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Dioscorea alata L. (Dioscoreaceae), commonly known as greater yam, water yam, or winged yam, is a popular tuber vegetable/food crop worldwide, with nutritional, health, and economical importance. China is an important domestication center of D. alata, and hundreds of cultivars (accessions) have been established. However, genetic variations among Chinese accessions remain ambiguous, and genomic resources currently available for the molecular breeding of this species in China are very scarce. In this study, we generated the first pan-plastome of D. alata, based on 44 Chinese accessions and 8 African accessions, and investigated the genetic variations, plastome evolution, and phylogenetic relationships within D. alata and among members of the section Enantiophyllum. The D. alata pan-plastome encoded 113 unique genes and ranged in size from 153,114 to 153,161 bp. A total of four whole-plastome haplotypes (Haps I–IV) were identified in the Chinese accessions, showing no geographical differentiation, while all eight African accessions shared the same whole-plastome haplotype (Hap I). Comparative genomic analyses revealed that all four whole plastome haplotypes harbored identical GC content, gene content, gene order, and IR/SC boundary structures, which were also highly congruent with other species of Enantiophyllum. In addition, four highly divergent regions, i.e., trnC–petN, trnL–rpl32, ndhD–ccsA, and exon 3 of clpP, were identified as potential DNA barcodes. Phylogenetic analyses clearly separated all the D. alata accessions into four distinct clades corresponding to the four haplotypes, and strongly supported that D. alata was more closely related to D. brevipetiolata and D. glabra than D. cirrhosa, D. japonica, and D. polystachya. Overall, these results not only revealed the genetic variations among Chinese D. alata accessions, but also provided the necessary groundwork for molecular-assisted breeding and industrial utilization of this species.

Industrial synthesis of primary amine often features poor selectivity because of the formation of secondary and tertiary amine byproducts. Here, the authors report an electrocatalytic route to ethylamine through selective electroreduction of acetonitrile at ambient temperature and pressure.

The Minimum Mean-Square Error (MMSE) detector can achieve excellent Bit Error Rate (BER) performance in massive Multiple-Input Multiple-Output (MIMO) systems. However, it involves high complexity large-scale matrix inversion operation with high degree, resulting in very high hardware requirements. To solve this problem, the article proposes a Generalized Weighted-Preconditioned Gauss-Seide (GS) (GW-PGS) iterative algorithm. In this algorithm, an initialization scheme based on preprocessing is first proposed, which speeds up the convergence speed without adding additional complexity. In addition, this paper proposes an adaptive weighting factor scheme. The experimental results show that compared with the traditional GS algorithm, the algorithm proposed in this paper can effectively reduce the BER and computational complexity.

Summary: Background: Pancreatic ductal adenocarcinoma (PDAC) is a malignant tumor with an extremely poor prognosis. Effective targets for anticancer therapy confirmed in PDAC are limited. However, the characteristics of genomics have not been fully elucidated in large-scale patients with PDAC from China. Methods: We collected both blood and tissue samples from 1080 Chinese patients with pancreatic cancer and retrospectively investigated the genomic landscape using next-generation sequencing (NGS). Findings: We found recurrent somatic mutations in KRAS (83.2%), TP53 (70.6%), CDKN2A (28.8%), SMAD4 (23.0%), ARID1A (12.8%) and CDKN2B (8.9%) in Chinese PDAC patients. Compared with primary pancreatic cancers, more genomic alterations accumulated especially cell cycle regulatory gene variants (45.4% vs 31.6%, P < 0.001) were observed in metastatic tumors. The most common mutation site of KRAS is p.G12D (43.6%) in pancreatic cancer. Patients with KRAS mutations were significantly associated with older age and mutations in the other three driver genes, while KRAS wild-type patients contained more fusion mutations and alternative mechanisms of RTK/Ras/MAPK pathway including a number of clinically targetable mutations. KRAS mutations in Chinese cohort were significantly lower than those in Western cohorts (all P < 0.05). A total of 252 (23.3%) patients with the core DNA damage response (DDR) gene mutations were detected. ATM (n =59, 5.5%) was the most frequent mutant DDR gene in patients with pancreatic cancer from China. Patients with germline DDR gene mutations were younger (P = 0.018), while patients with somatic DDR gene mutations were more likely to accumulate in metastatic lesions (P < 0.001) and had higher TMB levels (P < 0.001). In addition, patients with mutant DDR genes and patients carrying TP53 mutation were observed mutually exclusive (P < 0.001). Interpretation: We demonstrated the real-world genomic characteristics of large-scale patients with pancreatic cancer from China which may have promising implications for further clinical significance and drug development. Funding: The funders are listed in the Acknowledgement.

Gene activation is a random process, modelled as a framework of multiple rate-limiting steps listed sequentially, in parallel or in combination. Together with suitably assumed processes of gene inactivation, transcript birth and death, the step numbers and parameters in activation frameworks can be estimated by fitting single-cell transcription data. However, current algorithms require computing master equations that are tightly correlated with prior hypothetical frameworks of gene activation. We found that prior estimation of the framework can be facilitated by the traditional dynamical data of mRNA average level M(t), presenting discriminated dynamical features. Rigorous theory regarding M(t) profiles allows to confidently rule out the frameworks that fail to capture M(t) features and to test potential competent frameworks by fitting M(t) data. We implemented this procedure for a large number of mouse fibroblast genes under tumour necrosis factor induction and determined exactly the ‘cross-talking n-state’ framework; the cross-talk between the signalling and basal pathways is crucial to trigger the first peak of M(t), while the following damped gentle M(t) oscillation is regulated by the multi-step basal pathway. This framework can be used to fit sophisticated single-cell data and may facilitate a more accurate understanding of stochastic activation of mouse fibroblast genes.

To study the immunomodulatory effect of jujube polysaccharide on mouse lymphocytes. Mouse lymphocytes were sterile separated， cell suspension was prepared， and the blank group， the positive group(levamisole) and the jujube polysaccharide group with different mass concentrations (final concentrations of 20， 40， 80， 160 and 320 living μg/ml) were designed. The effect of jujube polysaccharide on the proliferation of mouse lymphocytes was observed by MTT method. The effects of jujube polysaccharide on the levels of interleukin-2 (IL-2)， interleukin-6 (IL-6)， interleukin-10 (IL-10) and interleukin-12 (IL-12) in the supernatant of mouse lymphocytes were observed by ELISA. The effect of jujube polysaccharide on the expression of IL-2， IL-6， IL-10 and IL-12 mRNA in mouse lymphocytes was detected by QRT-PCR. Jujube polysaccharide could promote the proliferation of mouse lymphocytes and the secretion of cytokines in the range of 20-320 μg/ml， which further promoted the expression of cytokines IL-2 and IL-6， as well as IL-10 and IL-12 mRNA.Conclusion: jujube polysaccharide enhances immune function by inducing lymphocyte proliferation and the secretion and mRNA expression of lymphocyte cytokines IL-2 and IL-6， as well as IL-10 and IL-12.

Previous studies demonstrate an accumulation of transferrin and transferrin receptor 1 (TfR1) in regenerating peripheral nerves. However, the expression and function of transferrin and TfR1 in the denervated skeletal muscle remain poorly understood. In this study, a mouse model of denervation was produced by complete tear of the left brachial plexus nerve. RNA-sequencing revealed that transferrin expression in the denervated skeletal muscle was upregulated, while TfR1 expression was downregulated. We also investigated the function of TfR1 during development and in adult skeletal muscles in mice with inducible deletion or loss of TfR1. The ablation of TfR1 in skeletal muscle in early development caused severe muscular atrophy and early death. In comparison, deletion of TfR1 in adult skeletal muscles did not affect survival or glucose metabolism, but caused skeletal muscle atrophy and motor functional impairment, similar to the muscular atrophy phenotype observed after denervation. These findings suggest that TfR1 plays an important role in muscle development and denervation-induced muscular atrophy. This study was approved by the Institutional Animal Care and Use Committee of Beijing Institute of Basic Medical Sciences, China (approval No. SYXK 2017-C023) on June 1, 2018.

Abstract In the status of obesity, the glucagon-like peptide-1 (GLP-1) level usually declines and results in metabolic syndrome. This study aimed to investigate the intracellular mechanism of GLP-1 synthesis in L cells from the perspective of microRNA (miRNA). In the present study, we found that GLP-1 level was down-regulated in the plasma and ileum tissues of obese mice, while the ileac miR-194 expression was up-regulated. In vitro experiments indicated that miR-194 overexpression down-regulated GLP-1 level, mRNA levels of proglucagon gene (gcg) and prohormone convertase 1/3 gene (pcsk1), and the nuclear protein level of beta-catenin (β-catenin). Further investigation confirmed that β-catenin could promote gcg transcription through binding to transcription factor 7-like 2 (TCF7L2). miR-194 suppressed gcg mRNA level via negatively regulating TCF7L2 expression. What’s more, forkhead box a1 (Foxa1) could bind to the promoter of pcsk1 and enhanced its transcription. miR-194 suppressed pcsk1 transcription through targeting Foxa1. Besides, the interference of miR-194 reduced palmitate (PA)-induced cell apoptosis and the anti-apoptosis effect of miR-194 inhibitor was abolished by TCF7L2 knockdown. Finally, in HFD-induced obese mice, the silence of miR-194 significantly elevated GLP-1 level and improved the metabolic symptoms caused by GLP-1 deficiency. To sum up, our study found that miR-194 suppressed GLP-1 synthesis in L cells via inhibiting TCF7L2-mediated gcg transcription and Foxa1-mediated pcsk1 transcription. Meanwhile, miR-194 took part in the PA-induced apoptosis of L cells.

AIM: To explore the clinical value of fundus retinal argon laser photocoagulation combined with calcium dobesilate in the treatment of diabetic retinopathy(DR).METHODS:A prospective study from August 2017 to August 2019 was conducted. Totally 182 patients(326 eyes)with DR were divided into two groups. The observation group received fundus retinal argon laser photocoagulation combined with calcium dobesilate, and the control group received fundus retinal argon laser photocoagulation. Flash electroretinography was performed before treatment and after treatment, and changes in a and b waves were recorded. Changes in the best corrected visual acuity(BCVA), retinal neovascularization fluorescein leakage area, central macular thickness(CMT)and retinal microcirculation parameters were detected. The absorption time of retinal edema, bleeding and exudation was recorded, and the incidence of postoperative complications was counted.RESULTS: At 6mo after treatment, a-wave and b-wave amplitudes of the two groups were decreased(P0.05). The BCVA of the two groups was increased, and the macular leakage area and CMT were reduced(P0.05).CONCLUSION: Fundus retinal argon laser photocoagulation combined with calcium dobesilate is superior to retinal photocoagulation alone in the treatment of DR. The former can promote the improvement of visual acuity, reduce fluorescein leakage, and promote the absorption of retinal edema, bleeding and exudation, which is conductive to improving retinal microcirculation and inhibiting neovascularization.

Objective: Pancreatic ductal adenocarcinoma (PDAC) is a disease with high mortality. Many so-called “junk” noncoding RNAs need to be discovered in PDAC. The purpose of this study was therefore to investigate the function and regulatory mechanism of the long noncoding RNA MEG3 in PDAC. Methods: The Gene Expression Omnibus database (GEO database) was used to determine the differential expression of long noncoding RNAs in PDAC, and MEG3 was selected for subsequent verification. Tissue and cell samples were used to verify MEG3 expression, followed by functional detection in vitro and in vivo. Microarrays were used to characterize long noncoding RNA and mRNA expression profiles. Competing endogenous RNA analyses were used to detect differential MEG3 and relational miRNA expression in PDAC. Finally, promoter analyses were conducted to explain the downregulation of MEG3 PDAC. Results: We generated a catalogue of PDAC-associated long noncoding RNAs in the GEO database. The ectopic expression of MEG3 inhibited PDAC growth and metastasis in vitro and in vivo, which was statistically significant (P < 0.05). Microarray analysis showed that multiple microRNAs interacted with MEG3. We also showed that MEG3, as a competing endogenous RNA, directly sponged miR-374a-5p to regulate PTEN expression. The transcription factor, Sp1, recruited EZH2 and HDAC3 to the promoter and transcriptionally repressed MEG3 expression. Finally, clinical data showed that MEG3 and miR-374a-5p expressions were correlated with clinicopathological features. Statistically, Sp1, EZH2, HDAC3, and miR-374a-5p were negatively correlated with MEG3 (P < 0.05). Conclusions: Reduced MEG3 levels played a crucial role in the PDAC malignant phenotype, which provided insight into novel and effective molecular targets of MEG3 for pancreatic cancer treatment.

Understanding the impact of nitrogen oxides, common contaminants in CO2 emission from industries is a key to commercializing CO2 electrolysis technologies. Here, the authors conduct an investigation of CO2 electroreduction on copper, silver, and tin catalysts in the presence of nitric oxide, nitrogen dioxide, or nitrous oxide.

Backgound:Angelicae pubescentis is the root of Angelica pubescens Maxim. f. biserrata Shan et Yuan. The main active ingredients are coumarin and volatile oil, and it has a variety of pharmacological activities such as antibacterial, antioxidant and anti-inflammatory. In this paper, the active components of the CO2 supercritical extract of Angelicae pubescentis were studied. The results of this study will provide a scientific basis for the study of the chemical composition of Angelicae pubescentis. Purpose: To study the chemical constituents of supercritical extract of Radix Angelicae pubescentis. Method: The supercritical extract of Radix Angelicae pubescentis was separated by silica gel column chromatography to obtain monomers. The structures were identified based on physicochemical properties and spectroscopic data. Result: Eight compounds were separated from the supercritical extract of Radix Angelicae pubescentis, six of which were identified.They are Osthol, Columbianedin, Columbianetin, Columbianetin Acetate, Xanthotoxin and Bergapten. Conclusion: Xanthotoxin and Bergapten were isolated, which structure were similar. The standard substance of Osthol and Columbianedin were producted in order to offer the good material base for quality evaluation and pharmacodynamic study of Radix Angelicae pubescentis. Their purification were more than 99%. The results of this study are of great significance for exploring the effective material basis and medicinal value of the supercritical extract of Radix Angelicae pubescentis.

During the process of internal cylindrical ultrasonic-assisted electrochemical grinding (ICUAECG), both the workpiece and the conductive grinding wheel are rotating, the machining space is closed and narrow, the electrolyte is difficult to spray into the machining area, and the insulation between the workpiece and the machine bed is challenging. According to the machining characteristics of ICUAECG, the structure of a special machine tool was designed to mitigate these problems. In particular, the rotation, electrolyte supply, electric connection, and insulation modes of the workpiece clamping parts were studied, yielding a novel workpiece clamping- and rotating-device design. This structure can fully use the internal space of the hollow spindle of the machine tool, effectively reduce the external moving parts, and achieve the appropriate liquid injection angle of the electrolyte. The ultrasonic vibration system and its installation mechanism, the dressing device of the conductive grinding wheel, and the electric grinding spindle-mounting and -fixing device were analyzed in detail. Then, a special machine tool for ICUAECG was designed, the operability and feasibility of which were verified by experiments involving conductive grinding wheel dressing and ICUAECG.

Background: Flower thrips (Frankliniella intonsa, IFT) and west flower thrips (Frankliniella occidentalis, WFT) are often found together on the host plant in China. WFT is an important invasive species that seems to outcompete the native IFT. In order to clarify the interspecific competitions between the two thrips, this study measured the population development of IFT and WFT under sexual and parthenogenetic reproductive modes on two hosts (fresh lentil bean pods with/without honey and pepper plants at seedling/flowering stages) in the laboratory. Results: When reared on fresh lentil bean pods (with/without honey), WFT population size was lower in mixed species populations compared to single species populations but the presence of WFT had nor negative effect on IFT population size. These results were dependent of the reproductive mode. When honey was supplied, the ratio of female-to-male in the progeny of WFT produced under sexual reproductive mode increased significantly in the presence of IFT. On pepper seedlings, mixed populations were more favorable to the population development of IFT at the seedling stage, but more favorable to WFT at the flowering stage. Conclusions: In the early stage of WFT invasion and colonization, the emergence of flowering and honey (nectar) sources may have a positive effect on the population development of WFT.

It is important to predict the capacity related parameters of reservoir such as brittleness, total organic carbon (TOC), in-situ stress, maturity of organic carbon (Ro), and buried depth in shale gas exploration and exploitation. Among these parameters, brittleness and TOC are especially important for shale gas exploitation. The complex resistivity measurement and analysis show that the rich organic shale in southern China features low resistivity and high chargeability. These characteristics are a geophysical prerequisite for predicting the sweet spot characteristic parameters of shale, such as TOC and brittleness, with rapid developing of high resolution controlled source electromagnetic (CSEM) method prospecting which can give resistivity and chargeability distribution of underground. Based on the rich organic shale composition analysis and complex resistivity measurements in southern China, this paper analysed the presence of pyrite as an associated mineral in organic-rich shale, and examined its relationship to resistivity, chargeability, TOC content and brittleness, and the quantitative relationship between the models has been established. Therefore, this study provides a firm experimental foundation for predicting parameters of shale sweet spots with CSEM prospecting.

AIM: To analyze the effect of 532nm laser panretinal photocoagulation(PRP)combined with calcium dobesilate on fundus microcirculation and macular thickness in patients with diabetic retinopathy(DR), so as to provide experimental data for their clinical treatment. METHODS: According to the non-randomized clinical concurrent control study and voluntary principle, 174(239 eyes)DR patients were divided into observation group and control group. Both groups were treated with 532nm laser PRP, and the observation group was additionally treated with calcium dobesilate. BCVA(LogMAR)vision, clinical effect, fundus microcirculation, macular thickness and other clinical indexes were compared between the two groups before and after treatment(at 3mo after PRP). The incidence of complications during treatment was statistically analyzed. RESULTS: After treatment, BCVA in both groups were increased, and it was higher in observation group than control group. The clinical curative effect of observation group was better than that of control group(PPPPPPvs 2.6%)(χ2=0.344, P=0.557). CONCLUSION: Compared with 532nm PRP in treatment of DR, curative effect of 532nm PRP combined with calcium dobesilate is better. The latter can improve fundus microcirculation and macular thickness more significantly, with high safety.

Abstract Objective To evaluate the analgesic effect of vertebral cancellous bone infiltration anaesthesia during percutaneous vertebroplasty (PVP). Methods Patients treated with vertebral cancellous bone infiltration anaesthesia (intervention group) or local anaesthesia alone (control group) during PVP at our institution during 2016–2018 were reviewed. The visual analogue scale (VAS) score before the operation, during establishment of the puncture channel, during pressure changes in the vertebral body (e.g., when removing or inserting pushers or needle cores), during bone cement injection, immediately after the operation, and at 2 h and 1 day postoperatively were compared between the groups. The patient’s satisfaction with the operation was recorded and compared between groups. Results A total of 112 patients were enrolled (59 cases in the intervention group and 53 cases in the control group). There was no difference in the VAS score between the groups before the operation or during establishment of the intraoperative puncture channel (P > 0.05). The VAS score in the intervention group was significantly lower than that in the control group during pressure changes in the vertebral body (removal or insertion of puncture needle cores or pushers) and bone cement injection (P < 0.05). Immediately after the operation and at 2 h postoperatively, the pain in the intervention group was also significantly lower than that in the control group (P < 0.05), but there was no significant difference between the groups at 1 day postoperatively (P > 0.05). The patient satisfaction rate was 88% (52/59) in the intervention group and 67% (35/53) in the control group (P < 0.05). Conclusions Vertebral cancellous bone infiltration anaesthesia may effectively relieve intraoperative pain and improve the surgical experience of patients without affecting the clinical effect of surgery.

Transcriptional bursting has been attributed to the random switch between the off and on states of genes. Previous studies modeled gene activation as a process involving ordered multiple rate-limiting steps. Here, we aimed to understand how multi-step gene activation regulates the dynamical mRNA distribution in isogenic cell populations. We focused on both inactive and active genes for which the gene shows a longer average duration in the off and on states, respectively. We developed a method to calculate the mRNA distribution and demonstrated the unstable dynamical bimodal distribution induced by multi-step activation. The suppression of bimodality requires only a few activation steps and is achieved by triggering more cells to express the gene. In the gene-expressing cell population, multi-step gene activation modulates the transcription distribution in a bidirectional manner: the inactive gene is transcribed with enhanced heterogeneity, whereas the active gene is facilitated to generate homogeneous transcription dynamics. These regulation scenarios guide the understanding of the network structure of signaling pathways that direct gene activation.

Background: Currently there are various issues that exist in the medical institutions in China as a result of the price-setting in DRGs, which include the fact that medical institutions tend to choose patients and that the payment standard for complex cases cannot reasonably compensate the cost.Objective: The main objective is to prevent adverse selection problems in the operations of a diagnosis-related groups (DRGs) system with the game pricing model for scientific and reasonable pricing.Methods: The study proposes an improved bargaining game model over three stages, with the government and patients forming an alliance. The first stage assumes the alliance is the price maker in the Stackelberg game to maximize social welfare. Medical institutions are a price taker and decide the level of quality of medical service to maximize their revenue. A Stackelberg equilibrium solution is obtained. The second stage assumes medical institutions dominate the Stackelberg game and set an optimal service quality for maximizing their revenues. The alliance as the price taker decides the price to maximize the social welfare. Another Stackelberg equilibrium solution is achieved. The final stage establishes a Rubinstein bargaining game model to combine the Stackelberg equilibrium solutions in the first and second stage. A new equilibrium between the alliance and medical institutions is established.Results: The results show that if the price elasticity of demand increases, the ratio of cost compensation on medical institutions will increase, and the equilibrium price will increase. The equilibrium price is associated with the coefficient of patients' quality preference. The absolute risk aversion coefficient of patients affects government compensation and total social welfare.Conclusion: In a DRGs system, considering the demand elasticity and the quality preference of patients, medical service pricing can prevent an adverse selection problem. In the future, we plan to generalize these models to DRGs pricing systems with the effects of competition of medical institutions. In addition, we suggest considering the differential compensation for general hospitals and community hospitals in a DRGs system, in order to promote the goal of hierarchical diagnosis and treatment.