Inhibitory effects of quinidine and quinine on liver microsome oxidation enzymes in man and rat

AIM: To compare the inhibitory effects of quinidine and quinine on liver microsome bufuralol 1'-hydroxylase (BH), aryl hydrocarbon hydroxylase (AHH), and 7-ethoxycoumarin O-deethylase (ED) activities in man and rat. METHODS: A normal phase HPLC and the fluorescence spectrometry were used to assay the enzyme activities. RESULTS: Both quinidine and quinine produced a concentration-dependent inhibition to liver microsome BH, AHH, and ED in man and rat. Their median inhibitory concentrations (IC50) on liver microsome BH, AHH, and ED low and high affinity phases were 0.2, 378, 2952, and > 5000 mumol.L-1 for quinine in man, 290, 613, 1465, 1595, mumol.L-1 for quinidine in rat; 29, 207, 808, and > 5000 mumol.L-1 for quinine in man, and 31, 54, 597, and 2508 mumol.L-1 for quinine in rat, respectively. CONCLUSION: Quinidine is a species- and stereo-selective potent inhibitor to human liver microsome BH.     

The heat-shock gene hsp83 of Drosophila auraria: genomic organization, nucleotide sequence, and long antiparallel coupled ORFs (LAC ORFs)

The genomic organization of the hsp83 gene of Drosophila auraria, a far-eastern endemic species belonging to the montium subgroup of the melanogaster species group, is presented here. Based on in situ hybridization on polytene chromosomes, cDNA and genomic clone mapping, nucleotide sequencing, and genomic Southern analysis, hsp83 is shown to be present as a single-copy gene at locus 64B on the 3L chromosome arm in D. auraria. This gene is organized into two exons separated by a 929-bp intron. The first exon represents the mRNA leader sequence and is not translated, while the coding region, having a length of 2,151 bp, is solely included in the second exon. Nucleotide sequence comparisons of D. auraria hsp83 with homologous sequences from other organisms show high conservation of the coding region (88-92% identity) in the genus Drosophila, in addition to the conserved genomic organization of two-exons-one-intron, of comparable size and arrangement. A phylogenetic tree based on the protein sequences of homologous genes from representative organisms is in accord with the accredited phylogenetic position of D. auraria. In the hsp83 gene region, a second case of long antiparallel coupled open reading frames (LAC ORFs) for this species was found. The antiparallel to the hsp83 gene ORF is 1,554 bases long, while the two ORFs overlap has a size of 1,548 bp. The anti-hsp83 ORF does not show significant homology to any known gene sequences. In addition, no similar LAC ORF structures were found in homologous gene regions of other organisms.     

Clonal analysis of the in vivo differentiation potential of keratinocytes

PURPOSE: This study investigated the in vivo differentiation of conjunctival keratinocytes. METHODS: Keratinocytes from the fornical region of the conjunctival epithelium were isolated and plated at low density (5 x 102 per 100-mm dish) in Dulbecco's minimum essential medium containing 20% fetal bovine serum in the presence of mitomycin C-treated 3T3 feeder cells. At this density, only single, isolated cells were attached after overnight culture. Eight days later, small, well-isolated colonies separated from one another by the feeder cells were detached as a sheet from the dish and were injected subcutaneously into the flanks of BALB/c athymic mice through an 18-gauge needle. Within a day, a small firm nodule appeared at the site of injection. At different time points, the animals were killed, and the nodules were excised for morphologic, histogeometric, and cell kinetic analyses. RESULTS: Each implanted colony derived from a single cell gave rise to a single epithelial cyst lined with a reconstituted stratified epithelium. Goblet-like cells loaded with periodic acid-Schiff-positive cytoplasmic granules began to appear singularly in some of the cysts by day 8 postimplantation and were observed in approximately 85% of the cysts by day 14. CONCLUSIONS: Because the cysts formed were derived from clonal populations of epithelial cells and the majority of cysts had a mixed keratinocyte-goblet cell phenotype, these results suggest strongly the existence of a bipotent precursor cell in conjunctival epithelium that can give rise to both goblet and nongoblet cells. This system can be used to study factors that can influence the commitment of pluripotent epithelial stem cells to divergent pathways of differentiation.     

低频无线Mesh系统解决方案投入市场

由美国Strix系统有限公司研发的低频无线网络网格（Mesh）通信产品——UItraMANET自组网无线设备正式投入行业市场。     

“太阳神2A”升空

2004年12月18日，一枚欧洲“阿丽亚娜-5”型运载火箭将法国一颗“太阳神2A”军事侦察卫星送入了太空轨道，“太阳神2A”军事侦察卫星进入距地面435英里的同步轨道。箭上另外六颗小型科学卫星也已经顺利进入预定轨道。这是11年来“阿丽亚娜”系列火箭首次进行“一箭七星”的发射任务。     

Diffusion, perfusion, and T2 magnetic resonance imaging of anti-intercellular adhesion molecule 1 antibody treatment of transient middle cerebral artery occlusion in rat

The effect of anti-intercellular adhesion molecule-1 (anti-ICAM-1) antibody treatment of transient (2 h) middle cerebral artery (MCA) occlusion in the rat was measured using diffusion (DWI)-, T2 (T2I)- and perfusion (PWI)-weighted magnetic resonance imaging. Rats were treated upon reperfusion with an anti-ICAM-1 monoclonal antibody (n=11) or a control antibody (n=7). DWI, T2I and PWI were performed before, during, and after induction of focal cerebral ischemia from 1 h to 7 days. In both groups, the apparent diffusion coefficient of water (ADCw) and cerebral blood flow (CBF) values in the ischemic region significantly declined from the preischemic ADCw values (p<0. 05). The post ischemic increase in T2 of the control group was significantly higher at 48 h than in the anti-ICAM-1 treated group (p<0.05). CBF was not significantly different between the two groups. The temporal profiles of MRI cluster analysis, which combines ADCw and T2 maps into a single image, was significantly different between groups. These data suggest that the neuroprotective effect of anti-ICAM-1 antibody treatment is reflected in reductions of T2 and lesion growth during reperfusion and may not be associated with increased cerebral perfusion.