Integrative Analysis of miRNAs and Their Targets Involved in Ray Floret Growth in Gerbera hybrida.

MicroRNAs (miRNAs) are involved in regulating many aspects of plant growth and development at the post-transcriptional level. Gerbera (Gerbera hybrida) is an important ornamental crop. However, the role of miRNAs in the growth and development of gerbera is still unclear. In this study, we used high-throughput sequencing to analyze the expression profiles of miRNAs in ray floret during inflorescence opening. A total of 164 miRNAs were obtained, comprising 24 conserved miRNAs and 140 novel miRNAs. Ten conserved and 15 novel miRNAs were differentially expressed during ray floret growth, and 607 differentially expressed target genes of these differentially expressed miRNAs were identified using psRNATarget. We performed a comprehensive analysis of the expression profiles of the miRNAs and their targets. The changes in expression of five miRNAs (ghy-miR156, ghy-miR164, ghy-miRn24, ghy-miRn75 and ghy-miRn133) were inversely correlated with the changes in expression of their eight target genes. The miRNA cleavage sites in candidate target gene mRNAs were determined using 5'-RLM-RACE. Several miRNA-mRNA pairs were predicted to regulate ray floret growth and anthocyanin biosynthesis. In conclusion, the results of small RNA sequencing provide valuable information to reveal the mechanisms of miRNA-mediated ray floret growth and anthocyanin accumulation in gerbera.

[Microscope assisted anterior cervical discectomy and fusion for the treatment of single segment cervical spondylotic myelopathy].

OBJECTIVE: To compare the efficacy of microscope assisted anterior cervical discectomy and fusion with conventional surgical approach in the treatment of single-segment cervical spondylotic myelopathy. METHODS: The clinical data of 89 patients with single-segment cervical spondylotic myelopathy treated from March 2015 to March 2019 were retrospectively analyzed. There were 55 males and 34 females, with an average of (52.00±11.36) years old. Among the patients, 34 cases were treated with conventional anterior cervical discectomy with fusion (conventional group), including C3,4 in 3 cases, C4,5 in 10 cases, C5,6 in 15 cases, C6,7 in 6 cases; 55 cases were treated with microscopeassisted anterior cervical discectomy with fusion (microscope group), including C3,4 in 5 cases, C4,5 in 23 cases, C5,6 in 20 cases, C6,7 in 7 cases. Operative time, intraoperative blood loss, hospital stay and complications were compared between two groups. Clinical efficacy was assessed by visual analogue scale(VAS), Japanese Orthopaedics Association (JOA) scores, Oswestry Disability Index(ODI) during follow-up period (postoperative 1 week, 3 months and 12 months). RESULTS: Intraoperative blood loss and hospital stay in microscope group were less than those in conventional group (P<0.05), and operative time of conventional group was shorter than that of microscope group (P<0.05). Postoperative JOA, VAS and ODI were significantly improved in each groups (P<0.05). VAS scores of microscope group were better than that of conventional group at 1 week and 3 months after operation(P<0.05), but there was no statistically significant difference between two groups at 12 months after operation (P>0.05). JOA scores of microscope group at each postoperative follow-up were better than that of conventional group (P<0.05). ODI scores of microscope group at 3, 12 months after operation were better than that of conventional group (P<0.05). CONCLUSION: Both methods can achieve satisfactory effect in treating single-segment cervical spondylotic myelopathy. However, microscope-assisted anterior cervical discectomy and fusion has advantages of clear vision, less bleeding and fewer intraoperative complications.

Association between XRCC1 polymorphisms and glioma risk among Chinese population.

The pathogenesis of glioma remains largely unknown now. It has been suggested that the X-ray cross-complementing group 1 (XRCC1) gene may influence the capacity to repair DNA damage leading to an increased gliomas susceptibility. This study aimed to evaluate the relationship between XRCC1 polymorphisms and glioma risk. Genotypes were assessed in 368 Chinese glioma patients and 346 healthy controls. XRCC1 Arg194Trp (rs1799782), Arg280His (rs25489) and Arg399Gln (rs25487) and three additional polymorphisms were directly sequenced. The frequency of Arg280His A allele was significant lower in glioma group than in healthy controls [9.6 vs 16%, OR=0.60 (0.46-0.80), P<0.001]; the frequencies of GA or AA genotypes were different in two groups (16.6 vs 22.8%, 1.3 vs 4.7%). The frequency of Arg399Gln A allele was significant higher in glioma group than in healthy controls [38.7 vs 30.1%, OR=1.29 (1.11-1.49), P=0.001]; the frequencies of GA or AA genotypes were different in two groups (45.4 vs 38.2%, 16 vs 10.9%). This study demonstrates that the rs25489 (Arg280His) and Arg399Gln (rs25487) polymorphisms in XRCC1 gene might influence the risk of developing glioma in Chinese population.

Opportunities and challenges of sustainable agricultural development in China.

This paper introduces the concepts and aims of sustainable agriculture in China. Sustainable agricultural development comprises sustainability of agricultural production, sustainability of the rural economy, ecological and environmental sustainability within agricultural systems and sustainability of rural society. China's prime aim is to ensure current and future food security. Based on projections of China's population, its economy, societal factors and agricultural resources and inputs between 2000 and 2050, total grain supply and demand has been predicted and the state of food security analysed. Total and per capita demand for grain will increase continuously. Total demand will reach 648 Mt in 2020 and 700 Mt in 2050, while total grain yield of cultivated land will reach 470 Mt in 2010, 585 Mt in 2030 and 656 Mt in 2050. The per capita grain production will be around 360kg in the period 2000-2030 and reach 470kg in 2050. When productivities of cultivated land and other agricultural resources are all taken into consideration, China's food self-sufficiency ratio will increase from 94.4% in 2000 to 101.3% in 2030, suggesting that China will meet its future demand for food and need for food security. Despite this positive assessment, the country's sustainable agricultural development has encountered many obstacles. These include: agricultural water-use shortage; cultivated land loss; inappropriate usage of fertilizers and pesticides, and environmental degradation.