr-1. The high prevalence of ESBL-producing E. coli has remained constant across the last five years, and the predominant blaCTX−M for ESBL-producing E. coli was found to be blaCTX−M−55 or blaCTX−M−65, with the coexistence of blaTEM in Vietnam. Our results can be implemented in monitoring systems to combat the development of antimicrobial resistance.

Bacterial blight is one of the most devastating rice diseases that cause huge economic loss worldwide. The cause of rice blight is Gram negative bacteria Xanthomonas oryzae pv. oryzae (X. oryzae pv. Oryzae). Since both silver nanoparticles and chitosan have antibacterial, antifungal and growth-stimulating effect, this work has focused on synthesizing chitosan stabilized silver nanoparticles (AgCSs) with small sizes and in vitro evaluating antibacterial activity against X. oryzae pv. oryzae bacteria. AgCSs were chemically synthesized by reducing silver nitrate by borohydride sodium in the presence of chitosan with optimization of the concentration of the reactants. AgCSs were characterized by UV/vis absorption spectra, field emission scanning electronic microscopy (FESEM), ImageJ software, zeta potential measurement, Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction. AgCSs have spherical configuration and narrow size distributions with different average sizes from 15 nm to 25 nm depending on the initial concentration of silver nitrate. All AgCSs colloidal systems were stable and exhibited no tendency for coagulation more than 5 months. It was the first time that chitosan-stabilized silver nanoparticles were assessed the in vitro antibacterial activity against bacterial blight VXO_281 strain. The disc diffusion method demonstrated that the smallest size silver nanoparticles (AgCS1) showed high antibacterial effect against the X. oryzae pv. oryzae VXO_281 strain with a concentration of more than 5 µg/mL and the inhibition zone was dose-dependent. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of AgCS1 against X. oryzae pv. oryzae VXO_281 were 2.5 µg/mL and 20 µg/mL, respectively.

Aim Early life stress can induce epigenetic changes through genetic and environmental interactions and is a risk factor for depression. Brain-derived neurotrophic factor (BDNF) has been implicated in the pathophysiology of depression and antidepressant drug action. We investigated epigenetic changes at the BDNF exon I promoter in the hippocampus of adult rats subjected to maternal separation (MS) during early life and treated with an antidepressant drug as adults. Methods Rat pups were subjected to MS from postnatal day 1 to 21 and received chronic escitalopram (ESC) as adults. We assessed the effects of MS and ESC on BDNF exon I and DNA methyltransferases (DNMTs) mRNA levels (quantitative reverse-transcription polymerase chain reaction [qRT-PCR]), acetylated histone H3 and MeCP2 binding to the BDNF promoter I (chromatin immunoprecipitation followed by real-time PCR), and BDNF protein levels (enzyme-linked immunosorbent assay). Results The levels of BDNF protein, exon I mRNA, histone H3 acetylation, and DNMT1 and DNMT3a mRNA were altered in the MS group compared with the control group. Significant decreases were observed in the BDNF protein, exon I mRNA, and histone H3 acetylation levels and significant increases in DNMT1 and DNMT3a mRNA levels. The comparison between the MS + ESC and MS groups revealed significant increases in BDNF protein, exon I mRNA, and histone H3 acetylation levels and significant decreases in MeCP2 and DNMT1 and DNMT3a mRNA levels. Conclusion These findings indicate that MS induced epigenetic changes at the BDNF exon I promoter and these changes were prevented by antidepressant drug treatment during adulthood.

The group II metabotropic glutamate 2/3 (mGlu2/3) receptor antagonist LY341495 produces antidepressant-like effects by acting on mammalian target of rapamycin complex 1 (mTORC1) signaling and α-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptors in rodent. We investigated whether LY341495 affects neuroplasticity via these mechanisms in rat primary hippocampal cultures under conditions of dexamethasone (DEX)-induced neurotoxicity. Ketamine was used for comparison. Hippocampal cultures were treated with LY341495 under conditions of DEX-induced toxicity. Changes in mTORC1-mediated proteins were determined by Western blotting analyses. Changes in dendritic outgrowth and spine density were evaluated via immunostaining. LY341495 significantly prevented DEX-induced decreases in the levels of mTORC1, 4E-BP1, and p70S6K phosphorylation as well as the levels of the synaptic proteins. These effects were blocked by pretreatment with the AMPA receptor inhibitor 2,3-dihydroxy-6-nitro-7sulfamoyl-benzo(f)quinoxaline (NBQX) and the mTORC1 inhibitor rapamycin. LY341495 significantly attenuated DEX-induced decreases in dendritic outgrowth and spine density. Pretreatment with rapamycin and NBQX blocked these effects of LY341495. Further analyses indicted that induction of BDNF expression produced by LY341495 was blocked by pretreatment with NBQX and rapamycin. LY341495 has neuroplastic effects by acting on AMPA receptor-mTORC1 signaling under neurotoxic conditions. Therefore, activation of AMPA receptor and mTORC1 signaling, which enhance neuroplasticity, may be novel targets for new antidepressants.

Early life stress can induce epigenetic changes through genetic and environmental interactions and is a risk factor for depression. Brain-derived neurotrophic factor (BDNF) has been implicated in the pathophysiology of depression and antidepressant drug action. We investigated epigenetic changes at the BDNF exon I promoter in the hippocampus of adult rats subjected to maternal separation (MS) during early life and treated with an antidepressant drug as adults.Rat pups were subjected to MS from postnatal day 1 to 21 and received chronic escitalopram (ESC) as adults. We assessed the effects of MS and ESC on BDNF exon I and DNA methyltransferases (DNMT) mRNA levels (quantitative reverse-transcription polymerase chain reaction), acetylated histone H3, and MeCP2 binding to the BDNF promoter I (chromatin immunoprecipitation followed by real-time polymerase chain reaction), and BDNF protein levels (enzyme-linked immunosorbent assay).The levels of BDNF protein, exon I mRNA, histone H3 acetylation, and DNMT1 and DNMT3a mRNA were altered in the MS group compared with the control group. Significant decreases were observed in the BDNF protein, exon I mRNA, and histone H3 acetylation levels and there were significant increases in DNMT1 and DNMT3a mRNA levels. The comparison between the MS + ESC and MS groups revealed significant increases in BDNF protein, exon I mRNA, and histone H3 acetylation levels and significant decreases in MeCP2 and DNMT1 and DNMT3a mRNA levels.These findings indicate that MS induced epigenetic changes at the BDNF exon I promoter and these changes were prevented by antidepressant drug treatment during adulthood.

This review focuses on methods of designing photocontrolled proteins and nucleic acids. Data on preparation and modification of proteins and nucleic acids with azobenzene derivatives are summarized. Examples of using photoswitchable proteins, their substrates, inhibitors and ligands containing azobenzene, as well as azobenzene derivatives of nucleic acids, for design of nanomachines are considered. The bibliography includes 122 references.

Acute encephalitis syndrome (AES) is associated with high morbidity and mortality, and affects both children and adults. The main etiologic agent is Japanese encephalitis virus (JEV); however, there are also reports of Dengue virus (DENV) encephalitis. The objectives of this study were to determine the proportion of patients with encephalitis due to JEV during the 2014 outbreak in Son La Province in Vietnam and to explore the association of DENV in non-JEV viral encephalitis cases. Of 90 patients, 6 (6.7%) were positive for anti-JEV immunoglobulin M (IgM), 5 (5.6%) were positive for anti-DENV IgM, 30 (33.3%) were positive for both anti-JEV and anti-DENV IgM, and 56 (62.2%) were positive for flavivirus immunoglobulin G (IgG). In 5 patients with AES, who had positive anti-DENV IgM results in at least one of the paired serum samples, DENV was confirmed by neutralization testing. The incidence of JEV infection was high. There is still a need to maintain and strengthen the national JEV immunization program. This noticeable occurrence of DENV infection was not reported in Son La Province in 2013?2014. Our data suggested that in addition to JEV, DENV was also a causative agent of AES in 2014 in Son La Province, and this finding also confirmed the local occurrence of DENV infection., Japanese Journal of Infectious Diseases, 70(4), pp.357-361; 2017

For many applications it would be desirable to be able to control the activity of proteins by using an external signal. In the present study, we have explored the possibility of modulating the activity of a restriction enzyme with light. By cross-linking two suitably located cysteine residues with a bifunctional azobenzene derivative, which can adopt a cis - or trans -configuration when illuminated by UV or blue light, respectively, enzymatic activity can be controlled in a reversible manner. To determine which residues when cross-linked show the largest “photoswitch effect,” i.e., difference in activity when illuminated with UV vs. blue light, > 30 variants of a single-chain version of the restriction endonuclease PvuII were produced, modified with azobenzene, and tested for DNA cleavage activity. In general, introducing single cross-links in the enzyme leads to only small effects, whereas with multiple cross-links and additional mutations larger effects are observed. Some of the modified variants, which carry the cross-links close to the catalytic center, can be modulated in their DNA cleavage activity by a factor of up to 16 by illumination with UV (azobenzene in cis ) and blue light (azobenzene in trans ), respectively. The change in activity is achieved in seconds, is fully reversible, and, in the case analyzed, is due to a change in V max rather than K m .

Derivatives of azobenzene which contained a maleimide group in one of the benzene rings (for binding to a protein cysteine residue) and maleimide, hydroxyl, or carboxyl substitutes in another benzene ring were synthesized. The reactivity of these compounds towards a cysteine residue of a protein and their optical properties in a free form and after their attachment to the mutant forms of the SsoII restriction endonuclease were studied.

We developed a metal ion chelate-assisted ligation for SNP detection by microarray. An oligonucleotide probe was separated into two 9-10-mers bearing iminodiacetic residues at the gap point. Duplex formation with the DNA target was possible only if nickel ions were added, but a nucleotide substitution opposite the gap point prevented duplex formation. Here we demonstrate the application of this approach for SNP detection (A1298C) within the 5,10-methylenetetrahydrofolate reductase gene on a microarray.

The adsorption of a basic dye (Methylene Blue; MB) and an acidic dye (Acid Orange; AO) has been studied on three activated carbons (ACs; FAS, SKD, and BAU) significantly differing in their porous structures and surface concentrations of ion-exchange groups and on graphitic thermal carbon black (GTCB). The effective specific surface area of FAS, SKD, and BAU determined by dye adsorption is, respectively, 60, 50, and 40% of the BET nitrogen adsorption surface area. The MB uptake on ACs and GTCB increases with rising pH, while the AO uptake decreases. Addition of an electrolyte (0.3 M NaCl) virtually does not effect the adsorption of dyes on ACs and GTCB. It is suggested that hydrophobic interactions, and not ionic ones, are the major contributors to the adsorption of dyes on ACs.

108 Oligonucleotides, modified ones including, are widely used in different fields of molecular biology. They are used as primers for sequencing and amplifying DNA and determining the DNA primary structure by the hybridization method and are promising therapeutic agents [1]. One of the fields of application of modified oligonucleotides is the preparation of their conjugates with various compounds such as peptides, oligosaccharides, and dyes for studying the behavior of nucleic acids in vitro or in vivo [2]. The attachment of dyes or electrochemically active compounds to oligonucleotides provides an opportunity to use these derivatives for the design of systems of DNA detection by the hybridization method [3]. The presence of marker groups considerably increases the sensitivity of DNA determination. The conjugates of oligonucleotides with peptides, carbohydrates, and lipophilic compounds often better penetrate through cell membranes as compared with natural nucleic acids, which can be used in antisense biotechnology and RNA interference [4]. At present, oligonucleotides bearing aldehyde groups are widely used for preparing different conjugates with fluorophores, peptides, and proteins [5].

With the aim to use a "flat film-like shape" excitation source in the opto-biomedical analysis system (OBMAS), a deep-blue organic light emitting diodes (OLED) with 240 mm2 in size and an emission wavelength of 455 nm were fabricated by vacuum evaporation of low-molecular-weight polymers. In the devices N, N-Bis(naphthalen-1-yl)-. N, N-bis(phenyl) benzidine (NPB) was used for hole transport layer (HTL), 2-methyl-9, 10-bis(naphthalene-2-yl)anthracene (MADN) -- for emitting layer (EML) and tris(8-hydroxyquinolinato)aluminum(III) (Alq3) -- for electron transport layer (ETL). The output power, the luminous efficiency, the peak wavelength and the full width at half-maximum (FWHM) of the deep-blue OLED were 1.5 mW, 1.0 cd/A, 455 nm and 100 nm, respectively, at a forward current of 30 mA. Under excitation of this excitation source, the photo luminance of the CdSe-QDs attached with listeria monocytogenes bacteria exhibit clear orange colour light. The image of the luminance was detected by a 1.3 Mpx sensitive web cam. This can be used in the biomedical analysis by using an optic microscope acting like an opto-biomedical microanalysis system (OBMAS). With use of the OBMAS one can qualitatively detect the presence of bacteria attached to the QDs through specific antibodies.

A novel method for regulating the activity of homodimeric proteins--"molecular gate" approach--was proposed and its usefulness illustrated for the type II restriction endonuclease SsoII (R.SsoII) as a model. The "molecular gate" approach is based on the modification of R.SsoII with azobenzene derivatives, which allows regulating DNA binding and cleavage via illumination with light. R.SsoII variants with single cysteine residues introduced at selected positions were obtained and modified with maleimidoazobenzene derivatives. A twofold change in the enzymatic activity after illumination with light of wavelengths of 365 and 470 nm, respectively, was demonstrated when one or two molecules of azobenzene derivatives were attached to the R.SsoII at the entrance of or within the DNA-binding site.

This study was conducted to examine total phenolic contents of Sorghum bicolor (L.) Moench shoot extracts in different cultivars andunder different extraction methods by HPLC analysis. In the first experiment, five cultivars of sorghum (Milyang-1ho, Milyang-5ho, Donganme, Hwanggumchal and Nampungchal) were extracted by soaking in distilled water for 24h at room temperature and boiling for 2 h, followed by filtering and evaporating. For the second experiment, focus was given to a known allelochemical, the phenolic compound 4-hydroxybenzoic acid. Hwanggumchal, the cultivar with the highest 4-hydroxybenzoic acid content from the first experiment, was chosen for optimizing phenolic compound extraction under different conditions such as solvent (distilled water or ethanol), temperature (4o, 25o and 40°C), and time (24, 48 and 72 h). An HPLC system was used to quantitatively determine total phenolic contents of extracts. Results showed that, between the five cultivars, Donganme had the highest total phenolic compounds (402.6 mg/l), while Hwanggumchal had the highest amount of 4-hydroxybenzoic acid (96.0 mg/l). In the second experiment, the highest amount of total phenolic compounds was obtained when the sorghum samples were extracted in ethanol by soaking for 72 h at 40°C, while the lowest amount was obtained by soaking 72 h at 4°C in distilled water. The study and application of the allelopathy phenomenon in weed control is essential for the protection of the environment. If adopted successfully, it could lead to significant accomplishments for sustainable agriculture.

The agricultural industry has tried to develop effective herbicides, especially biological herbicides, with less impact on our agricultural environment. Recently, allelopathy has emerged as a potential alternative to chemical herbicides for weed management. Allelopathy is defined as "any direct or indirect, harmful or beneficial effects of one plant on another through the production of chemical compounds that are released into the environment."Sorghum bicolor (L.) Moench, a species that originates from Africa and is widely cultivated in both tropical and sub-tropical regions, is considered as a rich source of allelochemicals with biological weed control ability. Chemical constituents of sorghum include tannins, phenolic acids, anthocyanins, phytosterols and policosanols. Investigations on underground parts of sorghum indicate that sorgoleone is in charge of the weed control activity, while phenolic compounds play a vital role in its herbicidal activity on aerial parts of weeds. This review aims at providing up-to-date and comprehensive information about allelopathy in sorghum and further application of sorghum extract in weed control.