Microwave enhanced solid support synthesis of fluorine containing benzopyrano-triazolo-thiadiazepines as potent anti-fungal agents

A facile, dry media procedure has been developed for the synthesis of a series of a new class of fluorine containing 3-alkyl-7-chloro-11a,12-dihydro-11-phenyl-12-(substituted aryl)-11H-benzopyrano[4,3-e][1,2,4]-triazolo[3,4-b][1,3,4]-thiadiazepines (4a-k) under microwaves using basic alumina as solid support. The reaction time has been brought down from hours (60-65 h) to minutes (3-5 min) with improved yield as compared to conventional method, demonstrating the versatility of the process. The method reported herein is devoid of the hazards of solution-phase reactions. The synthesized compounds have been screened 'in vitro' for anti-fungal activity against Rhizoctonia solani, Fusarium oxysporum and Collectotrichum capsici. Most of the compounds have shown good activity against these pathogens.     

Synapsin I is a major endogenous substrate for protein L-isoaspartyl methyltransferase in mammalian brain

The accumulation of potentially deleterious L-isoaspartyl linkages in proteins is prevented by the action of protein L-isoaspartyl O-methyltransferase, a widely distributed enzyme that is particularly active in mammalian brain. Methyltransferase-deficient (knock-out) mice exhibit greatly increased levels of isoaspartate and typically succumb to fatal epileptic seizures at 4-10 weeks of age. The link between isoaspartate accumulation and the neurological abnormalities of these mice is poorly understood. Here, we demonstrate that synapsin I from knock-out mice contains 0.9 +/- 0.3 mol of isoaspartate/mol of synapsin, whereas the levels in wild-type and heterozygous mice are undetectable. Transgenic mice that selectively express methyltransferase only in neurons show reduced levels of synapsin damage, and the degree of reduction correlates with the phenotype of these mice. Isoaspartate levels in synapsin from the knock-out mice are five to seven times greater than those in the average protein from brain cytosol or from a synaptic vesicle-enriched fraction. The isoaspartyl sites in synapsin from knock-out mice are efficiently repaired in vitro by incubation with purified methyltransferase and S-adenosyl-L-methionine. These findings demonstrate that synapsin I is a major substrate for the isoaspartyl methyltransferase in neurons and suggest that isoaspartate-related alterations in the function of presynaptic proteins may contribute to the neurological abnormalities of mice deficient in this enzyme.     

Growth and nutrient removal of three macrophytes in response to concentrations and ratios of N and P

Wastewater from different sources shows great differences in concentrations and ratios of N and P. In order to choose suitable plant species to remove excess N and/or P from polluted waters, it is important to know the performances of these plants under different N and P concentrations. In this study, we investigated the growth and N and P removal rate of three macrophytes, Coix lacryma-jobi, Iris wilsonii, and Arundo donax under six N and P combination treatments. C. lacryma-jobi preferred higher N and P concentrations (16 mg N L^?1 and 3.2 mg P L^?1), and increasing N supply could increase its P removal rate. I. wilsonii exhibited a growth preference at a combination of moderate N and P concentrations (8 mg N L^?1 and 0.8 mg P L^?1). A. donax could grow well at all combinations of N and P and had significantly higher relative growth rate and N and P removal rates than the other two species. These results showed A. donax is a promising species to treat various polluted waters and the other two species can be used specifically to treat certain types of wastewater.     

市售长叶松油和锡兰肉桂油对登革热媒蚊埃及伊蚊的灭幼效果(英文)

松油和桂皮油由于具有芳香性气味, 因而成为良好的成虫驱避剂, 但是关于它们对蚊虫的杀幼虫作用研究不多。为揭示市售的长叶松Pinus longifolia油和锡兰肉桂Cinnamomum zeylanicum油对来源于印度德里的埃及伊蚊Aedes aegypti 4龄幼虫的毒杀潜力, 我们进行了室内研究, 以幼虫死亡率及行为改变和形态改变等指标评估其杀幼虫潜力。结果表明： 两种油对埃及伊蚊4龄幼虫均具有毒杀作用, 且松油的灭幼效果优于桂皮油。松油的LC₅₀和LC₇₀ 值分别为0.33093 mg/L 和0.54476 mg/L, 而桂皮油的LC₅₀和LC₇₀ 值分别为0.63159 mg/L和0.77736。进一步观察发现, LC₉₀剂量下桂皮油的杀幼虫潜力强于松油, 其LC₉₀为1.11879 mg/L, 而松油的LC₉₀为 1.04915 mg/L。在处理的幼虫中观察到行为改变, 如兴奋、 坐立不安、 颤抖、 痉挛然后瘫痪, 说明这两种油可能对其神经肌肉系统产生了影响。显微观察处理幼虫的形态改变发现, 与对照相比, 大多数器官的外观正常, 只是肛鳃略为内收缩而引起结构畸形, 提示肛腮可能是这两种油的作用位点, 腮的功能异常引起了幼虫死亡。这两种油品可开发用作防治蚊虫的新型杀幼虫药剂。     

ARFGAP1 Is Dynamically Associated with Lipid Droplets in Hepatocytes

The ARF GTPase Activating Protein 1 (ARFGAP1) associates mainly with the cytosolic side of Golgi cisternal membranes where it participates in the formation of both COPI and clathrin-coated vesicles. In this study, we show that ARFGAP1 associates transiently with lipid droplets upon addition of oleate in cultured cells. Also, that addition of cyclic AMP shifts ARFGAP1 from lipid droplets to the Golgi apparatus and that overexpression and knockdown of ARFGAP1 affect lipid droplet formation. Examination of human liver tissue reveals that ARFGAP1 is found associated with lipid droplets at steady state in some but not all hepatocytes.     

Mechanochemical regulation of oscillatory follicle cell dynamics in the developing Drosophila egg chamber

During tissue elongation from stage 9 to stage 10 in Drosophila oogenesis, the egg chamber increases in length by ∼1.7-fold while increasing in volume by eightfold. During these stages, spontaneous oscillations in the contraction of cell basal surfaces develop in a subset of follicle cells. This patterned activity is required for elongation of the egg chamber; however, the mechanisms generating the spatiotemporal pattern have been unclear. Here we use a combination of quantitative modeling and experimental perturbation to show that mechanochemical interactions are sufficient to generate oscillations of myosin contractile activity in the observed spatiotemporal pattern. We propose that follicle cells in the epithelial layer contract against pressure in the expanding egg chamber. As tension in the epithelial layer increases, Rho kinase signaling activates myosin assembly and contraction. The activation process is cooperative, leading to a limit cycle in the myosin dynamics. Our model produces asynchronous oscillations in follicle cell area and myosin content, consistent with experimental observations. In addition, we test the prediction that removal of the basal lamina will increase the average oscillation period. The model demonstrates that in principle, mechanochemical interactions are sufficient to drive patterning and morphogenesis, independent of patterned gene expression.