Seed Set and Natural Regeneration of Dendrocalamus membranaceus Munro after Mass and Sporadic Flowering in Yunnan,China

The flowering periods of woody bamboos, seed set, natural regeneration and death after flowering have been rarely observed and evaluated in the field. Dendrocalamus membranaceus Munro, a tropical woody bamboo mainly distributed in the Yunnan, displayed both sporadic as well as gregarious (mass) flowering and fruited from 2006 to 2013 following severe droughts. The aim of this study is to examine potential differences in seed set and natural regeneration between the two flowering patterns in natural D. membranaceus forests. We investigated and analyzed seed set, seed germination, seedling growth and mortality in both mass and sporadic flowering populations. Observations were made over a period of three years to record changes in bamboo seedling density, height and culm diameter. We observed a low natural seed set ranging from 1.76% to 7.49%, and a relatively high seed germination rate in the nursery from 59.6% to 71.0% for both types of flowering populations. Seeds germinated in 5–7 days after sowing and the germination period lasted 10–15 days. Seed set and germination rates in mass-flowering populations were significantly higher than those of sporadically flowering stands. The seedlings within sporadically flowering populations died within two years. In comparison, seedling mortality in the mass flowering population increased over two periods of observation from 64.92% to 98.89%, yet there was good seedling establishment left over, which showed mean height and mean culm diameter increasing by 1053.25% and 410.71%, respectively, in the second year of observations, and 137.10%, and 217.48%, respectively, in the third year. There are significant differences in seed set, natural regeneration ability and sustainability of bamboo populations between the mass flowering and sporadically flowering populations of D. membranaceus. Sporadic flowering populations failed to produce effective regeneration, while mass flowering populations were able to regenerate successfully. This study provides useful insights for conservation and natural forest management of D. membranaceus. We consider the merits of introducing other genetic provenances towards long-term maintenance of the stand features at sporadically flowering sites; meanwhile, the most economic option for mass flowering stands is to allow natural regeneration to take place through protecting such sites from further disturbance.     

单链莫内甜蛋白基因的合成及其植物表达载体的构建

目的:合成单链莫内甜蛋白基因,构建其植物表达载体。方法与结果:根据已报道的单链莫内甜蛋白的氨基酸序列及甜味机理,重新设计合成了全长294bp的莫内甜蛋白基因,其中单链莫内甜蛋白氨基酸序列中的Asp69(原AspA16)突变为Asn。利用DNA重组技术,将莫内甜蛋白基因克隆到植物表达载体pBl221中,构建了莫内甜蛋白基因的植物表达载体pBI221-monellin。结论:构建了莫内甜蛋白基因的植物表达载体,为转化园艺植物以改善其口感奠定了基础。     

Functional nanoparticle based on β-cyclodextrin

Aminoethylcarbamoyl-β-cyclodextrin (AEC-β-CD)-based nanoparticle is prepared by an interfacial polyaddition reaction. The nanoparticle has high β-CD content and many amino groups on the surface. The β-CD cavity of this particle forms inclusion complexes with aromatic molecules, where the uptake ability significantly depends on physicochemical factors such as hydrophobicity, ionic charge, size, and shape of guest molecules.     

水稻Dwaf1移码突变的新突变体鉴定

从一批水稻品种"中花11"组织培养苗里分离到一个矮化突变株"C6PS",它的T2代群体株高呈现3:1分离.利用该群体矮化单株与"珍汕97"."牡丹江8.,构建2个F:群体FZ(CZ).FZ(CM),两个群体中高株与矮株均呈现3:1分离,证明该性状变异为单基因控制."C6PS',表现型与已经报道的.wa叨隐性突变体"dl"相似,以DI附近标记RM430检测FZ(CZ)群体墓因型,结果显示群体表型与RM430基因型呈极显著相关(P=0.0001),将该基因初步定位于Dwarfl附近.对"C6PS',及"中花11"进行DI序列分析显示,突变株中DI墓因在其第九个外显子与第九个内含子的剪接位点上发生6个碱基的缺失,根据缺失两侧序列设计C6PS-DIL/R标记,在T:代群体该标记与表型呈现共分离,表明"C6PS"是一种新的Dwafl突变体.cDNA测序显示突变体dl基因转录产物发生26个碱基的缺失,导致移码产生终止突变,从而无法翻译出有功能的Ga蛋白,因此,它是一个Ga功能缺失突变体.叶倾斜度检测显示"C6PS",对油菜素内醋响应比野生型"中花I1"弱.     

Down-regulation of c-Myc expression inhibits the invasion of bile duct carcinoma cells

Cholangiocarcinoma is the second most common primary hepatic tumour originating from biliary tract epithelial cells with poor prognosis. Enhanced c-Myc protein expression contributes to many aspects of tumour cell biology. Although the ability of c-Myc to drive unrestricted cell proliferation and to inhibit cell differentiation had been well recognized, whether down-regulated c-Myc expression can inhibit tumour cell invasion still remains to be explored. The c-Myc ASODN (antisense oligodeoxyribonucleotide) and NSODN (nonsense oligodeoxyribonucleotide) were designed, synthesized and transfected into human QBC939 bile duct carcinoma cells using the Lipofectamine 2000 reagent. The protein expression of c-Myc was detected by Western blot. A transwell experiment was applied to evaluate the invasive capacity of the QBC939 cells. c-Myc ASODN could significantly suppress the c-Myc protein expression (P<0.05) and the invasion (P<0.01) of QBC939 cells transfected with c-Myc ASODN compared with that in the control and c-Myc NSODN-transfected group. Thus in the present study we show that down-regulation of c-Myc expression can inhibit the invasion of QBC939 cells in vitro.     

Effects of Tai Chi in Patients with Chronic Obstructive Pulmonary Disease: Preliminary Evidence

Background

Currently, several studies assessed the role of Tai Chi (TC) in management of chronic obstructive pulmonary disease, but these studies have wide variation of sample and convey inconclusive results. We therefore undertook a meta-analysis to assess the effects of TC.

Methods

A computerized search through electronic databases was performed to obtain sample studies. The primary outcomes were 6-min walking distance (6MWD) and dyspnea. Secondary outcomes included health-related quality of life and pre-bronchodilator spirometry. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) were calculated and heterogeneity was assessed with the I² test. A random-effects meta-analysis model was applied.

Results

Eight randomized controlled trials involving 544 patients met the inclusion criteria. The pooled WMDs were 34.22 m (95% CI 21.25–47.20, P<0.00001) for 6 MWD, –0.86 units (95% CI –1.44––0.28, P = 0.004) for dyspnea, 70 ml (95% CI 0.02–0.13, P = 0.01) for FEV₁, 120 ml (95% CI 0.00–0.23, P = 0.04) for FVC. TC significantly improved the Chronic Respiratory Disease Questionnaire total score, and the St George’s Respiratory Questionnaire score except impact score.

Conclusions

Findings suggest that TC may provide an effective alternative means to achieve results similar to those reported following participation in pulmonary rehabilitation programs. Further studies are needed to substantiate the preliminary findings and investigate the long-term effects of TC.     

Assessment of sugar and sugar accumulation-related gene expression profiles reveal new insight into the formation of low sugar accumulation trait in a sweet orange (Citrus sinensis) bud mutant

Molecular Biology Reports - The accumulation of soluble sugars in fleshy fruits largely determines their sweetness or taste. A spontaneous sweet orange mutant ‘Hong Anliu’ (HAL, Citrus...