The genomes of two key bumblebee species with primitive eusocial organization

Background: The shift from solitary to social behavior is one of the major evolutionary transitions. Primitively eusocial bumblebees are uniquely placed to illuminate the evolution of highly eusocial insect societies. Bumblebees are also invaluable natural and agricultural pollinators, and there is widespread concern over recent population declines in some species. High-quality genomic data will inform key aspects of bumblebee biology, including susceptibility to implicated population viability threats. Results: We report the high quality draft genome sequences of Bombus terrestris and Bombus impatiens, two ecologically dominant bumblebees and widely utilized study species. Comparing these new genomes to those of the highly eusocial honeybee Apis mellifera and other Hymenoptera, we identify deeply conserved similarities, as well as novelties key to the biology of these organisms. Some honeybee genome features thought to underpin advanced eusociality are also present in bumblebees, indicating an earlier evolution in the bee lineage. Xenobiotic detoxification and immune genes are similarly depauperate in bumblebees and honeybees, and multiple categories of genes linked to social organization, including development and behavior, show high conservation. Key differences identified include a bias in bumblebee chemoreception towards gustation from olfaction, and striking differences in microRNAs, potentially responsible for gene regulation underlying social and other traits. Conclusions: These two bumblebee genomes provide a foundation for post-genomic research on these key pollinators and insect societies. Overall, gene repertoires suggest that the route to advanced eusociality in bees was mediated by many small changes in many genes and processes, and not by notable expansion or depauperation

Tunable emission properties of CdSe/CdS quantum dots by Ce doping

A facile one-step hydrothermal synthesis to prepare cerium (Ce3+) ion doped CdSe/CdS core/shell quantum dots (QDs) is introduced. The effect of Ce3+ ion doping on structural and optical properties of the CdSe/CdS core/shell QDs is comprehensively investigated. With increasing Ce doping concentration, a linear increase in the lattice parameter is observed, suggesting the successful coupling of Ce3+ ions to the CdSe/CdS QDs. X-ray photoelectron spectroscopy reveals strong peaks of the Ce3+ state, indicating that Ce is initially present mainly in the Ce3+ ion state. In addition, red-shift over the range 538–569 nm is observed in the photoluminescence (PL) spectra of Ce3+ ion doped CdSe/CdS QDs. Results clearly indicates that the PL peak positions of the CdSe/CdS QDs could be controlled by the Ce content. This study highlights a new approach to tune the emission of the QDs

Cancer Biomarker Discovery: The Entropic Hallmark

Background: It is a commonly accepted belief that cancer cells modify their transcriptional state during the progression of the disease. We propose that the progression of cancer cells towards malignant phenotypes can be efficiently tracked using high-throughput technologies that follow the gradual changes observed in the gene expression profiles by employing Shannon's mathematical theory of communication. Methods based on Information Theory can then quantify the divergence of cancer cells' transcriptional profiles from those of normally appearing cells of the originating tissues. The relevance of the proposed methods can be evaluated using microarray datasets available in the public domain but the method is in principle applicable to other high-throughput methods. Methodology/Principal Findings: Using melanoma and prostate cancer datasets we illustrate how it is possible to employ Shannon Entropy and the Jensen-Shannon divergence to trace the transcriptional changes progression of the disease. We establish how the variations of these two measures correlate with established biomarkers of cancer progression. The Information Theory measures allow us to identify novel biomarkers for both progressive and relatively more sudden transcriptional changes leading to malignant phenotypes. At the same time, the methodology was able to validate a large number of genes and processes that seem to be implicated in the progression of melanoma and prostate cancer. Conclusions/Significance: We thus present a quantitative guiding rule, a new unifying hallmark of cancer: the cancer cell's transcriptome changes lead to measurable observed transitions of Normalized Shannon Entropy values (as measured by high-throughput technologies). At the same time, tumor cells increment their divergence from the normal tissue profile increasing their disorder via creation of states that we might not directly measure. This unifying hallmark allows, via the the Jensen-Shannon divergence, to identify the arrow of time of the processes from the gene expression profiles, and helps to map the phenotypical and molecular hallmarks of specific cancer subtypes. The deep mathematical basis of the approach allows us to suggest that this principle is, hopefully, of general applicability for other diseases

Pan-cancer analysis of whole genomes

Cancer is driven by genetic change, and the advent of massively parallel sequencing has enabled systematic documentation of this variation at the whole-genome scale(1-3). Here we report the integrative analysis of 2,658 whole-cancer genomes and their matching normal tissues across 38 tumour types from the Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium of the International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA). We describe the generation of the PCAWG resource, facilitated by international data sharing using compute clouds. On average, cancer genomes contained 4-5 driver mutations when combining coding and non-coding genomic elements; however, in around 5% of cases no drivers were identified, suggesting that cancer driver discovery is not yet complete. Chromothripsis, in which many clustered structural variants arise in a single catastrophic event, is frequently an early event in tumour evolution; in acral melanoma, for example, these events precede most somatic point mutations and affect several cancer-associated genes simultaneously. Cancers with abnormal telomere maintenance often originate from tissues with low replicative activity and show several mechanisms of preventing telomere attrition to critical levels. Common and rare germline variants affect patterns of somatic mutation, including point mutations, structural variants and somatic retrotransposition. A collection of papers from the PCAWG Consortium describes non-coding mutations that drive cancer beyond those in the TERT promoter(4); identifies new signatures of mutational processes that cause base substitutions, small insertions and deletions and structural variation(5,6); analyses timings and patterns of tumour evolution(7); describes the diverse transcriptional consequences of somatic mutation on splicing, expression levels, fusion genes and promoter activity(8,9); and evaluates a range of more-specialized features of cancer genomes(8,10-18).Peer reviewe

Taxonomic notes on Meeboldia H. Wolff (Umbelliferae)

Meeboldia (Umbelliferae) is treated as a genus including only two species, i.e. M yunnanensis and M. achilleifolia

Facile one-step coating approach to magnetic submicron particles with poly(ethylene glycol) coats and abundant accessible carboxyl groups

Gaobo Long,1,* Xiao-lan Yang,1,* Yi Zhang,1 Jun Pu,2 Lin Liu,1 Hong-bo Liu,1 Yuan-li Li,1 Fei Liao11Unit for Analytical Probes and Protein Biotechnology, Key Laboratory of Clinical Laboratory Diagnostics of the Education Ministry, College of Laboratory Medicine, 2Department of Urology, the First Affiliated Hospital, Chongqing Medical University, Chongqing, People's Republic of China*These authors contributed equally to this workPurpose: Magnetic submicron particles (MSPs) are pivotal biomaterials for magnetic separations in bioanalyses, but their preparation remains a technical challenge. In this report, a facile one-step coating approach to MSPs suitable for magnetic separations was investigated.Methods: Poly(ethylene glycol) (PEG) was derived into PEG-bis-(maleic monoester) and maleic monoester-PEG-succinic monoester as the monomers. Magnetofluids were prepared via chemical co-precipitation and dispersion with the monomers. MSPs were prepared via one-step coating of magnetofluids in a water-in-oil microemulsion system of aerosol-OT and heptane by radical co-polymerization of such monomers.Results: The resulting MSPs contained abundant carboxyl groups, exhibited negligible nonspecific adsorption of common substances and excellent suspension stability, appeared as irregular particles by electronic microscopy, and had submicron sizes of broad distribution by laser scattering. Saturation magnetizations and average particle sizes were affected mainly by the quantities of monomers used for coating magnetofluids, and steric hindrance around carboxyl groups was alleviated by the use of longer monomers of one polymerizable bond for coating. After optimizations, MSPs bearing saturation magnetizations over 46 emu/g, average sizes of 0.32 µm, and titrated carboxyl groups of about 0.21 mmol/g were obtained. After the activation of carboxyl groups on MSPs into N-hydroxysuccinimide ester, biotin was immobilized on MSPs and the resulting biotin-functionalized MSPs isolated the conjugate of streptavidin and alkaline phosphatase at about 2.1 mg/g MSPs; streptavidin was immobilized at about 10 mg/g MSPs and retained 81% ± 18% (n = 5) of the specific activity of the free form.Conclusion: The facile approach effectively prepares MSPs for magnetic separations.Keywords: magnetic submicron particles, carboxyl groups, PEG-bis-(maleic monoester), monomer, radical co-polymerization, steric hindranc

An in vitro and in vivo study of gemcitabine-loaded albumin nanoparticles in a pancreatic cancer cell line

Xinzhe Yu,1,* Yang Di,2,* Chao Xie,3 Yunlong Song,4 Hang He,2 Hengchao Li,1 Xinming Pu,5 Weiyue Lu,3 Deliang Fu,2 Chen Jin1 1Pancreatic Surgery Department, Huashan Hospital, 2Pancreatic Disease Institute, Fudan University, 3School of Pharmacy & Key Laboratory of Smart Drug Delivery, Fudan University, 4School of Pharmacy, The Second Military Medical University, 5The State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science, Fudan University, Shanghai, People’s Republic of China *These authors contributed equally to this work Background and objectives: Gemcitabine (Gem) is far from satisfactory as the first-line regimen for pancreatic cancer, and the emergence of albumin nanoparticles offers new hope for the delivery of Gem. In this study, Gem-loaded human serum albumin nanoparticles (Gem-HSA-NPs) were successfully synthesized, characterized, and tested on a BxPC-3 cell line both in vitro and in vivo.Materials and methods: 4-N-myristoyl-gemcitabine (Gem-C14) was obtained first by coupling myristoyl with the 4-amino group of Gem. The Gem-HSA-NPs were then prepared by nanoparticle albumin-bound technology and characterized for particle size, zeta potential, morphology, encapsulation efficiency, drug-loading efficiency, and release characteristics. Using both in vitro and in vivo studies, Gem-C14 and Gem-HSA-NPs were tested on the human pancreatic cancer cell line BxPC-3.Results: Gem-HSA-NPs showed an average particle size of 150±27 nm, and with an encapsulation rate of 82.99%±3.5% and a drug-loading rate of 10.42%±3.5%, they exhibited a favorable controlled- and sustained-release nature. In in vitro, Gem-C14 was equivalent in cytotoxicity to Gem. In in vivo, the Gem-HSA-NPs exhibited the strongest inhibitory effect on tumor growth but the lowest toxicity among the four groups.Conclusion: The enhanced in vivo efficacy of Gem-HSA-NPs toward the pancreatic cancer cell line suggests their potential role for use in the clinical field. Keywords: pancreatic cancer, gemcitabine, albumin nanoparticles, BxPC-3 cell line, in vitro study, in vivo stud