‘72杨’韧皮部的构造与理化性能

将‘72杨’、杉木和毛竹的木质部进行对比试验,观察并测试‘72杨’韧皮部的解剖构造以及理化特性,为其高值化利用提供基础数据。使用场发射环境扫描电镜、X射线衍射仪、傅里叶变换红外光谱仪等设备和NREL标准对‘72杨’韧皮部的微观结构、结晶度、化学成分等物化性质进行测定与分析。研究结果表明,‘72杨’韧皮部中韧皮薄壁细胞和筛管分子占细胞总面积的(81.9±1.8)%,结构相对简单。‘72杨’韧皮部气干密度为0.358 g/cm3,绝干密度为0.321 g/cm3;而木质部的相应密度较高,分别为0.497和0.482 g/cm3;‘72杨’韧皮部结晶度仅为19.4%,比木质部低8.7%。‘72杨’韧皮部纤维素、半纤维素、木质素的含量分别为28.7%,11.1%,24.1%,均低于木质部中相应成分的含量,且木质化程度低,半纤维素以木糖为主。此外,由红外谱图发现‘72杨’韧皮部含有单宁、酚类、胼胝质等物质。‘72杨’韧皮部具有低密多孔、结构疏松、结晶度低、木质素含量低、抽提物含量高等特点。因此,‘72杨’韧皮部特别有利于机械(能耗低)或化学(抗降解屏障低)降解以及物化改性(多孔、可及性强),可提取酚类、单宁、胼胝质等物质用于工业应用,研究结果可为‘72杨’韧皮部的高值化利用提供重要的理论依据。     

黄瓜花叶病毒浙江白术分离物全基因组序列测定与分析

正白术(Atractylodes macrocephala Koidz.)为菊科(Compositae)苍术属(Atractylodes)多年生草本植物,其根茎入药具补脾健胃、燥湿利水、止汗安胎等功效,在我国广泛栽培,并以于术(浙江临安于潜)品质最佳[1]。近年来白术生产由于品种单一,长期连作等因素导致病毒病害日趋严重。据报道,黄瓜花叶病毒(Cucumber mosaic virus,CMV)~([2])、蚕豆萎蔫病毒2号(Broad bean wilt virus 2,     

Effects of antimicrobial peptides on growth,morphology of foregut villi and related genes mRNA expression in the common carp (Cyprinus carpio)

A 60‐day feeding trial was conducted to examine the effects of different levels (0, 100, 200, 400 and 600 mg/kg) of antimicrobial peptides on growth, protease activity of foregut, the morphology of foregut villi and related genes mRNA expression level in the common carp (Cyprinus carpio). The results showed that the feed of antimicrobial peptides promote common carp growth, and the optimal dosage of antimicrobial peptides is 200–333 mg/kg in the common carp feed. The protease activity of 200 and 400 mg/kg groups were significantly higher than the control and other groups (p < 0.05). The foregut villus height with 100, 200 and 400 mg/kg antimicrobial peptide groups were significantly higher than control group (p < 0.05). The crypt depth of 200 and 400 mg/kg antimicrobial peptide groups were significantly lower than control group (p < 0.05). The ratio of villus height and crypt depth of 100, 200 and 400 mg/kg antimicrobial peptide groups were significantly higher than control group (p < 0.05). The ratio with 600 mg/kg group was significantly lower than the control group (p < 0.05). The IGF‐I gene expression level of 200 mg/kg and 400 mg/kg groups were significantly higher than the control group and 600 mg/kg group (p < 0.05). The IL‐1β gene expression level of 100 mg/kg and 200 mg/kg groups were significantly higher than the control group (p < 0.05). These results indicated up‐regulation of growth and immune related genes in antimicrobial peptides fed common carp. Correlation analysis showed that IGF‐I mRNA and IL‐1β mRNA were positively correlated with SGR. IL‐1β mRNA and FCR were significantly negative correlated. It indicated that growth and immune gene common regulated the growth of the carp under antimicrobial peptides intervention. In conclusion, antimicrobial peptides can improve growth and related genes mRNA expression in the common carp. Further studies using molecular biological technique or immunologic methods are required to conclude that antimicrobial peptides are beneficial in common carp.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...     

New angiotensin-converting enzyme inhibitory peptide from Coix prolamin and its influence on the gene expression of renin-angiotensin system in vein endothelial cells

Coix seed, which is a traditional Chinese medicine, has been used to treat hypertension for thousands of years. It has been shown that Coix prolamin peptides display high levels of angiotensin I converting enzyme (ACE) inhibitory activity. Hence, we purified the ACE inhibitory peptides from Coix prolamin hydrolysates and evaluated the influence of the most potent peptide on the renin-angiotensin system (RAS) genes expression in human umbilical vein endothelial cells (HUVECs). In this study, Coix prolamin peptides were sequentially separated by ultrafiltration, ion exchange chromatography, gel filtration chromatography and RP-HPLC, while the peptide structure was analyzed by mass spectrometry. Next, in silico proteolysis, pharmacophore and molecular docking were further applied to screen and optimize the structure of peptides. Finally, a novel ACE inhibitory peptide VDMF was obtained, in which its influence on the gene expression of RAS signaling pathway in AngⅡ-injury HUVECs was evaluated by quantitative real-time PCR. VDMF significantly down-regulated ACE, AngII type 1 receptor (AT1R) and ACE2 mRNA expression in comparation with model group, while up-regulating Mas gene expression. Hence, we obtained a novel antihypertensive candidate that was derived from the Coix peptides, which could involve a multi-modulation mechanism that regulates blood pressure.     

Characteristics of Collagen from Rohu (Labeo rohita) Skin

Acid soluble collagen (ASC) and pepsin soluble collagen (PSC) were isolated from rohu skin with the yield of 64.2 and 6.8% (dry weight basis), respectively. Both collagens had glycine as the major amino acid with imino acid content of 196–202 residues/1,000 residues and were characterized as type I collagen with molecular composition of (α1)₂α2-heterotrimer. Fourier transform infrared spectra of both collagens were similar, with no shift in wavenumber of all amide bands. The T_max value of ASC and PSC was 36.40 and 35.48°C, respectively. The zero surface net charge of ASC and PSC was found at pH 5.9 and 5.3, respectively.     

晋中盆地典型耕地厚度、土壤养分空间变异

旨在探究旱作区耕地土壤耕层厚度及土壤养分空间格局与变异规律。以晋中盆地典型耕地土壤为研究对象,运用地统计学方法对耕地耕层厚度及土壤养分的空间变异进行分析,土壤养分选取有机质、pH、有效磷、缓效钾4个指标。结果表明：（1）各个指标的空间自相关性都是随着距离的增加而减小;（2）有效磷的半变异函数最优模型为高斯模型,其他指标的最优模型均为指数模型。各指标的块金系数由大到小依次为：有机质>有效磷>pH>耕层厚度>缓效钾;（3）耕层厚度、有效磷均为西北高东南低的空间格局,缓效钾为东北高西南低,有机质为西南高东北低,pH除北洸乡偏低外均偏高。地统计方法能良好地描述土壤性质的空间分布和变异特征,各土壤性质的空间变异过程中随机性与结构性并存,并且随机性均小于50%。     

玉米HD-ZIP I亚家族基因鉴定及表达分析

转录因子是植物响应逆境胁迫的重要调节因子,在其整个生长发育过程中发挥着重要的作用。HD-ZIP家族蛋白是植物中特有的一大类转录因子,包含4个亚家族(HD-ZIP I^IV),其中HD-ZIP I亚家族成员主要参与干旱、渗透压等极端环境和ABA及乙烯等激素处理的响应过程。本文采用隐马可夫模型(HMM)在玉米参考基因组中鉴定到17个HD-ZIP I亚家族成员,这些基因不均匀分布于玉米6条染色体上,与水稻的亲缘关系要近于拟南芥。玉米HDZIP I亚家族基因在玉米7种组织中表现出多种表达模式,具有明显的组织表达特异性。另外, HD-ZIP I亚家族基因对高盐、淹水及冷害等不同的逆境胁迫处理呈现出不同的响应模式及响应程度差异。5种不同激素处理后,玉米HD-ZIP I亚家族基因也表现出复杂的响应模式。这些结果为进一步解析玉米HD-ZIP I亚家族基因的生物学功能和作用机理提供了一定的参考价值。     

甜瓜黄斑病毒SYBR Green Ⅰ实时荧光定量PCR方法

为建立检测甜瓜黄斑病毒(melon yellow spot virus, MYSV)的SYBR Green Ⅰ实时荧光定量PCR(qPCR)方法。基于MYSV核衣壳蛋白基因保守序列设计qPCR特异性引物对,针对引物退火温度、引物浓度、特异性和敏感性进行系列优化。结果显示,优化后的qPCR方法最适退火温度为61.3℃,最适引物浓度为0.65μmol·L^-1,特异性强,灵敏度高,比PCR高100倍。以携带目的基因片段的重组质粒为标准品,构建的qPCR标准曲线循环阈值与模板浓度呈良好的线性关系,相关系数为0.999 7。实验样品验证表明建立的qPCR方法可用于MYSV的定量检测。     

Effect of hydrogen sulfide on myocardial fibrosis and PPARγ and NF-κB expression in rat model of diabetes

AIM: To explore the effects of hydrogen sulfide (H₂S) on the myocardial fibrosis in a rat model of diabetes and its mechanism.METHODS: Single intraperitoneal injection of streptozotocin (STZ) was utilized to establish a rat model of diabetes. Sodium hydrosulfide was used as an exogenous donor of hydrogen sulfide. Male SD rats were randomly divided into control group, STZ group, STZ+H₂S group and H₂S group. Eight weeks later, HE and VG staining methods were used to observe the collagen distribution and collagen volume fraction was measured by image analysis. The expression levels of type I collagen, PPARγ and NF-κB in the cardiac tissues were determined by Western blotting.RESULTS: Compared with control group, collagen distribution and the expression levels of type I collagen and NF-κB in the cardiac tissues were markedly increased (P<0.05), while PPARγ was significantly decreased in STZ group (P<0.05), but these indexes were reversed significantly in STZ+H₂S group (P<0.05). The expression levels of type I collagen, PPARγ and NF-κB had no significant difference between H₂S group and control group.CONCLUSION: Hydrogen sulfide attenuates cardiac fibrosis in diabetic rats, and its mechanism may be related to PPARγ-NF-κB signaling pathway.