贵州省野生皂荚种实表型性状多样性分析

为深入了解贵州省野生皂荚(Gleditsia sinensis)荚果表型性状的遗传多样性及其变异类型,为皂荚的遗传改良、种质鉴定、亲本选择以及品种培育奠定理论基础。该研究以贵州省7个野生皂荚群体70个个体为研究对象,采用方差分析、主成分分析、相关性分析及多性状综合评价等方法对皂荚群体的10个种实表型性状进行系统分析和综合评价。结果显示：(1)所测皂荚的表型性状差异在群体内均达到极显著水平(P＜0.01);在群体间,除每荚粒数、种子宽、种子长宽积以及种子长宽比之外,其余表型性状的差异均达极显著水平(P＜0.01)。(2)7个居群野生皂荚各性状平均变异系数为21.16%,其中凯里市(P4)居群的变异系数最高(24.44%);居群间荚果的变异(29.22%)高于种子的变异(11.04%),且变异主要来自于群体内。(3)相关分析显示,皂荚种实各性状之间存在不同程度的关联性;主成分分析显示,前4个主成分(皂荚种子大小、单个荚果出籽数量、种子形态指数因子、与荚果长和种子厚相关的因子)的累积贡献率达69.783%,可基本反映皂荚表型性状的大部分信息;以10个种实性状对皂荚野生群体进行综合评价发现,来自于惠水县(P7)群体的皂荚种实性状综合评价最高。研究表明,贵州省野生皂荚在群体间及群体内具有丰富的表型变异,且群体内的变异大于群体间的变异,变异主要来自于群体内。     

Corn porous starch: preparation, characterization and adsorption property

This study was carried out to develop a new type of modified starch based on α-amylase and glucoamylase. The structural and chemical characteristics of the porous starch were determined by Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The potential application of the porous starch as an adsorbent was evaluated using methyl violet as an adsorbed model. The adsorption capacity was optimized by investigating the reaction factors, including the mass ratio of α-amylase to glucoamylase (m_α-amylase/m_glucoamylase), the mass ratio of total amount of enzymes to starch (m_enzyme/m_St), the ratio of liquid volume to starch mass (VH₂O/mSt), pH value of the reaction solution, enzymatic reaction temperature, and enzymatic reaction time. The hydrolysis ratio of each sample was also determined to investigate the effect of different reaction conditions on the hydrolysis degree. The results suggest that the porous starch has a more excellent adsorption capacity than the native starch, and may be expected to have wide potential applications in many fields.     

荷斯坦牛BoLA-DRA基因SNPs筛选及生物信息学分析

为了探讨BoLA-DRA基因多态性,本研究利用DNA混合池扩增产物直接测序的方法对荷斯坦牛BoLA-DRA基因编码区SNPs进行筛选,并利用生物信息学软件预测该基因m RNA二级结构。结果表明:荷斯坦牛BoLA-DRA基因编码区共有4个SNPs (exon2-A82T,exon2-G116A,exon2-C197T,exon2-C233A)。生物信息学预测结果显示,exon2-A82T、exon2-G116A和exon2-C233A增大了m RNA二级结构的稳定性,而exon2-C197T降低了mRNA二级结构的稳定性。本研究结果可为荷斯坦牛抗病和抗逆性能研究积累更多的分子遗传学数据,并为经济性状相关基因筛选提供理论依据。     

Functional Characterization of <Emphasis Type="Italic">Vibrio alginolyticus</Emphasis> Twin-Arginine Translocation System: Its Roles in Biofilm Formation,Extracellular Protease Activity,and Virulence Towards Fish

The bacterial twin-arginine translocation (Tat) system contributes to translocate folded proteins and plays pleiotropic roles in growth, motility, and the secretion of some virulent factors. In this study, the authors identified the Tat gene cluster in fish pathogen Vibrio alginolyticus and explored its roles in pathogenesis toward fish. Vibrio alginolyticus Tat mutants showed growth deficiency in TMAO medium, while the complement strain restored the ability to grow in the medium, demonstrating the conservative function of the Tat system in translocation of redox enzymes or cofactors in this bacterium. In V. alginolyticus, deletion of the tatABC genes led to a drastic decrease in biofilm biogenesis. Interestingly, the secretion of extracellular protease Asp, an established exotoxin of the bacterium, was significantly decreased in the TatC mutant, suggesting that TatC might play a part in the production of virulence factors in the bacterium. Furthermore, the Tat mutants displayed attenuated virulence toward the fish model and EPC cells. These findings suggest that the Tat secretion related to the extracellular protease activity as well as virulence in V. alginolyticus provided new insights into the pathogenesis of vibriosis in fish.     

Eyes are windows to the Chinese soul: evidence from the detection of real and fake smiles

How do people interpret the meaning of a smile? Previous studies with Westerners have found that both the eyes and the mouth are crucial in identifying and interpreting smiles, yet less is known about Easterners. Here we reported that when asking the Chinese to judge the Duchenne and non-Duchenne smiles as either real or fake, their accuracy and sensitivity were negatively correlated with their individualism scores but positively correlated with their collectivism scores. However, such correlations were found only for participants who stated the eyes to be the most useful references, but not for those who favored the mouth. Moreover, participants who favored the eyes were more accurate and sensitive than those who favored the mouth. Our results thus indicate that Chinese who follow the typical Eastern decoding process of using the eyes as diagnostic cues to identify and interpret others'' facial expressions and social intentions, are particularly accurate and sensitive, the more they self-report greater collectivistic and lower individualistic values.     

The caspase-8 shRNA-modified mesenchymal stem cells improve the function of infarcted heart

The beneficial effects of mesenchymal stem cells (MSCs) in cardiac cell therapy are greatly limited due to poor survival after transplantation into ischemic hearts. Here, we investigated whether caspase 8 small hairpin RNA (shRNA) modification enhance human MSCs (hMSCs) survival and improve infarcted heart function. Recombinant adenovirus encoding pre-miRNA-155-designed caspase 8 shRNA was prepared to inhibit caspase 8 expression in hMSCs. The effect of caspase 8 shRNA modification on protecting hMSCs from apoptosis under the conditions of serum deprivation and hypoxia was tested by Annexin V/PI staining and caspase 8 activity assay. The caspase 8 shRNA-modified and superparamagnetic iron oxide (SPIO)-labeled hMSCs were injected into the border zone of the infarcted region of rat heart. Echocardiography and Masson trichrome staining were performed to assess heart function and cardiac fibrosis. Our results showed that adenovirus-mediated caspase 8 shRNA could efficiently inhibit caspase 8 expression in hMSCs. Knock-down of caspase 8 expression lead to inhibition of hMSCs apoptosis, reduction of caspase 8 activity and up-regulations of HGF, IGF-1 and Bcl-2. Transplantation of caspase 8 shRNA-modified hMSCs could significantly improve infracted heart function, attenuate cardiac fibrosis. Consistently, the rate of cardiomyocyte apoptosis and caspase 8 activity were significantly decreased, and the survival rate of transplanted hMSCs was markedly elevated in the myocardium receiving caspase 8 shRNA-modified hMSCs transplantation. Together, our findings implicated the therapeutic potential of caspase 8 shRNA-modified hMSCs in improving the infarcted heart function.     

Peripheral blood monocytes from the decompensated liver cirrhosis could migrate into nude mouse liver with human hepatocyte-markers expression

Adult stem cells provide a promising alternative for the treatment of decompensated liver cirrhosis. Our previous study showed that peripheral blood monocytes (PBMCs) from decompensated liver cirrhosis could differentiate into hepatocyte-like cells in vitro. We here aimed to investigate the differential potential of the PBMCs under liver environment. PBMCs were isolated from one cirrhotic patient, who was mobilized by the recombinant human granulocyte colony stimulating factor for consecutive 3 days, and then PBMCs were transplanted into nude mice by tail vein after labeled with PKH26-GL. The location of the transplanted PBMCs was identified by PKH26-GL staining and PRINS for human SRY gene. The expressions of human hepatocyte-markers were detected by immunohistochemistry, RT-PCR, and Western blot analysis. Our results demonstrated that PBMCs from decompensated liver cirrhosis could migrate into the liver of nude mice with human hepatocyte-markers expression, indicating that autologous PBMCs transplantation might be one alternative therapy for the decompensated liver cirrhosis.     

Growth arrest-specific gene 1 is downregulated and inhibits tumor growth in gastric cancer

Gastric cancer is one of the leading causes of malignancy-related mortality in the world, and malignant growth is a crucial characteristic in gastric cancer. In our previous study, we found that growth arrest-specific gene?1 (GAS1) suppression was involved in making gastric cancer cells multidrug-resistant by protecting them from drug-induced apoptosis. In the present study, we investigated the potential role of GAS1 in the growth and proliferation of gastric cancer. We demonstrated that GAS1 expression was decreased in gastric cancer, and patients without GAS1 expression showed shorter survival times than those with GAS1 expression. Both gain-of-function (by overexpression of GAS1) and loss-of-function (by GAS1-specific small interfering RNA knockdown) studies showed that increased GAS1 expression significantly reduced the colony-forming ability of gastric cancer cells in?vitro and reduced cell growth in?vivo, whereas decreased GAS1 expression had the opposite effects. Moreover, upregulation of GAS1 induced cell apoptosis, and downregulation of GAS1 inhibited apoptosis. Furthermore, we demonstrated that GAS1 could induce gastric cancer cell apoptosis, at least in part through modulating the Bcl-2/Bax ratio and the activity of caspase-3. Taken together, our results strongly indicate that GAS1 expression was decreased in gastric cancer and was predictive of a poor prognosis. Restoration of GAS1 expression inhibited cell growth and promoted apoptosis of gastric cancer cells, at least in part through modulating the Bcl-2/Bax ratio and activating caspase-3, suggesting that GAS1 might be used as a novel therapeutic candidate for gastric cancer.     

农业激光生物效应的可比性实验与数理统计

本文根据数理统计的原理和方法,初步讨论了农业激光生物效应可比性实验的问题。