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81.
Kenne M Mony R Tindo M Njaleu LC Orivel J Dejean A 《Comptes rendus biologies》2005,328(10-11):1025-1030
Workers of the pest ant Paratrechina longicornis participate in a type of group hunting. Each individual forages with its long antennae wide open and moves quickly (6.3 cm/s) along an erratic path surrounded by nestmates behaving in the same way and within range of a recruiting pheromone. They detect prey by contact with successful workers singly capturing and retrieving small prey and seizing larger ones by an appendage. Then they recruit nestmates at short-range; all together they spread-eagle the prey and retrieve them whole. 相似文献
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83.
Muscle satellite cell heterogeneity: in vitro and in vivo evidences for populations that fuse differently 总被引:2,自引:0,他引:2
Rouger K Brault M Daval N Leroux I Guigand L Lesoeur J Fernandez B Cherel Y 《Cell and tissue research》2004,317(3):319-326
During development, muscle growth results from the proliferation of satellite cells (SC) and their fusion with fibers. Several studies revealed heterogeneity of SC population notably based on the proliferation rate. Here, we examined the SC characteristics of turkey skeletal muscles in terms of proliferation and more specifically fusion, to define if the ability of these cells to fuse may represent a distinct characteristic between them and could be directly associated with their proliferation properties. Freshly extracted SC were plated in clonal condition and their proliferation rate was assessed 11 days later. To investigate the SC fusion behavior, in vitro and in vivo approaches were developed. Highly and slowly proliferative SC were initially labeled with a nuclear -galactosidase (-Gal) activity and co-cultured with differentiated primary cultures. After 5 days, distribution of -Gal positive (-Gal+) nuclei was examined. Also, the two labeled SC types were transplanted into different muscles in autologous model. One week later, number of -Gal+ nuclei per fiber and diameter of fibers displaying -Gal+ nuclei were determined. In vitro, we showed that SC from turkey skeletal muscle are present as a heterogeneous population in terms of proliferation. Examination of their fusion properties in vitro as well as in vivo revealed that highly proliferative SC exclusively exhibited fusion with differentiated myotubes or myofibers, whereas slowly proliferative SC mainly fused together. Collectively, these data demonstrate for the first time that SC with different proliferation rate also intrinsically differ in their fusion potential, suggesting distinct roles for these sub-populations in muscle growth. 相似文献
84.
Bechet D Tassa A Taillandier D Combaret L Attaix D 《The international journal of biochemistry & cell biology》2005,37(10):2098-2114
Lysosomal proteases are abundantly expressed in fetal muscles, but poorly represented in the adult skeletal muscles. The lysosomal proteolytic system is nonetheless stimulated in adult muscles in a variety of pathological conditions. Furthermore, recent investigations describe autophagosomes in muscle fibers in vitro and in vivo, and report myopathies with excessive autophagy. This review presents our current knowledge about the lysosomal proteolytic system and summarizes the evidences pertaining to the role of lysosomes and autophagosomes in muscle physiology and pathology. 相似文献
85.
Increased blood myeloid dendritic cells and dendritic cell-poietins in Langerhans cell histiocytosis 总被引:1,自引:0,他引:1
Rolland A Guyon L Gill M Cai YH Banchereau J McClain K Palucka AK 《Journal of immunology (Baltimore, Md. : 1950)》2005,174(5):3067-3071
Langerhans cell histiocytosis (LCH), previously known as histiocytosis X, is a reactive proliferative disease of unknown pathogenesis. Current therapies are based on nonspecific immunosuppression. Because multiple APCs, including Langerhans cells and macrophages, are involved in the lesion formation, we surmised that LCH is a disease of myeloid blood precursors. We found that lin(-) HLA-DR(+)CD11c-+ precursors of dendritic cells, able to give rise to either Langerhans cells or macrophages, are significantly (p = 0.004) increased in the blood of LCH patients. The analysis of serum cytokines in 24 patients demonstrated significantly elevated levels of hemopoietic cytokines such as fms-like tyrosine kinase ligand (FLT3-L, a dendritic cell-mobilizing factor, approximately 2-fold) and M-CSF ( approximately 4-fold). Higher levels of these cytokines correlated with patients having more extensive disease. Serum levels of FLT3-L and M-CSF were highest in high risk patients with extensive skin and/or multisystem involvement. Finally, patients with bone lesions had relatively higher levels of M-CSF and of stem cell factor. Thus, early hemopoietic cytokines such as FLT3-L, stem cell factor, and M-CSF maybe relevant in LCH pathogenesis and might be considered as novel therapeutic targets. 相似文献
86.
Industrial-scale proteomics: from liters of plasma to chemically synthesized proteins 总被引:5,自引:0,他引:5
Rose K Bougueleret L Baussant T Böhm G Botti P Colinge J Cusin I Gaertner H Gleizes A Heller M Jimenez S Johnson A Kussmann M Menin L Menzel C Ranno F Rodriguez-Tomé P Rogers J Saudrais C Villain M Wetmore D Bairoch A Hochstrasser D 《Proteomics》2004,4(7):2125-2150
Human blood plasma is a useful source of proteins associated with both health and disease. Analysis of human blood plasma is a challenge due to the large number of peptides and proteins present and the very wide range of concentrations. In order to identify as many proteins as possible for subsequent comparative studies, we developed an industrial-scale (2.5 liter) approach involving sample pooling for the analysis of smaller proteins (M(r) generally < ca. 40 000 and some fragments of very large proteins). Plasma from healthy males was depleted of abundant proteins (albumin and IgG), then smaller proteins and polypeptides were separated into 12 960 fractions by chromatographic techniques. Analysis of proteins and polypeptides was performed by mass spectrometry prior to and after enzymatic digestion. Thousands of peptide identifications were made, permitting the identification of 502 different proteins and polypeptides from a single pool, 405 of which are listed here. The numbers refer to chromatographically separable polypeptide entities present prior to digestion. Combining results from studies with other plasma pools we have identified over 700 different proteins and polypeptides in plasma. Relatively low abundance proteins such as leptin and ghrelin and peptides such as bradykinin, all invisible to two-dimensional gel technology, were clearly identified. Proteins of interest were synthesized by chemical methods for bioassays. We believe that this is the first time that the small proteins in human blood plasma have been separated and analyzed so extensively. 相似文献
87.
Allet N Barrillat N Baussant T Boiteau C Botti P Bougueleret L Budin N Canet D Carraud S Chiappe D Christmann N Colinge J Cusin I Dafflon N Depresle B Fasso I Frauchiger P Gaertner H Gleizes A Gonzalez-Couto E Jeandenans C Karmime A Kowall T Lagache S Mahé E Masselot A Mattou H Moniatte M Niknejad A Paolini M Perret F Pinaud N Ranno F Raimondi S Reffas S Regamey PO Rey PA Rodriguez-Tomé P Rose K Rossellat G Saudrais C Schmidt C Villain M Zwahlen C 《Proteomics》2004,4(8):2333-2351
We present an integrated proteomics platform designed for performing differential analyses. Since reproducible results are essential for comparative studies, we explain how we improved reproducibility at every step of our laboratory processes, e.g. by taking advantage of the powerful laboratory information management system we developed. The differential capacity of our platform is validated by detecting known markers in a real sample and by a spiking experiment. We introduce an innovative two-dimensional (2-D) plot for displaying identification results combined with chromatographic data. This 2-D plot is very convenient for detecting differential proteins. We also adapt standard multivariate statistical techniques to show that peptide identification scores can be used for reliable and sensitive differential studies. The interest of the protein separation approach we generally apply is justified by numerous statistics, complemented by a comparison with a simple shotgun analysis performed on a small volume sample. By introducing an automatic integration step after mass spectrometry data identification, we are able to search numerous databases systematically, including the human genome and expressed sequence tags. Finally, we explain how rigorous data processing can be combined with the work of human experts to set high quality standards, and hence obtain reliable (false positive < 0.35%) and nonredundant protein identifications. 相似文献
88.
The equilibrium of membrane fusion and fission influences the volume and copy number of organelles. Fusion of yeast vacuoles has been well characterized but their fission and the mechanisms determining vacuole size and abundance remain poorly understood. We therefore attempted to systematically characterize factors necessary for vacuole fission. Here, we present results of an in vivo screening for deficiencies in vacuolar fragmentation activity of an ordered collection deletion mutants, representing 4881 non-essential genes of the yeast Saccharomyces cerevisiae. The screen identified 133 mutants with strong defects in vacuole fragmentation. These comprise numerous known fragmentation factors, such as the Fab1p complex, Tor1p, Sit4p and the V-ATPase, thus validating the approach. The screen identified many novel factors promoting vacuole fragmentation. Among those are 22 open reading frames of unknown function and three conspicuous clusters of proteins with known function. The clusters concern the ESCRT machinery, adaptins, and lipases, which influence the production of diacylglycerol and phosphatidic acid. A common feature of these factors of known function is their capacity to change membrane curvature, suggesting that they might promote vacuole fragmentation via this property. 相似文献
89.
90.
David R. Braun John Tyler Faith Matthew J. Douglass Benjamin Davies Mitchel J. Power Vera Aldeias Nicholas J. Conard Russell Cutts Larisa R. G. DeSantis Lydie M. Dupont Irene Esteban Andrew W. Kandel Naomi E. Levin Julie Luyt John Parkington Robyn Pickering Lynne Quick Judith Sealy Deano Stynder 《Evolutionary anthropology》2021,30(1):50-62
Despite advances in our understanding of the geographic and temporal scope of the Paleolithic record, we know remarkably little about the evolutionary and ecological consequences of changes in human behavior. Recent inquiries suggest that human evolution reflects a long history of interconnections between the behavior of humans and their surrounding ecosystems (e.g., niche construction). Developing expectations to identify such phenomena is remarkably difficult because it requires understanding the multi‐generational impacts of changes in behavior. These long‐term dynamics require insights into the emergent phenomena that alter selective pressures over longer time periods which are not possible to observe, and are also not intuitive based on observations derived from ethnographic time scales. Generative models show promise for probing these potentially unexpected consequences of human‐environment interaction. Changes in the uses of landscapes may have long term implications for the environments that hominins occupied. We explore other potential proxies of behavior and examine how modeling may provide expectations for a variety of phenomena. 相似文献