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Helicobacter pylori neutrophil-activating protein (HP-NAP)-induced production of reactive oxygen species (ROS) by neutrophils and monocytes is regulated by pertussis toxin (PTX)-sensitive G proteins, whereas HP-NAP-induced cytokine secretion by monocytes is mediated by Toll-like receptor 2 (TLR2). However, it is unclear whether TLR2 participates in HP-NAP-induced cytokine secretion by neutrophils. Here, all-trans retinoic acid (ATRA)-induced differentiated HL-60 cells were first employed as a neutrophil model to investigate the molecular mechanisms underlying neutrophil responses to HP-NAP. HP-NAP-induced ROS production in ATRA-induced differentiated HL-60 cells is mediated by the PTX-sensitive heterotrimeric G protein-dependent activation of extracellular signal-regulated kinase 1/2 and p38-mitogen-activated protein kinase, which is consistent with the findings reported for human neutrophils. Next, whether TLR2 participated in HP-NAP-induced secretion of interleukin-8 (IL-8) was investigated in neutrophils and ATRA-induced differentiated HL-60 cells. In both cells, TLR2 participated in HP-NAP-induced IL-8 secretion but not HP-NAP-induced ROS production. Interestingly, PTX-sensitive G proteins also contributed to the HP-NAP-induced secretion of IL-8 from neutrophils and the differentiated HL-60 cells. Our ELISA-based binding assay further revealed the competitive binding of Pam3CSK4, a TLR2 agonist, and HP-NAP to TLR2, which suggests the presence of specific and direct interactions between HP-NAP and TLR2. Thus, HP-NAP directly interacts with and activates TLR2 to induce IL-8 secretion in neutrophils and ATRA-induced differentiated HL-60 cells.

Human poly(ADP)-ribose polymerase-1 (PARP1) is a global regulator of various cellular processes, from DNA repair to gene expression. The underlying mechanism of PARP1 action during transcription remains unclear. Herein, we have studied the role of human PARP1 during transcription through nucleosomes by RNA polymerase II (Pol II) in vitro. PARP1 strongly facilitates transcription through mononucleosomes by Pol II and displacement of core histones in the presence of NAD+ during transcription, and its NAD+-dependent catalytic activity is essential for this process. Kinetic analysis suggests that PARP1 facilitates formation of “open” complexes containing nucleosomal DNA partially uncoiled from the octamer and allowing Pol II progression along nucleosomal DNA. Anti-cancer drug and PARP1 catalytic inhibitor olaparib strongly represses PARP1-dependent transcription. The data suggest that the negative charge on protein(s) poly(ADP)-ribosylated by PARP1 interact with positively charged DNA-binding surfaces of histones transiently exposed during transcription, facilitating transcription through chromatin and transcription-dependent histone displacement/exchange.

This study employs social network analysis to identify institutions with strong international collaborative relationships in astronomical research. We find that the strongest ties tend to link institutions across continents in research collaboration. However, the effect of geographic factors is still notable in light of the fact that most of the institutions in the largest subgroup are located in Europe. Examination of the network position, measured by degree centrality, indicates that homophily is more common than heterophily in the network. A relatively high number of relational ties are observed among institutions that have similar levels of network centrality. Mutual relations are prevalent among central institutions, while strong mutual solidarity exists between institutions on the periphery of the network. This study shows a general unstable international collaborative relationship among astronomical institutions. While more and more institutions have linked up in research collaboration, many of them keep relatively weak ties. Institutions tend not remain in the same subgroup, but link to different partners over time.

Resistance to the current therapies is the main clinical challenge in the treatment of lethal metastatic prostate cancer (mPCa). Developing novel therapeutic approaches with effective regimes and minimal side effects for this fatal disease remain a priority in prostate cancer study. In the present study, we demonstrated that a traditional Chinese medicine, quality-assured Ganoderma tsugae ethanol extract (GTEE), significantly suppressed cell growth and metastatic capability and caused cell cycle arrest through decreasing expression of cyclins in mPCa cells, PC-3 and DU145 cells. GTEE also induced caspase-dependent apoptosis in mPCa cells. We further showed the potent therapeutic efficacy of GTEE by inhibiting subcutaneous PC-3 tumor growth in a xenograft model. The in vitro and in vivo efficacies on mPCa cells were due to blockade of the PI3K/Akt and MAPK/ERK signaling pathways associated with cancer cell growth, survival and apoptosis. These preclinical data provide the molecular basis for a new potential therapeutic approach toward the treatment of lethal prostate cancer progression.

The study explores the international collaboration network consisting of 606 astronomical institutions through the analysis of international coauthored papers published in six journals in astronomy and astrophysics from 2001 to 2009. It shows that the Istituto Nazionale di Astrofisica (INAF) and European Southern Observatory (ESO) are the most notable actors, with the highest values of centrality in the network, while Japan Meteorological Agency (JMA) is the only institution that is completely separated from others. It is observed that national academies in major countries, international organizations, and large observatories are more likely to be the central actors. Yet some world-famous astronomical institutions, such as CfA, NASA, and Caltech, are identified as remarkable actors in the network, they show no strikingly high scores in the centrality measures. Overall, astronomical institutions' network position varies with time; nevertheless, not all of institutions present considerable changes during the investigation periods. While some institutions moved from central to relative peripheral positions, or in the opposite direction, the institutions which are positioned at the very center of the network tend to be stable over time.

This study investigates the trend of global concentration in scientific research and technological innovation around the world. It accepts papers and patents as appropriate data for revealing the development and status of science and technology respectively. The performance of these outputs in production and citation impact is taken into consideration in the analysis. The findings suggest that both papers and patents are geographically concentrated on a small number of countries, including the United States, the United Kingdom, Japan, Germany, and France. China has made great progress in paper production and citation impact, and Taiwan and Korea have experienced a rapid growth in patents over the past years. The degree of concentration dramatically decreases when the data from the United States are excluded, indicating the effects of the U.S.’s participation on the concentration. Patents show a higher degree of concentration than papers. With time-varying aspects taken into consideration, the study indicates that the degree of concentration of papers and patents has gradually decreased over time. The concentration of patents has declined more slowly than that of papers. This decrease of the concentration is mainly due to the reduction of the predominant role of the U.S. in world R&D output.

The present study analyzes bibliometric characteristics of Taiwan's highly cited papers published from 2000 to 2009. During this period, Taiwan ranked within the top 30 countries by number of highly cited papers, defined in Thomson Reuters' Essential Science Indicators (ESI) as those that rank in the top 1 % by citations for their category and year of publication. Taiwan made notable progress in world-class research in the two consecutive 5-year periods 2000---2004 and 2005---2009. For the group of highly cited papers from Taiwan, USA, China, Germany, and Japan were the top collaborating countries over the decade. In recent years, Taiwan has increasingly collaborated with European countries whose output of highly cited papers is relatively high and increasing, rather than with its neighboring countries in Asia. Overall, Taiwan produced highly cited papers in all the 22 ESI subject categories during the 10-year period. Taiwan's output of highly cited papers was greatest in the categories of Engineering, Clinical Medicine, and Physics, while those in Agricultural Sciences and Mathematics exceeded the expected output level in relative terms. More detailed analyses would be useful for a holistic understanding of Taiwan's research landscape and their progress in world-class research, combining both bibliometric and non-bibliometric data, such as researcher mobility, research grants, and output from internationally-collaborated research programs.

Publications have been regarded as the most significant output indicating the research performance of universities. This paper uses ISI Essential Science Indicators (ESI) database to investigate the academic performance of research-oriented universities in Taiwan, adopting the bibliometric method from both quantitative and qualitative perspectives. The data cover the time span for 11 years from 1993 to 2003. The performance indicators applied in this study includes the number of papers, the number of citations, the average citations per paper, the number of highly cited papers, the number of hot papers, and the number of top papers. The research performance and the strength of those universities are revealed in this study, and it is found that National Taiwan University leads among these universities though each university still shows strengths in various specific fields.

This paper uses United States patent classification analysis to study the development of core technologies and key industries in Taiwan over the last 25 years, from 1978 to 2002. After counting the number of Taiwan-held United States granted utility patents, the authors divide the years into three phases: from 1978 to 1994, with less than 500 patents each year; from 1995 to 1999, with 500-2,500 patents each year; from 2000 to 2002, with annual patents greater than 2,500. The results show that for both Taiwan’s core technologies and key industries, there was a great diversity at the first phase, while a mainstream forms and matures at the second and the third phases. However, industrial development at the third phase was more concentrated and focused than previous ones. Overall, Taiwan has clearly moved from a manufacturing-based economy to an innovation-based one, with its focus on high-tech industries during the previous 25 years.