The application of gene splitting technique for controlling transgene flow in rice.

Controlling transgene flow in China is important, as this country is part of the center of origin of rice. A gene-splitting technique based on intein-mediated trans-splicing represents a new strategy for controlling transgene flow via biological measures. In this study, the G2-aroA gene which provides glyphosate tolerance was split into an N-terminal and a C-terminal region, which were then fused to intein N and intein C of the Ssp DnaE intein, ultimately forming EPSPSn:In and Ic:EPSPSc fusion genes, respectively. These fusion genes were subsequently transformed into the rice cultivar Zhonghua 11 via the Agrobacterium-mediated method. The two split gene fragments were then introduced into the same rice genome by genetic crossings. Glyphosate tolerance analysis revealed that the functional target protein was reconstituted by Ssp DnaE intein-mediated trans-splicing and that the resultant hybrid rice was glyphosate tolerant. The reassembly efficiency of the split gene fragments ranged from 67 to 91% at the molecular level, and 100% of the hybrid F1 progeny were glyphosate tolerant. Transgene flow experiments showed that when the split gene fragments are inserted into homologous chromosomes, the gene-splitting technique can completely avoid the escape of the target trait to the environment. This report is the first on the reassembly efficiency and effectiveness of transgene flow containment via gene splitting in rice. This study provides not only a new biological strategy for controlling rice transgene flow but also a new method for cultivating hybrid transgenic rice.

Effect on transcriptome and metabolome of stacked transgenic maize containing insecticidal cry and glyphosate tolerance epsps genes.

Gene stacking is a developing trend in agricultural biotechnology. Unintended effects in stacked transgenic plants are safety issues considered by the public and researchers. Omics techniques provide useful tools to assess unintended effects. In this paper, stacked transgenic maize 12-5×IE034 that contained insecticidal cry and glyphosate tolerance G10-epsps genes was obtained by crossing of transgenic maize varieties 12-5 and IE034. Transcriptome and metabolome analyses were performed for different maize varieties, including 12-5×IE034, 12-5, IE034, and conventional varieties collected from different provinces in China. The transcriptome results were as follows. The nine maize varieties had obvious differences in gene expression. There were 3561-5538 differentially expressed genes between 12-5×IE034 and its parents and transgenic receptor, which were far fewer than the number of differentially expressed genes in different traditional maize varieties. Cluster analysis indicated that there were close relationships between 12-5×IE034 and its parents. The metabolome results were as follows. For the nine detected maize varieties, the number of different metabolites ranged from 0 to 240. Compared with its parents, 12-5 and IE034, the hybrid variety 12-5×IE034 had 15 and 112 different metabolites, respectively. Hierarchical cluster analysis with Pearson's correlation analysis showed that the differences between 12-5×IE034 and its parents were fewer than those between other maize varieties. Shikimate pathway-related genes and metabolites analysis results showed that the effects of hybrid stacking are less than those from transformation and differing genotypes. Thus, the differences due to breeding stack were fewer than those due to natural variation among maize varieties. This paper provides scientific data for assessing unintended effects in stacked transgenic plants.

High Q-factor with the excitation of anapole modes in dielectric split nanodisk arrays.

The simultaneous realization of high Q-factor resonances and strong near-field enhancements around and inside of dielectric nanostructures is important for many applications in nanophotonics. However, the incident fields are often confined within dielectric nanoparticles, which results in poor optical interactions with external environment. Near-field enhancements can be extended outside of dielectric nanostructures with proper design, but the Q-factor is often reduced caused by additional radiation losses. This paper shows that the obstacles to achieve high Q-factor, that is, the radiative losses can be effectively suppressed by using dielectric nanodisk arrays, where the Q-factor is about one order larger than that of the single disks associated with the nonradiating anapole modes and the collective oscillations of the arrays. When the resonance energies of the electric dipole mode and the subradiant mode are degenerate with each other, the destructive interference produces an effect analogous to electromagnetically induced transparency. Furthermore, the Q-factor can be extremely enlarged with dielectric split nanodisk arrays, where the present of the split gap does not induce additional losses. Instead, the coupling between the two interfering modes is modified by adjusting the gap width, which makes it possible to achieve high Q-factor and strong near-field enhancements around and inside of the split disks simultaneously. It is shown that the Q-factor is approaching to 106 when the gap width is about 110 nm, and the near-field enhancements around and inside of the split disks are about two orders stronger than that of the single disk.

Self-standing boron nitride bulks enabled by liquid metals for thermal management.

Thermally conductive materials (TCMs) are highly desirable for thermal management applications to tackle the "overheating" concerns in the electronics industry. Despite recent progress, the development of high performance TCMs integrated with an in-plane thermal conductivity (TC) higher than 50.0 W (m K)-1 and a through-plane TC greater than 10.0 W (m K)-1 is still challenging. Herein, self-standing liquid metal@boron nitride (LM@BN) bulks with ultrahigh in-plane TC and through-plane TC were reported for the first time. In the LM@BN bulks, LM could serve as a bonding and thermal linker among the oriented BN platelets, thus remarkably accelerating heat transfer across the whole system. Benefiting from the formation of a unique structure, the LM@BN bulk achieved an ultrahigh in-plane TC of 82.2 W (m K)-1 and a through-plane TC of 20.6 W (m K)-1, which were among the highest values ever reported for TCMs. Furthermore, the LM@BN bulks exhibited superior compressive and leakage-free performances, with a high compressive strength (5.2 MPa) and without any LM leakage even after being crushed. It was also demonstrated that the excellent TCs of the LM@BN bulks made them effectively cool high-power light emitting diode modules. This work opens up one promising pathway for the development of high-performance TCMs for thermal management in the electronics industry.

Analysis of the influencing factors on fine-needle aspiration biopsy results of the thyroid.

Objective: The objective of the study is to analyze the influencing factors on the results of thyroid fine-needle aspiration biopsy (FNAB). Method: A total of 339 patients who underwent FNAB in our hospital from December 2018 to July 2021 were retrospectively selected. The patients were chosen according to the gender ratio, age, and thyroid ultrasound characteristics and were divided into three groups: (1) a 22G needle vacuum aspiration group (Group 1, n = 85), (2) a 22G biopsy needle non-vacuum aspiration group (Group 2, n = 50), and (3) a 25G biopsy needle non-vacuum aspiration group (Group 3, n = 204). Patients in these groups were evaluated for determining the FNAB dissatisfaction rate of pathological samples. A bivariate regression analysis of independent risk factors related to the unsatisfactory pathological diagnosis of samples was performed. Results: The specimen dissatisfaction rates of the three groups were 22/85 (25.9%), 15/50 (30%), and 18/186 (9.7%), respectively. The overall sample dissatisfaction rate was 55/339 (16.2%), and the sample satisfaction rate of Group 3 was higher than that of Groups 1 and 2 (P < 0.05). Logistic bivariate regression analysis showed that the age of the patients and the capillary sampling needles and aspiration methods were two independent risk factors for determining the dissatisfaction rate of FNAB pathological samples. Conclusion: A 25G capillary sampling aspiration biopsy needle was selected to perform FNAB in thyroid nodules without vacuum aspiration, which could effectively improve the accuracy of FNAB results with a high specimen satisfaction rate.

Whole-Genome Sequencing: An Effective Strategy for Insertion Information Analysis of Foreign Genes in Transgenic Plants.

Molecular characterization is a key step in the risk assessment of genetically modified organisms (GMOs) for regulatory approval. Herein, we describe a method for analyzing copy number, insertion loci, and flanking sequences through whole-genome sequencing (WGS) and bioinformatics. Comprehensive molecular characterization of G2-6 transgenic rice was performed using this pipeline. The results showed that one copy of the foreign gene was inserted into rice chromosome 8. There was no vector backbone insertion but an unexpected insertion and DNA rearrangement at the 3' end of the T-DNA. We also obtained the 5' and 3' flanking sequences of the T-DNA. Our results suggested that the use of a combination of WGS and bioinformatics is an effective strategy for the molecular characterization of GMOs.

[Feasibility and safety of right heart catheterization and pulmonary angiography through the antebrachium veins].

OBJECTIVE: To investigate the feasibility and safety of right heart catheterization through the antebrachium veins. METHODS: A total of 68 consecutive patients suspected with pulmonary vascular diseases underwent standard right heart catheterization and pulmonary angiography through the antebrachium veins were enrolled in this multicenter, cross-sectional study. RESULTS: The rate of successfully inserting the sheath into antebrachium veins was as high as 97.1% (66/68) and the rate of successfully performing right heart catheterization or pulmonary angiography through vascular access of antebrachium veins was 91.2% (62/68). The reasons of unsuccessful inserting the catheter to the right heart were due to the abnormality of antebrachium veins (2 cases) or stenosis of subclavian vein (3 cases) or unsatisfactory engorging of antebrachium veins since the history of drug injection (1 case). Haemorrhage of branch of axillary vein was the only adverse event occurred in one patient. CONCLUSION: It is a safe, convenient and well-tolerant option to perform right heart catheterization and pulmonary angiography through the vascular access of antebrachium veins.

[Application of surgical locating guides on impacted supernumerary teeth extraction].

OBJECTIVE: To study the application of surgical locating guides based on cone beam computed tomography (CBCT) and computer-aided design/computer-aided manufacturing (CAD/CAM) technique on extraction of impacted supernumerary teeth. METHODS: This study included 15 patients with impacted supernumerary teeth in anterior maxillary. Surgical approach was determined by CBCT. Surgical locating guides of labial approach or palatal approach were designed and fabricated by CAD/CAM technique. Impacted supernumerary teeth were extracted under the location of surgical locating guides. RESULTS: Surgical locating guides were well attached in the operation. The impacted supernumerary teeth were located and exposed rapidly, and the adjacent important anatomical structures were avoided. CONCLUSIONS: Surgical locating guides benefit the accurate detection and reduction of trauma in extraction of impacted supernumerary teeth.

Kinesin family member 20B regulates tongue cancer progression by promoting cell proliferation.

Oral cancer refers to the malignant tumors that occur in the oral cavity, of which 80% are squamous cell carcinomas. The incidence of oral cancer accounts for ~5% of the incidence of systemic malignancies, with rapid progression, extensive infiltration and poor prognosis. In the present study, Kinesin family member (KIF)20B, a member of Kinesin­6 family, was identified as a potential biomarker which could promote cancer progression. A total of 82 patients were recruited and KIF20B expression levels were investigated by immunohistochemistry, and were divided into high and low groups based on the median of KIF20B expression levels. The clinicopathological features and survival­associated data of the two groups were analyzed and the results were provided as a table and by a Kaplan­Meier plot, respectively. Additionally, KIF20B was successfully silenced in two tongue cancer cell lines, CAL­27 and TCA­8113. MTT and colony formation assay were performed to determine the changes of cell proliferation in knocked down­KIF20B cell lines. In addition, proliferation­associated proteins Ki67 and PCNA were investigated, by western blotting. In animal experiments, subcutaneous tumor formation was performed with control cells and cells with knocked down KIF20B, to determine the inhibitory effect of KIF20B in vivo. Firstly, it was found that there was significantly high expression levels of KIF20B in tongue cancer patients (P<0.05). Patients with high expression of KIF20B had poorer clinicopathological results including tumor differentiation level, lymph node metastasis and clinical stages. The overall survival and relapse­free survival of high­expression group were also poor. Secondly, after successful establishment of cells with knocked down KIF20B, this resulted in a notable reduction in cell proliferation in vitro. Subsequent western blotting further confirmed that Ki67 and PCNA expression levels had a significant decline. Finally, it was demonstrated that knocking down KIF20B could inhibit tumor volume growth in vivo. In conclusion, the high level of KIF20B in oral squamous cell carcinoma was significantly associated with poor clinicopathological features and survival. KIF20B might promote cancer development through enhancing cell proliferation in vitro, and might be a potential biomarker of oral squamous cell carcinoma.

Electrochemical Analysis for Enhancing Interface Layer of Spinel Li4Ti5O12: p-Toluenesulfonyl Isocyanate as Electrolyte Additive.

An electrolyte additive, p-toluenesulfonyl isocyanate (PTSI), is evaluated in our work to overcome the poor cycling performance of spinel lithium titanate (Li4Ti5O12) lithium-ion batteries. We find that the cycling performance of a Li/Li4Ti5O12 cell with 0.5 wt % PTSI after 400 cycles is obviously improved. Remarkably, we also find that a solid electrolyte interface (SEI) film is formed about 1.2 V, which has higher potential to generate a stable SEI film than do carbonate solvents in the voltage range of 3.0-0 V. The stable SEI film derived from PTSI can effectively suppress the decomposition of electrolyte, HF generation, interfacial reaction, and LiF formation upon cycling. These observations are explained in terms of PTSI including SO3. The S═O groups can delocalize the nitrogen core, which acts as the weak base site to hinder the reactivity of PF5. Hence, HF generation and LiF formation are suppressed.

Gene-splitting technology: a novel approach for the containment of transgene flow in Nicotiana tabacum.

The potential impact of transgene escape on the environment and food safety is a major concern to the scientists and public. This work aimed to assess the effect of intein-mediated gene splitting on containment of transgene flow. Two fusion genes, EPSPSn-In and Ic-EPSPSc, were constructed and integrated into N. tabacum, using Agrobacterium tumefaciens-mediated transformation. EPSPSn-In encodes the first 295 aa of the herbicide resistance gene 5-enolpyruvyl shikimate-3-phosphate synthase (EPSPS) fused with the first 123 aa of the Ssp DnaE intein (In), whereas Ic-EPSPSc encodes the 36 C-terminal aa of the Ssp DnaE intein (Ic) fused to the rest of EPSPS C terminus peptide sequences. Both EPSPSn-In and Ic-EPSPSc constructs were introduced into the same N. tabacum genome by genetic crossing. Hybrids displayed resistance to the herbicide N-(phosphonomethyl)-glycine (glyphosate). Western blot analysis of protein extracts from hybrid plants identified full-length EPSPS. Furthermore, all hybrid seeds germinated and grew normally on glyphosate selective medium. The 6-8 leaf hybrid plants showed tolerance of 2000 ppm glyphosate in field spraying. These results indicated that functional EPSPS protein was reassembled in vivo by intein-mediated trans-splicing in 100% of plants. In order to evaluate the effect of the gene splitting technique for containment of transgene flow, backcrossing experiments were carried out between hybrids, in which the foreign genes EPSPSn-In and Ic-EPSPSc were inserted into different chromosomes, and non-transgenic plants NC89. Among the 2812 backcrossing progeny, about 25% (664 plantlets) displayed glyphosate resistance. These data indicated that transgene flow could be reduced by 75%. Overall, our findings provide a new and highly effective approach for biological containment of transgene flow.

The efficacy and safety of sildenafil in Chinese patients with pulmonary arterial hypertension.

Sildenafil has been suggested to be a cost-effective treatment for pulmonary arterial hypertension (PAH). On account of the lack of data confirming its benefit in PAH patients, sildenafil has not been adopted in China for the treatment of PAH. The purpose of this study was to evaluate the efficacy, safety and 1-year survival of Chinese patients with PAH treated with sildenafil. Sixty Chinese patients with PAH were enrolled in this preliminary study. Their 6-min walk distance, WHO functional class and hemodynamic parameters (such as right atrial pressure, pulmonary arterial pressure, cardiac index and pulmonary vascular resistance) at both baseline and 16 weeks after initiation of sildenafil treatment were recorded. In addition, 1-year overall survival was assessed in this cohort. The 6-min walk distance improved from 392.13+/-91.35 to 467.22+/-80.38 m during the course of treatment (P<0.001). There was a significant decrease in the mean pulmonary vascular resistance (15.28+/-8.12-14.99+/-7.88 Woods units; P=0.02) and a significant increase in the mean cardiac index (2.39+/-0.90-2.75+/-0.92 l/min/m(2), P=0.006) of the included patients at 16 weeks. The mean systemic oxygen saturation improved significantly at 16 weeks (91.44+/-7.54%-94.11+/-4.28%; P=0.002). No serious adverse reactions were reported. The Kaplan-Meier analysis showed that the 1-year survival rate improved significantly in the sildenafil-treated cohort compared with predicted survival (94.7% compared with 63.3%, P=0.03). In conclusion, sildenafil may be a safe and effective treatment for Chinese PAH patients. Sildenafil, when added to conventional therapy, was associated with improvements in exercise capacity, hemodynamic parameters and overall survival in a cohort of Chinese patients with PAH.