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Lycoris species have great ornamental and medicinal values; however, their low regeneration efficiency significantly restricts their commercial production. Exogenous hormone application is an effective way to promote bulblet development, but their effect on Lycoris radiata has not been verified to date. In the present study, we examined the effect of different exogenous hormones on bulblet development in L. radiata, and found that gibberellic acid (GA) significantly inhibited, whereas paclobutrazol (PBZ), abscisic acid (ABA), and ethrel promoted bulblet development, especially PBZ, a GA biosynthesis inhibitor. Furthermore, GA reduced endogenous cytokinin (CK) content, as well as the activities of carbohydrate metabolism enzymes, including sucrose synthase (SUS) and glucose-1-phosphate adenylyltransferase (AGPase), by downregulating the expression levels of LrSUS1, LrSUS2, and genes encoding AGPase large and small subunits. This resulted in the decrease in carbohydrate accumulation in the bulblets, thus hindering their development. PBZ had the opposite effect to GA on carbohydrate metabolism; it decreased endogenous GA15 and GA24, thereby promoting bulblet development. ABA promoted endogenous auxin content and the activities of starch synthesis enzymes, especially soluble starch synthase (SSS) and granule-bound SS (GBSS), through the up-regulation of the expression levels of LrSS1, LrSS2, and LrGBSS1 genes, which could also result in the accumulation of carbohydrates in the bulblets and promote their development. In addition, ethrel application partly promoted bulblet development by promoting endogenous CK content. Although the accumulation of carbohydrates and the activity of starch enzymes were increased by ethrel treatment, we hypothesized that the effect of ethrel on regulating carbohydrate metabolism may be indirect. Our results could provide a basis for improving the propagation efficiency of L. radiata for production, as well as propose some directions for future research.

Strigolactones inhibit bud growth by negatively regulating the auxin transport without changing the auxin biosynthesis and suppressing the expression of A-ARR in buds. Strigolactones (SLs) are important phytohormones associated with regulation of shoot branching in rice. Rice shoot branching is persuasively mediated by plant hormones like auxin, cytokinins (CKs) and SLs. The interactions among these hormones were diversely investigated by many researchers but remained a subject of debate. In the present study, the removal of panicle and application of subsequent synthetic SLs were used to regulate rice bud growth on node 2 (the second node from panicle) at full heading stage. The bud growth was significantly induced after panicle removal but GR24 (synthetic SLs) application inhibited it, along with variations in endogenous hormone contents in bud. RNA samples from buds were subjected to RNA sequencing through Illumina HiSeq 2000 (RNA-seq). Comparison of transcript expression levels among three treatments, viz. (1) intact (Co), (2) removed panicle (RP) and (3) RP combined with synthetic SL GR24 (GR) revealed the involvement of numerous genes associated with hormone signal transduction. GR24 supply minimized the RP-induced enhancement of auxin early response genes, independent of ARF. CK signal transduction was also induced by RP, but type-A ARR were the only genes responding to GR without any other CK signal associated genes. Additionally, RP and GR can also modulate auxin transport and CK degradation by regulating the genes' expression involved in the biosynthesis of flavonoid, phenylpropanoid and benzoxazinoid. Contemplating the results obtained so far, it is possible to open new vistas of research to reveal the interactions among SLs, auxin and CK in controlling the shoot branching of rice.

Additional file 6: Figure S2. TIC chromatograms of standards (1 μg/ml) obtained from HPLC-MS/MS analysis. a: ZR, IAA and ABA standards at ESI + mode; b: GA3 standard at ESI – mode.

To investigate the prognostic value of microRNA-122 (miR-122) combined with acute physiology and chronic health evaluation II (APACHE II) score in patient with acute respiratory distress syndrome (ARDS), and to provide evidence for the diagnosis and treatment of ARDS.ARDS patients admitted to the Third People's Hospital of Haikou City from January 2016 to December 2018 were enrolled. The general data, serum miR-122 expression level and APACHE II score within 24 hours were collected. The patients were divided into survival group and death group according to the survival status of ARDS patients. ARDS patients were divided into low-risk group (10 scores), medium-risk group (10-20 scores) and high-risk group (20 scores) according to APACHE II score. Predictive values of miR-122 and APACHE II scores on prognosis in ARDS patients were evaluated by the receiver operating characteristic (ROC) curve. The correlation between the serum miR-122 expression and APACHE II score in patients with ARDS was calculated by Pearson correlation analysis.A total of 142 ARDS patients were selected, 94 male and 48 female; with age (56.80±11.30) years old; 55 deaths and 87 survivors; 67 of high-risk, 48 of medium-risk and 27 of low-risk. The expression of serum miR-122 and APACHE II score in the death group were significantly higher than those in the survival group [miR-122 (2Elevated serum miR-122 expression level is associated with disease severity and prognosis of ARDS patients; miR-122 combination with APACHE II score has a high evaluation value on prognosis of ARDS patients.

Apical dominance refers to the inhibition of shoot branching by the dominant shoot apex. The underlying mechanisms of apical dominance, especially in rice (Oryza sativa), remain a subject of debate. Here, we studied apical dominance in the indica rice variety ‘Yangdao 6’ and carried out a comparative proteomic analysis to analyze the different levels of expression of proteins after decapitation. A total of 38 differentially expressed proteins in nodes and buds were successfully identified by MALDI-TOF/TOF and these proteins comprised ten functional categories. Among them, several proteins in this study involved in signal transduction, transporters, and cytokinin biosynthesis may play an important role in the mechanism of apical dominance. In addition, qRT-PCR was used to quantitate the expression levels of several genes in rice nodes and buds. The results showed that after decapitation, the expression level of a CK synthesis gene, OsLOG7, was reduced in buds, however, expression levels of several CK synthesis genes, OsIPTs, were markedly increased in nodes, indicating that after panicle removal, cytokinins were synthesized in nodes and subsequently delivered to buds, which will trigger release from dormancy in buds. Expression levels of several strigolactone-related genes were reduced in nodes after decapitation, which may become a factor facilitating auxin transport out of buds to stems.

Hormones play an important role in regulating the growth of rice tiller buds. However, little is known about the hormonal changes that occur during tiller bud growth and the mechanism of hormonal regulation of tiller bud growth. Here, two rice cultivars, Yangdao 6 (Indica) and Nanjing 44 (Japonica), were used to investigate the changes in plant hormones during tiller bud growth and the mechanism that underlies the hormonal regulation of tiller bud growth. In the present study, panicles were removed after heading to stimulate the growth of dormant tiller buds located at the elongated upper internodes. At the same time, external abscisic acid (ABA), gibberellic acid (GA3) and α-naphthalene acetic acid (NAA) were applied. The results demonstrated that auxin and cytokinin (CTK) play important and different roles in the regulation of tiller bud growth. Auxin in the nodes inhibits tiller bud growth, while CTK is transferred to the tiller buds to promote growth. The inhibitory effects of GA3 and NAA on tiller bud growth are mainly due to the control of the indole-3-acetic acid (IAA) or CTK contents in plants. As opposed to auxin and CTK, the ABA contents in nodes and tiller buds remained unchanged before tiller bud growth after panicle removal. Meanwhile, external ABA application only slightly slowed the growth of the tiller buds, suggesting that ABA may not be a key regulator of tiller bud growth. These results indicate that auxin, CTK and ABA together likely play roles in the regulation of tiller bud growth.

Objective To study the risk factors for chronic obstructive pulmonary disease (COPD) in Li population in Hainan province, People’s Republic of China. Methods Li people above 40 years of age from Hainan were chosen by stratified random cluster sampling between 2012 and 2014. All participants were interviewed with a home-visiting questionnaire, and spirometry was performed on all eligible participants. Patients with airflow limitation (forced expiratory volume in 1 second [FEV1]/forced vital capacity [FVC] 20 cigarettes/day, smoking for 40 years or more, second-hand smoking, recurrent respiratory infections, and induced cough were risk factors for COPD, whereas high BMI, high education level, and presence of ventilated kitchen were protective factors. Subsequent multivariate logistic regression model further demonstrated that aging, low BMI, biomass smoke, >20 cigarettes/day, and recurrent respiratory tract infections were high-risk factors for COPD in the Li population. Conclusion The incidence of COPD has a strong correlation with age, BMI, biomass smoke, >20 cigarettes/day, and recurrent respiratory infections, suggesting they were high-risk factors for COPD in Li population.

Yipeng Ding,1,* Danlei Yang,2,3,* Long Zhou,4 Junxu Xu,5 Yu Chen,5 Ping He,1 Jinjian Yao,1 Jiannan Chen,1 Huan Niu,1 Pei Sun,1 Tianbo Jin4 1Department of Emergency, People’s Hospital of Hainan Province, Haikou, Hainan, 2Department of Respiratory and Critical Care Medicine, Tongji Hospital, Key Laboratory of Pulmonary Diseases of Health Ministry, Tongji Medical College, 3Department of Science and Technology, Huazhong University, Wuhan, 4School of Life Sciences, Northwest University, Xi’an, 5Department of Respiration Emergency, The Third People’s Hospital of Haikou, Haikou, Hainan, People’s Republic of China *These authors contributed equally tothis work Background: It is known that the contribution of risk alleles to chronic obstructive pulmonary disease (COPD) may vary between populations. Further, previous studies involving various ethnic groups have revealed associations between COPD and genetic polymorphisms in families with sequence similarity 13, member A (FAM13A), micro-RNA 2054 (MIR2054), SET domain containing protein 7 (SETD7), ring finger protein 150 (RNF150), hedgehog interacting protein (HHIP), and vascular endothelial growth factor A (VEGFA). Our objective was to explore the association between these gene polymorphism and COPD in members of Chinese Li minority population.Materials and methods: The Chinese Li population case–control study was conducted to assess genetic associations with COPD risk. Seven single nucleotide polymorphisms (SNPs) located on chromosome 4, including FAM13A, MIR2054, SETD7, RNF150, and HHIP, and nine SNPs in the VEGFA gene were genotyped among 234 cases and 240 controls using Sequenom Mass-ARRAY® platform. Linkage disequilibrium (LD) analysis was performed using Haploview software and the associations of the SNP frequencies with COPD were analyzed using chi-square (χ2) tests, genetic models analysis, and haplotype analysis.Results: By χ2 we found the minor allele “G” of rs17050782 was with increased COPD risk in allele model. In genetic models, we found the minor allele of rs7671167 (P=0.028 by dominant model) and rs17050782 (P=0.008 by recessive model) was associated with the increased risk of COPD disease. Likewise, an increased risk of developing COPD was associated with the “GGCGC” haplotype of VEGFA (odds ratio =1.48, 95% confidence interval =1.02–2.12, P=0.037).Conclusion: Our results were the first time to reveal that SNPs from FAM13A (rs7671167), SETD7 (rs17050782), and a haplotype of VEGFA (“GGCGC”) are potential susceptibility loci associated with increased COPD risk in Chinese Li minority population. Keywords: chronic obstructive pulmonary disease, case–control study, single nucleotide polymorphism, Chinese Li minority population

Nitrogen availability and cytokinin could promote shoot branching in rice, whereas auxin and strigolactone inhibited it. The interaction between nitrogen availability and the three hormones is discussed. Rice shoot branching is strongly affected by nitrogen availability and the plant hormones auxin, cytokinin, and strigolactone; however, the interaction of them in the regulation of rice shoot branching remains a subject of debate. In the present study, nitrogen and the three hormones were used to regulate rice tiller bud growth in the indica rice variety Yangdao 6. Both nitrogen and CK promoted shoot branching in rice, whereas auxin and SL inhibited it. We used HPLC to determine the amounts of endogenous IAA and CK, and we used quantitative real-time PCR analysis to quantify the expression levels of several genes. Nitrogen enhanced the amount of CK by promoting the expression levels of OsIPTs in nodes. In addition, both nitrogen and CK downregulated the expression of genes related to SL synthesis in root and nodes, implying that the inhibition of SL synthesis by nitrogen may occur at least partially through the CK pathway. SL did not significantly reduce the amount of CK or the expression levels of OsIPT genes, but it did significantly reduce the amount of auxin and the auxin transport capacity in nodes. Auxin itself inhibited CK synthesis and promoted SL synthesis in nodes rather than in roots. Furthermore, we found that CK and SL quickly reduced and increased the expression of FC1 in buds, respectively, implying that FC1 might be a common target for the CK and SL pathways. Nitrogen and auxin delayed expression change patterns of FC1, potentially by changing the downstream signals for CK and SL.

Sixty-three proteins were identified to be differentially accumulated due to iron deficiency in shoot and root. The importance of these proteins alterations on shoot physiology is discussed. Iron (Fe) is an essential micronutrient for plant growth and its accumulation affects the quality of edible plant organs. To investigate the adaptive mechanism of a Chinese rice variety grown under iron deficiency, proteins differentially accumulated in leaves and roots of Yangdao 6, an indica cultivar, under Fe deficiency growth condition, were profiled using a two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF/MS). The accumulations of seventy-three proteins were detected to be increased or decreased upon iron deficiency, and sixty-three of them were successfully identified. Among the sixty-three proteins, a total of forty proteins were identified in rice leaves, and twenty-three proteins were in roots. Most of these proteins are involved in photosynthesis, C metabolism, oxidative stress, Adenosine triphosphate synthesis, cell growth or signal transduction. The results provide a comprehensive way to understand, at the level of proteins, the adaptive mechanism used by rice shoots and roots under iron deficiency.

Yipeng Ding,1,* Junxu Xu,2,* Jinjian Yao,1 Yu Chen,2 Ping He,1 Yanhong Ouyang,1 Huan Niu,1 Zhongjie Tian,1 Pei Sun1 1Department of Emergency, People’s Hospital of Hainan Province, 2Department of Respiratory, The Third People’s Hospital of Haikou, Haikou, Hainan, People’s Republic of China *These authors contributed equally tothis work Objective: To study the risk factors for chronic obstructive pulmonary disease (COPD) in Li population in Hainan province, People’s Republic of China.Methods: Li people above 40 years of age from Hainan were chosen by stratified random cluster sampling between 2012 and 2014. All participants were interviewed with a home-visiting questionnaire, and spirometry was performed on all eligible participants. Patients with airflow limitation (forced expiratory volume in 1 second [FEV1]/forced vital capacity [FVC] 20 cigarettes/day, smoking for 40 years or more, second-hand smoking, recurrent respiratory infections, and induced cough were risk factors for COPD, whereas high BMI, high education level, and presence of ventilated kitchen were protective factors. Subsequent multivariate logistic regression model further demonstrated that aging, low BMI, biomass smoke, >20 cigarettes/day, and recurrent respiratory tract infections were high-risk factors for COPD in the Li population.Conclusion: The incidence of COPD has a strong correlation with age, BMI, biomass smoke, >20 cigarettes/day, and recurrent respiratory infections, suggesting they were high-risk factors for COPD in Li population. Keywords: chronic obstructive pulmonary disease, epidemiology, survey, Li population