[Cloning and expression analysis in resurrection process of trehalose-6-phosphate synthase gene from Selaginella tamariscina].

Selaginella tamariscina is a typical resuscitation medicinal plant with extreme drought tolerance. Trehalose plays an important role in the resurrection process, and the trehalose-6-phosphate synthase(TPS) is the key enzyme to synthesize trehalose in plants. In this study, the sequence of TPS was obtained by splicing from the transcriptome data of S. tamariscina. After the synthesis of cDNA based on the template of total RNA, the sequence was cloned by RT-PCR for verification and then analyzed by bioinformatics methods. The results indicated that the full-length coding sequence of StTPS was 2 799 bp (GenBank accession no. MH155231), and the encoded protein contained 932 amino acids. StTPS could be located in the chloroplastid according to subcellular localization prediction. There were two conserved domains belonging to glycogen phosphorylase glycosyltransferase (GPGTF) family but no signal peptide or transmembrane domain in StTPS. The expression of StTPS was determined by qRT-PCR and the variation of trehalose content was measured by HPLC-ELSD during the resurrection process of S. tamariscina. Meanwhile, the correlation between them was analyzed. The results showed that both the expression level of StTPS and the trehalose content increased associated with the extension of dehydration time, and declined associated with the extension of rehydration time which proved a significant positive correlation between the StTPS expression level and the trehalose content. The results suggested that the StTPS probably plays a central role in recovery process in S. tamariscina.

[Prokaryotic expression, functional identification of squalene synthase in Alisma orientale and its immunoassay study].

Squalene synthase of Alisma orientale catalyzes farnesyl diphosphate (FPP) to form squalene, which is the key regulatory enzyme of the carbon source flow to protostane triterpenes biosynthesis. For further research on the function and expression of AoSS gene, the open reading frame (ORF) of squalene synthase gene (accession no. JX866770) from A. orientale was subcloned into a prokaryotic expression vector pCzn1 and induced the expression of AoSS gene in Escherichia coli BL21(Roseta). The fusion protein was mainly in the form of inclusion bodies and purified to obtain high purity protein. By verifying its functionality through vitro enzymatic reaction, the results showed that the catalytic protein had the catalytic activity of FPP into squalene. In order to research the expression of AoSS in A. orientale, the purified protein was used to immunized rabbits to prepare polyclonal antibody which was then purified, the titer of the antibody was greater than 1∶51 200 by ELISA detection, and displayed good specificity by Western blotting. The prepared antibody was used for immunoassay of AoSS in different organs of A. orientale, and the results showed that the AoSS expression level was the highest in tubers, followed by leaves, and lowest in root. Successful construction of prokaryotic expression vector, validation of gene functions and establishment of rapid immunoassay lay the foundation for further researches on the function and regulation of AoSS gene, and also provide scientific basis on the application of the protostane triterpenes of A. orientale in the field of synthetic biology.

[Effects of GLP-1 Agonist Exenatide on Cardiac Diastolic Function and Vascular Endothelial Function in Diabetic Patients].

OBJECTIVE: To study the protective effect of glucagon-like peptide-1 (GLP-1) on the left ventricular diastolic function and endothelial function in patients with type 2 diabetes. METHODS: 27 patients with type 2 diabetes were randomly divided into two groups: GLP-1 treated group and insulin treated group. Patients in the GLP-1 group were given GLP-1 analogue and metformin hydrochloride. Patients in the insulin group were given insulin and metformin hydrochloride. The outcomes of treatments were measured by fasting plasma glucose (FBG) fasting lipid profile, glycosylated hemoglobin (HbA1c), blood pressure and general clinical features. High resolution Doppler ultrasound was performed to detect mitral early diastolic rapid filling (E-wave), atrial contraction late filling (A-wave), E/A ratio, early diastolic mitral annular velocity (e), late diastolic mitral annular velocity (a), e/a ratio, endothelium-dependent vasodilatation (EDV) mediated by brachial arterial blood flow, and endothelium-independent vasodilatation (EIV) mediated by nitroglycerin. RESULTS: The levels of FBG and HbA1c decreased significantly in both groups after treatments (P < 0.05). Patients in the GLP-1 group showed improved e, e/a ratio, and E/e ratio after treatments (P < 0.05), but no significant changed in E, A, and E/A ratio (P > 0.05). By contrast, patients in the insulin group showed no significant changes in e, a, E, A, E/A ratio, e/a ratio and E/e ratio after treatments (P > 0.05). EDV increased significantly after treatments in both groups (P < 0.05). A higher level of post-treatment EDV was found in patients in the GLP-1 group compared with those in the insulin group. No significant changes in EIV were found in both groups. CONCLUSION: GLP-1 may be able to mitigate the left ventricular diastolic dysfunction and improve endothelial function of patients with type 2 diabetes. Our findings suggest that GLP-1 has the potential to prevent or delay cardiovascular complications in patients with type 2 diabetes. Further studies are needed.

Mixed mode of artificial liver support in patients with acute-on-chronic liver failure: a retrospective cohort study.

BACKGROUND AND AIMS: Different modes of artificial liver support (ALS) therapy can improve the survival of patients with acute-on-chronic liver failure (ACLF). This study aimed to compare the effects of mixed using different modes of ALS (MALS) and single using one mode of ALS (SALS) on 28- and 90-day survival rates of ACLF. METHODS: Clinical data and survival times of patients with ACLF treated for ALS between January 1, 2018 and December 30, 2021 were retrospectively collected. Cox regression analysis was performed to identify risk factors of 28- and 90-day mortalities. RESULTS: Of the 462 eligible ACLF patients, 388 belonged to the SALS group (76.3% male, 74.2% cirrhosis) and 74 to the MALS group (86.5% male, 71.6% cirrhosis). Comparison of 28-day and 90-day crude mortality between the SALS and MALS groups showed no significant differences (28-day: 20.4% vs. 14.9%, p = 0.27; 90-day: 44.6% vs. 52.7%, p = 0.20). After adjusting for confounders, the 28-day mortality (adjusted hazard ratio [aHR]: 0.32, 95% confidence interval [CI] 0.16-0.65) and 90-day mortality (aHR: 0.65, 95% CI 0.44-0.95) in the MALS group were significantly lower than those in the SALS group. These associations were consistently observed across pre-specified subgroups according to age, sex, etiology, and Child-Pugh grade. However, positive interactions between MALS and 90-day mortality were found between MALS and 90-day mortality in those with MELD score ≥ 22 and international normalized ratio ≥ 1.9 (p for interaction < 0.05). CONCLUSION: MALS therapy significantly decreased 28- and 90-day mortalities of ACLF than SALS did, especially in advanced stages.

Discontinuous Track Recognition System Based on PolyLaneNet for Darwin-op2 Robot.

This paper proposes and demonstrates a single-line discontinuous track recognition system by associating the track recognition problem of a humanoid robot with the lane detection problem. The proposal enables the robot to achieve stable running on the single-line discontinuous track. The system consists of two parts: the robot end and the graphics computing end. The robot end is responsible for collecting track information and the graphics computing end is responsible for high-performance computing. These two parts use the TCP for communication. The graphics computing side uses PolyLaneNet lane detection algorithm to train the track image captured from the first perspective of the darwin-op2 robot as the data set. In the inference, the robot end sends the collected tracking images to the graphics calculation end and uses the graphics processor to accelerate the calculation. After obtaining the motion vector, it is transmitted back to the robot end. The robot end parses the motion vector to obtain the motion information of the robot so that the robot can achieve stable running on the single-line discontinuous track. The proposed system realizes the direct recognition of the first perspective image of the robot and avoids the problems of poor stability, inability of identifying curves and discontinuous lines, and other problems in the traditional line detection method. At the same time, this system adopts the method of cooperative work between the PC side and the robot by deploying the algorithm with high computational requirements on the PC side. The data transmission is carried out by stable TCP communication, which makes it possible for the robot equipped with weak computational controllers to use deep-learning-related algorithms. It also provides ideas and solutions for deploying deep-learning-related algorithms on similar low computational robots.

Comparison of Gemcitabine Plus Cisplatin vs. Docetaxel Plus Fluorouracil Plus Cisplatin Palliative Chemotherapy for Metastatic Nasopharyngeal Carcinoma.

Objective: Our study aimed to compare the efficacy and toxicity of two chemotherapy regimens, gemcitabine plus cisplatin (GP) vs. docetaxel plus, fluorouracil plus cisplatin (TPF), in metastatic nasopharyngeal carcinoma (NPC) patients. Methods: We retrospectively enrolled metastatic NPC patients between July 2006 and December 2016 who were treated with TPF or GP palliative chemotherapy (PCT). The association between the PCT regimens and survival conditions was evaluated by log-rank tests and the Cox proportional hazards model. A cohort was created using propensity score matching with the ratio of 1:1 to clarify the results of the multivariable Cox regression analyses. Overall survival (OS) was the primary endpoint. Results: Of 266 eligible patients, 186 and 80 patients, respectively, received TPF and GP regimen. No significant difference was demonstrated in the survival rate between the GP and TPF groups (3-year OS: 52.6 vs. 50.3%; P = 0.929). However, multivariable analysis suggested receiving GP as an independent protective factor (hazard ratio, 0.864; 95% confidence interval, 0.753-0.992; P = 0.042). In the matched cohort, treatment with GP was also associated with a significantly higher OS (3-year OS: 52.6 vs. 35.6%, P = 0.042). Subgroup analysis indicated that the superiority of GP reflected in patients with secondary metastases rather than primary metastases. The incidence of grade 3 to 4 treatment-related toxicity was more common in the TPF group than in the GP group. Conclusion: Our study suggested that GP might be superior to TPF for metastatic NPC patients, especially those with secondary distant metastases. Further studies are necessary to validate our results.