A Biomedically Enriched Collection of 7000 Human ORF Clones

We report the production and availability of over 7000 fully sequence verified plasmid ORF clones representing over 3400 unique human genes. These ORF clones were derived using the human MGC collection as template and were produced in two formats: with and without stop codons. Thus, this collection supports the production of either native protein or proteins with fusion tags added to either or both ends. The template clones used to generate this collection were enriched in three ways. First, gene redundancy was removed. Second, clones were selected to represent the best available GenBank reference sequence. Finally, a literature-based software tool was used to evaluate the list of target genes to ensure that it broadly reflected biomedical research interests. The target gene list was compared with 4000 human diseases and over 8500 biological and chemical MeSH classes in ∼15 Million publications recorded in PubMed at the time of analysis. The outcome of this analysis revealed that relative to the genome and the MGC collection, this collection is enriched for the presence of genes with published associations with a wide range of diseases and biomedical terms without displaying a particular bias towards any single disease or concept. Thus, this collection is likely to be a powerful resource for researchers who wish to study protein function in a set of genes with documented biomedical significance

Drought Impact on Vegetation Productivity in the Lower Mekong Basin

The Lower Mekong Basin (LMB) has a typical monsoon climate, with high temperature and uneven distribution of precipitation throughout the year. As a result of climate change, the LMB has experienced extreme weather conditions during the past few decades. Few studies have focused on changes in net primary productivity (NPP) and the impacts of drought on NPP in the LMB. In th is study, we use MOD17 product to detect variations in NPP during the period 2000–2011 and assess the imapcts of climate and drought on NPP in the LMB. We found that: (1) NPP in the LMB has large variations during the period 2000-2011. Among the five countries, Cambodia experienced the largest NPP variations where is dominated by evergreen forest. Whereas NPP variation was the least in Thailand where is dominated by cropland. (2) Increased temperature caused reduced NPP, therefore negative correlation between temperature and NPP anomaly was identified in Lao PDR. In Cambodia and Southern Lao PDR, decreased precipitation caused reduced NPP, therefore positive correlation between precipitation and NPP was identified. (3) Severe droughts occurred in 2005 and 2010, which induced NPP reductions of 14.7% and 8.4%, respectively. Cambodia was the most severely affected country in 2005, with NPP reductions of 22%. Lao PDR was the most severely affected country in 2010, with NPP reduction of 12.6%. (4) Other factors, such as flooding and human activity, may also have impacts on NPP variations

A novel approach for amplification and purification of mouse oligodendrocyte progenitor cells

Although transgenic and knockout mice are widely used to study the specification and differentiation of oligodendrocyte precursor cells (OPCs), mouse primary OPCs are difficult to be purified and maintained, and many in vitro studies have to resort to rat OPCs as substitutes. In this study, we reported that mouse O4 negative early-stage OPCs can be obtained by culturing cortical tissue blocks, and the simultaneous treatment of OPCs with PDGFaa, bFGF and EGF is the key for the propagation of mouse OPCs in culture. Epidermal growth factor (EGF) was found to be a potent mitogen for OPCs and cooperate with Platelet Derived Growth Factor-AA (PDGFaa) to extend cell division and inhibit their differentiation. EGF also collaborates with PDGFaa and basic fibroblast growth factor (bFGF) to convert bipolar or tripolar OPCs to more vital fibroblast-like OPCs without compromising their oligodendrocyte differentiation potential. In addition, EGF promoted the survival and proliferation of glial progenitor cells (GPCs) derived from primary OPC cultures, and a mixture of GPCs and OPCs can be obtained and propagated in the presence of EGF, bFGF and PDGFaa. Once EGF is withdrawn, GPC population decreased sharply and fibroblast-like OPCs changed into typical OPCs morphology, then homogeneous OPCs were obtained subsequently

Recrystallization of Quenched β‑Form Isotactic Polypropylene Lamellar Crystals in Thin Films

The melting–recrystallization characterizations of quenched β-form isotactic polypropylene (β-iPP) lamellar crystals in ultrathin films were investigated via the self-seeding method. We found lath-like shaped α-iPP crystals generated within the region occupied by the initial β-iPP lamellae and calculated their average number density (Nα). Intriguingly, two slopes were derived from the semi-logarithmic plot of Nα versus partial melting temperature (Ts), which reflects that Nα is determined by βα-recrystallization and αα-recrystallization as Ts is below and above 157 °C, respectively. Furthermore, our experimental observations clearly demonstrate that two phase selection pathways, that is, ββ- and βα-recrystallization, are possible upon melting of the quenched β-iPP lamellae. In particular, we found that ββ-recrystallization emerges as the preferred route for the case of an initial β phase with sufficiently high thermal stability, which is probably thermodynamically controlled rather than kinetically controlled. Otherwise, βα-recrystallization will be the dominant process due to the growth kinetics