Inversion in the H-2 complex of t-haplotypes in mice

Mouse t-haplotypes demonstrate strong linkage disequilibrium between t-lethal genes and specific H-2 types, presumably a result of recombination suppression between t and normal chromosomes. The observation of free recombination occurring between two complementary t-haplotypes suggested a chromosomal mismatch between t and normal chromosomes. Recent data showing the H-2 complex to be misplaced relative to two other markers, T and tf, in t-haplotypes suggested that chromosomal rearrangement in t-haplotypes might be the basis for their 'mismatch' with the normal chromosome. Here, to analyse the molecular nature of the rearrangement, we have cloned a polymorphic H-2 class I restriction fragment, which had previously been shown to map centromeric to the serologically defined H-2 complex in t-haplotypes. Genetic mapping studies show that this cloned t-DNA is homologous to the H-2 D region of wild-type chromosomes, and that the E alpha Ia gene maps telomeric to this DNA fragment in t-haplotypes, in contrast to its orientation in wild-type chromosomes. These results give molecular evidence for an inversion of H-2 in t-haplotypes, which may be at least partially responsible for recombination suppression and thus for linkage disequilibrium.     

Expression and self-assembly of Heterocapsa circularisquama RNA virus-like particles synthesized in Pichia pastoris

Heterocapsa circularisquama RNA virus(HcRNAV) is the first single-stranded RNA virus to be characterized that infects dinoflagellates.The ability of HcRNAV coat protein(HcRNAV CP) to self-assemble into virus-like particles(VLPs) in vitro suggested that heterologous expression was possible,and that the VLPs might be ideal nanocontainers for the targeted delivery of genes and chemicals.In this paper,we report the expression of a codon-optimized HcRNAV 109 CP gene in Pichia pastoris and the production of self-assembled HcRNAV VLPs using large-scale fermentation.The HcRNAV 109 CP gene was synthesized according to the codon preference of P.pastoris and cloned into a pPICZA vector.The recombinant plasmid pPICZA-CPsyns was transformed into P.pastoris by electroporation.The resulting yeast colonies were screened by PCR and analyzed for protein expression by SDS polyacrylamide gel electrophoresis.After large-scale fermentation,the yield of HcRNAV CPsyns reached approximately 2.5 g L 1 within 4 d.The HcRNAV VLPs were purified using PEG precipitation followed by cesium chloride density gradient ultracentrifugation,and were subsequently analyzed using UV spectrophotometry and transmission electron microscopy.Fluorescence dye-labeled myoglobin was loaded into the cages of the HcRNAV VLPs and the encapsulation was confirmed by fluorescence spectroscopy.The results point to the possible utilization in pharmacology or nanotechnology of HcRNAV VLPs produced by P.pastoris fermentation.     

Salt effects on formation of microcrystallites in poly(vinyl alcohol) gels prepared by cast-drying method

The preparation method of poly(vinyl alcohol)(PVA) gels by a simple cast-drying technique using salt solutions was reported in the present investigation.The effects of the salt concentration on the macro- and microscopic properties were examined in detail,and the relationships between macroscopic properties,such as swelling ratio,mechanical strength,and the network microstaicture were presented.It was found that the swelling ratio of PVA cast gel increased largely by adding a small amount of salt, and de...     

Forecasting economic indicators using a consumer sentiment index: Survey‐based versus text‐based data

Given the confirmed effectiveness of the survey‐based consumer sentiment index (CSI) as a leading indicator of real economic conditions, the CSI is actively used in making policy judgments and decisions in many countries. However, although the CSI offers qualitative information for presenting current conditions and predicting a household's future economic activity, the survey‐based method has several limitations. In this context, we extracted sentiment information from online economic news articles and demonstrated that the Korean cases are a good illustration of applying a text mining technique when generating a CSI using sentiment analysis. By applying a simple sentiment analysis based on the lexicon approach, this paper confirmed that news articles can be an effective source for generating an economic indicator in Korea. Even though cross‐national comparative research results are suited better than national‐level data to generalize and verify the method used in this study, international comparisons are quite challenging to draw due to the necessary linguistic preprocessing. We hope to encourage further cross‐national comparative research to apply the approach proposed in this study.     

The phosphoinositide PI(3,5)P2 mediates activation of mammalian but not plant TPC proteins: functional expression of endolysosomal channels in yeast and plant cells

Two-pore channel proteins (TPC) encode intracellular ion channels in both animals and plants. In mammalian cells, the two isoforms (TPC1 and TPC2) localize to the endo-lysosomal compartment, whereas the plant TPC1 protein is targeted to the membrane surrounding the large lytic vacuole. Although it is well established that plant TPC1 channels activate in a voltage- and calcium-dependent manner in vitro, there is still debate on their activation under physiological conditions. Likewise, the mode of animal TPC activation is heavily disputed between two camps favoring as activator either nicotinic acid adenine dinucleotide phosphate (NAADP) or the phosphoinositide PI(3,5)P₂. Here, we investigated TPC current responses to either of these second messengers by whole-vacuole patch-clamp experiments on isolated vacuoles of Arabidopsis thaliana. After expression in mesophyll protoplasts from Arabidopsis tpc1 knock-out plants, we detected the Arabidopsis TPC1-EGFP and human TPC2-EGFP fusion proteins at the membrane of the large central vacuole. Bath (cytosolic) application of either NAADP or PI(3,5)P₂ did not affect the voltage- and calcium-dependent characteristics of AtTPC1-EGFP. By contrast, PI(3,5)P₂ elicited large sodium currents in hTPC2-EGFP-containing vacuoles, while NAADP had no such effect. Analogous results were obtained when PI(3,5)P₂ was applied to hTPC2 expressed in baker’s yeast giant vacuoles. Our results underscore the fundamental differences in the mode of current activation and ion selectivity between animal and plant TPC proteins and corroborate the PI(3,5)P₂-mediated activation and Na⁺ selectivity of mammalian TPC2.     

Molecular mechanisms in therapy of acid-related diseases

Inhibition of gastric acid secretion is the mainstay of the treatment of gastroesophageal reflux disease and peptic ulceration; therapies to inhibit acid are among the best-selling drugs worldwide. Highly effective agents targeting the histamine H2 receptor were first identified in the 1970s. These were followed by the development of irreversible inhibitors of the parietal cell hydrogen-potassium ATPase (the proton pump inhibitors) that inhibit acid secretion much more effectively. Reviewed here are the chemistry, biological targets and pharmacology of these drugs, with reference to their current and evolving clinical utilities. Future directions in the development of acid inhibitory drugs include modifications of current agents and the emergence of a novel class of agents, the acid pump antagonists. Received 30 May 2007; received after revision 15 August 2007; accepted 13 September 2007     

Galectin-3 stabilizes heterogeneous nuclear ribonucleoprotein Q to maintain proliferation of human colon cancer cells

Comparative analysis of proteomes using 5-fluorouracil (5-FU)-resistant human colon cancer cell line revealed that decreased galectin-3 expression was significantly associated with retarded proliferation. However, in the presence of 5-FU proliferation rate of cells with suppressed galectin-3 expression did not differ from that of cells with normal galectin-3 expression, even galectin-3 suppression augmented apoptosis. Mechanism by which galectin-3 regulates cancer cell proliferation has been identified in immunoprecipitates of the anti-galectin-3 antibody. Heterogeneous nuclear ribonucleoprotein Q (hnRNP Q) was identified as a protein interacting with galectin-3. Interestingly, while galectin-3 protein was not affected by the hnRNP Q level, its suppression was accompanied by a decrease in hnRNP Q expression. The present study demonstrates that galectin-3 stabilizes hnRNP Q via complex formation, and reduction in the hnRNP Q level leads to slow proliferation and less susceptibility to 5-FU. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. B.C.Yoo; S-H.Hong; These two authors contributed equally to this work. Received 10 September 2008; received after revision 19 October 2008; accepted 07 November 2008     

Forecasting for the LCD monitor market

The TFT‐LCD (thin‐film transistor–liquid crystal display) industry is one of the key global industries with products that have high clock speed. In this research, the LCD monitor market is considered for an empirical study on hierarchical forecasting (HF). The proposed HF methodology consists of five steps. First, the three hierarchical levels of the LCD monitor market are identified. Second, several exogenously driven factors that significantly affect the demand for LCD monitors are identified at each level of product hierarchy. Third, the three forecasting techniques—regression analysis, transfer function, and simultaneous equations model—are combined to forecast future demand at each hierarchical level. Fourth, various forecasting approaches and disaggregating proportion methods are adopted to obtain consistent demand forecasts at each hierarchical level. Finally, the forecast errors with different forecasting approaches are assessed in order to determine the best forecasting level and the best forecasting approach. The findings show that the best forecast results can be obtained by using the middle‐out forecasting approach. These results could guide LCD manufacturers and brand owners on ways to forecast future market demands. Copyright 2008 John Wiley & Sons, Ltd.