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BACKGROUND: 'Gold Finger' is a grape cultivar with a finger‐like shape and a milk flavor. The process by which its aroma profile evolves during ripening is unclear. Thus, changes in the free and bound volatile compounds present in 'Gold Finger' grapes during ripening were investigated using headspace sampling–solid‐phase microextraction–gas chromatography–mass spectroscopy (HS‐SPME‐GC‐MS). RESULTS: A total of 83 volatile aroma components were identified in the grapes, with aldehydes, esters, acids, and alcohols being the main components. The total aroma compound content exhibited significant differences between the bound and free forms. The total content of bound volatile compounds did not change significantly during fruit development, although the free aroma compound content was significantly higher than the bound content. The total content of free aldehydes, free alcohols, bound norisoprenoids, and ketones gradually increased for up to 70 days after flowering (DAF), while the total free ester, terpene, and acid content decreased. The characteristic aroma compounds of 'Gold Finger' grapes were identified as hexanal, (E)‐2‐hexenal, and ethyl hexanoate. CONCLUSIONS: These results give a foundation for the further development of 'Gold Finger' grapes and provide a theoretical basis for the selection and breeding of novel aromatic grape varieties. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Previously, VpPR-10.1 was isolated and characterized from a cDNA library of a fungus-resistant accession of Chinese wild grape (Vitis pseudoreticulata). We found that expression of VpPR-10.1 is affected by the fungal pathogen Erysiphe necator. To investigate the biochemical basis of the nuclease activity of VpPR-10.1 and its role in antifungal resistance, we generated recombinant VpPR-10.1 as well as site-directed mutations targeting three conserved amino acid residues among plant PR-10 s: Lys55, Glu149, and Tyr151. We showed that wild-type recombinant VpPR-10.1 exhibits both RNase and DNase activities. Mutant VpPR10.1-Y151H essentially retained all these activities. In contrast, VpPR10.1-K55N, where Lys55 in the P-loop region is mutated to Asn, and VpPR10.1-E149G, where Glu149 is mutated to Gly, lost their nuclease activity, indicating that both residues play a critical role in catalyzing RNA and DNA degradation. Furthermore, VpPR10.1 and VpPR10.1-Y151H inhibited the growth of the cultured fungal pathogen Alternaria alternate. Through transient expression in grapevine, we also demonstrated that VpPR10.1-K55N and VpPR10.1-E149G compromised resistance to E. necator. Finally, we further found that VpPR-10.1 can lead to programmed cell death and DNA degradation when incubated with tobacco BY-2 suspension cells. We show here that Lys55 and Glu149, but not Tyr151, are required for the RNase, DNase and antifungal activities of VpPR-10.1. The strong correlation between the level of VpPR-10.1 nuclease activity and its antifungal property indicates that the former is the biochemical basis for the latter. Taken together, our experiments revealed that VpPR-10.1 is critical in mediating fungal resistance in grape, potentially playing a dual role by degrading pathogen RNA and inducing programmed death of host cells. [ABSTRACT FROM AUTHOR]

The close form exact solutions of free vibrations of thin orthotropic rectangular plates on the Pasternak elastic foundation or the elastic foundation with two parameters are solved by means of separation of variables method. It is noteworthy that the exact solutions for the plates with boundary conditions CCCC, SCCC and SSCC ( S denotes simple support, and C denotes clamp) were considered impossible to be solved. In separation of variables method, the general formulation of the natural mode and the relationship among the two spatial eigenvalues and the temporal eigenvalue are directly obtained from the governing differential equation, and the coefficients of the exact eigenfunctions and the exact eigenvalue equations are determined on the basis of boundary conditions. The numerical results agree well with those in literature and FEM, this validates the correctness of the present method. [ABSTRACT FROM AUTHOR]

Objective: To study the application of three-dimensional reconstruction technique based on CT-MRI fusion in skull base surgery., Methods: To acquire the thin layer CT scan and MRI scanned images, to achieve image registration, fusion, segmentation and 3D visualization by using self-preparation software, to operate, observe and measure models by using methods of endoscopic observation, volume rendering segmentation, automatically and manually measure., Results: The center of the eye and foramen magnum in CT-MRI were used as point registration. Good coincidence of important anatomic landmarks were formed in the image fusion. The boundary of spotted graphical was clear and complete. The models showed a complete, continuous, smooth surface. Virtual endoscopy could display the inside three-dimensional structures of skull from nasal with fluent operations of rotation and transparency. The boundary of skull stump segmented after volume rendering segmentation was clear and smooth, and it could show bone signs and soft tissue models together. Cooperation of automatic measurement method [(32.007 ± 15.311) mm] and the manual measurement method [(30.240 ± 15.169) mm] for measuring the maximum diameters of the tumor model, the difference was significant (t = 8.409, P < 0.05)., Conclusions: The method of selecting the center of the eye and foramen magnum in point matching is scientific, simple and easy to operate. The models reconstructed based on CT-MRI fusion images can accurately reflect the size of the soft tissue and be better measured through the automatic measurement. Reconstruction models can be observed through the way of virtual endoscopic within the nasal cavity or volume rendering segmentation from outside to inside to frustrate the relationship of skull structures. Three-dimensional reconstruction techniques based on CT-MRI fusion in skull base surgery can be used to plan surgical approach, to assess the risk of surgery and to achieve space measurements, and it laid the foundation for the three-dimensional navigation.

Aim: To construct a shuttle plasmid encoding a chimeric gene of Clostridium saccharobutylicum eglA promoter(eglA p)-extracellular domain of human epidermal growth factor receptors 2(hHer2/neu ECD)-human Interleukin-12(rhIL-12), pIMP1 eglA p-hHer 2/neu ECD-rhIL-12., Methods: The hHer2/neu ECD and the eglA p was amplified from the corresponding template: pcDNA3.1 hHer2/neu and 55 bp fragment in eglA p by PCR. pcDNA6 eglA p-hHer2/neu ECD-rhIL-12 was prepared by inserting the hHer2/neu ECD and eglAp fragment into the plasmid, pcDNA6 rhIL-12. Shuttle plasmid pIMP1 eglA p-hHer2/neu ECD-rhIL-12 was acquired by using in-fusion technique. subsequently, the recombinant shuttle plasmid was identified., Results: All the fragments of hHer2/neu ECD , eglA p and eglAp-Her2/neu ECD-rhIL-12 were amplified, and the corresponding plasmids were prepared rightly. The shuttle plasmid of pIMP1 eglAp-hHer2/neu ECD-rhIL-12 was successfully const- ructed. No error was found both in the sequence and ORF of the acquired chimeric gene., Conclusions: A shuttle plasmid encoding a chimeric gene of Clostridium saccharobut- ylicum eglAp-hHer2/neu ECD-rhIL-12(pIMP1 eglA p-hHer2/neu ECD-rhIL- 12) was success- fully constructed.

Aim: To construct an eukaryotic vector encoding extracellular domain of human epidermal growth factor receptors (HER2), pcDNA6/v5-his-HER2, and to screen HER2 positive clones from mouse breast cancer cell line EMT6., Methods: The extracellular domain of HER2 was amplified from pcDNA3.1-HER2 by PCR. pcDNA6/v5-his-HER2 was prepared by inserting the fragment into the plasmid pcDNA6/v5-his. Then the recombinant vector was identified by restriction enzyme and sequencing. Next, pcDNA6/v5-his-HER2 was transfected into the EMT6 cell line and the positive clones (EMT6/HER2) were screened with blasticidin. Finally, the expression of HER2 in EMT6/HER2 was detected by RT-PCR and immunohistochemistry., Results: The fragment of HER2 was amplified and pcDNA6/v5-his-HER2 was prepared successfully. No errors were found both in the sequence and ORF of the acquired fragment. The expected fragment of HER2 (1896 bp) was amplified from EMT6/HER2 by RT-PCR and positive signals of HER2 were detected in EMT6/HER2 by immunohistochemistry., Conclusion: An eukaryotic plasmid encoding HER2 (pcDNA6/v5-his-HER2) has been constructed and a cell line expressing HER2 stably has been prepared successfully.

The aim of this project was to investigate the anti-tumor effect of an IL-12 gene modified mammary sarcoma murine cell line, EMT6/IL-12, in mouse model. In this study, we transfected the recombinant eukaryotic plasmid encoding IL-12 gene (pcDNA6-p70) into EMT6 and obtained the IL-12 expressing EMT6/IL-12 cell line. Then EMT6/IL-12 cells were s.c. inoculated into mice. The recombinant vector treatment group was set as control. We then evaluated the inhibition of tumor growth and the anti-tumor immunity function in vivo such as cytotoxicity, proliferation of splenocytes and serial IFN-gamma level. And the percentage of IFN-gamma producing CD4 or CD8 T cells among splenocytes was also analyzed in tumor bearing mice. Our results showed that the growth of tumors was obviously inhibited in EMT6/IL-12 group. Moreover, the capacities of anti-tumor immunity were all significantly higher in EMT6/IL-12 group compared to the controls. The results of the present investigation support the notion that EMT6/IL-12 could exert gene therapy in tumor model by improving the anti-tumor cellular immunity.