Nitric oxide modulates the expression of endothelial cell adhesion molecules involved in angiogenesis and leukocyte recruitment

Tumor angiogenesis and immune response have in common to be cell recognition mechanisms, which are based on specific adhesion molecules and dependent on nitric oxide (NO^•). The aim of the present study is to deepen the mechanisms of angiogenesis and inflammation regulation by NO^• to find out the molecular regulation processes that govern endothelial cell permeability and leukocyte transmigration.Effects of NO^•, either exogenous or produced in hypoxic conditions, were studied on microvascular endothelial cells from skin and lymph node because of their strong involvement in melanoma progression. We found that NO^• down-regulation of pseudo-vessel formation was linked to a decrease in endothelial cell ability to adhere to each other which can be explain, in part, by the inhibition of PECAM-1/CD31 expression. On the other hand, NO^• was shown to be able to decrease leukocyte adhesion on an endothelial monolayer, performed either in static or in rolling conditions, and to modulate differentially CD34, ICAM-1/CD54, ICAM-2/CD102 and VCAM-1/CD106 expression.In conclusion, during angiogenesis and leukocyte recruitment, NO^• regulates cell interactions by controlling adhesion molecule expression and subsequently cell adhesion. Moreover, each endothelial cell type presents its own organospecific response to NO^•, reflecting the functions of the tissue they originate from.     

Ectopic over-expression of peroxisomal ascorbate peroxidase (SbpAPX) gene confers salt stress tolerance in transgenic peanut (Arachis hypogaea)

Peroxisomal ascorbate peroxidase gene (SbpAPX) of an extreme halophyte Salicornia brachiata imparts abiotic stress endurance and plays a key role in the protection against oxidative stress. The cloned SbpAPX gene was transformed to local variety of peanut and about 100 transgenic plants were developed using optimized in vitro regeneration and Agrobacterium mediated genetic transformation method. The T₀ transgenic plants were confirmed for the gene integration; grown under controlled condition in containment green house facility; seeds were harvested and T₁ plants were raised. Transgenic plants (T₁) were further confirmed by PCR using gene specific primers and histochemical GUS assay. About 40 transgenic plants (T₁) were selected randomly and subjected for salt stress tolerance study. Transgenic plants remained green however non-transgenic plants showed bleaching and yellowish leaves under salt stress conditions. Under stress condition, transgenic plants continued normal growth and completed their life cycle. Transgenic peanut plants exhibited adequate tolerance under salt stress condition and thus could be explored for the cultivation in salt affected areas for the sustainable agriculture.     

6-苄基腺嘌呤对平菇和香菇菌丝体4种胞外酶活性的影响

在马铃薯液体培养基中,通过活加不同剂量的6－苄基腺嘌呤（6－BA）,测定了平菇和香菇菌丝体4种胞外酶活性的变化。结果表明,低浓度的外源6－BA对平菇、香菇菌丝体4种胞外酶活性都有促进作用,高浓度时则逐渐抑制酶活性。其中,培养液浓度为1．5mg/100mL时,它们扔包外粉酶（Amy）、羧甲基纤维素酶（CMC）、过氧化氢酶（CAT）的活性最高;而它们的胞外蛋白酶的最适浓度为0．5mg/100mL。     

Induction of synchronous secondary somatic embryogenesis in Camellia sinensis (L.) O. Kuntze

Nutritional effect of nitrate salts of potassium and ammonium, together with different concentrations of sulphate salts of aluminium, potassium, magnesium, and ammonium on secondary somatic embryogenesis, wereinvestigated. Nitrate salts of potassium (9.39 mmol/L) and ammonium (10.31 mmol/L) with only 1.5 mmol/L potassium sulphate produced maximum number of synchronous secondary embryos (i.e. 20-25 secondary embryos per primary embryo in 91.6 percnt; responsive explants).Of the different factorial combinations of glutamine, BAP, and IBA tested, maximum number of synchronous secondary embryos developed on a medium supplemented with 8.88 μmol/L BAP, 0.98 μmol/L IBA and 10 mmol/L glutamine.Synchronous and normal development of secondary embryos could thus be obtained when optimal concentrations of PGRs, glutamine, nitrates, and salts of potassium sulphate were combined together.Germination of the embryos (up to 52 percnt;) was acheived only when sulphate salts of potassium were removed from the medium.     

氧化石墨烯/十二烷基二甲基苄基氯化铵复合物的制备和抗菌性能研究

本文研究了氧化石墨烯/十二烷基二甲基苄基氯化铵( GO-1227)复合抗菌材料的制备及其抗菌性能。通过傅立叶红外光谱的检测,确定GO-1227复合物已经成功合成。为了研究复合物的抗菌活性,以大肠杆菌为代表,通过观察大肠杆菌的表面形貌变化和细菌体外离子浓度变化,证明GO-1227复合物具有相对于原材料更好的抗菌性能。     

提高丙酮丁醇梭菌产溶剂稳定性及防止退化的研究

在丙酮丁醇梭菌连续传代过程中,添加乙酸钠可增强其稳定性,同时在未添加乙酸钠的发酵液中分离获得溶剂产量明显降低的退化菌株DNU83,其丁醇产量为2.33 g·L-1,仅为初始菌株的1/6.培养基中添加乙酸钠、丁酸钠或K2 HPO4等弱酸盐均可恢复退化菌株的产溶剂能力,如同时添加苄基紫精,可显著促进丁醇合成.7％玉米培养基中添加4 g·L -1 K2 HPO4和30 mg·L-1苄基紫精,丁醇产量可达18.01 g·L-1,总溶剂21.59 g·L-1,丁醇比为83.43％,丁醇产量较未退化菌株NU22提高24.09％.     

L-酪氨酸苄酯的合成及其影响因素研究

以L-酪氨酸和苯甲醇为原料合成一种新型的L-酪氨酸衍生物——L-酪氨酸苄酯。首先用苯甲醇与氯化亚砜反应生成氯化亚硫酸酯,合成物再与L-酪氨酸发生酯化反应得到L-酪氨酸苄酯,其结构经质谱(MS)分析法确证。在此基础上研究了影响该合成工艺的主要因素,即原料配比、反应温度、反应时间、pH值。结果显示合成L-酪氨酸苄酯的较佳工艺条件为:物料摩尔比mol(SOCl2)∶mol(L-酪氨酸)=1.3∶1.0,室温下反应3h,120℃下反应2h,后处理溶液pH为7.5。本工艺适宜于工业化大规模生产。     

New CycloAMB-Nucleoside Phosphonate Prodrugs

cycloSal- and cycloAmb-nucleoside phosphonate prodrugs of PMEA were synthesized and characterized. Each of these compounds showed different disadvantages in hydrolysis. Thus, a new series of cycloAminobenzyl(cycloAmb)-PMEA prodrugs was synthezised and studied with regard to their hydrolysis properties and biological activity.     

Male specific natural products in the bug, Leptoglossus phyllopus: Chemistry and possible function

In the Coreoidea and some allied groups, male adults possess an abdominal gland opening through a midventral ostiole in the 7–8th abdominal intersegmental membrane. Using a GC-MS system, the following aromatic volatiles were identified in the abdominal gland secretion from males of the leaf footed bug, Leptoglossus phyllopus: guaiacol, benzyl alcohol, syringaldehyde, methyl p-hydroxybenzoate, acetosyringone, and vanillin. Males from which the glands were removed still mated and were competitive with control males for a limited number of females. The ventral abdominal gland secretion may act as a long-range attractant of females. The possibility that attraction of females by males in Heteroptera is an adaptation facilitating colonization of successional habitats is discussed.