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41.
Genevieve E. Davis Mark F. Baumgartner Peter J. Corkeron Joel Bell Catherine Berchok Julianne M. Bonnell Jacqueline Bort Thornton Solange Brault Gary A. Buchanan Danielle M. Cholewiak Christopher W. Clark Julien Delarue Leila T. Hatch Holger Klinck Scott D. Kraus Bruce Martin David K. Mellinger Hilary Moors‐Murphy Sharon Nieukirk Douglas P. Nowacek Susan E. Parks Dawn Parry Nicole Pegg Andrew J. Read Aaron N. Rice Denise Risch Alyssa Scott Melissa S. Soldevilla Kathleen M. Stafford Joy E. Stanistreet Erin Summers Sean Todd Sofie M. Van Parijs 《Global Change Biology》2020,26(9):4812-4840
Six baleen whale species are found in the temperate western North Atlantic Ocean, with limited information existing on the distribution and movement patterns for most. There is mounting evidence of distributional shifts in many species, including marine mammals, likely because of climate‐driven changes in ocean temperature and circulation. Previous acoustic studies examined the occurrence of minke (Balaenoptera acutorostrata) and North Atlantic right whales (NARW; Eubalaena glacialis). This study assesses the acoustic presence of humpback (Megaptera novaeangliae), sei (B. borealis), fin (B. physalus), and blue whales (B. musculus) over a decade, based on daily detections of their vocalizations. Data collected from 2004 to 2014 on 281 bottom‐mounted recorders, totaling 35,033 days, were processed using automated detection software and screened for each species' presence. A published study on NARW acoustics revealed significant changes in occurrence patterns between the periods of 2004–2010 and 2011–2014; therefore, these same time periods were examined here. All four species were present from the Southeast United States to Greenland; humpback whales were also present in the Caribbean. All species occurred throughout all regions in the winter, suggesting that baleen whales are widely distributed during these months. Each of the species showed significant changes in acoustic occurrence after 2010. Similar to NARWs, sei whales had higher acoustic occurrence in mid‐Atlantic regions after 2010. Fin, blue, and sei whales were more frequently detected in the northern latitudes of the study area after 2010. Despite this general northward shift, all four species were detected less on the Scotian Shelf area after 2010, matching documented shifts in prey availability in this region. A decade of acoustic observations have shown important distributional changes over the range of baleen whales, mirroring known climatic shifts and identifying new habitats that will require further protection from anthropogenic threats like fixed fishing gear, shipping, and noise pollution. 相似文献
42.
Jean-Marc Bielser Leon Kraus Orlando Burgos-Morales Hervé Broly Jonathan Souquet 《Biotechnology progress》2020,36(5):e3026
Media preparation for perfusion cell culture processes contributes significantly to operational costs and the footprint of continuous operations for therapeutic protein manufacturing. In this study, definitions are given for the use of a perfusion equivalent nutrient feed stream which, when used in combination with basal perfusion medium, supplements the culture with targeted compounds and increases the medium depth. Definitions to compare medium and feed depth are given in this article. Using a concentrated nutrient feed, a 1.8-fold medium consumption (MC) decrease and a 1.67-fold increase in volumetric productivity (PR) were achieved compared to the initial condition. Later, this strategy was used to push cell densities above 100 × 106 cells/ml while using a perfusion rate below 2 RV/day. In this example, MC was also decreased 1.8-fold compared to the initial condition, but due to the higher cell density, PR was increased 3.1-fold and to an average PR value of 1.36 g L−1 day−1 during a short stable phase, and versus 0.46 g L−1 day−1 in the initial condition. Overall, the performance improvements were aligned with the given definitions. This multiple feeding strategy can be applied to gain some flexibility during process development and also in a manufacturing set-up to enable better control on nutrient addition. 相似文献
43.
Birth‐and‐death processes are widely used to model the development of biological populations. Although they are relatively simple models, their parameters can be challenging to estimate, as the likelihood can become numerically unstable when data arise from the most common sampling schemes, such as annual population censuses. A further difficulty arises when the discrete observations are not equi‐spaced, for example, when census data are unavailable for some years. We present two approaches to estimating the birth, death, and growth rates of a discretely observed linear birth‐and‐death process: via an embedded Galton‐Watson process and by maximizing a saddlepoint approximation to the likelihood. We study asymptotic properties of the estimators, compare them on numerical examples, and apply the methodology to data on monitored populations. 相似文献
44.
Bjoern M. Eskofier Martin Kraus Jay T. Worobets Darren J. Stefanyshyn Benno M. Nigg 《Computer methods in biomechanics and biomedical engineering》2013,16(5):467-474
The identification of differences between groups is often important in biomechanics. This paper presents group classification tasks using kinetic and kinematic data from a prospective running injury study. Groups composed of gender, of shod/barefoot running and of runners who developed patellofemoral pain syndrome (PFPS) during the study, and asymptotic runners were classified. The features computed from the biomechanical data were deliberately chosen to be generic. Therefore, they were suited for different biomechanical measurements and classification tasks without adaptation to the input signals. Feature ranking was applied to reveal the relevance of each feature to the classification task. Data from 80 runners were analysed for gender and shod/barefoot classification, while 12 runners were investigated in the injury classification task. Gender groups could be differentiated with 84.7%, shod/barefoot running with 98.3%, and PFPS with 100% classification rate. For the latter group, one single variable could be identified that alone allowed discrimination. 相似文献
45.
DC Chhieng AR Frost S Niwas H Weiss WE Grizzle S Beeken 《Biotechnic & histochemistry》2013,88(1):25-36
Small biopsy samples are used increasingly to assess the biomarker expression for prognostic information and for monitoring therapeutic responses prior to and during neoadjuvant therapy. The issue of intratumor heterogeneity of expression of biomarkers, however, has raised questions about the validity of the assessment of biomarker expression based on limited tissue samples. We examined immunohistochemically the expression of HER-2neu (p185erbB-2), epidermal growth factor receptor (EGFR), Bcl-2, p53, and proliferating cell nuclear antigen (PCNA) in 30 breast carcinomas using archived, paraffin embedded tissue and determined the extent of intratumor heterogeneity. Each section was divided into four randomly oriented discrete regions, each containing a portion of the infiltrating carcinoma. For each tumor, the entire lesion and four regions were analyzed for the expression of these markers. Scores of both membrane and cytoplasmic staining of HER-2neu and EGFR, scores of cytoplasmic staining of Bcl-2, and scores of nuclear staining of both p53 and PCNA were recorded. The intensity of staining and the proportion of immunostained cells were determined. A semiquantitative immunoscore was calculated by determining the sum of the products of the intensity and corresponding proportion of stained tumor cells. We analyzed both invasive (IDC) and in situ (DCIS) carcinomas. The Wilcoxon signed-rank test was used for paired comparisons between overall and regional immunoscores and between overall and regional percentages of stained cells. Spearman's correlation coefficients were used to assess the level of agreement of overall biomarker expression with each of the regions. Generalized linear models were used to assess overall and pair-wise differences in the absolute values of percent changes between overall and regional expression of biomarkers. For IDCs, there were no statistically significant differences in the expression of the biomarkers in terms of either the percentage of cells staining or the immunoscores when comparing the entire tumor with each region except for the lower EGFR expression of arbitrarily selected region 1 and lower p53 expression of region 1 compared to that of the entire tumor section. For DCIS, there were no statistically significant differences in the expression of the biomarkers between the entire tumor and each region except in PCNA of region 2 compared to that of entire tumor section. Positive correlation of immunoscores was observed between the entire tumor and each region as well as across all four regions for IDC. Similar observations were noted with DCIS except for HER-2neu and PCNA. No statistically significant differences were observed in the absolute values of percent changes of biomarker expression between overall and the four regions for both DCIS and IDC. Therefore, no significant intratumor heterogeneity in the expression of HER-2neu, Bcl-2, and PCNA was observed in IDC. Minor regional variations were observed for EGFR and p53 in IDC. Similarly, no significant regional variation in the expression of markers was observed in DCIS except for PCNA. 相似文献
46.
Sophie Aschenberg Stephanie Finzel Sarah Schmidt Sebastian Kraus Klaus Engelke Matthias Englbrecht Jürgen Rech Georg Schett 《Arthritis research & therapy》2013,15(3):R62
Introduction
The aim of this study was to determine the factors, including markers of bone resorption and bone formation, which determine catabolic and anabolic periarticular bone changes in patients with rheumatoid arthritis (RA).Methods
Forty RA patients received high-resolution peripheral quantitative computed tomography (HR-pQCT) analysis of the metacarpophalangeal joints II and III of the dominantly affected hand at two sequential time points (baseline, one year follow-up). Erosion counts and scores as well as osteophyte counts and scores were recorded. Simultaneously, serum markers of bone resorption (C-terminal telopeptide of type I collagen (CTX I), tartrate-resistant acid phosphatase 5b (TRAP5b)), bone formation (bone alkaline phosphatase (BAP), osteocalcin (OC)) and calcium homeostasis (parathyroid hormone (PTH), 25-hydroxyvitamin D3 (Vit D)) were assessed. Bone biomarkers were correlated to imaging data by partial correlation adjusting for various demographic and disease-specific parameters. Additionally, imaging data were analyzed by mixed linear model regression.Results
Partial correlation analysis showed that TRAP5b levels correlate significantly with bone erosions, whereas BAP levels correlate with osteophytes at both time points. In the mixed linear model with erosions as the dependent variable, disease duration (P <0.001) was the key determinant for these catabolic bone changes. In contrast, BAP (P = 0.001) as well as age (P = 0.018), but not disease duration (P = 0.762), were the main determinants for the anabolic changes (osteophytes) of the periarticular bone in patients with RA.Conclusions
This study shows that structural bone changes assessed with HR-pQCT are accompanied by alterations in systemic markers of bone resorption and bone formation. Besides, it can be shown that bone erosions in RA patients depend on disease duration, whereas osteophytes are associated with age as well as serum level of BAP. Therefore, these data not only suggest that different variables are involved in formation of bone erosions and osteophytes in RA patients, but also that periarticular bone changes correlate with alterations in systemic markers of bone metabolism, pointing out BAP as an important parameter. 相似文献47.
Michel Camplo Philippe Faury Anne-Sophie Charvet Florence Lederer Jean-Claude Chermann Jean-Louis Kraus 《Nucleosides, nucleotides & nucleic acids》2013,32(6):631-641
Abstract The synthesis of a new analogue of 2′,3′-dideoxy-3′-thiacytidine 9 covalently linked to an N-formyl methionyl leucyl phenylalanine peptide is described. This new prodrug analogue has been tested on the one hand as activator of human polymorphonuclear leukocytes (an EC50 value of 1.8 10?5 M was determined from dose-response curve for superoxide production) and on the other hand as inhibitor of the syncitium formation caused by HIV-1 in MT4-cells (IC50 = 8.0± 0.8 μM). In so far as this new prodrug possesses these two biological properties, it represents a useful “chemical-head” capable of targeting specific receptors located on leukocytes membranes. 相似文献
48.
Jia-Hui Ng Vibhor Kumar Masafumi Muratani Petra Kraus Jia-Chi Yeo Lai-Ping Yaw Kun Xue Thomas Lufkin Shyam Prabhakar Huck-Hui Ng 《Developmental cell》2013,24(3):324-333
Highlights? Modified small-scale ChIP-seq method applicable to small number of cells ? Genome-wide maps of H3K4me3, H3K27me3, H3K27ac, and H2BK20ac of germ cells in vivo ? Identification of active and inactive regulatory elements in germ cells in vivo ? Germ cell H3K27me3 regions are enriched for retrotransposon repeats 相似文献
49.
Matthias Hardtke-Wolenski Lilli Kraus Christel Schmetz Britta Trautewig Fatih Noyan Florian W. R. Vondran Hueseyin Bektas Juergen Klempnauer Elmar Jaeckel Thorsten Lieke 《PloS one》2013,8(10)
Background
T cells are known to participate in the response to tumor cells and react with cytotoxicity and cytokine release. At the same time tumors established versatile mechanisms for silencing the immune responses. The interplay is far from being completely understood. In this study we show contacts between tumor cells and lymphocytes revealing novel characteristics in the interaction of T cells and cancer cells in a way not previously described.Methods/ Findings
Experiments are based on the usage of a hydrophilic fluorescent dye that occurs free in the cytosol and thus transfer of fluorescent cytosol from one cell to the other can be observed using flow cytometry. Tumor cells from cell lines of different origin or primary hepatocellular carcinoma (HCC) cells were incubated with lymphocytes from human and mice. This exposure provoked a contact dependent uptake of tumor derived cytosol by lymphocytes – even in CD4+ T cells and murine B cells – which could not be detected after incubation of lymphocytes with healthy cells. The interaction was a direct one, not requiring the presence of accessory cells, but independent of cytotoxicity and TCR engagement.Electron microscopy disclosed 100-200nm large gaps in the cell membranes of connected cells which separated viable and revealed astonishing outcome. While the lymphocytes were induced to proliferate in a long term fashion, the tumor cells underwent a temporary break in cell division. The in vitro results were confirmed in vivo using a murine acute lymphoblastic leukemia (ALL) model. The arrest of tumor proliferation resulted in a significant prolonged survival of challenged mice.Conclusions
The reported cell-cell contacts reveal new characteristics i.e. the enabling of cytosol flow between the cells including biological active proteins that influence the cell cycle and biological behaviour of the recipient cells. This adds a completely new aspect in tumor induced immunology. 相似文献50.
Martin Chopra Sabrina Kraus Stefanie Schwinn Miriam Ritz Katharina Mattenheimer Anja Mottok Andreas Rosenwald Hermann Einsele Andreas Beilhack 《PloS one》2013,8(12)
To promote cancer research and to develop innovative therapies, refined pre-clinical mouse tumor models that mimic the actual disease in humans are of dire need. A number of neoplasms along the B cell lineage are commonly initiated by a translocation recombining c-myc with the immunoglobulin heavy-chain gene locus. The translocation is modeled in the C.129S1-Ighatm1(Myc)Janz/J mouse which has been previously engineered to express c-myc under the control of the endogenous IgH promoter. This transgenic mouse exhibits B cell hyperplasia and develops diverse B cell tumors. We have isolated tumor cells from the spleen of a C.129S1-Ighatm1(Myc)Janz/J mouse that spontaneously developed a plasmablastic lymphoma-like disease. These cells were cultured, transduced to express eGFP and firefly luciferase, and gave rise to a highly aggressive, transplantable B cell lymphoma cell line, termed IM380. This model bears several advantages over other models as it is genetically induced and mimics the translocation that is detectable in a number of human B cell lymphomas. The growth of the tumor cells, their dissemination, and response to treatment within immunocompetent hosts can be imaged non-invasively in vivo due to their expression of firefly luciferase. IM380 cells are radioresistant in vivo and mice with established tumors can be allogeneically transplanted to analyze graft-versus-tumor effects of transplanted T cells. Allogeneic hematopoietic stem cell transplantation of tumor-bearing mice results in prolonged survival. These traits make the IM380 model very valuable for the study of B cell lymphoma pathophysiology and for the development of innovative cancer therapies. 相似文献