The Annual Glaciohydrology Cycle in the Ablation Zone of the Greenland Ice Sheet: Part 2. Observed and Modeled Ice Flow

Ice velocities observed in 2005/06 at three GPS stations along the Sermeq Avannarleq flowline, West Greenland, are used to characterize an observed annual velocity cycle. We attempt to reproduce this annual ice velocity cycle using a 1-D ice-flow model with longitudinal stresses coupled to a 1-D hydrology model that governs an empirical basal sliding rule. Seasonal basal sliding velocity is parameterized as a perturbation of prescribed winter sliding velocity that is proportional to the rate of change of glacier water storage. The coupled model reproduces the broad features of the annual basal sliding cycle observed along this flowline, namely a summer speed-up event followed by a fall slowdown event. We also evaluate the hypothesis that the observed annual velocity cycle is due to the annual calving cycle at the terminus. We demonstrate that the ice acceleration due to a catastrophic calving event takes an order of magnitude longer to reach CU/ETH ('Swiss') Camp (46km upstream of the terminus) than is observed. The seasonal acceleration observed at Swiss Camp is therefore unlikely to be the result of velocity perturbations propagated upstream via longitudinal coupling. Instead we interpret this velocity cycle to reflect the local history of glacier water balance

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

Identification of Novel Molecular Targets for Endometrial Cancer Using a Drill-Down LC-MS/MS Approach with iTRAQ

BACKGROUND: The number of patients with endometrial carcinoma (EmCa) with advanced stage or high histological grade is increasing and prognosis has not improved for over the last decade. There is an urgent need for the discovery of novel molecular targets for diagnosis, prognosis and treatment of EmCa, which will have the potential to improve the clinical strategy and outcome of this disease. METHODOLOGY AND RESULTS: We used a "drill-down" proteomics approach to facilitate the identification of novel molecular targets for diagnosis, prognosis and/or therapeutic intervention for EmCa. Based on peptide ions identified and their retention times in the first LC-MS/MS analysis, an exclusion list was generated for subsequent iterations. A total of 1529 proteins have been identified below the Proteinpilot® 5% error threshold from the seven sets of iTRAQ experiments performed. On average, the second iteration added 78% new peptides to those identified after the first run, while the third iteration added 36% additional peptides. Of the 1529 proteins identified, only 40 satisfied our criteria for significant differential expression in EmCa in comparison to normal proliferative tissues. These proteins included metabolic enzymes (pyruvate kinase M2 and lactate dehydrogenase A); calcium binding proteins (S100A6, calcyphosine and calumenin), and proteins involved in regulating inflammation, proliferation and invasion (annexin A1, interleukin enhancer-binding factor 3, alpha-1-antitrypsin, macrophage capping protein and cathepsin B). Network analyses revealed regulation of these molecular targets by c-myc, Her2/neu and TNF alpha, suggesting intervention with these pathways may be a promising strategy for the development of novel molecular targeted therapies for EmCa. CONCLUSIONS: Our analyses revealed the significance of drill-down proteomics approach in combination with iTRAQ to overcome some of the limitations of current proteomics strategies. This study led to the identification of a number of novel molecular targets having therapeutic potential for targeted molecular therapies for endometrial carcinoma

Utility of p16ink4a immunocytochemistry in liquid-based cytology specimens from women treated for high-grade squamous intraepithelial lesions

Objective: To examine whether p16ink4a immunocytochemical (ICC) expression detected intraepithelial disease in liquid-based cytology (LBC) specimens from women with high-grade squamous intraepithelial lesions (HSIL), whose specimen was labeled negative for intraepithelial lesion or malignancy (NILM). Study Design: Residual LBC specimens from women treated for HSIL (n=3D21), whose LBC test was interpreted as NILM including marked benign inflammatory changes (BCC) were used. The control (n=3D25) consisted of residual LBC specimens from women with documented HSIL. ICC for p16ink4a was performed on a second ThinPrep (ThinPrep 2000, Cylyl Corporation, Boxborough, Massachusetts, U.S.A.) preparation; the percentage of positive cells and intensity of immunostaining were recorded. Standard LBC preparations for p16ink4a ICC-positive and ICC-negative control cases were reviewed. Results: Twenty-four of 25 (96%) of the HSIL control group were ICC p16ink4a positive. In the NILM/BCC group, 2 of 21 with adequate LBC residua were ICC p16ink4a positive; on review both were reclassified as epithelial abnormality\u971 HSIL and 1 atypical squamous cells cannot exclude HSIL. In both, subsequent colposcopic biopsy yielded HSIL. Conclusion: p16ink4a ICC positivity on NILM/BCC LBC residua from patients with HSIL may identify cases that merit cytologic review and possible reclassification. The utility of p16ink4a ICC in this situation requires further study

Cervical Cytology Specimen Adequacy: Patient Management Guidelines And Optimizing Specimen Collection

OBJECTIVE. To provide updated management guidelines according to cervical cytology specimen adequacy and techniques to optimize adequacy based on literature review and expert opinion. MATERIALS AND METHODS. Selected members of the American Society for Colposcopy and Cervical Pathology committee and invited experts conducted a literature review and discussed appropriate management and areas for future research emphasis. RESULTS. The guidelines recommend a repeat Pap test in a short interval of 2 to 4 months for most women when the cytology result is unsatisfactory. The preferred follow-up for women with a negative cytology result lacking an endocervical/transformation zone component or showing other quality indicators is a repeat Pap test in 12 months. Indications for an early repeat Pap test in 6 months are provided, and the influence of human papillomavirus testing results on management is discussed. Techniques for optimizing specimen adequacy are provided in detail. CONCLUSION. The specimen adequacy management guidelines will help promote uniform and optimal follow-up of patients receiving cervical cytology screening. The topics for future research emphasis will be helpful in promoting studies in needed areas. ©2008The American Society for Colposcopy and Cervical Pathology