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111.
Mendes CS Arama E Brown S Scherr H Srivastava M Bergmann A Steller H Mollereau B 《EMBO reports》2006,7(9):933-939
The role of cytochrome c (Cyt c) in caspase activation has largely been established from mammalian cell-culture studies, but much remains to be learned about its physiological relevance in situ. The role of Cyt c in invertebrates has been subject to considerable controversy. The Drosophila genome contains distinct cyt c genes: cyt c-p and cyt c-d. Loss of cyt c-p function causes embryonic lethality owing to a requirement of the gene for mitochondrial respiration. By contrast, cyt c-d mutants are viable but male sterile. Here, we show that cyt c-d regulates developmental apoptosis in the pupal eye. cyt c-d mutant retinas show a profound delay in the apoptosis of superfluous interommatidial cells and perimeter ommatidial cells. Furthermore, there is no apoptosis in mutant retinal tissues for the Drosophila homologues of apoptotic protease-activating factor 1 (Ark) and caspase 9 (Dronc). In addition, we found that cyt c-d--as with ark and dronc-regulates scutellar bristle number, which is known to depend on caspase activity. Collectively, our results indicate a role of Cyt c in caspase regulation of Drosophila somatic cells. 相似文献
112.
Condac E Strachan H Gutierrez-Sanchez G Brainard B Giese C Heiss C Johnson D Azadi P Bergmann C Orlando R Esmon CT Harenberg J Moremen K Wang L 《Glycobiology》2012,22(9):1183-1192
Slit3 is a large molecule with multiple domains and belongs to axon guidance families. To date, the biological functions of Slit3 are still largely unknown. Our recent study demonstrated that the N-terminal fragment of Slit3 is a novel angiogenic factor. In this study, we examined the biological function of the C-terminal fragment of human Slit3 (HSCF). The HSCF showed a high-affinity binding to heparin. The binding appeared to be heparin/heparan sulfate-specific and depends on the size, the degree of sulfation, the presence of N- and 6-O-sulfates and carboxyl moiety of the polysaccharide. Functional studies observed that HSCF inhibited antithrombin binding to heparin and neutralized the antifactor IIa and Xa activities of heparin and the antifactor IIa activity of low-molecular-weight heparin (LMWH). Thromboelastography analysis observed that HSCF reversed heparin's anticoagulation in global plasma coagulation. Taken together, these observations demonstrate that HSCF is a novel heparin-binding protein that potently neutralizes heparin's anticoagulation activity. This study reveals a potential for HSCF to be developed as a new antidote to treat overdosing of both heparin and LMWH in clinical applications. 相似文献
113.
Mapping a songbird fauna with pupils How to induce pupils aged 13 to 14 years to successfully map the songbird fauna of a city park? The mapping project took place within 1.5 hours on an April morning. Pupils were organized as small working groups using maps, binoculars, and field guides produced by themselves. The project had been prepared by a 6 lesson course. Results were later discussed with nature conservancy officials. Pupils having participated in the project displayed increased knowledge of birds and motivation to observe them. 相似文献
114.
115.
Archegozetes longisetosus is a parthenogenetic oribatid mite and a chelicerate model organism. We examined the localisation of processes between vitellogenesis and embryogenesis as well as the anatomy and histology of involved structures by means of light- and electron microscopy. The proximal oviduct is differentiated into an oviductal bulb, exhibiting a strong secretory epithelium. Here, solidification of the egg shell instantaneously occurs upon passing of the egg from the perivitelline space into the oviductal lumen. This is interpreted as an internalised oviposition with the generation boundary being effectively located at the ovary-oviduct transition, rendering the oviducts into functional brood chambers. The parity mode combines elements of oviparity and ovolarviparity with facultative egg retention. 相似文献
116.
Schoening T Bergmann M Ontrup J Taylor J Dannheim J Gutt J Purser A Nattkemper TW 《PloS one》2012,7(6):e38179
Megafauna play an important role in benthic ecosystem function and are sensitive indicators of environmental change. Non-invasive monitoring of benthic communities can be accomplished by seafloor imaging. However, manual quantification of megafauna in images is labor-intensive and therefore, this organism size class is often neglected in ecosystem studies. Automated image analysis has been proposed as a possible approach to such analysis, but the heterogeneity of megafaunal communities poses a non-trivial challenge for such automated techniques. Here, the potential of a generalized object detection architecture, referred to as iSIS (intelligent Screening of underwater Image Sequences), for the quantification of a heterogenous group of megafauna taxa is investigated. The iSIS system is tuned for a particular image sequence (i.e. a transect) using a small subset of the images, in which megafauna taxa positions were previously marked by an expert. To investigate the potential of iSIS and compare its results with those obtained from human experts, a group of eight different taxa from one camera transect of seafloor images taken at the Arctic deep-sea observatory HAUSGARTEN is used. The results show that inter- and intra-observer agreements of human experts exhibit considerable variation between the species, with a similar degree of variation apparent in the automatically derived results obtained by iSIS. Whilst some taxa (e. g. Bathycrinus stalks, Kolga hyalina, small white sea anemone) were well detected by iSIS (i. e. overall Sensitivity: 87%, overall Positive Predictive Value: 67%), some taxa such as the small sea cucumber Elpidia heckeri remain challenging, for both human observers and iSIS. 相似文献
117.
V Gallo JP Mackenbach M Ezzati G Menvielle AE Kunst S Rohrmann R Kaaks B Teucher H Boeing MM Bergmann A Tjønneland SO Dalton K Overvad ML Redondo A Agudo A Daponte L Arriola C Navarro AB Gurrea KT Khaw N Wareham T Key A Naska A Trichopoulou D Trichopoulos G Masala S Panico P Contiero R Tumino HB Bueno-de-Mesquita PD Siersema PP Peeters S Zackrisson M Almquist S Eriksson G Hallmans G Skeie T Braaten E Lund AK Illner T Mouw E Riboli P Vineis 《PloS one》2012,7(7):e39013
Background
Socio-economic inequalities in mortality are observed at the country level in both North America and Europe. The purpose of this work is to investigate the contribution of specific risk factors to social inequalities in cause-specific mortality using a large multi-country cohort of Europeans.Methods
A total of 3,456,689 person/years follow-up of the European Prospective Investigation into Cancer and Nutrition (EPIC) was analysed. Educational level of subjects coming from 9 European countries was recorded as proxy for socio-economic status (SES). Cox proportional hazard model''s with a step-wise inclusion of explanatory variables were used to explore the association between SES and mortality; a Relative Index of Inequality (RII) was calculated as measure of relative inequality.Results
Total mortality among men with the highest education level is reduced by 43% compared to men with the lowest (HR 0.57, 95% C.I. 0.52–0.61); among women by 29% (HR 0.71, 95% C.I. 0.64–0.78). The risk reduction was attenuated by 7% in men and 3% in women by the introduction of smoking and to a lesser extent (2% in men and 3% in women) by introducing body mass index and additional explanatory variables (alcohol consumption, leisure physical activity, fruit and vegetable intake) (3% in men and 5% in women). Social inequalities were highly statistically significant for all causes of death examined in men. In women, social inequalities were less strong, but statistically significant for all causes of death except for cancer-related mortality and injuries.Discussion
In this European study, substantial social inequalities in mortality among European men and women which cannot be fully explained away by accounting for known common risk factors for chronic diseases are reported. 相似文献118.
119.
In this study the saliency of hardness and softness were investigated in an active haptic search task. Two experiments were performed to explore these properties in different contexts. In Experiment 1, blindfolded participants had to grasp a bundle of spheres and determine the presence of a hard target among soft distractors or vice versa. If the difference in compliance between target and distractors was small, reaction times increased with the number of items for both features; a serial strategy was found to be used. When the difference in compliance was large, the reaction times were independent of the number of items, indicating a parallel strategy. In Experiment 2, blindfolded participants pressed their hand on a display filled with hard and soft items. In the search for a soft target, increasing reaction times with the number of items were found, but the location of target and distractors appeared to have a large influence on the search difficulty. In the search for a hard target, reaction times did not depend on the number of items. In sum, this showed that both hardness and softness are salient features. 相似文献
120.
D Schauer P Starlinger C Reiter N Jahn P Zajc E Buchberger T Bachleitner-Hofmann M Bergmann A Stift T Gruenberger C Brostjan 《PloS one》2012,7(9):e44450
We have conducted the first study to determine the diagnostic potential of the CD14++CD16+ intermediate monocytes as compared to the pro-angiogenic subset of CD14++CD16+TIE2+ TIE2-expressing monocytes (TEMs) in cancer. These monocyte populations were investigated by flow cytometry in healthy volunteers (N?=?32) and in colorectal carcinoma patients with localized (N?=?24) or metastatic (N?=?37) disease. We further determined blood levels of cytokines associated with monocyte regulation. The results revealed the intermediate monocyte subset to be significantly elevated in colorectal cancer patients and to show the highest frequencies in localized disease. Multivariate regression analysis identified intermediate monocytes as a significant independent variable in cancer prediction. With a cut-off value at 0.37% (intermediate monocytes of total leukocytes) the diagnostic sensitivity and specificity ranged at 69% and 81%, respectively. In contrast, TEM levels were elevated in localized cancer but did not differ significantly between groups and none of the cytokines correlated with monocyte subpopulations. Of interest, in vitro analyses supported the observation that intermediate monocytes were more potently induced by primary as opposed to metastatic cancer cells which may relate to the immunosuppressive milieu established in the advanced stage of metastatic disease. In conclusion, intermediate monocytes as compared to TIE2-expressing monocytes are a more sensitive diagnostic indicator of colorectal cancer. 相似文献