Comparison of 1-(2-naphthyloxymethylcarbonyl) pyrrolidine,PP-20/DPJ,newly synthesized compound with the nootropic drug piracetam in normal and aluminum-induced neurotoxic state

Nootropic drugs like piracetam, oxiracetam, and nifiracetam are used as memory enhancers. They are thought to directly influence the energetic processes in the brain and produce elevated acetylcholine levels, but they lack protecting therapeutic potentials. Thus, there is a continuing effort directed towards developing a new cognition-enhancing agent, which would be more effective than the currently available drugs, and 2-Naphthyloxy derivatives (PP-20/DPJ) were consequently developed. This in vivo study was designed to compare the memory enhancing potential of PP-20/DPJ with the known nootropic agent, piracetam, in aluminum (Al)-induced neurotoxic model. Results indicated that PP-20/DPJ improved the short-term memory and cognitive behaviors similar to piracetam. Further, both the compounds were equally effective in elevating the acetylcholinesterase and Mg⁺-ATPase enzyme activity in both the brain regions after Al treatment. Thus the current study suggests, that PP-20/DPJ acts as both a cognition-enhancing agent and as a metabolic enhancer.     

不同pH条件下Cr6+对3种藻的毒性效应(The Toxicological Effects of Cr6+ on Chlorella Vulgaris, Scenedesmus Obliquus and Microcystis Aeruginosa at Different pH Values)

目前我国水质量生态基准的研究较为零星、分散.研究了不同pH条件下Cr6+对3种藻的毒性效应,以期为我国水生态基准的科学制定以及基准的相关研究工作提供参考.选取小球藻、斜生栅藻和铜绿微囊藻3种典型的藻种,在pH为7.0,8.0和9.0三个条件下,依据OECD-201藻类生长抑制实验指南,以72h藻生物量为测试终点,计算3种藻的比生长率,以及Cr6+对3种藻产生毒性效应的NOEC、LOEC、EC10和EC20值.结果表明,在本实验条件下,在不同pH条件下藻种生长不同,小球藻的最适pH值为7.0,斜生栅藻和铜绿微囊藻的最适pH值为9.0;在不同pH条件下,Cr6+对小球藻、斜生栅藻和铜绿微囊藻的毒性作用不同,Cr6+对小球藻在pH=7.0时毒性最小,对斜生栅藻和铜绿微囊藻在pH=9.0时的毒性最小.在藻最适生长的pH条件下,Cr6+的毒性可以达到最小程度;铜绿微囊藻对Cr6+比斜生栅藻和小球藻更加敏感.     

A chromosome 21-specific cosmid cocktail for the detection of chromosome 21 aberrations in interphase nuclei

Fluorescent in situ hybridization (FISH) with a 21q11-specific probe (CB21c1) consisting of three non-overlapping cosmids has been applied to interphase amniocytes of pregnancies at increased risk for fetal aneuploidy (N = 78) and to interphase lymphocytes, cultured and uncultured, of patients referred for Down syndrome (N = 19 and 28, respectively). In the uncultured amniocytes, six chromosome aberrations were detected: three cases of trisomy 21, a triploidy, a de novo 46,XX,t(21q21q), and a mosaic 46,XY/47,XY,+dic(21)(q11)/48,XY,+dic(21)(q11), +del(21)(q11). In 15 cultured and 20 uncultured blood samples, FISH correctly diagnosed trisomy 21 (full or mosaic) at the interphase level, which was confirmed in all cases by subsequent karyotyping. Because of specific and strong signals in interphase nuclei, CB21c1 appears to be a useful tool for the rapid detection of chromosome 21 abnormalities.     

46,XY,dup(10q) in direct CVS preparation and mosaic 48,XXXY,dup(10q) in CVS long-term culture and fetal tissue

Chorionic villus sampling (CVS) was performed on a 40-year-old woman at 9 1/2 menstrual weeks because of advanced maternal age. The direct preparation showed 46,XY,dup(10)(q11.2q23.2). CVS long-term culture and fetal tissue revealed a rare additional abnormality: 48,XXXY,dup(10)(q11.2q23.2). This abnormality represented the major cell line (>85 per cent in 691 cells) in an (XY)/XXY/XXXY/(XXXXY) mosaic (all cell lines presumably bearing the dup(10q); the presence of XY and XXXXY cell lines is uncertain). To our knowledge, this is the first report of trisomy 10q11-q23 and of prenatally detected 48,XXXY in chorionic villi. The mosaic could have resulted from early post-zygotic non-disjunctions in a 46,XY,dup(10q) or 47,XXY,dup(10q) zygote. The results from DNA studies of four polymorphisms, mapped to Xp and Xq, support this theory. The literature on prenatally detected cases with sex chromosome tetrasomy and pentasomy and those with additional autosomal abnormalities is reviewed. The reported case underlines the problem of false-negative findings when only direct CVS preparations are karyotyped.     

一株溶铜绿微囊藻真菌的分离与鉴定

从土壤中分离得到一株具有溶藻能力的真菌,命名为J20。经形态学和18srDNA序列对比分析鉴定,J20菌株属于青霉属(Peniciliium)。研究了J20菌株对铜绿微囊藻DS的溶藻效果,初步探讨了其溶藻方式及溶藻物质。结果表明:该菌株对铜绿微囊藻DS有一定的去除效果,实验第3天时,试验组比对照组的叶绿素a减少达82%;该菌株培养物的最低有效抑藻效应浓度为1∶100(即向100mL藻液中加入1mL菌液);该菌株通过分泌胞外产物的方式溶解铜绿微囊藻且溶藻物质主要为具有热稳定性的非蛋白类物质。     

1st international round robin test on safety characteristics of hybrid mixtures

There is no applicable existing standard for the determination of safety characteristics for hybrid mixtures. While developing a new standard in a joint research project in Germany first results from parameter studies led to a standard procedure that can be adopted by laboratories that are already testing dusts in the so called 20L-sphere with as little additional effort as necessary. In fact, one of the main objectives of this research project was to keep modifications and adjustments from the generally accepted dust testing procedures as easy and minimal as possible so as to limit potential deviations from one laboratory to another.In this first round robin test on hybrid mixtures ever, with methane as gas component and a specific corn starch as dust sample, the practicality of the whole procedure, the scattering of the results and the deviation between the testing apparatuses is investigated. This paper summarizes the experimental procedure adopted and objectives of the first round-robin phase involving three of the four original German companies, plus volunteering laboratories from Australia, Belgium, Czech Republic, France, Poland and P.R. China. The results will have an impact on the new standard and may lead to robust data for later simulation purposes.