A novel type of Brassica napus with higher stearic acid in seeds developed through genome editing of BnaSAD2 family.

KEY MESSAGE: Modifications of multiple copies of the BnaSAD2 gene family with genomic editing technology result in higher stearic acid content in the seed of polyploidy rapeseed. Solid fats from vegetable oils are widely used in food processing industry. Accumulating data showed that stearic acid is more favorite as the major composite among the saturate fatty acids in solid fats in considerations of its effects on human health. Rapeseed is the third largest oil crop worldwide, and has potential to be manipulated to produce higher saturated fatty acids as raw materials of solid fats. Toward that end, we identified four SAD2 gene family members in B. napus genome and established spatiotemporal expression pattern of the BnaSAD2 members. Genomic editing technology was applied to mutate all the copies of BnaSAD2 in this allopolyploid species and mutants at multiple alleles were generated and characterized to understand the effect of each BnaSAD2 member on blocking desaturation of stearic acid. Mutations occurred at BnaSAD2.A3 resulted in more dramatic changes of fatty acid profile than ones on BnaSAD2.C3, BnaSAD2.A5 and BnaSAD2.C4. The content of stearic acid in mutant seeds with single locus increased dramatically with a range of 3.1-8.2%. Furthermore, combination of different mutated alleles of BnaSAD2 resulted in more dramatic changes in fatty acid profiles and the double mutant at BnaSAD2.A3 and BnaSAD2.C3 showed the most dramatic phenotypic changes compared with its single mutants and other double mutants, leading to 11.1% of stearic acid in the seeds. Our results demonstrated that the members of BnaSAD2 have differentiated in their efficacy as a Δ9-Stearoyl-ACP-Desaturase and provided valuable rapeseed germplasm for breeding high stearic rapeseed oil.

The expression of IGFBP-5 in the reproductive axis and effect on the onset of puberty in female rats.

Insulin-like growth factor-binding protein-5 (IGFBP-5) has recently been shown to alter the reproductive capacity by regulating insulin-like growth factor (IGF) bioavailability or IGF-independent effects. The present study aimed to investigate the effect and mechanism of IGFBP-5 on the onset of puberty in female rats. Immunofluorescence and real-time quantitative PCR were used to determine the expression and location of IGFBP-5 mRNA and protein distribution in the infant's hypothalamus-pituitary-ovary (HPO) axis prepuberty, peripuberty, puberty and adult female rats. Prepubertal rats with IGFBP-5 intracerebroventricular (ICV) were injected to determine the puberty-related genes expression and the concentrations of reproductive hormones. Primary hypothalamic cells were treated with IGFBP-5 to determine the expression of puberty-related genes and the Akt and mTOR proteins. Results showed that Igfbp-5 mRNA and protein were present on the HPO axis. The addition of IGFBP-5 to primary hypothalamic cells inhibited the expression of Gnrh and Igf-1 mRNAs (P < 0.05) and increased the expression of AKT and mTOR protein (P < 0.01). IGFBP-5 ICV-injection delayed the onset of puberty, reduced Gnrh, Igf-1, and Fshß mRNAs, and decreased the concentrations of E2, P4, FSH,serum LH levels and the ovaries weight (P < 0.05). More corpus luteum and fewer primary follicles were found after IGFBP-5 injection (P < 0.05).

Isolation and characterization of a new bioactive isoflavone from Derris eriocarpa.

Derris eriocarpa How is an important medicinal plant, which is used as Zhuang ethnomedicine and Dai ethnomedicine to treat various diseases. One new compound, 3',4'-di-O-methylene-5-hydroxy-7-methoxy-6-isopentenyl isoflavone (1) and a known synthetic but new naturally occurring compound trans-3,4,5-trimethoxy-4'-isopentenyloxyl-stilbene (2), together with five known compounds, 5,7-dimethoxy-6-(3-methyl-2-butenyl)-4'-hydroxyl isoflavones (3), robustone (4), trans-3,4,5,4'-tetramethoxy-stilbene (5), robustic acid (6), and robustin (7) were isolated from the stem of D. eriocarpa. Spectroscopic analysis revealed the chemical structures of compounds 1-7.. Compounds 1 and 3 exhibited significant scavenging activities against 1,1-diphenyl-2-picrylhydrazyl radical and superoxide anions. Compounds 1-3 exhibited potent antiproliferative activity on Hela cells.

Determination for Enterobacter cloacae based on a europium ternary complex labeled DNA probe.

The fast detection and accurate diagnosis of the prevalent pathogenic bacteria is very important for the treatment of disease. Nowadays, fluorescence techniques are important tools for diagnosis. A two-probe tandem DNA hybridization assay was designed for the detection of Enterobacter cloacae based on time-resolved fluorescence. In this work, the authors synthesized a novel europium ternary complex Eu(TTA)(3)(5-NH(2)-phen) with intense luminescence, high fluorescence quantum yield and long lifetime before. We developed a method based on this europium complex for the specific detection of original extracted DNA from E. cloacae. In the hybridization assay format, the reporter probe was labeled with Eu(TTA)(3)(5-NH(2)-phen) on the 5'-terminus, and the capture probe capture probe was covalent immobilized on the surface of the glutaraldehyde treated glass slides. The original extracted DNA of samples was directly used without any DNA purification and amplification. The detection was conducted by monitoring the fluorescence intensity from the glass surface after DNA hybridization. The detection limit of the DNA was 5×10(-10) mol L(-1). The results of the present work proved that this new approach was easy to operate with high sensitivity and specificity. It could be conducted as a powerful tool for the detection of pathogen microorganisms in the environment.

A novel bifunctional europium chelate applied in quantitative determination of human immunoglobin G using time-resolved fluoroimmunoassay.

The authors demonstrate herein a novel time-resolved fluoroimmunoassay (TRFIA) protocol for quantification of human IgG with the new bifunctional chelate Eu(TTA)3(5-NH2-phen) (ETNP) labeling the goat anti-human IgG. The immunoassay was conducted by following the typical procedure for sandwich-type immunoreactions. Goat anti-human IgG was immobilized on aldehyde-modified glass slides. The human IgG analyte was first captured by the primary antibody and then sandwiched by a secondary antibody labeled with the chelate ETNP. The experimental procedure was simple to follow and gave desirable levels of sensitivity and low limits of detection. To the best of our knowledge, this is the first application of the new chelate, ETNP, in an immunoassay. In comparison to typical organic, fluorescent compounds and other lanthanide fluorescent chelates used in immunoassay, the detection sensitivity of our method using ETNP chelate in the solid phase was greatly improved and a concentration of human IgG about 5 µg/L could be detected under optimal conditions. The main result of this work shows that the new chelate ETNP can be applied as a powerful fluorescent labeling material for constructing ultrasensitive TRFIAs. The detection of human IgG, using ETNP as the chelate, is a model example of the effectiveness of this immunoassay. Many other types of antigen-antibody immunoassays should be possible using the protocol described herein.

Time-resolved fluorescence aptamer-based sandwich assay for thrombin detection.

In the present study, the authors report a novel sensitive method for the detection of thrombin using time-resolved fluorescence sensing platform based on two different thrombin aptamers. The thrombin 15-mer aptamer as a capture probe was covalently attached to the surface of glass slide, and the thrombin 29-mer aptamer was fluorescently labeled as a detection probe. A bifunctional europium complex was used as the fluorescent label. The introduction of thrombin triggers the two different thrombin aptamers and thrombin to form a sandwich structure. The fluorescence intensity is proportional to the thrombin concentration. The present sensing system could provide both a wide linear dynamic range and a low detection limit. The proposed sensing system also presented satisfactory specificity and selectivity. Results showed that thrombin was retained at the aptamer-modified glass surface while nonspecific proteins were removed by rinsing with buffer solution. This approach successfully showed the suitability of aptamers as low molecular weight receptors on glass slides for sensitive and specific protein detection.

Directed shift of vaginal flora after topical application of sucrose gel in a phase III clinical trial: a novel treatment for bacterial vaginosis.

BACKGROUND: Bacterial vaginosis (BV) is one of the most common infectious diseases among sexually active women and is associated with the increased acquisition of a variety of sexually transmitted diseases. This study aimed to compare the efficacy of a non-antibiotic sucrose gel against an antibiotic metronidazole gel for the treatment of BV. METHODS: A randomized, double-blinded, multi-center, parallel-group, placebo-controlled phase III clinical trial was conducted at eight hospitals in China. A total of 560 subjects with clinically diagnosed BV were randomly assigned into three groups for vaginally receiving sucrose, metronidazole, and placebo gels, respectively, twice daily for five consecutive days. The efficacy of therapeutic cure, defined as an achievement of both microbiologic cure (a Nugent score of 3 or less) and clinical cure (a resolution of the clinical findings from the baseline visit), was evaluated at the 1st and 2nd test-of-cure (TOC) visits at 7-10 and 21-35 days after the start of treatment, respectively. RESULTS: Therapeutic cure rates for sucrose, metronidazole, and placebo gel groups were 83.13%, 71.30% and 0.92%, at the 1st TOC, and 61.04%, 66.67% and 7.34%, at the 2nd TOC, respectively. While there was no significant difference between the sucrose and metronidazole gel groups at the 2nd TOC (P = 0.305), and sucrose gel was more effective than metronidazole gel at the 1st TOC (P = 0.009). CONCLUSION: These findings suggest that sucrose gel restores normal vaginal flora more rapidly than metronidazole gel and can be used as a novel treatment for BV.

A novel bifunctional europium complex as a potential fluorescent label for DNA detection.

A bifunctional europium complex of Eu(TTA)(3)(5-NH(2)-phen) using 2-thenoyltrifluoroacetonate (TTA) and 5-amino-1,10-phenanthroline (5-NH(2)-phen) as ligand reagents was applied in DNA detection assays for the first time. The complex has a long fluorescence lifetime, high fluorescence quantum yield, and is easy to label oligonucleotides for time-resolved fluorescence bioanalysis. A two-probe tandem DNA hybridization assay including capture DNA(1), probe DNA(2), and target DNA(3) was employed to detect microbial pathogens. The DNA sequences in the assay were designed using software Primer Premier 5.0 based on published specific nucleotide sequences of Staphylococcus aureus and Escherichia coli. 3'-Amino-modified capture DNA(1) was covalently immobilized on the common glass slide surface and the 5'-amino-modified probe DNA(2) was combined with the functionalized Eu(TTA)(3)(5-NH(2)-phen) via glutaraldehyde. The detection was done by monitoring the fluorescence intensity from the glass surface after the hybridization reaction with complementary target DNA(3). The optimal concentration of capture DNA(1) of 1.0 x 10(-6) mol l(-1) dropped onto the glass slides and optimal hybridization temperatures of 48 degrees C and 39 degrees C respectively for Staphylococcus aureus and Escherichia coli were obtained. The proposed DNA detection system showed higher sensitivity than such a complex doped nanoparticle-based detection system in our previous study for the better uniformity and dispersity of monomolecular labels. The sensing system presented a short hybridization time of 2 h, satisfactory stability, and high selectivity. The results demonstrate that this complex might be a potentially excellent dye in area of biochemical analysis.

Sensitive and simple detection of Escherichia coli strain based on time-resolved fluorescence DNA hybridization assay.

A two-probe tandem DNA hybridization assay based on time-resolved fluorescence was employed to detect Escherichia coli strain. The amino modified capture probe was covalently immobilized on the common glass slide surface. The Eu(TTA)(3)(5-NH(2)-phen) with the characteristics of long lifetime and intense luminescence was labeled with reporter probe. The original extracted DNA samples without the purification and amplification process were directly used in the hybridization assay. The concentration of capture probe, hybridization temperature, hybridization and washing time were optimized. The detection limit is about 1.49x10(3) CFU mL(-1) E. coli cells, which is comparable to the value of most microbiology methods. The proposed method has the advantages of easy operation, satisfactory sensitivity and specificity, which can provide a promising technique for monitoring the microorganisms.

Directed shift of vaginal flora after topical application of sucrose gel in a phase III clinical trial: a novel treatment for bacterial vaginosis / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Bacterial vaginosis (BV) is one of the most common infectious diseases among sexually active women and is associated with the increased acquisition of a variety of sexually transmitted diseases. This study aimed to compare the efficacy of a non-antibiotic sucrose gel against an antibiotic metronidazole gel for the treatment of BV.</p><p><b>METHODS</b>A randomized, double-blinded, multi-center, parallel-group, placebo-controlled phase III clinical trial was conducted at eight hospitals in China. A total of 560 subjects with clinically diagnosed BV were randomly assigned into three groups for vaginally receiving sucrose, metronidazole, and placebo gels, respectively, twice daily for five consecutive days. The efficacy of therapeutic cure, defined as an achievement of both microbiologic cure (a Nugent score of 3 or less) and clinical cure (a resolution of the clinical findings from the baseline visit), was evaluated at the 1st and 2nd test-of-cure (TOC) visits at 7-10 and 21-35 days after the start of treatment, respectively.</p><p><b>RESULTS</b>Therapeutic cure rates for sucrose, metronidazole, and placebo gel groups were 83.13%, 71.30% and 0.92%, at the 1st TOC, and 61.04%, 66.67% and 7.34%, at the 2nd TOC, respectively. While there was no significant difference between the sucrose and metronidazole gel groups at the 2nd TOC (P = 0.305), and sucrose gel was more effective than metronidazole gel at the 1st TOC (P = 0.009).</p><p><b>CONCLUSION</b>These findings suggest that sucrose gel restores normal vaginal flora more rapidly than metronidazole gel and can be used as a novel treatment for BV.</p>

Time-resolved fluorescence based DNA detection using novel europium ternary complex doped silica nanoparticles.

A two-probe tandem DNA hybridization assay including capture DNA(1), probe DNA(2), and target DNA(3) was prepared. The long-lived luminescent europium complex doped nanoparticles (NPs) were used as the biomarker. The complex included in the particle was Eu(TTA)(3)(5-NH(2)-phen)-IgG (ETN-IgG), the europium complex Eu(TTA)(3)(5-NH(2)-phen) linking an IgG molecule. Silica NPs containing ETN-IgG were prepared by the reverse microemulsion method, and were easy to label oligonucleotide for time-resolved fluorescence assays. The luminophores were well-protected from the environmental interference when they were doped inside the silica network. The sequences of Staphylococcus aureus and Escherichia coli genes were designed using software Primer Premier 5.0. Amino-modified capture DNA(1) was covalently immobilized on the common glass slides surface. The detection was done by monitoring the fluorescence intensity from the glass surface after the hybridization reaction with the NPs labeled probe DNA(2) and complementary target DNA(3). The sensing system presented short hybridization time, satisfactory stability, sensitivity, and selectivity. This approach was successfully employed for preliminary application in the detection of pure cultured E. coli, it might be an effective tool for pathogen DNA monitoring.

Fluorescence sensor for water in organic solvents prepared from covalent immobilization of 4-morpholinyl-1, 8-naphthalimide.

A new fluorescent dye, N-allyl-4-morpholinyl-1,8-naphthalimide (AMN), was synthesized as a fluorescence indicator in the fabrication of a sensor for determining water content in organic solvents. To prevent leakage of the fluorophore, AMN was photo-copolymerized with acrylamide, (2-hydroxyethyl)methacrylate, and triethylene glycol dimethacrylate on a glass surface treated with a silanizing agent. The sensing mechanism is based on the solvatochromic feature of the covalently immobilized AMN. The fluorescence intensity of AMN decreased with increasing water contents when it was excited at 400 nm. In the range of ca. 0.00-4.40% (v/v), the fluorescence intensity of AMN changed as a linear function of water content. The sensor exhibited satisfactory reproducibility, reversibility, and a response time (t (99)) of the order of 50 s. The detection limit was solvent-dependent, when acetonitrile was used as the solvent, and the detection limit could be as low as 0.006% (v/v) of water. Additionally, the prepared sensor is pH-insensitive and possesses a relatively long lifetime of at least one month.

Fluorescence ratiometric pH sensor prepared from covalently immobilized porphyrin and benzothioxanthene.

A fluorescence ratiometric sensor for pH determination is described in this paper. The sensor incorporated the pH-sensitive dye meso-5,10,15,20-tetra-(4-allyloxyphenyl)porphyrin (TAPP) as an indicator and a pH-insensitive dye N-(2-methacryloxyethyl)benzo[k,l]thioxanthene-3,4-dicarboximide (MBTD), a benzothioxanthene derivative, as a reference for fluorescence ratiometric measurement. To prevent leakage of the dyes, both were photocopolymerized with acrylamide, hydroxyethyl methacrylate, and triethylene glycol dimethacrylate on the silanized glass surface. The reproducibility and response time of the prepared sensor were sufficient. Most common coexisting inorganic ions and organic compounds did not interfere with pH sensing. In the acidic pH range from 1.5 to 5.0 the fluorescence intensity ratio of the two dyes varied linearly as a function of pH. The sensing membrane was found to have a lifetime of at least one month. The sensor was applied to the analysis of waste water and artificial samples.