Effect of sowing date and plant density on the cell morphology of hemp (Cannabis sativa L.)

A range of papers report a major effect of agronomic procedures on the growth, biomass, fibre yield and fibre quality of hemp. The aim of this paper is to examine the influence of sowing date, seed density and year on histological characteristics of hemp (size of the different layers in the cross section of the stem, area of primary fibre cells and their cell lumen, size of fibre cell wall). It was realised that a higher seed density resulted in a reduction of almost all layers in the cross section of the stem. A similar effect was caused by the drought 1998, whereas the sowing date had almost no influence on the size of the various layers. The area of primary fibre cells was smaller in 1998. Sowing date and seed density did not affect the fibre cell area and area of cell lumen in the way mentioned above during the 2 years of the trial. During this period the size of cell wall was mainly determined by climatic conditions. Higher elongation and higher tensile strength of hemp planted at higher seed density is probably caused by differences in primary cell morphology.     

Dorsal and ventral stimuli in cell-material interactions: effect on cell morphology

Cells behave differently between bidimensional (2D) and tridimensional (3D) environments. While most of the in vitro cultures are 2D, most of the in vivo extracellular matrices are 3D, which encourages the development of more relevant culture conditions, seeking to provide more physiological models for biomedicine (e.g., cancer, drug discovery and tissue engineering) and further insights into any dimension-dependent biological mechanism. In this study, cells were cultured between two protein coated surfaces (sandwich-like culture). Cells used both dorsal and ventral receptors to adhere and spread, undergoing morphological changes with respect to the 2D control. Combinations of fibronectin and bovine serum albumin on the dorsal and ventral sides led to different cell morphologies, which were quantified from bright field images by calculating the spreading area and circularity. Although the mechanism underlying these differences remains to be clarified, excitation of dorsal receptors by anchorage to extracellular proteins plays a key role on cell behavior. This approach--sandwich-like culture--becomes therefore a versatile method to study cell adhesion in well-defined conditions in a quasi 3D environment.     

Effect of surface-active agent on morphology and properties of electrospun PVA nanofibres

After the addition of a surface-active agent, sodium dodecyl benzene sulfonate (SDBS), electrospun polyvinyl alcohol (PVA) nanofibres showed a significant enhancement in the mechanical properties, such as improved tensile strength and elongation at break. The improved crystallinity and strong intermolecular hydrogen bonds between the molecules of SDBS and PVA were the two main factors that improved the mechanical properties. In addition, a sharp decrease in surface tension of PVA solution with the addition of SDBS was observed, and the protruding droplet at the tip of needle diminished in the electrospinning process.     

Effects of PLGA nanofibrous scaffolds structure on nerve cell directional proliferation and morphology

Electrospinning has been recognized as an efficient technique for the fabrication of neural tissue engineering scaffolds. Many approaches have been developed on material optimization, electrospinning techniques, and physical properties of scaffolds to produce a suitable scaffold for tissue engineering aspects. In this study, structural properties of scaffolds were promoted by controlling the speed of fiber collection without any post-processing. PLGA scaffolds, in two significantly different solution concentrations, were fabricated by the electrospinning process to produce scaffolds with the optimum nerve cell growth in a desired direction. The minimum, intermediate and maximum rate of fiber collection (0.4, 2.4, 4.8 m/s) formed Random, Aligned and Drown-aligned fibers, with various porosities and hydrophilicities. The scaffolds were characterized by fiber diameter, porosity, water contact angle and morphology. Human nerve cells were cultured on fiber substrates for seven days to study the effects of different scaffold structures on cell morphology and proliferation, simultaneously. The results of MTT assay, the morphology of cells and scaffold characterization recommend that the best structure to promote cell direction, morphology and proliferation is accessible in an optimized hydrophilicity and porosity of scaffolds, which was obtained at the collector linear speed of 2.4 m/s.     

Effect of hot-stretching on morphology and mechanical properties of electrospun PMIA nanofibers

Well-aligned PMIA nanofiber mats were fabricated by electrospinning and then hot-stretching along the fiber axis was used to improve the mechanical properties of nanofibers in this paper. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and Differential scanning calorimetry (DSC) were used to characterize the morphology and properties of nanofibers. The results showed that the nanofibers became thinner and better alignment than the as-spun nanofibers after hotstretching, and the average diameter of the nanofibers decreased with the increasing of the tensile force. In the same time, hotstretching improved the crystallinity and T _g of the as-spun PMIA nanofibers. The tensile strength and modulus of the hotstretched nanofiber mats peaked at ca.50 % and ca.196 % respectively at the tensile force of 12 N compared with the as-spun nanofiber mats.     

硅对甘蔗黑穗病菌的体外抑菌效果研究

由鞭黑粉菌（Sporisorium scitamineum）引起的黑穗病是甘蔗（Saccharum spp.）生产上最重要的真菌病害。硅是植物生长过程中的有益矿质元素,能够提高植物对生物和非生物胁迫的抗性。目前,关于外源硅对甘蔗黑穗病菌的体外抑菌作用尚未见报道。本研究以硅酸钠（sodium silicate, Na₂SiO₃）和硅酸钾（potassium silicate, K₂SiO₃）处理甘蔗黑穗病菌,观察黑穗病菌的孢子萌发、菌落直径和菌丝生长情况,评价不同硅剂和pH对甘蔗黑穗病菌的体外抑菌效果。结果显示,0.5~20.0 mmol/L Na₂SiO₃和K₂SiO₃均完全抑制甘蔗黑穗病菌的孢子萌发,但1.0 mmol/L Na₂SiO₃促进甘蔗黑穗病菌菌落和菌丝的生长,10.0、20.0 mmol/L Na₂SiO₃和K₂SiO₃则显著抑制菌落和菌丝的生长,表明Na₂SiO₃和K₂SiO₃均会影响甘蔗黑穗病菌的生长,高浓度Na₂SiO₃和K₂SiO₃的抑菌效果明显。在不同pH条件下,低pH（5.87~10.86）处理下的甘蔗黑穗病菌孢子有萌发,但其萌发率随着pH的增大逐渐降低,高pH（≥10.96）完全抑制孢子萌发,此外,pH为9.40和11.57对菌落直径的抑制效果明显。调整pH为6.0的低浓度Na₂SiO₃（0~5.0 mmol/L）和K₂SiO₃（0~3.5 mmol/L）对孢子萌发影响小,但pH为6.0的高浓度Na₂SiO₃（7.0~20.0 mmol/L）和K₂SiO₃（5.0~20.0 mmol/L）显著抑制孢子萌发,表明相同pH水平下的K₂SiO₃比Na₂SiO₃及其对应pH处理对甘蔗黑穗病菌孢子萌发的抑制作用更为明显。研究结果为外源硅在甘蔗抗黑穗病的药效试验和防治机理研究提供参考。     

纳豆激酶的分离纯化及体外溶栓特性研究

通过硫酸铵分步沉淀和Sephadex G-100凝胶过滤层析,分离纯化纳豆激酶,并用SDS-PAGE和PAGE电泳检测纯化效果,体外溶栓试验检测纳豆激酶的溶栓特性。SDS-PAGE显示纳豆激酶为单一条带,分子量为33kDa,而PAGE至少有3个具有纤溶活性的区域,表明纳豆激酶可能由几种同工酶组成,体外溶栓结果表明:与蚓激酶相比,纳豆激酶具有较强的的体外溶栓和抗凝作用,并有一定的溶血作用。     

Effect of fermentation on sorghum protein fractions and in vitro protein digestibility

Changes in pH, titratable acidity, total soluble solids and proteins ofDabar sorghum (Sorghum bicolor (Linn) Moench.) during naturalfermentation at 37 ^°C for up to 36 h were monitored. The pH ofthe fermenting material decreased sharply with a concomitant increase in the titratable acidity. Total soluble solids increased with progressivefermentation time. The crude protein and non-protein nitrogen slightlyincreased during the last stages of fermentation. The in vitroprotein digestibility markedly increased as a result of fermentation.The globulin plus albumin fractions increased significantly (p 0.05)during the first 8 h of fermentation. Kaffirin fraction decreasedduring the first 8 h of fermentation but increased sharply as fermentationprogressed. Cross-linked kaffirins fluctuated during the fermentationprocess. Glutelin like protein, which was the minor fraction, trueglutelins, the second most abundant fraction, together with non-extractableproteins fluctuated during the fermentation process.     

茶多酚体内外抗流感病毒作用研究

研究了没食子儿茶素(Gallocatechin, GC)、表儿茶素(Epicatechin, EC)、表没食子儿茶素(Epigallocatechin, EGC)、表儿茶素没食子酸酯(Epicatechin gallate, ECG)、表没食子儿茶素没食子酸酯(Epigallocatechin gallate, EGCG)、原儿茶醛(Protocatechuic aldehyde, PAD)、原儿茶酸(Protocatechuic acid, PA)共7种茶多酚类物质在MDCK细胞中的抑制流感病毒活性。结果表明,EGCG和ECG具有显著的抑制病毒作用,对感染H₅N₁、H₁N₁和H₉N₂ 3种亚型流感病毒的MDCK细胞50%保护率浓度(EC₅₀)分别在0.04~0.11 mmol/L和0.05~0.07 mmol/L范围,其保护效果均优于阳性对照药利巴韦林（EC₅₀：0.41~0.53 mmol/L）。7种茶多酚类物质对流感病毒神经氨酸酶（NA）均有不同程度的抑制作用,EGCG和ECG对H₅N₁、H₁N₁和H₉N₂ 3种亚型流感病毒NA活性抑制浓度（IC₅₀）分别在0.03~0.14 mmol/L和0.34~0.69 mmol/L范围。茶多酚对NA的抑制活性大小与其细胞中对病毒的抑制作用基本一致,表明对NA的抑制可能是其抗流感病毒机制。本文还研究了茶多酚含量为85%的苦茶(C. assamica var. Kucha)提取物对感染流感病毒小鼠的肺炎抑制效果,结果显示,1 000 mg/(kg·d)苦茶提取物对感染H₉N₂亚型流感病毒BALB/c鼠肺炎有显著抑制作用(P﹤0.05),肺指数抑制率达37%。     

Effect of solution and apparatus parameters on the morphology and size of electrosprayed PLGA microparticles

Because of a number of facilities, the Electrospray (ES) method is gaining ever-increasing popularity among researchers for producing nano-to-micron-sized particles. Microparticles (MPs) of poly lactic-co-glycolic acid (PLGA) were prepared by using the ES technique. The influence of both solution and apparatus parameters on the morphology, size, size distribution, and uniformity of produced MPs were investigated. Results of SEM images and calculations revealed that polymer concentration is a critical parameter in the ES system. In a semi-dilute moderately entangled regime, chain entanglement can easily occur. Solution flow rate is a key factor among apparatus parameters. Vapour pressure is a key parameter affecting MP morphology. The size of the particles tended to reduce with an increase in voltage. The needle gauge did not have an important impact on particle size. The role of the electric field changed at different collecting distances. Using a saturated combination of EtOH/PVA is an acceptable collecting medium for PLGA MPs. It is possible to produce uniform and spherical MPs by using chloroform as a solvent. However, a reduction in particle size is achievable by using a solvent of chloroform/DMF (90/10 w/w).     

Effect of Urea/NaOH aqueous system on morphology and properties of cotton fabric

This paper was focused on comparing the effect of urea/NaOH aqueous system with that of single urea or NaOH treating system on cotton fabric morphology and properties. Optical microscopy (OM), scanning electron micrograph (SEM), Fourier transform infrared spectroscopy (FT-IR), and wide X-ray diffraction (WAXD) were used to study cotton fabric morphology and properties before and after treatment by urea/NaOH, single urea, and single NaOH treating systems. Results showed that the cotton fabric treated by urea/NaOH aqueous system had better dyeability than the samples untreated and treated by single urea or single NaOH treating systems. Obvious differences were observed in appearance and morphology of cotton fabrics before and after treatment by urea/NaOH aqueous system. The composition and the structure of urea/NaOH treated cotton fiber had no distinct changes, only except the reduced hydrogen bonding between cellulosic macromolecules. Tensile strength and elongation at break of cotton fabric showed a slight decrease after treatment by urea/NaOH system. In addition, shrinkage of area and weight reduction of urea/NaOH treated samples were higher than those of the samples untreated and treated by single urea or single NaOH treating system.     

磷对花生根系形态特征的影响

为探讨花生合理施磷量,采用大田无底圆桶的桶栽试验,研究不同磷水平对花育22号(大花生)和花育20号(小花生)根系形态和产量的影响。2015和2016两年结果表明,磷对花生植株根系长度影响显著,在磷肥用量0~135kg/hm^2范围内,根系总长度随施磷量的增加而增加;磷肥用量为180kg/hm^2时,根系总长度不再增加或增加甚少;根系总表面积也基本随施磷量的增加而增加,施磷处理的根系总表面积比对照(不施磷)增加20.0%以上;根系总体积两品种两年大多数处理高于对照。将根系按照根的粗细划分为细、中、粗三类,发现施磷可显著增加细根长、细根表面积和体积,而粗度中等和较粗的根增加量较小,甚至出现负值。两品种施磷处理的主茎高、侧枝长、分枝数、单株结果数和百果重提高1.3%~20.6%,其增加的幅度远低于磷对根系形态的促进效应。在0~90kg/hm^2范围内,施磷增产效果显著,超过90kg/hm^2后产量增加较少,甚至略有下降。小花生产量对磷肥的响应比大花生敏感。花生产量与根系长度相关性可达显著或极显著水平,而根系表面积和体积与产量的关系因品种而不同。形态上细分根的类型将可能更有利于花生高产栽培。     

Effect of fertilizers on human environment in Bulgaria

Data are quoted in the article from the studies on the effect of fertilizer use in the recent 10 years on the quality of drinking water. Results are also given from some experiments on the overcoming of nitrate accumulation in plant tissue of lettuce and forage maize. There has been established that balanced nutrition decreased nitrate content in the plants.

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Zusammenfassung In diesem Beitrag werden die Ergebnisse der Untersuchungen über den Einfluß der in den letzen 10 Jahren aufgewendeten Dünger auf die Qualität des Trinkwassers wiedergegeben. Außerdem werden Versuchsergebnisse über die Vermeidung der Nitratakkumulation in Salat und Silomais angeführt. Es wird festgestellt, daß eine ausgewogene Düngung einen niedrigen Nitratgehalt in den Pflanzen bewirkt.

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Résumé L'article fournit des données sur l'influence de la fumure sur la qualité de l'eau potable durant une période de 10 ans.Il présente également les données d'experimentations enterprises en vue de surmonter l'accumulation des nitrates dans les tissus des laitues et du mais-fourrage. On a constaté que la diminution de l'accumulation des nitrates se realise en équilibrant la nutrition des plantes.

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Paper read on the Expert Panel Effects of Intensive Fertilizer use on the Human Environment, 25–28 January, 1972, FAO, Rome     

长生牌鹿茸片对小鼠免疫功能的影响

目的研究长生牌鹿茸片对小鼠免疫功能的影响。方法厂家推荐长生牌鹿茸片成人每日摄入量为1.0g/60kg BW,以推荐剂量的5、10、30倍(0.0833、0.1667、0.5000 g/kg)给药,测定受试物对小鼠体重增长、脏器/体重比值、Con A诱导的小鼠淋巴细胞转化能力、抗体生成细胞数、小鼠半数溶血值、小鼠单核-巨噬细胞碳廓清能力、NK细胞活性的影响。结果与阴性对照组比较,中高剂量组受试物能提高小鼠单核-巨噬细胞碳廓清能力。结论长生牌鹿茸片具有增强免疫力的作用。     

抑菌剂抑菌效果及对马铃薯试管苗生长发育的影响

为降低马铃薯组培污染,试验采用多菌灵、盐酸万古霉素、制霉菌素、益培隆和冰片5种抑菌剂,开展不同浓度处理对青霉菌、黑曲霉、细菌抑制效果比较及其对马铃薯试管苗生长发育的影响试验。结果表明,冰片与益培隆浓度分别达20和50 mg/L时,对青霉菌的抑制率达100.0%;冰片、益培隆和制霉菌素浓度分别达50,80和80 mg/L时,对黑曲霉的抑制率达100.0%;冰片、益培隆和盐酸万古霉素浓度分别达20,50和80 mg/L时,对细菌的抑制率达100.0%;5种抑菌剂浓度为20 mg/L时,对试管苗生长发育及成活率均无任何影响,当浓度增大到80 mg/L时,对试管苗生长发育均有抑制作用。     

二倍体马铃薯试管苗的培养及对叶肉原生质体融合的影响

以35份二倍体马铃薯试管苗为试验材料,对二倍体马铃薯试管苗培养的影响因素进行研究,目的是使试管苗的叶片增大,叶面积增加,并有利于进行叶肉原生质体的融合。结果表明:含有AgNO3的培养基(MS+0.5 mg/L NAA+1 mg/L AgNO3)适合22份供试二倍体马铃薯试管苗的培养;添加AgNO3比不添加AgNO3的试管苗的叶片明显增大,叶面积显著增加,添加2%蔗糖和2 mg/L AgNO3的培养基的试管苗叶面积最大;以二倍体野生种S.chacoense和二倍体材料DY4-5-10为亲本进行电融合,以添加2%蔗糖和1 mg/L AgNO3的培养基培养其试管苗,获得的融合产物可再生出完整植株,该培养基适合用于分离原生质体的二倍体马铃薯试管苗的培养。     

Effect of Grain Structure and Cooking on Sorghum and Maize in vitro Protein Digestibility

Uncooked and cooked sorghum showed improvement in in vitro protein digestibility as the structural complexity of the sample reduced from whole grain flour through endosperm flour to protein body-enriched samples. This was not the case for maize. Cooking reduced protein digestibility of sorghum but not maize. Treating cooked sorghum and maize whole grain and endosperm flours with alpha -amylase to reduce sample complexity before in vitro pepsin digestion slightly improved protein digestibility. The reduction in sorghum protein digestibility on cooking was not related to the total polyphenol content of samples. Pericarp components, germ, endosperm cell walls, and gelatinised starch were identified as possible factors limiting sorghum protein digestibility. Electrophoresis of uncooked and cooked protein-body-enriched samples of sorghum and maize, and prolamin fractions of sorghum under non-reducing conditions showed oligomeric proteins with molecular weights (M_r) 45, 66 and >66 kDa and monomeric kafirins and zeins. Protein-body-enriched samples of sorghum had more 45–50 kDa oligomers than those of maize. In cooked sorghum, some of these were resistant to reduction. Pepsin-indigestible residues from protein-body-enriched samples consisted mainly of α-zein (uncooked and cooked maize) or α-kafirin (uncooked sorghum), whilst cooked sorghum had in addition, β- and γ-kafirin and reduction-resistant 45–50 kDa oligomers. Cooking appears to lead to formation of disulphide-bonded oligomeric proteins that occurs to a greater extent in sorghum than in maize. This may explain the poorer protein digestibility of cooked sorghum.     

Effect of natural fermentation on protein fractions and in vitro protein digestibility of rice

Seaweeds are rich sources of dietary fiber which possess diverse physiological functions in the colon. In the present study, the modulating effect of feeding seatangle (Laminaria japonica), a fiber-rich seaweed, on initiation and postinitiation of rat colon carcinogenesis was investigated. Four groups of animals were exposed to two weekly injections of a chemical carcinogen azoxymethane (AOM). Animals were fed a fiber-free semisynthetic diet or a diet containing 15% seatangle (4.7 g dietary fiber/100 g diet) during initiation, postinitiation or initiation postinitiation phase of carcinogenesis. Study results showed that animals fed the seatangle-containing diet had a significantly decreased number of both aberrant crypts and aberrant crypt foci in the colon. Also, labeling indices and proliferation zones were signi- ficantly reduced in the colon of the rats fed a seatangle diet. All of the seatangle feeding regimens used in this study were effective in reducing aberrant crypt formation indicating anticarcinogenic effects are mediated through both the blocking of initiation and the suppression of cell proliferation in initiated cells. These results suggest that a diet containing seatangle may decrease the risk of developing colon cancer although the precise cellular mechanisms involved in anticarcinogenic effects of seatangle should be further examined.